1
|
Field JK, Duffy SW, Baldwin DR, Whynes DK, Devaraj A, Brain KE, Eisen T, Gosney J, Green BA, Holemans JA, Kavanagh T, Kerr KM, Ledson M, Lifford KJ, McRonald FE, Nair A, Page RD, Parmar MKB, Rassl DM, Rintoul RC, Screaton NJ, Wald NJ, Weller D, Williamson PR, Yadegarfar G, Hansell DM. UK Lung Cancer RCT Pilot Screening Trial: baseline findings from the screening arm provide evidence for the potential implementation of lung cancer screening. Thorax 2015; 71:161-70. [PMID: 26645413 PMCID: PMC4752629 DOI: 10.1136/thoraxjnl-2015-207140] [Citation(s) in RCA: 224] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 11/03/2015] [Indexed: 12/15/2022]
Abstract
Background Lung cancer screening using low-dose CT (LDCT) was shown to reduce lung cancer mortality by 20% in the National Lung Screening Trial. Methods The pilot UK Lung Cancer Screening (UKLS) is a randomised controlled trial of LDCT screening for lung cancer versus usual care. A population-based questionnaire was used to identify high-risk individuals. CT screen-detected nodules were managed by a pre-specified protocol. Cost effectiveness was modelled with reference to the National Lung Cancer Screening Trial mortality reduction. Results 247 354 individuals aged 50–75 years were approached; 30.7% expressed an interest, 8729 (11.5%) were eligible and 4055 were randomised, 2028 into the CT arm (1994 underwent a CT). Forty-two participants (2.1%) had confirmed lung cancer, 34 (1.7%) at baseline and 8 (0.4%) at the 12-month scan. 28/42 (66.7%) had stage I disease, 36/42 (85.7%) had stage I or II disease. 35/42 (83.3%) had surgical resection. 536 subjects had nodules greater than 50 mm3 or 5 mm diameter and 41/536 were found to have lung cancer. One further cancer was detected by follow-up of nodules between 15 and 50 mm3 at 12 months. The baseline estimate for the incremental cost-effectiveness ratio of once-only CT screening, under the UKLS protocol, was £8466 per quality adjusted life year gained (CI £5542 to £12 569). Conclusions The UKLS pilot trial demonstrated that it is possible to detect lung cancer at an early stage and deliver potentially curative treatment in over 80% of cases. Health economic analysis suggests that the intervention would be cost effective—this needs to be confirmed using data on observed lung cancer mortality reduction. Trial registration ISRCTN 78513845.
Collapse
Affiliation(s)
- J K Field
- Roy Castle Lung Cancer Research Programme, Department of Molecular and Clinical Cancer Medicine, University of Liverpool, Liverpool, UK
| | - S W Duffy
- Queen Mary University of London, London, UK
| | - D R Baldwin
- Department of Respiratory Medicine, Nottingham University Hospitals, Nottingham, UK
| | - D K Whynes
- School of Economics, University of Nottingham, Nottingham, UK
| | - A Devaraj
- Royal Brompton and Harefield NHS Foundation Trust, London, UK
| | - K E Brain
- Cardiff University School of Medicine, Cardiff, UK
| | - T Eisen
- University of Cambridge, Cambridge Biomedical Research Centre, Cambridge, UK
| | - J Gosney
- Department of Pathology, Royal Liverpool and Broadgreen University Hospital Trust, Liverpool, UK
| | - B A Green
- Roy Castle Lung Cancer Research Programme, Department of Molecular and Clinical Cancer Medicine, University of Liverpool, Liverpool, UK
| | - J A Holemans
- Liverpool Heart and Chest Hospital, NHS Foundation Trust, Liverpool UK
| | - T Kavanagh
- Lung Cancer Patient Advocate, Liverpool, UK
| | - K M Kerr
- Department of Pathology, Aberdeen Royal Infirmary, Aberdeen, UK
| | - M Ledson
- Liverpool Heart and Chest Hospital, NHS Foundation Trust, Liverpool UK
| | - K J Lifford
- Cardiff University School of Medicine, Cardiff, UK
| | - F E McRonald
- Roy Castle Lung Cancer Research Programme, Department of Molecular and Clinical Cancer Medicine, University of Liverpool, Liverpool, UK
| | - A Nair
- Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - R D Page
- Liverpool Heart and Chest Hospital, NHS Foundation Trust, Liverpool UK
| | - M K B Parmar
- Medical Research Council Clinical Trials Unit at UCL, London, UK
| | - D M Rassl
- Department of Histopathology, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| | - R C Rintoul
- Department of Histopathology, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| | - N J Screaton
- Department of Histopathology, Papworth Hospital NHS Foundation Trust, Cambridge, UK
| | - N J Wald
- Queen Mary University of London, London, UK
| | - D Weller
- Center for Population Health Sciences, University of Edinburgh, Edinburgh, UK
| | - P R Williamson
- Roy Castle Lung Cancer Research Programme, Department of Molecular and Clinical Cancer Medicine, University of Liverpool, Liverpool, UK
| | - G Yadegarfar
- Roy Castle Lung Cancer Research Programme, Department of Molecular and Clinical Cancer Medicine, University of Liverpool, Liverpool, UK
| | - D M Hansell
- Royal Brompton and Harefield NHS Foundation Trust, London, UK
| |
Collapse
|
2
|
Caulfield S, McDonald KA, Dawson B, Stearne SM, Green BA, Rubenson J, Clemons TD, Peeling P. A comparison of haemolytic responses in fore-foot and rear-foot distance runners. J Sports Sci 2015; 34:1485-90. [PMID: 26618486 DOI: 10.1080/02640414.2015.1119300] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
This study examined the haemolytic effects of an interval-based running task in fore-foot and rear-foot striking runners. Nineteen male distance runners (10 fore-foot, 9 rear-foot) completed 8 × 3 min repeats at 90% vVO2peak on a motorised treadmill. Pre- and post-exercise venous blood samples were analysed for serum haptoglobin to quantify the haemolytic response to running. Vertical ground reaction forces were also captured via a force plate beneath the treadmill belt. Haptoglobin levels were significantly decreased following exercise (P = 0.001) in both groups (but not between groups), suggesting that the running task created a haemolytic stress. The ground reaction force data showed strong effect sizes for a greater peak force (d = 1.20) and impulse (d = 1.37) in fore-foot runners, and a greater rate of force development (d = 2.74) in rear-foot runners. The lack of difference in haptoglobin response between groups may be explained by the trend for fore-foot runners to experience greater peak force and impulse during the stance phase of their running gait, potentially negating any impact of the greater rate of force development occurring from the rear-foot runners' heel strike. Neither type of runner (fore-foot or rear-foot) appears more susceptible to technique-related foot-strike haemolysis.
Collapse
Affiliation(s)
- Stuart Caulfield
- a School of Sport Science, Exercise and Health , The University of Western Australia , Crawley , Australia
| | - Kirsty A McDonald
- a School of Sport Science, Exercise and Health , The University of Western Australia , Crawley , Australia
| | - Brian Dawson
- a School of Sport Science, Exercise and Health , The University of Western Australia , Crawley , Australia
| | - Sarah M Stearne
- a School of Sport Science, Exercise and Health , The University of Western Australia , Crawley , Australia
| | - Ben A Green
- a School of Sport Science, Exercise and Health , The University of Western Australia , Crawley , Australia
| | - Jonas Rubenson
- a School of Sport Science, Exercise and Health , The University of Western Australia , Crawley , Australia.,b Biomechanics Laboratory, Department of Kinesiology , Pennsylvania State University , University Park , PA , USA
| | - Tristan D Clemons
- c School of Chemistry and Biochemistry , The University of Western Australia , Crawley , Australia
| | - Peter Peeling
- a School of Sport Science, Exercise and Health , The University of Western Australia , Crawley , Australia
| |
Collapse
|
3
|
Bagci AM, Lee SH, Nagornaya N, Green BA, Alperin N. Automated posterior cranial fossa volumetry by MRI: applications to Chiari malformation type I. AJNR Am J Neuroradiol 2013; 34:1758-63. [PMID: 23493894 DOI: 10.3174/ajnr.a3435] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND PURPOSE Quantification of PCF volume and the degree of PCF crowdedness were found beneficial for differential diagnosis of tonsillar herniation and prediction of surgical outcome in CMI. However, lack of automated methods limits the clinical use of PCF volumetry. An atlas-based method for automated PCF segmentation tailored for CMI is presented. The method performance is assessed in terms of accuracy and spatial overlap with manual segmentation. The degree of association between PCF volumes and the lengths of previously proposed linear landmarks is reported. MATERIALS AND METHODS T1-weighted volumetric MR imaging data with 1-mm isotropic resolution obtained with the use of a 3T scanner from 14 patients with CMI and 3 healthy subjects were used for the study. Manually delineated PCF from 9 patients was used to establish a CMI-specific reference for an atlas-based automated PCF parcellation approach. Agreement between manual and automated segmentation of 5 different CMI datasets was verified by means of the t test. Measurement reproducibility was established through the use of 2 repeated scans from 3 healthy subjects. Degree of linear association between PCF volume and 6 linear landmarks was determined by means of Pearson correlation. RESULTS PCF volumes measured by use of the automated method and with manual delineation were similar, 196.2 ± 8.7 mL versus 196.9 ± 11.0 mL, respectively. The mean relative difference of -0.3 ± 1.9% was not statistically significant. Low measurement variability, with a mean absolute percentage value of 0.6 ± 0.2%, was achieved. None of the PCF linear landmarks were significantly associated with PCF volume. CONCLUSIONS PCF and tissue content volumes can be reliably measured in patients with CMI by use of an atlas-based automated segmentation method.
