Management of recurrent giant hemangiopericytoma: illustrative cases

BACKGROUND

Hemangiopericytoma (HPC) is a rare malignancy accounting for 0.4% of intracranial tumors. HPCs are characterized by local aggressiveness, high rates of recurrence, and a tendency to metastasize to extracranial sites. These features make management of HPCs challenging, often requiring a combination of radical resection and radiation. Given their rarity, optimal treatment algorithms remain undefined.

OBSERVATIONS

The authors report a series of four patients who underwent resection of intracranial HPC. Mean age at presentation was 49.3 years. Three patients had reoperation for progression of residual tumor, and one patient was surgically retreated for recurrence. One patient received adjuvant radiotherapy following initial resection, and three patients received adjuvant radiotherapy following resection of recurrent or residual disease. There was one death in the series. Average progression-free survival and overall survival following the index procedure were 32.8 and 82 months, respectively. Progression occurred locally in all patients, with metastatic recurrence in one patient.

LESSONS

The current gold-standard treatment for intracranial HPC consists of gross-total resection followed by radiation therapy. This approach allows satisfactory local control; however, given the tendency for these tumors to recur either locally or distally within or outside of the central nervous system, there is a need for salvage therapies to improve long-term outcomes for patients.

Microvascular Decompression for Trigeminal Neuralgia Caused by Vascular Compression on the Trigeminal Sensory Nucleus and Descending Trigeminal Tract

BACKGROUND

Trigeminal neuralgia (TN) is characterized by paroxysmal episodes of severe shocklike orofacial pain typically resulting from arterial compression on the trigeminal root entry zone. However, neurovascular conflict in more proximal parts of the trigeminal pathway within the pons is extremely rare.

METHODS

The authors present a case of microvascular decompression for TN caused by dual arterial compression on the dorsolateral pons, along with a brief literature review.

RESULTS

Our patient was a 74-year-old man with episodic left-sided facial stabbing pain. Brain magnetic resonance imaging revealed a dual arterial compression on dorsolateral pons, the known site of the trigeminal sensory nucleus and descending trigeminal tract. Microvascular decompression was performed via a retrosigmoid approach. Complete pain relief and partial improvement of the facial hypesthesia were achieved immediately after surgery and the Barrow Neurological Institute (BNI) pain intensity score improved from V to I, and the BNI hypesthesia score decreased from III to II within a month following surgery. The literature review identified 1 case of TN secondary to an arteriovenous malformation in root entry zone with lateral pontine extension. One month following partial coagulation of the draining vein, the patient was reportedly able to reduce medication dosage by half to achieve an improvement of BNI pain intensity score from V to IIIa.

CONCLUSIONS

Neurovascular compression in the trigeminal tract and nucleus is a rare but potential cause of TN. A thorough investigation of the trigeminal pathway should be considered during preoperative evaluation and intraoperative inspection, particularly if no clear offending vessel is identified.

Intradural Pituitary Hemitransposition: Technical Note and Case Series Illustration

BACKGROUND AND OBJECTIVES

Lesions located in the retrosellar region, interpeduncular cistern, and petroclival region are among the most difficult to access in neurosurgery. Transcranial approaches are useful; however, the large distance between the surgeon and the lesion as well as the presence of major neurovascular structures surrounding the lesion may limit surgical exposure. A midline transsphenoidal route avoids transgression of the neurovascular plane and provides direct access to the interpeduncular cistern. To safely access the interpeduncular fossa, it requires mobilization of the pituitary gland. The pituitary hemitransposition technique permits mobilization of the gland, while preserving its venous drainage and arterial supply to the gland on one of its sides, preserving gland function. The authors aim to describe the intradural pituitary hemitransposition technique and to demonstrate its safe application for resection of skull base tumors in the retrosellar space.

METHODS

The authors describe the surgical technique and illustrate its application in 5 cases of different types of skull base tumors, including a video demonstrating all the steps to perform this approach. In addition, the authors discuss the advantages and limitations of this technique compared with other approaches to the retrosellar space.

RESULTS

The intradural pituitary hemitransposition technique was used to safely resect a chondrosarcoma, chordoma, craniopharyngioma, teratoma, and meningioma involving the parasellar and retrosellar spaces, while minimizing endocrine morbidity. We had one patient with mild, albeit permanent hyperprolactinemia and hypothyroidism after surgery. No other patients had permanent dysfunction related to surgery.

CONCLUSION

The endonasal endoscopic intradural pituitary hemitransposition approach is an effective technique for resection of lesions located within the retrosellar and petroclival regions, allowing adequate exposure while potentially optimizing the preservation of the pituitary function.