Collapse
|
4
|
Dididze M, Green BA, Dalton Dietrich W, Vanni S, Wang MY, Levi AD. Systemic hypothermia in acute cervical spinal cord injury: a case-controlled study. Spinal Cord 2012; 51:395-400. [DOI: 10.1038/sc.2012.161] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
|
5
|
Morrison ML, Buchanan RA, Leon RV, Liu CT, Green BA, Liaw PK, Horton JA. The electrochemical evaluation of a Zr-based bulk metallic glass in a phosphate-buffered saline electrolyte. J Biomed Mater Res A 2005; 74:430-8. [PMID: 16013063 DOI: 10.1002/jbm.a.30361] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Bulk metallic glasses (BMGs) represent an emerging class of materials with an amorphous structure and a unique combination of properties. The objectives of this investigation were to define the electrochemical behavior of a specific Zr-based BMG alloy in a physiologically relevant environment and to compare these properties to standard, crystalline biomaterials as well as other Zr-based BMG compositions. Cyclic-anodic-polarization studies were conducted with a Zr52.5Cu17.9Ni14.6Al10.0Ti5.0 (at %) BMG in a phosphate-buffered saline electrolyte with a physiologically relevant oxygen content at 37 degrees C. The results were compared to three common, crystalline biomaterials: CoCrMo, 316L stainless steel, and Ti-6Al-4V. The BMG alloy was found to have a lower corrosion penetration rate (CPR), as compared to the 316L stainless steel, and an equivalent CPR, as compared to the CoCrMo and Ti-6Al-4V alloys. Furthermore, the BMG alloy demonstrated better localized corrosion resistance than the 316L stainless steel. However, the localized corrosion resistance of the BMG alloy was not as high as those of the CoCrMo and Ti-6Al-4V alloys in the tested environment. The excellent electrochemical properties demonstrated by the BMG alloy are combined with a low modulus and unparalleled strength. This unique combination of properties dramatically demonstrates the potential for amorphous alloys as a new generation of biomaterials.
Collapse
Affiliation(s)
- M L Morrison
- Department of Materials Science and Engineering, The University of Tennessee, 434 Dougherty Engineering Building, Knoxville, Tennessee 37996-2200, USA.
| | | | | | | | | | | | | |
Collapse
|
6
|
Abstract
STUDY DESIGN Retrospective review. OBJECTIVE Evaluate the clinical outcome of surgical intervention for post-traumatic syringomyelia. INTRODUCTION Progressive post-traumatic cystic myelopathy (PPCM), or syringomyelia, can occur after spinal cord injury. The authors present their surgical treatment protocol and treatment outcome of a series of patients with post-traumatic syringomyelia. METHODS The medical records of 53 patients with PPCM undergoing surgical treatment were reviewed. Laminectomies and intraoperative ultrasonography were performed. For patients with no focal tethering and only a confluent cyst on ultrasonography, a syringosubarachnoid shunt (stent) was inserted. For patients with both tethering and a confluent cord cyst, an untethering procedure was performed first. When a cyst showed significant size reduction (>50%) after untethering, no shunt was placed. When the cyst size persisted on ultrasonographic images, a short syringosubarachnoid shunt was used. The mean follow-up was 23.9 months for the 45 patients available for follow-up (range 12-102 months). RESULTS The interval between the causative event and the operation was from 5 months to 37 years (mean 6.5 years). Pain was the most frequent manifestation, followed by motor deterioration and spasticity. Postoperative improvements in >50% of the patients were noted in those presenting with worsening motor function or spasticity. In 19 of 28 patients with associated tethered spinal cord, untethering alone caused significant collapse of the cyst. Postoperative MRI demonstrated cyst collapse in 95% of the patients with untethering alone and 93% of the patients with a syringosubarachnoid shunt. CONCLUSION Post-traumatic syringomyelia can occur with or without cord tethering. Untethering alone for patients with cord tethering and cyst formation can reduce cyst size and alleviate the symptoms and signs of syringomyelia in the majority of these cases. Untethering with expansion of subarachnoid space with an expansile duraplasty may be a more physiologic way of treating a tethered cord with associated syringomyelia, i.e., treating the cause rather than the result.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami School of Medicine, 1095 NW 14th Terrace, D4-6, Miami, Florida 33136, USA.
| | | | | | | |
Collapse
|
7
|
Calancie B, Harris W, Brindle GF, Green BA, Landy HJ. Threshold-level repetitive transcranial electrical stimulation for intraoperative monitoring of central motor conduction. J Neurosurg 2001; 95:161-8. [PMID: 11599831 DOI: 10.3171/spi.2001.95.2.0161] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The authors conducted a study to evaluate repetitive transcranial electrical stimulation (TES) to assess spinal cord motor tract function in individuals undergoing spine surgery, with emphasis on safety and efficacy. METHODS Somatosensory evoked potentials (SSEPs) were elicited using standard technique. Muscle electromyographic values were measured in response to a three- or four-pulse train of stimulation delivered to the motor cortex via subdermal electrodes. They also evaluated whether changes in the minimum stimulus intensity (that is, threshold level) needed to elicit a response from a given muscle predict motor status immediately postoperatively, as well as whether changes in SSEP response amplitude and latency predict sensory status immediately postoperatively. Anesthesia was routinely induced with intravenous propofol and remifentanil, supplemented with inhaled nitrous oxide. Use of neuromuscular block was avoided after intubation. Satisfactory monitoring of muscle response to threshold-level repetitive TES was achieved in all but nine of the 194 patients studied. In contrast, cortical SSEP responses could not be elicited in 42 of 194 individuals. In cases in which responses were present, TES-based evoked responses proved to be extremely accurate for predicting postoperative motor status. Somatosensory evoked potential monitoring was nearly as accurate for predicting postoperative sensory status. There were frequent instances of postoperative motor or sensory deficit that were not predicted by SSEP- and TES-based monitoring, respectively. There were no adverse events attributable to TES-based monitoring, although since this study ended we have had a single adverse event attributable to threshold-level repetitive TES. CONCLUSIONS Intraoperative threshold-level repetitive TES-based monitoring of central motor conduction has proven to be a simple, safe, and highly accurate technique for the prevention or minimization of inadvertent motor deficit during surgery involving the spine or spinal cord.
Collapse
Affiliation(s)
- B Calancie
- The Miami Project to Cure Paralysis, University of Miami School of Medicine, Florida, USA.
| | | | | | | | | |
Collapse
|
8
|
Kemmer G, Reilly TJ, Schmidt-Brauns J, Zlotnik GW, Green BA, Fiske MJ, Herbert M, Kraiss A, Schlör S, Smith A, Reidl J. NadN and e (P4) are essential for utilization of NAD and nicotinamide mononucleotide but not nicotinamide riboside in Haemophilus influenzae. J Bacteriol 2001; 183:3974-81. [PMID: 11395461 PMCID: PMC95280 DOI: 10.1128/jb.183.13.3974-3981.2001] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Haemophilus influenzae has an absolute requirement for NAD (factor V) because it lacks almost all the biosynthetic enzymes necessary for the de novo synthesis of that cofactor. Factor V can be provided as either nicotinamide adenosine dinucleotide (NAD), nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) in vitro, but little is known about the source or the mechanism of uptake of these substrates in vivo. As shown by us earlier, at least two gene products are involved in the uptake of NAD, the outer membrane lipoprotein e (P4), which has phosphatase activity and is encoded by hel, and a periplasmic NAD nucleotidase, encoded by nadN. It has also been observed that the latter gene product is essential for H. influenzae growth on media supplemented with NAD. In this report, we describe the functions and substrates of these two proteins as they act together in an NAD utilization pathway. Data are provided which indicate that NadN harbors not only NAD pyrophosphatase but also NMN 5'-nucleotidase activity. The e (P4) protein is also shown to have NMN 5'-nucleotidase activity, recognizing NMN as a substrate and releasing NR as its product. Insertion mutants of nadN or deletion and site-directed mutants of hel had attenuated growth and a reduced uptake phenotype when NMN served as substrate. A hel and nadN double mutant was only able to grow in the presence of NR, whereas no uptake of NMN was observed.
Collapse
Affiliation(s)
- G Kemmer
- Zentrum für Infektionsforschung, Universität Würzburg, 97070 Würzburg, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Zhang Y, Masi AW, Barniak V, Mountzouros K, Hostetter MK, Green BA. Recombinant PhpA protein, a unique histidine motif-containing protein from Streptococcus pneumoniae, protects mice against intranasal pneumococcal challenge. Infect Immun 2001; 69:3827-36. [PMID: 11349048 PMCID: PMC98401 DOI: 10.1128/iai.69.6.3827-3836.2001] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The multivalent pneumococcal conjugate vaccine is effective against both systemic disease and otitis media caused by serotypes contained in the vaccine. However, serotypes not covered by the current conjugate vaccine may still cause pneumococcal disease. To address these serotypes and the remaining otitis media due to Streptococcus pneumoniae, we have been evaluating antigenically conserved proteins from S. pneumoniae as vaccine candidates. A previous report identified a 20-kDa protein with putative human complement C3-proteolytic activity. By utilizing the publicly released pneumococcal genomic sequences, we found the gene encoding the 20-kDa protein to be part of a putative open reading frame of approximately 2,400 bp. We recombinantly expressed a 79-kDa fragment (rPhpA-79) that contains a repeated HxxHxH motif and evaluated it for vaccine potential. The antibodies elicited by the purified rPhpA-79 protein were cross-reactive to proteins from multiple strains of S. pneumoniae and were against surface-exposed epitopes. Immunization with rPhpA-79 protein adjuvanted with monophosphoryl lipid A (for subcutaneous immunization) or a mutant cholera toxin, CT-E29H (for intranasal immunization), protected CBA/N mice against death and bacteremia, as well as reduced nasopharyngeal colonization, following intranasal challenge with a heterologous pneumococcal strain. In contrast, immunization with the 20-kDa portion of the PhpA protein did not protect mice. These results suggest that rPhpA-79 is a potential candidate for use as a vaccine against pneumococcal systemic disease and otitis media.
Collapse
Affiliation(s)
- Y Zhang
- Department of Immunology, Wyeth Lederle Vaccines, West Henrietta, New York 14586-9728, USA.
| | | | | | | | | | | |
Collapse
|
10
|
Abstract
Haemophilus influenzae lipoprotein e (P4) is a member of the DDDD phosphohydrolase superfamily and mediates heme transport. Each of the aspartate residues of the signature motif is required for phosphomonoesterase activity, as none of the e (P4) single D mutants (D64A, D66A, D181N, and D185A) possessed detectable phosphomonoesterase activity. These results suggest that the signature motif is essential to the phosphomonoesterase activity of lipoprotein e (P4). When assessed for phosphomonoesterase-dependent heme transport activity in Escherichia coli hemA strains, plasmids containing D181N and D185A retained heme transport as indicated by aerobic growth while D64A and D66A did not. We conclude that phosphomonoesterase activity is not required for heme transport.
Collapse
Affiliation(s)
- T J Reilly
- Department of Molecular Microbiology and Imunology, University of Missouri Medical School, Columbia, MO 65212, USA
| | | | | | | |
Collapse
|
11
|
Razack N, Green BA, Levi AD. The management of traumatic cervical bilateral facet fracture-dislocations with unicortical anterior plates. J Spinal Disord 2000; 13:374-81. [PMID: 11052345 DOI: 10.1097/00002517-200010000-00002] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The goal of this study was to evaluate single-level anterior cervical discectomy and stabilization for bilateral facet fracture dislocations using bone graft and anterior titanium plates with unicortical screw fixation in the clinical setting. We conducted a retrospective review during a consecutive 6-year period of patients treated in a single institution for traumatic single-level cervical bilateral facet fracture-dislocation. All fracture-dislocations that could be aligned with traction were subsequently stabilized using an anterior cervical discectomy with bone graft and titanium unicortical locking plates. All patients were examined after operation for radiographic evidence of healing and neurologic outcome. Twenty-two patients (M:F ratio, 16:6; average age, 47.7 years) underwent an anterior cervical discectomy and stabilization with either an allograft (n = 12) or an autograft (n = 10) and a titanium unicortical locking plate. Most patients had sustained a spinal cord injury (87%) or a radicular injury (9%). The average follow-up was 32 months, with a minimum follow-up of 1 year (range, 13 to 77 months). There was one instrumentation-related failure, but all 22 patients ultimately had evidence of stability at the instrumented level on the final follow-up examination. Anterior fixation with unicortical cervical locking plates as a single procedure offers an excellent surgical alternative in the management of many cervical bilateral facet fracture dislocations in patients who can be reduced preoperatively.
Collapse
Affiliation(s)
- N Razack
- Department of Neurological Surgery, University of Miami School of Medicine, Jackson Memorial Hospital, Florida, USA
| | | | | |
Collapse
|
12
|
Abstract
OBJECTIVE Biplanar fluoroscopic imaging linked to a computer-driven mechanical end-effector is under development as a targeting system for spinal surgery. This technology has the potential to enhance standard intraoperative fluoroscopic information for localization of the pedicle entry point and trajectory, and it may be an effective alternative to the computed tomography-based image-guided system (IGS) in pedicle screw placement. A preclinical study to assess the accuracy and time efficiency of this system versus a conventional IGS was conducted. METHODS Pedicle screw placement was performed in six cadavers from T1 to S1 levels using the ViewPoint IGS (Picker International, Inc., Cleveland, OH) on one side versus the Fluorotactic guidance system (Z-Kat, Inc., Miami, FL) on the other side. Of 216 possible pedicles, 208 were instrumented; 8 pedicle diameters were too small or were not adequately imaged. Postinsertion, each pedicle was assessed for the presence and location of cortical perforation using computed tomographic scanning and direct visualization. RESULTS The number of successful screw placements was 89 (87.3%) of 102 for IGS and 87 (82.1 %) of 106 for the Fluorotactic guidance system, respectively. The mean time to register and operate on one level using the Fluorotactic guidance system was 14:34 minutes (minutes:seconds), compared with 6:50 minutes using the IGS. The average fluoroscope time was 4.6 seconds per pedicle. CONCLUSION Our data indicate that this first-generation fluoroscopy-based targeting system can significantly assist the surgeon in pedicle screw placement. The overall accuracy is comparable to an IGS, especially in the region of T9-L5. A second-generation system with a faster end-effector and user-friendly interface should significantly reduce the operating and fluoroscope time.
Collapse
Affiliation(s)
- W W Choi
- Department of Neurosurgery and the Miami Project to Cure Paralysis, Jackson Memorial Hospital, University of Miami, Florida, USA
| | | | | |
Collapse
|
13
|
|
14
|
Tebbey PW, Scheuer CA, Peek JA, Zhu D, LaPierre NA, Green BA, Phillips ED, Ibraghimov AR, Eldridge JH, Hancock GE. Effective mucosal immunization against respiratory syncytial virus using purified F protein and a genetically detoxified cholera holotoxin, CT-E29H. Vaccine 2000; 18:2723-34. [PMID: 10781860 DOI: 10.1016/s0264-410x(00)00058-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We exploited the powerful adjuvant properties of cholera holotoxin (CT) to create a mucosally administered subunit vaccine against respiratory syncytial virus (RSV). A genetically detoxified mutant CT with an E to H substitution at amino acid 29 of the CT-A1 subunit (CT-E29H) was compared to wild type CT for toxicity and potential use as an intranasal (IN) adjuvant for the natural fusion (F) protein of RSV. When compared to CT the results demonstrated that: (1) CT-E29H binding to GM1 ganglioside was equivalent, (2) ADP-ribosylation of agmatine was 11.7%, and (3) toxicity was attenuated in both Y-1 adrenal (1.2%) and patent mouse gut weight assays. IN vaccination with F protein formulated with CT-E29H induced serum anti-CT and anti-F protein antibodies that were comparable to those obtained after vaccination with equivalent doses of CT. Vaccinations containing CT-E29H at doses of 0.1 microg were statistically equivalent to 1.0 microg in enhancing responses to F protein. Antigen-specific mucosal IgA and anti-RSV neutralizing antibodies were detected in nasal washes and sera, respectively, of mice that had received F protein and 0.1 or 1.0 microg of CT-E29H. Anti-F protein IgA was not detected in the nasal washes from mice IN vaccinated with 0.01 microg CT-E29H or IM with F protein adsorbed to AlOH adjuvant. In addition, the formulation of purified F protein and CT-E29H (0.1 and 1.0 microg) facilitated protection of both mouse lung and nose from live RSV challenge. Collectively, the data have important implications for vaccine strategies that use genetically detoxified mutant cholera holotoxins for the mucosal delivery of highly purified RSV antigens.
Collapse
Affiliation(s)
- P W Tebbey
- Department of Immunology Research, Wyeth-Lederle Vaccines, 211 Bailey Road, West Henrietta, NY 14586-9728, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Zagursky RJ, Ooi P, Jones KF, Fiske MJ, Smith RP, Green BA. Identification of a Haemophilus influenzae 5'-nucleotidase protein: cloning of the nucA gene and immunogenicity and characterization of the NucA protein. Infect Immun 2000; 68:2525-34. [PMID: 10768940 PMCID: PMC97455 DOI: 10.1128/iai.68.5.2525-2534.2000] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report on the identification of a surface-exposed, highly conserved, immunogenic nontypeable Haemophilus influenzae (NTHi) protein, which elicits cross-reactive bactericidal antibodies against NTHi. The protein was extracted from NTHi strain P860295 with KSCN and purified; it migrated as a single band on a sodium dodecyl sulfate-polyacrylamide gel with an apparent molecular mass of 63 kDa. Mouse antiserum generated against the purified protein was reactive on whole-cell enzyme-linked immunosorbent assay (ELISA) with seven NTHi strains and type b Eagan and Whittier strains and exhibited bactericidal activity to homologous and heterologous NTHi strains. However, the protein is made in small amounts in NTHi as corroborated by immunoelectron microscopy. To further study this protein, we cloned, sequenced, and expressed it recombinantly in Escherichia coli. The recombinant protein is localized in the periplasm of E. coli and has been purified to homogeneity. Both the recombinant and native proteins possess 5'-nucleotidase activity; hence, the protein has been called NucA. Mouse antiserum directed against the recombinant NucA protein was reactive on Western immunoblots and whole-cell ELISA with all H. influenzae strains tested including Eagan and was bactericidal for two heterologous strains tested. The antiserum also resulted in a log reduction in bacteremia, in an infant-rat protection study with H. influenzae type b as the challenge strain. These features suggest that NucA is a potential subunit vaccine candidate against NTHi disease.
Collapse
Affiliation(s)
- R J Zagursky
- Wyeth-Lederle Vaccines, West Henrietta, New York 14586, USA.
| | | | | | | | | | | |
Collapse
|
16
|
Gleaves DH, Lowe MR, Snow AC, Green BA, Murphy-Eberenz KP. Continuity and discontinuity models of bulimia nervosa: a taxometric investigation. J Abnorm Psychol 2000. [PMID: 10740936 DOI: 10.1037//0021-843x.109.1.56] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Past research evaluating the continuity and discontinuity models of bulimia has produced inconclusive results. In the current study, we performed a taxometric analysis of bulimia nervosa using means above minus below a sliding cut and maximum covariance analysis with a sample of women diagnosed with bulimia nervosa (n = 201) or women college students (n = 412). Indicators were derived from the Bulimia Test--Revised and the Eating Attitudes Test--26, and both a mixed sample and the nonclinical sample were analyzed. With both taxometric methods and both mixed and nonclinical samples, results were consistently suggestive of a latent taxon for bulimia. These results challenge a dimensional model of bulimia nervosa.
Collapse
Affiliation(s)
- D H Gleaves
- Department of Psychology, Texas A&M University, College Station 77842-4235, USA.
| | | | | | | | | |
Collapse
|
17
|
Abstract
OBJECT Progressive posttraumatic cystic myelopathy (PPCM) can occur after an injury to the spinal cord. Traditional treatment of PPCM consists of inserting a shunt into the cyst. However, some authors have advocated a more pathophysiological approach to this problem. The authors of the present study describe their surgical treatment protocol and outcome in a series of patients with syringomyelia. METHODS Medical records of 34 patients undergoing surgical treatment for PPCM were reviewed. Laminectomies and intraoperative ultrasonography were performed. In patients without focal tethering of the spinal cord and in whom only a confluent cyst had been revealed on ultrasonography, a syringosubarachnoid shunt was inserted; in those with both tethering and a confluent cord cyst, an untethering procedure was performed first. When a significant reduction (>50%) in the size of the cyst was shown after the untethering procedure, no shunt was inserted. When no changes in cyst size were demonstrated on ultrasonography, a short syringosubarachnoid shunt was used. The mean follow-up period was 28.7 months (range 12-102 months). The interval between the mechanism of injury and the operation ranged from 5 months to 37 years (mean 11 years). Pain was the most frequent symptom, which was followed by motor deterioration and spasticity. Postoperative improvement was noted in 55% of patients who experienced motor function deterioration and in 53% of those who demonstrated worsening spasticity. In 14 of 18 patients with an associated tethered spinal cord, tethering alone caused significant collapse of the cyst. Postoperative magnetic resonance imaging demonstrated cyst collapse in 92% of patients who had undergone untethering alone and in 93% of those who underwent syringosubarachnoid shunt placement. Treatment failure was observed in 7% of the former group and in 13% of the latter. CONCLUSIONS Posttraumatic cystic myelopathy can occur with or without the presence of tethered cord syndrome. Intraoperative ultrasonography can readily demonstrate this distinction to aid in surgical decision making. Untethering alone in patients with tethered cord syndrome and cyst formation can reduce the cyst size and alleviate symptoms and signs of posttraumatic cystic myelopathy in the majority of these cases. Untethering procedures in which duraplasty is performed to expand the subarachnoid space may be a more physiologically effective way of treating tethered cord with associated syringomyelia.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami School of Medicine, Florida, USA.
| | | | | | | |
Collapse
|
18
|
Abstract
OBJECTIVE We examined affective and cognitive components of body image related to physical appearance, weight, and health among 120 university men and women of three racial/ethnic groups: African American, European American, and Latino/a American. METHOD Participants completed a Background Information Sheet, the Multidimensional Body-Self Relations Questionnaire (MBSRQ), the Body-Esteem Scale (BES) with additional items, and the Balanced Inventory of Desirable Responding (BIDR). We tested for effects of race/ethnicity and gender on the body image measures while controlling for age, body size, social desirability, and socioeconomic status (SES). RESULTS African Americans reported greatest body satisfaction and least overestimation of weight. Latino/a Americans were equal to or higher than European Americans on all indices. Gender differences occurred on global body image, weight concerns, fitness, and health. There were no Gender x Race/Ethnicity interactions. DISCUSSION This pattern of racial/ethnic and gender differences shows a need for exploring a wider range of culturally relevant body image dimensions.
Collapse
Affiliation(s)
- K J Miller
- Department of Psychology, Philadelphia College of Osteopathic Medicine, Philadelphia, PA 19131-1693, USA.
| | | | | | | | | | | |
Collapse
|
19
|
Gleaves DH, Lowe MR, Snow AC, Green BA, Murphy-Eberenz KP. Continuity and discontinuity models of bulimia nervosa: a taxometric investigation. J Abnorm Psychol 2000; 109:56-68. [PMID: 10740936 DOI: 10.1037/0021-843x.109.1.56] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Past research evaluating the continuity and discontinuity models of bulimia has produced inconclusive results. In the current study, we performed a taxometric analysis of bulimia nervosa using means above minus below a sliding cut and maximum covariance analysis with a sample of women diagnosed with bulimia nervosa (n = 201) or women college students (n = 412). Indicators were derived from the Bulimia Test--Revised and the Eating Attitudes Test--26, and both a mixed sample and the nonclinical sample were analyzed. With both taxometric methods and both mixed and nonclinical samples, results were consistently suggestive of a latent taxon for bulimia. These results challenge a dimensional model of bulimia nervosa.
Collapse
Affiliation(s)
- D H Gleaves
- Department of Psychology, Texas A&M University, College Station 77842-4235, USA.
| | | | | | | | | |
Collapse
|
20
|
Affiliation(s)
- E D Schwartz
- Department of Radiology, University of Miami School of Medicine, FL 33136, USA
| | | | | | | |
Collapse
|
21
|
Lee TT, Green BA, Dietrich WD, Yezierski RP. Neuroprotective effects of basic fibroblast growth factor following spinal cord contusion injury in the rat. J Neurotrauma 1999; 16:347-56. [PMID: 10369555 DOI: 10.1089/neu.1999.16.347] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cytokines and neurotrophic factors have been implicated in the pathophysiology of injury to the central nervous system. While some cytokines are considered pro-inflammatory, other factors promote neuronal growth and survival. The present study investigated the neuroprotective effects of interleukins 1 (IL-1), 4 (IL-4), and 6 (IL-6), nerve growth factor (NGF), ciliary neurotrophic factor (CNTF), and basic fibroblast growth factor (bFGF) in a contusion model of spinal cord injury. Female Sprague-Dawley rats (n = 55) sustained a 10-g weight-drop injury to the lower thoracic spinal cord (T10) from a height of 12.5 mm using the NYU impactor. A micro-infusion system (Alzet minipump) was used to continuously deliver drugs or vehicle directly into the epicenter of the contused spinal cord starting 1 or three h postinjury. At the end of 7 days, animals were perfused and the cords removed for histopathological analysis. Longitudinal serial sections were cut on a freezing microtome and stained with cresyl violet. Areas of central necrosis, partial preservation, and total zone of tissue injury were identified and traced by an independent reviewer using a computer based imaging system. The mean total zone of injury in five animals receiving vehicle infusion was 18.04+/-4.20 mm3. The mean zone of partial preservation in these animals was 16.46+/-3.32 mm. Basic fibroblast growth factor reduced the total zone of injury by 33% [p<0.01, least significant difference (LSD) of Fisher] in five animals and the zone of partial preservation by 32% (p<0.01, LSD of Fisher) when compared to controls. There were trends toward reduction in total zone of injury and zone of partial preservation in rats treated with IL-4, CNTF, and NGF versus vehicle; however, none of these reached statistical significance. No significant differences were observed between animals receiving vehicle versus bFGF treatment commencing 3 h after injury. These data demonstrate that the continuous intramedullary infusion of bFGF initiated one hour after moderate contusion injury of the spinal cord significantly reduces the total zone of injury and the zone of partial preservation. These results support the further investigation and possible future clinical application of bFGF in the treatment of acute spinal cord contusion injury.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery and The Miami Project to Cure Paralysis, University of Miami School of Medicine, Florida, USA.
| | | | | | | |
Collapse
|
22
|
Tolaymat LL, Brown TL, Maher JE, Horan CA, Green BA, Ripps BA. Reproductive potential after methotrexate treatment of ectopic gestation in a community hospital. J Reprod Med 1999; 44:335-8. [PMID: 10319302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
OBJECTIVE To compare the rates of ipsilateral tubal patency after methotrexate treatment versus conservative surgical treatment in a small community hospital lacking personnel dedicated to methotrexate management. STUDY DESIGN From hospital and clinic records, cases of ectopic gestation within a six-year interval were identified. Method of treatment and location of the ectopic gestation were documented by review of records and confirmed by patient interviews. Women desiring fertility were offered hysterosalpingography (HSG) to evaluate tubal patency. HSG was performed under fluoroscopy with water-soluble contrast medium. RESULTS HSG was completed in 11 cases of linear salpingostomy and 11 cases of ectopic gestations treated by methotrexate. Ipsilateral patency was documented in 8 of 11 (72%) tubes treated by linear salpingostomy and 9 of 11 (81%) methotrexate-treated tubes. One methotrexate case had a prior ipsilateral ectopic treated by salpingostomy, and two additional cases had a prior contralateral ectopic removed by salpingectomy. Each of these three cases had ipsilateral tubal patency after methotrexate for the most recent ectopic gestation. CONCLUSION Data from this study suggest comparable tubal patency rates after methotrexate and conservative surgery. Comparable tubal patency outcomes were obtained in our community hospital despite a less-rigorous-than normal follow-up protocol.
Collapse
Affiliation(s)
- L L Tolaymat
- Department of Obstetrics and Gynecology, University of Florida at Pensacola 32504, USA
| | | | | | | | | | | |
Collapse
|
23
|
Finitsis SN, Falcone S, Green BA. MR of the spine in the presence of metallic bullet fragments: is the benefit worth the risk? AJNR Am J Neuroradiol 1999; 20:354-6. [PMID: 10094370 PMCID: PMC7056092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
|
24
|
Abstract
STUDY DESIGN A retrospective review of a clinical series. OBJECTIVE To evaluate the use of a rigid cervical collar alone as the treatment for stable Jefferson fracture, and to devise an algorithm for treatment of Jefferson fracture with or without an associated cervical injury. SUMMARY OF BACKGROUND DATA The traditional treatment for Jefferson fracture, if there is no indication for surgery, is immobilization by halo vest. Because halo vest placement is associated with intracranial infection and a significant degree of patient discomfort, slightly less rigid forms of external immobilization may be useful for the treatment of stable Jefferson fractures. No standard protocol calling for the use of one form of stabilization device has been reported. MATERIALS The medical records and radiographs of 16 consecutive patients with Jefferson fracture during a 2-year period were reviewed. Each patient underwent a complete cervical radiograph series and a computed tomographic scan. The mean C1 lateral mass displacement was 1.8 mm. Cervical spine radiographs, including lateral flexion-extension views were obtained 10 to 12 weeks after injury before the removal of an external immobilization device. RESULTS Of these 16 patients, 1 sustained a complete injury, and 7 sustained an incomplete injury. Eight patients were neurologically intact. Twelve patients sustained a stable Jefferson fracture and were treated with a rigid cervical collar (Miami-J collar [Jerome Medical, Moorestown, NJ]) alone from 10 to 12 weeks. The patient sustaining the complete neurologic injury died of multisystem trauma. All 15 live patients showed no instability on their follow-up plain radiographs before the removal of an external stabilization device. Six patients underwent further plain radiographs approximately 1 year after the fracture and similarly demonstrated no instability. CONCLUSIONS Isolated stable burst fracture of the atlas can be treated effectively with a rigid cervical collar alone for 10 to 12 weeks with good neurologic recovery and segmental stability. Unstable Jefferson fractures with concurrent unstable fracture of other cervical vertebrae, especially C2, requires surgical stabilization.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami School of Medicine, Florida, USA.
| | | | | |
Collapse
|
25
|
Abstract
OBJECTIVE The number of geriatric patients seeking surgical treatment for cervical myelopathy is steadily increasing. Although anecdotal experiences have been good, insufficient data exists in the spine literature concerning this particular group. We decided to review our experience to determine efficacy of surgical management and examine our morbidity with this select group. METHODS We undertook a retrospective review of all surgical procedures for nontraumatic cervical myelopathy performed at Mt Sinai Medical Center and Jackson Memorial Medical Center between January 1 1987 and June 1 1992, in patients older than 70 years of age (33 men and 18 women). RESULTS A total of 53 cervical surgical procedures were performed in 51 patients (nine expansile laminoplasties, 20 anterior cervical diskectomies and fusion and 24 decompressive posterior laminectomies). The average hospital stay was 7.7 +/- 3.4 days. Twenty-one (41%) patients required inpatient rehabilitation; the remaining 30 patients received outpatient rehabilitative therapy. The major morbidity rate was 3.9%, and the minor morbidity rate was 5.8%. Perioperative medical complications included cardiac arrhythmias, hypertensive episodes, atelectasis, confusion, urinary dysfunction and hyponatremia. All of these complications resolved except in one patient. The perioperative mortality rate was 2%. Office follow-up was performed for a mean of 11.1 +/- 2.5 months postoperatively. Comparison of preoperative and postoperative functional status was performed using Nurick's criteria as described in the literature. At follow-up, 60.8% of the patients had improvement in their myelopathic symptoms, especially in regard to gait; 33.3% were stabilized and 5.9% had worsened neurological function. CONCLUSION This study demonstrates that corrective surgical procedures for significant nontraumatic cervical myelopathy in the geriatric population may be performed safely, that is, with acceptable risk of morbidity and reasonable expectation for clinical improvement.
Collapse
Affiliation(s)
- N Razack
- Department of Neurological Surgery, University of Miami School of Medicine, Florida, USA
| | | | | |
Collapse
|
26
|
Abstract
INTRODUCTION With the advances in microsurgical and monitoring techniques, spinal ependymomas are gross totally resected more frequently. The use of adjuvant radiotherapy has become questionable with gross total resection and its role for residual neoplasm need to be redefined. A retrospective analysis of a series of patients was carried out to investigate our clinical outcome and selected use of post-operative radiotherapy. CLINICAL MATERIALS AND METHODS Between July 1990 and May 1995, nineteen patients [M : F = 12 : 7; age range: 21 to 71 years] with a spinal ependymoma were treated at University of Miami by the senior author. (BAG) Pre-operative MRI diagnosed the intraspinal tumor, and pathology reports demonstrated that each patient had a histologically confirmed ependymoma. At the time of diagnosis, the most common symptoms presented were pain (in 16 patients = 84.2%). The pattern of progression of clinical symptoms was directly related to the location of the tumor. Each patient had an MRI immediately after surgery, approximately 6 months post-operatively, and then annually. RESULTS All 19 patients underwent intradural microsurgical exploration with an attempted gross total resection (achieved in 16 patients = 79%) of the ependymoma through a posterior approach. Direct neural tissue stimulation halted further resection in 2 patients with questionable tumor margins. Radiation therapy was employed as a surgical adjunct in 3 patients (15.8%) because of possible residual tumor. All patients were followed up postoperatively for an average of 50.6 months (range 6 months to 6 years). All patients are surviving to date. Surgical resection of these tumors led to significant alleviation of pre-operative symptom. There has been no radiographic evidence of tumor recurrence or growth in any patient to date. CONCLUSION Surgical resection of spinal ependymoma leads to significant improvement of pre-operative symptoms. Surgical removal alone, with an attempt to grossly resect the tumor, should be the treatment of choice, with careful clinical and radiographic follow-up. Radiation therapy should only be considered as a surgical adjunct where gross total resection is not achieved.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami School of Medicine, FL, USA
| | | | | |
Collapse
|
27
|
Abstract
OBJECTIVE A retrospective review was conducted to compare magnetic resonance (MR) and conventional spinal angiographic images and to investigate the outcome of our treatment protocol for patients with spinal dural arteriovenous fistulas (DAVFs). MATERIALS AND METHODS Nine patients with a diagnosis of DAVF based on clinical myelopathy and preoperative MR imaging (MRI) and MR angiography (MRA) findings were treated at our institution by the senior author (BAG). All nine patients initially presented with progressive myelopathy. Preoperative MRI revealed T2-weighted signal abnormalities in all patients, and MRA was diagnostic in all patients. Each patient underwent a laminectomy and ligation of the arterialized draining vein. Selective spinal angiograms were used to confirm the level of fistula immediately before the surgical procedure was performed and to document complete obliteration after clip ligation of the medullary draining vein. Follow-up MRI and MRA were performed approximately 2 months postoperatively. RESULTS MRI T2-weighted signal hyperintensity improved after surgery in all nine patients. Postoperatively, progression of motor weakness and gait difficulty was halted and some improvement was observed in all patients. No patient was neurologically normal, however. To date, there has been no clinical or MRA evidence of recurrence in any patient. CONCLUSION Preoperative MRA and intraoperative spinal x-ray angiography present as an effective combination for diagnosing and intraoperatively confirming DAVF. Both T1-weighted enhancement and T2-weighted signal hyperintensity on MR images improved after the obliteration of the DAVFs and correlated with clinical improvement in all nine patients. MRA provides adequate visualization and localization of spinal DAVFs and may serve as a useful noninvasive tool for diagnosing and following patients with spinal DAVFs in the future.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami School of Medicine, Florida 33101, USA
| | | | | | | |
Collapse
|
28
|
Nash MS, Jacobs PL, Klerk KM, Green BA. Oxyhemoglobin desaturation and aberrant carbon dioxide homeostasis during electrically stimulated exercise in a ventilator-dependent tetraplegic patient. Arch Phys Med Rehabil 1998; 79:873-6. [PMID: 9685107 DOI: 10.1016/s0003-9993(98)90372-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This single-subject case examined oxyhemoglobin saturation and alveolar end-tidal carbon dioxide levels in a ventilator-dependent tetraplegic patient undergoing electrical stimulation cycle ergometry. When exercising with a closed tracheostomy cuff under resting ventilator settings (resting intermittent mandatory ventilation; frequency = 6breaths/min, tidal volume = 83.3mL, minute ventilation =5L/min), his oxyhemoglobin saturation decreased from 100% to 92%, while alveolar endtidal carbon dioxide increased linearly to 47mmHg. These undesirable changes were corrected under adjusted intermittent mandatory ventilation conditions (frequency = 12breaths/min, tidal volume = 83.3mL, minute ventilation = 10L/min), during which oxyhemoglobin saturation remained above 98% and the alveolar end-tidal carbon dioxide trend resembled that of ventilator-independent tetraplegic individuals undergoing the same exercise. Because the subject's heart rate was higher under adjusted ventilation conditions, these responses may have been caused by augmented venous return resulting from greater abdominothoracic pumping at the higher breathing frequency. These findings support the need to modify ventilator settings in ventilator-dependent tetraplegic persons while undergoing exercise to maintain oxyhemoglobin saturation and carbon dioxide homeostasis.
Collapse
Affiliation(s)
- M S Nash
- Department of Orthopaedics and Rehabilitation, The Miami Project to Cure Paralysis, University of Miami School of Medicine, Coral Gables, FL 33146, USA
| | | | | | | |
Collapse
|
29
|
Calancie B, Harris W, Broton JG, Alexeeva N, Green BA. "Threshold-level" multipulse transcranial electrical stimulation of motor cortex for intraoperative monitoring of spinal motor tracts: description of method and comparison to somatosensory evoked potential monitoring. J Neurosurg 1998; 88:457-70. [PMID: 9488299 DOI: 10.3171/jns.1998.88.3.0457] [Citation(s) in RCA: 229] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
UNLABELLED Numerous methods have been pursued to evaluate function in central motor pathways during surgery in the anesthetized patient. At this time, no standard has emerged, possibly because each of the methods described to date requires some degree of compromise and/or lacks sensitivity. OBJECT The goal of this study was to develop and evaluate a protocol for intraoperative monitoring of spinal motor conduction that: 1) is safe; 2) is sensitive and specific to motor pathways; 3) provides immediate feedback; 4) is compatible with anesthesia requirements; 5) allows monitoring of spontaneous and/or nerve root stimulus-evoked electromyography; 6) requires little or no involvement of the surgical team; and 7) requires limited equipment beyond that routinely used for somatosensory evoked potential (SSEP) monitoring. Using a multipulse electrical stimulator designed for transcranial applications, the authors have developed a protocol that they term "threshold-level" multipulse transcranial electrical stimulation (TES). METHODS Patients considered at high risk for postoperative deficit were studied. After anesthesia had been induced and the patient positioned, but prior to incision, "baseline" measures of SSEPs were obtained as well as the minimum (that is, threshold-level) TES voltage needed to evoke a motor response from each of the muscles being monitored. A brief, high-frequency pulse train (three pulses; 2-msec interpulse interval) was used for TES in all cases. Data (latency and amplitude for SSEP; threshold voltage for TES) were collected at different times throughout the surgical procedure. Postoperative neurological status, as judged by evaluation of sensory and motor status, was compared with intraoperative SSEP and TES findings for determination of the sensitivity and specificity of each electrophysiological monitoring technique. Of the 34 patients enrolled, 32 demonstrated TES-evoked responses in muscles innervated at levels caudal to the lesion when examined after anesthesia induction and positioning but prior to incision (that is, baseline). In contrast, baseline SSEPs could be resolved in only 25 of the 34 patients. During surgery, significant changes in SSEP waveforms were noted in 12 of these 25 patients, and 10 patients demonstrated changes in TES thresholds. Fifteen patients experienced varying degrees and durations of postoperative neurological deficit. Intraoperative changes in TES thresholds accurately predicted each instance of postoperative motor weakness without error, but failed to predict four instances of postoperative sensory deficit. Intraoperative SSEP monitoring was not 100% accurate in predicting postoperative sensory status and failed to predict five instances of postoperative motor deficit. As a result of intraoperative TES findings, the surgical plan was altered or otherwise influenced in six patients (roughly 15% of the sample population), possibly limiting the extent of postoperative motor deficit experienced by these patients. CONCLUSIONS This novel method for intraoperative monitoring of spinal motor conduction appears to meet all of the goals outlined above. Although the risk of postoperative motor deficit is relatively low for the majority of spine surgeries (for example, a simple disc), high-risk procedures, such as tumor resection, correction of vascular abnormalities, and correction of major deformities, should benefit from the virtually immediate and accurate knowledge of spinal motor conduction provided by this new monitoring approach.
Collapse
Affiliation(s)
- B Calancie
- The Miami Project to Cure Paralysis and the Department of Neurological Surgery, University of Miami School of Medicine, Florida 33136, USA
| | | | | | | | | |
Collapse
|
30
|
Lee TT, Green BA, Gromelski EB. Safety and stability of open-door cervical expansive laminoplasty. J Spinal Disord 1998; 11:12-5. [PMID: 9493764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cervical expansive laminoplasty has been utilized for over 20 years. This retrospective analysis investigated the safety and incidence of postoperative instability of patients undergoing a modified expansive laminoplasty. One hundred five patients underwent a modified cervical expansive laminoplasty and had at least a 6-month follow-up. These 105 patients were followed for a mean of 18.6 months (range 6-89 months). All patients remained in a rigid cervical collar for 8-12 weeks after the laminoplasty. Postoperative cervical plain radiographs were obtained on postoperative day 1, an average of 9.6 weeks postoperatively (range 8-12 weeks) and an average of 10.1 months (range 6-12 months) postoperatively. Thirty-five patients underwent further radiographs >18 months postoperatively. Laminoplasty was performed in 82 patients with progressive cervical spondylotic myelopathy, 4 patients with ossification of the posterior longitudinal ligament, 7 patients for posterior approach to a cervical neoplasm, and 12 patients for early posttraumatic decompression. The canal/vertebral body ratio showed a significant increase from 0.78 to 1.02 (paired t test, p < 0.001). Postoperatively, no incidence of graft dislodgement or segmental instability was diagnosed in any patient. Modified open-door expansive laminoplasty is an effective way of expanding the spinal canal. Its associated low incidence of postoperative instability and kyphotic deformity should make this procedure a desirable substitute for cervical laminectomy under many circumstances.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami School of Medicine, Florida 33101, USA
| | | | | |
Collapse
|
31
|
Lee TT, Aldana PR, Kirton OC, Green BA. Follow-up computerized tomography (CT) scans in moderate and severe head injuries: correlation with Glasgow Coma Scores (GCS), and complication rate. Acta Neurochir (Wien) 1998; 139:1042-7; discussion 1047-8. [PMID: 9442218 DOI: 10.1007/bf01411558] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The wide availability of computerized tomography (CT) scan has popularized its use in initial and follow-up evaluations of head trauma patients. Follow-up CT scans of clinically stable patients, however, may not provide additional information, but could potentially subject the patients to secondary injuries. The authors investigated the correlation between CT scans and Glasgow coma score (GCS), and complication rate during follow-up CT scans in an attempt to dissuade clinicians from obtaining unnecessary follow-up CT scans. METHODS The medical records of 180 patients with blunt head trauma were retrospectively reviewed. Only patients (117) with moderate and severe head injuries were included in the study. A total of 319 follow-up brain CT's for 94 patients were obtained. RESULTS The change in CT scans was compared to the GCS the day of the scan. These two variables were found to be positively correlated by Chi-square analysis (chi 2 = 81.2; alpha < 0.001). CPP trend was found also be correlated with CT scan evolution by the Chi-square analysis (alpha < 0.001). When patients had unchanged or improved GCS, 73.1% had improved or the same CT appearance. When patients had a worse GCS, the CT was worse in 77.9%. A 16.9% (54/319) complication rate was documented during the follow-up scans (hemodynamic instability, increased intracranial pressure, desaturation, and agitation). This rate was higher in severe head trauma (GCS 3-8) patients than in moderate head injury (GCS 9-12) patients. Hemodynamic instability was the most common complication, which comprises 42.6% (23/54) of all complications. CONCLUSION Because of the correlation between the CT scan appearance and the clinical status, as well as the detrimental effect of mobilizing critically ill patients, the authors urge the use of follow-up CT scans only in patients with clinical deterioration unexplained by ICP changes alone.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami, FL, USA
| | | | | | | |
Collapse
|
32
|
Abstract
Development of delayed or recurrent intracranial hematomas requiring reexploration or a secondary craniotomy is well known. Patients with bilateral pathology requiring bilateral craniotomies as the initial emergency operative intervention, however, are uncommon. The lack of available literature and the large volume of head trauma seen at our institution prompted us to analyze the retrospective data on blunt head injury requiring bilateral craniotomies. Twenty patients underwent bilateral craniotomies at the University of Miami/Jackson Memorial Medical Center between January 1986 and June 1994. Ages ranged from 18 to 85 years. Mechanism of injury included motor vehicle crash (n = 4), pedestrian hit by automobile (n = 4), assault (n = 8), fall from height (n = 3), and unknown (n = 1). Epidural hematomas, acute subdural hematomas, contusions, and intracerebral hematomas were seen in varying combinations. The preoperative Glasgow Coma Scale (GCS) score ranged from 4 to 14, with a mean of 8.8 (+/-0.82 SE). Sixteen of the 20 patients survived and were discharged from the hospital. The survivors' Rancho Los Amigos Scale score on discharge ranged from 2 to 8, with a mean of 6.1 (+/-0.45 SE). A Fisher's exact test was performed to compare the outcome between the patients with mild (GCS score 13-15) to moderate (GCS score 9-12) head injury and those with severe (GCS score 4-8) head injury. It showed a statistically higher frequency of death in the severe category (p < 0.05). In conclusion, the outcome of patients with bilateral pathology requiring emergency bilateral craniotomy at initial treatment correlated well with their GCS scores at initial presentation.
Collapse
Affiliation(s)
- N Razack
- University of Miami Department of Surgery, Jackson Memorial Medical Center, Florida, USA
| | | | | | | | | |
Collapse
|
33
|
Klose KJ, Jacobs PL, Broton JG, Guest RS, Needham-Shropshire BM, Lebwohl N, Nash MS, Green BA. Evaluation of a training program for persons with SCI paraplegia using the Parastep 1 ambulation system: part 1. Ambulation performance and anthropometric measures. Arch Phys Med Rehabil 1997; 78:789-93. [PMID: 9344294 DOI: 10.1016/s0003-9993(97)90188-x] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To describe performance parameters and effects on anthropometric measures in spinal cord injured subjects training with the Parastep 1 system. DESIGN Before-after trial. SETTING Human spinal cord injury applied research laboratory. PARTICIPANTS Thirteen men and 3 women with thoracic (T4-T11) motor-complete spinal cord injury: mean age, 28.8yrs; mean duration postinjury, 3.8yrs. INTERVENTION Thirty-two functional neuromuscular stimulation ambulation training sessions using a commercially available system (Parastep-1). The hybrid system consists of a microprocessor-controlled stimulator and a modified walking frame with finger-operated switches that permit the user to control the stimulation parameters and activate the stepping. OUTCOME MEASURES Distance walked, time spent standing and walking, pace, circumferential (shoulders, chest, abdomen, waist, hips, upper arm, thigh, and calf) and skinfold (chest, triceps, axilla, subscapular, supraillium, abdomen, and thigh) measurements, body weight, thigh cross-sectional area, and calculated lean tissue. RESULTS Statistically significant changes in distance, time standing and walking, and pace were found. Increases in thigh and calf girth, thigh cross-sectional area, and calculated lean tissue, as well as a decrease in thigh skinfold measure, were all statistically significant. CONCLUSIONS The Parastep 1 system enables persons with thoracic-level spinal cord injuries to stand and ambulate short distances but with a high degree of performance variability across individuals. The factors that influence this variability have not been completely identified.
Collapse
Affiliation(s)
- K J Klose
- The Miami Project to Cure Paralysis, Department of Neurological Surgery, University of Miami School of Medicine, FL 33136, USA
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Jacobs PL, Nash MS, Klose KJ, Guest RS, Needham-Shropshire BM, Green BA. Evaluation of a training program for persons with SCI paraplegia using the Parastep 1 ambulation system: part 2. Effects on physiological responses to peak arm ergometry. Arch Phys Med Rehabil 1997; 78:794-8. [PMID: 9344295 DOI: 10.1016/s0003-9993(97)90189-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To examine the task-nonspecific effects of functional neuromuscular stimulation (FNS)-assisted ambulation training on the physiological responses of persons with paraplegia to upper extremity exercise challenge. DESIGN Before-after trial. SETTING Human spinal cord injury (SCI) applied research laboratory. PARTICIPANTS Twelve men and three women with motor- and sensory-complete thoracic-level SCI (T4-T11), mean age 28.2 +/- 6.8yrs (range, 21.1 to 45.2yrs), mean injury duration 3.7 +/- 3.0yrs (range, 7 to 8.8yrs). INTERVENTION Thirty-two sessions of FNS ambulation training using a commercial six-channel system (Parastep 1). This system is composed of a microprocessor-controlled electrical stimulation unit and a walking frame outfitted with finger switches that allow the user to independently control the system and stimulation parameters. OUTCOME MEASURES Peak and subpeak physiological responses to arm ergometry testing and upper extremity strength measures, obtained before and after the FNS ambulation training. RESULTS Statistically significant increases in peak values for time to fatigue, peak power output, and peak VO2 (all p < .001). Heart rate was significantly lower throughout subpeak levels of arm ergometry after the ambulation training (p < .05). Values of upper extremity strength were not significantly altered after training. CONCLUSIONS FNS ambulation by persons with SCI paraplegia results in task-nonspecific training adaptations. Central cardiovascular adaptations were indicated as the primary source of these beneficial alterations in exercise responses.
Collapse
Affiliation(s)
- P L Jacobs
- The Miami Project to Cure Paralysis and the Department of Neurological Surgery, University of Miami School of Medicine, FL 33136, USA
| | | | | | | | | | | |
Collapse
|
35
|
Jacobs PL, Klose KJ, Guest R, Needham-Shropshire B, Broton JG, Green BA. Relationships of oxygen uptake, heart rate, and ratings of perceived exertion in persons with paraplegia during functional neuromuscular stimulation assisted ambulation. Spinal Cord 1997; 35:292-8. [PMID: 9160453 DOI: 10.1038/sj.sc.3100435] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Previous reports have described significant limitations in the daily use of functional neuromuscular stimulation (FNS) ambulation systems by persons with spinal cord injuries (SCI). The potential application of these devices to provide physiological benefits as an exercise modality has prompted a reconsideration of the technology. However, the acute physiological effects related to the use of FNS systems have not been thoroughly examined. The purpose of this study was to investigate the relationships of oxygen consumption (VO2), heart rate (HR), and ratings of perceived exertion (RPE) during FNS ambulation by persons with SCI paraplegia. Eleven persons with thoracic level paraplegia, aged 21.5 to 38.0 years, participated in an incremental FNS ambulation test. Metabolic measures were collected continuously via open circuit spirometry as the subjects performed a series of ambulation passes of progressively increasing pace. At the end of each ambulation pass, HR and RPE measures were collected. The test was terminated when either the subjects judged the effort to be maximal or when the investigators deemed the effort to be maximal based on HR. A strong linear relationship was documented between the VO2 and HR measures of all subjects throughout subpeak levels of FNS ambulation. RPE did not vary proportionally with VO2 until relatively high levels of exercise intensity were reached. This study indicates that HR, but not RPE, is an appropriate indicator of exercise intensity for persons with SCI paraplegia using a FNS ambulation system.
Collapse
Affiliation(s)
- P L Jacobs
- Miami Project to Cure Paralysis, Florida, USA
| | | | | | | | | | | |
Collapse
|
36
|
Lee TT, Arias JM, Andrus HL, Quencer RM, Falcone SF, Green BA. Progressive posttraumatic myelomalacic myelopathy: treatment with untethering and expansive duraplasty. J Neurosurg 1997; 86:624-8. [PMID: 9120625 DOI: 10.3171/jns.1997.86.4.0624] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Patients with progressive posttraumatic myelomalacic myelopathy (PPMM), or tethered cord syndrome, present with symptoms and signs similar to those observed in case of progressive posttraumatic cystic myelopathy, that is, sensorimotor function deterioration, local and/or radicular pain, increased spasticity, increased autonomic dysreflexia, and sphincter dysfunction. The authors investigated surgical outcomes of untethering combined with expansive duraplasty. Forty patients with PPMM who presented with functional deterioration underwent untethering of the spinal cord and nerve roots with an expansive duraplasty. Meticulous dissections of adhesions on the dorsal and lateral aspects of the spinal cord and nerve roots were performed. Intraoperative ultrasonography was used to detect the presence of a confluent cyst and to assess the success of untethering. After surgery, the patients were treated using a protocol that involved frequent turning for 48 hours and subsequently mobilization. Preoperative magnetic resonance (MR) imaging, with and without administration of a contrast agent, was obtained in all patients, except one patient who underwent immediate and delayed computerized tomography (CT) myelography. The mean follow-up period was 3 years (range 20-57 months) for the 36 patients available for follow-up review. Spinal cord tethering was observed in all patients preoperatively. Trauma was the most common cause of this pathology, accounting for 31 of the 40 cases. Preoperative MR imaging did not demonstrate tumor recurrence in the group of five patients who had undergone an initial operation for tumor excision. The interval between the causative event and the operation was less than 5 years in half of the patients (20 of 40), with the longest interval lasting up to 37 years. Motor function deterioration was the most frequent manifestation; it was present in 31 of 40 patients. Improvements in motor function, autonomic dysreflexia, pain, sphincter dysfunction, and sensory function were found during the most recent follow-up examination in 79%, 75%, 62%, 50%, and 43% of the patients, respectively. Two patients experienced retethering of the spinal cord and one underwent a second operation. Surgical untethering and expansive duraplasty, followed by postoperative position rotation to avoid retethering, provide symptomatic relief for patients with PPMM.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami School of Medicine, Florida, USA
| | | | | | | | | | | |
Collapse
|
37
|
Lee TT, Manzano GR, Green BA. Modified open-door cervical expansive laminoplasty for spondylotic myelopathy: operative technique, outcome, and predictors for gait improvement. J Neurosurg 1997; 86:64-8. [PMID: 8988083 DOI: 10.3171/jns.1997.86.1.0064] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Twenty-five patients underwent an expansive cervical laminoplasty for nontraumatic cervical spondylosis with myelopathy during the period from June 1990 to November 1994, and all had a minimum of 18 months of follow-up review. The open-door laminoplasty procedure presently reported consisted of the same approach evaluated by Hirabayashi in 1977, except that the authors of this report used three rib allografts to anchor the "open door," rather than spinous process sutures or autologous bone grafts. Posterior foraminotomies and decompression were performed in patients with clinical radiculopathy and radiographic evidence of foraminal stenosis. Preoperatively, gait disturbance was present in all patients. All 25 patients (100%) had long-tract signs on presentation. Nondermatomal upper-extremity symptoms (numbness, tingling, weakness, and pain) were quite common in this group of patients. Bowel, bladder, and/or sexual dysfunction was found in 13 (52%) of 25 patients. Preoperative radiographic studies showed a mean midline anteroposterior diameter spinal canal/vertebral body (SC/VB) ratio of 0.623 and a mean compression ratio (sagittal/lateral diameter ratio x 100%) of 37%. This procedure was quite successful in relieving preoperative symptoms and few complications occurred. Gait disturbance was improved in 21 (84%) of 25 patients and hand numbness and tingling were improved in 13 (87%) of 15 patients. Bowel or bladder function improved in 10 (77%) of 13 patients. Radiculopathy, when present, was alleviated in all four patients after the decompressive procedure. The postoperative SC/VB ratio, as measured by plain lateral radiographs and/or computerized tomography scans, was improved to 0.871, a 38% improvement. In a comparison with the preoperative SC/VB ratio using the two-tailed t-test, alpha was less than 0.001. The compression ratio improved to 63% postoperatively, which yielded an alpha of less than 0.005 according to the two-tailed t-test. Only one postoperative complication, an anterior scalene syndrome, was encountered. Various predictors of surgical outcome based on gait improvement were evaluated. Age greater than 60 years at the time of presentation, duration of symptoms more than 18 months prior to surgery, preoperative bowel or bladder dysfunction, and lower-extremity dysfunction were found to be associated with poorer surgical outcome. Even when these conditions were present, gait improvement was noted in at least 70% of the patients.
Collapse
Affiliation(s)
- T T Lee
- Department of Neurological Surgery, University of Miami School of Medicine, Florida, USA
| | | | | |
Collapse
|
38
|
Quencer RM, Nunez D, Green BA. Controversies in imaging acute cervical spine trauma. AJNR Am J Neuroradiol 1997; 18:1866-8. [PMID: 9403443 PMCID: PMC8337364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- R M Quencer
- University of Miami/Jackson Memorial Medical Center, Fla 33136, USA
| | | | | |
Collapse
|
39
|
Abstract
Occlusion of the major components of the spinal venous system is usually associated with spinal arteriovenous malformations or systemic thrombophlebitis. Although spinal venous system dysfunction has been implicated in compressive cord syndromes, myelopathies from decompression sickness, and spinal cord trauma, its pathophysiology remains unclear. To characterize disorders associated with spinal venous occlusion, we developed a model in the rat produced by focally coagulating the dorsal spinal vein transdurally at the T7 and T10 vertebral levels. Following such occlusion, venous stasis, sludging and perivascular hemorrhages in the small venous branches were observed. By 1 week postocclusion, animals developed hindlimb paralysis from which they partially recovered over time. Histologic examination in the acute phase disclosed tissue necrosis, edema, and hemorrhages predominantly in the dorsal aspect of the spinal cord. This was gradually replaced by an intense macrophagic infiltration and the partial formation of a cystic cavity by 1 month. These findings indicate that dorsal spinal vein occlusion in the rat causes significant neurologic and pathologic alterations. We conclude that this procedure produces a relevant animal model for the study of the pathophysiology of spinal venous occlusion, and it allows the characterization of its effects on spinal cord blood flow, the blood-spinal cord barrier, and the development of edema independent of cord compression. Our findings in this model provide an insight into one of the mechanisms of injury extension in spinal cord trauma and other disorders associated with spinal venous dysfunction.
Collapse
Affiliation(s)
- A Martinez-Arizala
- Miami Project to Cure Paralysis, University of Miami, School of Medicine, Florida, USA
| | | | | | | | | |
Collapse
|
40
|
Nash MS, Bilsker MS, Kearney HM, Ramirez JN, Applegate B, Green BA. Effects of electrically-stimulated exercise and passive motion on echocardiographically-derived wall motion and cardiodynamic function in tetraplegic persons. Paraplegia 1995; 33:80-9. [PMID: 7753573 DOI: 10.1038/sc.1995.20] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The purposes of the study were (1) to characterize left ventricular wall motion, and the cardiodynamic and metabolic responses during electrical stimulation cycle ergometry (ESCE) exercise in tetraplegic people; (2) to test whether these responses linger into the post-exercise recovery period; and (3) to test whether they differ from those imposed by lower extremity continuous passive motion (CPM). Subjects were six tetraplegic males aged 25.8 +/- 3.1 (mean +/- SD) years with spinal cord injuries of 6.7 +/- 3.5 years' duration at the C5 and C6 levels (Frankel classifications A and B). On randomized non-consecutive days, subjects underwent either 30 min of steady-state exercise using transcutaneous electrically-stimulated contractions of bilateral quadriceps, hamstring, and gluteus muscle groups, or 30 min of continuous passive motion at 50 rpm. Data were taken at rest, min 15 and 30 of treatment, and min 5, 15, and 30 post-treatment. Stroke volume (SV) was measured echocardiographically as the product of the left ventricular outflow tract area and the integrated area under the left ventricular outflow tract flow-velocity curve acquired by doppler ultrasound. This value was multiplied by heart rate (HR) to determine the cardiac output (CO). Oxygen consumption (VO2) was monitored spirometrically, with arteriovenous oxygen difference (a-vO2DIFF) computed algebraically. Data were analyzed using repeated measures within-subjects design anaysis of variance, with significance accepted at the 0.05 level. Results showed five subjects had small hyperkinetic ventricles at rest that became more dynamic during ESCE than CPM. Though no systolic dysfunction was noted, all but one subject exhibited some degree of septal hypokinesis at rest and during exercise, possibly indicative of left ventricular noncompliance. Significant effects of condition (ESCE vs CPM), trial (measurement time point), and their interaction, were observed for CO (P < 0.05, 0.01, and 0.0001, respectively), HR (P < 0.0001, 0.05 and 0.005, respectively), and VO2 (P < 0.001, 0.05 and 0.005, respectively). A significant trial and condition by trial interaction was found for a-vO2DIFF (P < 0.05 and 0.0001, respectively). No effects for condition, trial or their interaction were found for SV or BPDIAS. Electrical stimulation cycle ergometry-treated subjects achieved peak VO2 of 712 +/- 300 ml min-1, 2.63 times baseline, with 56% elevation of a-vO2DIFF. Cardiac output increased from 3.5 +/- 1.51 min-1 to 6.0 +/- 2.11 min-1, an elevation solely attributable to a 57% increase in HR. Thus, both CO and a-vO2DIFF accounted for elevated VO2 during ESCE.(ABSTRACT TRUNCATED AT 400 WORDS)
Collapse
Affiliation(s)
- M S Nash
- Department of Orthopaedics and Rehabilitation, University of Miami School of Medicine, Coral Gables, Florida 33146, USA
| | | | | | | | | | | |
Collapse
|
41
|
Abstract
Reducing the number of residency positions in U.S. teaching hospitals poses special problems for New York City-area hospitals, which rely heavily on residents to deliver patient care services. This study analyzes the costs of replacing residents with midlevel practitioners under proposals considered in 1994 by Congress to limit the number of first-year training positions and alter the configuration of primary care physicians and specialists produced. The study found that, depending on the replacement strategy used, the proposals could require New York City-area hospitals to hire thousands of midlevel practitioners and other staff, costing a minimum of $242 million annually, to cover patient care services.
Collapse
Affiliation(s)
- B A Green
- Greater New York Hospital Association (GNYHA), New York City, USA
| | | |
Collapse
|
42
|
Bowen BC, Fraser K, Kochan JP, Pattany PM, Green BA, Quencer RM. Spinal dural arteriovenous fistulas: evaluation with MR angiography. AJNR Am J Neuroradiol 1995; 16:2029-43. [PMID: 8585491 PMCID: PMC8337234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
PURPOSE To show that postgadolinium three-dimensional time-of-flight MR angiography shows abnormal intradural vessels associated with spinal dural arteriovenous fistula better than routine MR imaging and provides screening information useful for subsequent diagnostic conventional angiography and/or posttreatment evaluation. METHODS Precontrast and postcontrast MR imaging and MR angiograms, as well as subsequent digital subtraction angiograms, were obtained for eight patients with dural arteriovenous fistulas, diagnosed with digital subtraction angiography and verified with surgery. In four patients, MR studies also were obtained after surgery. RESULTS All patients had cord hyperintensity of T2-weighted images and postgadolinium enhancement on T1-weighted images. Five had vessellike signal abnormalities in the subarachnoid space on MR. Abnormal intradural vessels were detected in all eight patients with MR angiography. Comparison with digital subtraction angiography revealed these vessels to be primarily enlarged veins of the coronal venous plexus on the cord surface. In six patients, the medullary vein draining the fistula was demonstrated, indicating the level of the fistula, later identified by digital subtraction angiography. After surgical obliteration of the fistula, the draining medullary vein and most or all of the abnormal coronal veins were no longer demonstrated, with decrease or resolution of cord hyperintensity on T2-weighted images. CONCLUSION Postgadolinium, spinal MR angiography in cases of suspected dural arteriovenous fistula provides information about intradural veins that supplements the diagnostic value of the MR imaging results, facilitates the subsequent digital subtraction angiography study, and, in treated cases, reflects the success of surgery and/or embolization.
Collapse
Affiliation(s)
- B C Bowen
- Department of Radiology, University of Miami School of Medicine, USA
| | | | | | | | | | | |
Collapse
|
43
|
Calancie B, Needham-Shropshire B, Jacobs P, Willer K, Zych G, Green BA. Involuntary stepping after chronic spinal cord injury. Evidence for a central rhythm generator for locomotion in man. Brain 1994; 117 ( Pt 5):1143-59. [PMID: 7953595 DOI: 10.1093/brain/117.5.1143] [Citation(s) in RCA: 266] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We investigated a pattern of involuntary lower extremity stepping-like movements which recently appeared in a subject with a 17-year history of neurologically incomplete injury to the cervical spinal cord. The movements were rhythmic, alternating and forceful, involved all muscles of the lower extremities and could be reliably evoked by lying the subject down (supine) and extending his hips. Once in this position, the movements continued spontaneously, in the absence of external sensory perturbations, with a step-cycle duration of approximately 3.5 s (0.3 Hz). This rate could be either increased or temporarily halted by specific sensory inputs. Anaesthetizing the subject's right hip joint, in which we found evidence of pathology, led to a marked attenuation of the stepping movements for a period of approximately 15 min. We believe that a combination of (i) preserved but limited supraspinal tonic facilitation, and (ii) abnormal, perhaps noxious afferent inflow from the subject's right hip to the spinal cord may underlie the appearance of this highly unusual and involuntary movement pattern. The striking similarity between the movement and EMG patterns in this subject and those described in many reports using the surgically reduced cat model suggests that we were witnessing the first well-defined example of a central rhythm generator for stepping in the adult human.
Collapse
Affiliation(s)
- B Calancie
- Miami Project to Cure Paralysis, FL 33136
| | | | | | | | | | | |
Collapse
|
44
|
Nash MS, Tehranzadeh J, Green BA, Rountree MT, Shea JD. Magnetic resonance imaging of osteonecrosis and osteoarthrosis in exercising quadriplegics and paraplegics. Am J Phys Med Rehabil 1994; 73:184-92. [PMID: 8198775 DOI: 10.1097/00002060-199406000-00007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Degenerative bone and joint diseases that commonly accompany spinal cord injury (SCI) may be exacerbated by physical activity of the lower extremities. To determine if orthopaedic stress imposed by electrically stimulated cycling exercise is associated with osteonecrosis or osteoarthrosis in persons with chronic SCI, ten quadriplegics and paraplegics who had each undergone electrical stimulation cycle ergometry exercise two or three times weekly for longer than 1.5 years underwent magnetic resonance examinations of the femoral heads and the dominant knee. Three of the ten subjects had no evidence of meniscal or bone marrow pathologies, osteochondritis dessicans, avascular necrosis, joint effusion or accumulation or soft tissue tears. The magnetic resonance scans of six subjects were noted to have very mild effusion, slight meniscal degeneration and minimal chondromalacia patellae. Consistent patterns of bone or joint pathology were not discernible among these scans, and the positive findings did not represent threatening clinical states. The scans of one subject showed heterogenous regions of bone infarct characteristic of osteochondritis and avascular necrosis, observations that were atypical of all other subjects. No injuries consistent with the biomechanics of cycling exercise were observed in any subject. Despite the high sensitivity of magnetic resonance imaging in detecting bone and joint deterioration, significant bone and joint findings represented only 14 of 150 observations, less than previously reported in sedentary subjects with SCI. This study suggests that electrical stimulation cycle ergometry does not foster bone or joint deterioration in individuals with chronic SCI.
Collapse
Affiliation(s)
- M S Nash
- Department of Orthopaedics and Rehabilitation, University of Miami School of Medicine, Florida
| | | | | | | | | |
Collapse
|
45
|
Falcone S, Quencer RM, Green BA, Patchen SJ, Post MJ. Progressive posttraumatic myelomalacic myelopathy: imaging and clinical features. AJNR Am J Neuroradiol 1994; 15:747-54. [PMID: 8010278 PMCID: PMC8334203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
PURPOSE To describe the imaging features, surgical management, and clinical outcome of progressive posttraumatic myelomalacic myelopathy (PPMM), a relatively unrecognized but important cause of progressive myelopathy in patients with previous spinal cord injuries. METHODS The clinical records, imaging studies, and postoperative outcome of 10 patients with PPMM were reviewed. Fifteen preoperative and five postoperative MRs were analyzed for intramedullary signal abnormalities, the nature of these signal abnormalities, and cord tethering. All patients had intraoperative sonography. RESULTS Neurologic signs and symptoms found in our patients included 1) progressive loss of motor function (6/10), 2) sensory level changes (4/10), 3) increased spasticity (4/10), 4) autonomic dysreflexia (4/10), 5) loss of bowel or bladder control (4/10), and 6) local and/or radicular pain (4/10). Preoperative MR in nine patients revealed intramedullary T1/T2 lengthening (9/9), extramedullary tethering/adhesions (9/9), ill-defined lesional borders (6/9), cord expansion (5/9), and increased signal intensity of the lesion on T1-weighted images compared with CSF (7/9). Proton density images in five patients demonstrated a relative increase in signal intensity over CSF. In all five postoperative MRs, there was evidence of untethering of the spinal cord and a decrease in cord size in two patients. Intraoperative sonography revealed cord tethering and abnormal cord echotexture in all cases. Postoperative clinical evaluation revealed neurologic improvement in nine patients. CONCLUSIONS PPMM may clinically and radiographically mimic progressive posttraumatic cystic myelopathy (PPCM). MR provides clues to the diagnosis of myelomalacia preoperatively. Intraoperative sonography confirms the absence of a confluent cyst. These points are crucial in the surgical procedures in PPMM vs PPCM. In PPMM, lysis of intradural adhesions results in an improvement in symptoms in a manner similar to the shunting of PPCM.
Collapse
Affiliation(s)
- S Falcone
- Department of Radiology, University of Miami/Jackson Memorial Medical Center
| | | | | | | | | |
Collapse
|
46
|
Abstract
Transthoracic discectomy and fusion were performed on 19 patients for a central or central-lateral herniated thoracic disc. At initial visit, 14 patients had evidence of myelopathy, 5 had bowel or bladder dysfunction, and 13 had pain. Previous laminectomy in three patients compromised the result of later anterior decompression. Coexistent multiple sclerosis was diagnosed in two patients, who had an atypical postoperative course. The overall results of transthoracic discectomy and fusion in patients without prior laminectomy or coexistent multiple sclerosis were excellent in six, good in six, fair in one, and poor in one, demonstrating that it is a safe and effective procedure.
Collapse
Affiliation(s)
- B L Currier
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota
| | | | | |
Collapse
|
47
|
Affiliation(s)
- B A Green
- Department of Bacteriology Research, Lederle-Praxis Biologicals, Inc., West Henrietta, New York 14586
| | | | | |
Collapse
|
48
|
Singer C, Green BA, Bruce JH, Bowen BC, Weiner WJ. Late presentation of congenital muscular torticollis: use of MR imaging and CT scan in diagnosis. Mov Disord 1994; 9:100-3. [PMID: 8139587 DOI: 10.1002/mds.870090117] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A 17-year old boy presented with a 10-year history of progressive head tilt to the right. Bilateral posterolateral cervical pain was mild and he was fully functional. The right sternocleidomastoid (SCM) muscle was prominent without rotation of the head to the left. The SCM had a cord-like consistency on palpation. Magnetic resonance (MR) and computed tomography (CT) scan imaging of the neck musculature suggested fibrous tissue within the substance of the muscle. This was histopathologically confirmed when the right SCM was surgically explored and resected. Congenital muscular torticollis is usually seen in newborns, infants, and children but may also present in adolescence and young adulthood. It should be included in the differential diagnosis of cervical dystonia as one of the nondystonic causes of abnormal head posture. Combined use of MR and CT scan of neck muscles may be of help in the diagnosis.
Collapse
Affiliation(s)
- C Singer
- Department of Neurology, University of Miami School of Medicine, Florida
| | | | | | | | | |
Collapse
|
49
|
Wester DJ, Falcone S, Green BA, Camp A, Quencer RM. Paraganglioma of the filum: MR appearance. J Comput Assist Tomogr 1993; 17:967-9. [PMID: 8227586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Paragangliomas are benign tumors that are thought to arise from the neuroectodermally derived paraganglionic cells of the sympathetic nervous system. We report the imaging findings of an unusual case of paraganglioma of the filum terminale.
Collapse
Affiliation(s)
- D J Wester
- University of Miami School of Medicine/Jackson Memorial Medical Center, FL 33136
| | | | | | | | | |
Collapse
|
50
|
Affiliation(s)
- J J Hoski
- University of Miami School of Medicine, Florida 33101
| | | | | |
Collapse
|