Real-time ultrasound guidance in the endoscopic endonasal resection of a retro-odontoid pannus: Technical note and case illustration

Background and Objectives

Odontoidectomy is a surgical procedure indicated in the setting of various pathologies, with the main goal of decompressing the ventral brain stem and spinal cord as a result of irreducible compression at the craniovertebral junction. The endoscopic endonasal approach has been increasingly used as an alternative to the transoral approach as it provides a straightforward, panoramic, and direct approach to the odontoid process. In addition, intraoperative ultrasound (US) guidance is a technique that can optimize safety and surgical outcomes in this context. It is used as an adjunct to neuronavigation and provides intraoperative confirmation of decompression of craniovertebral junction structures in real time. The authors aim to present the use and safe application of real-time intraoperative US guidance during endonasal endoscopic resection of a retro-odontoid pannus.

Methods

A retrospective chart review of a single case was performed and presented herein as a case report and narrated operative video.

Results

A minimally invasive US transducer was used intraoperatively to guide the resection of a retro-odontoid pannus and confirm spinal cord decompression in real time. Postoperative examination of the patient revealed immediate neurological improvement.

Conclusions

Intraoperative ultrasonography is a well described and useful modality in neurosurgery. However, the use of intraoperative US guidance during endonasal endoscopic approaches to the craniovertebral junction has not been previously described. As demonstrated in this technical note, the authors show that this imaging modality can be added to the ever-evolving armamentarium of neurosurgeons to safely guide the decompression of neural structures within the craniocervical junction with good surgical outcomes.

Identification of potential blood biomarkers associated with suicide in major depressive disorder

Suicides have increased to over 48,000 deaths yearly in the United States. Major depressive disorder (MDD) is the most common diagnosis among suicides, and identifying those at the highest risk for suicide is a pressing challenge. The objective of this study is to identify changes in gene expression associated with suicide in brain and blood for the development of biomarkers for suicide. Blood and brain were available for 45 subjects (53 blood samples and 69 dorsolateral prefrontal cortex (DLPFC) samples in total). Samples were collected from MDD patients who died by suicide (MDD-S), MDDs who died by other means (MDD-NS) and non-psychiatric controls. We analyzed gene expression using RNA and the NanoString platform. In blood, we identified 14 genes which significantly differentiated MDD-S versus MDD-NS. The top six genes differentially expressed in blood were: PER3, MTPAP, SLC25A26, CD19, SOX9, and GAR1. Additionally, four genes showed significant changes in brain and blood between MDD-S and MDD-NS; SOX9 was decreased and PER3 was increased in MDD-S in both tissues, while CD19 and TERF1 were increased in blood but decreased in DLPFC. To our knowledge, this is the first study to analyze matched blood and brain samples in a well-defined population of MDDs demonstrating significant differences in gene expression associated with completed suicide. Our results strongly suggest that blood gene expression is highly informative to understand molecular changes in suicide. Developing a suicide biomarker signature in blood could help health care professionals to identify subjects at high risk for suicide.

Splice-Break: exploiting an RNA-seq splice junction algorithm to discover mitochondrial DNA deletion breakpoints and analyses of psychiatric disorders

Deletions in the 16.6 kb mitochondrial genome have been implicated in numerous disorders that often display muscular and/or neurological symptoms due to the high-energy demands of these tissues. We describe a catalogue of 4489 putative mitochondrial DNA (mtDNA) deletions, including their frequency and relative read rate, using a combinatorial approach of mitochondria-targeted PCR, next-generation sequencing, bioinformatics, post-hoc filtering, annotation, and validation steps. Our bioinformatics pipeline uses MapSplice, an RNA-seq splice junction detection algorithm, to detect and quantify mtDNA deletion breakpoints rather than mRNA splices. Analyses of 93 samples from postmortem brain and blood found (i) the 4977 bp ‘common deletion’ was neither the most frequent deletion nor the most abundant; (ii) brain contained significantly more deletions than blood; (iii) many high frequency deletions were previously reported in MitoBreak, suggesting they are present at low levels in metabolically active tissues and are not exclusive to individuals with diagnosed mitochondrial pathologies; (iv) many individual deletions (and cumulative metrics) had significant and positive correlations with age and (v) the highest deletion burdens were observed in major depressive disorder brain, at levels greater than Kearns–Sayre Syndrome muscle. Collectively, these data suggest the Splice-Break pipeline can detect and quantify mtDNA deletions at a high level of resolution.

Long term compliance with California's Smoke-Free Workplace Law among bars and restaurants in Los Angeles County

OBJECTIVE

To assess long term compliance with the California Smoke-Free Workplace Law in Los Angeles County freestanding bars and bar/restaurants.

DESIGN

Population based annual site inspection survey of a random sample of Los Angeles County freestanding bars and bar/restaurants was conducted from 1998 to 2002.

MAIN OUTCOME MEASURES

The primary outcomes of interest were patron and employee smoking. The secondary outcomes of interest were the presence of ashtrays and designated outdoor smoking areas.

RESULTS

Significant increases in patron non-smoking compliance were found for freestanding bars (45.7% to 75.8%, p < 0.0001) and bar/restaurants (92.2% to 98.5%, p < 0.0001) between 1998 and 2002. Increases in employee non-smoking compliance were found for freestanding bars (86.2% to 94.7%, p < 0.0003) and bar/restaurants (96.5% to 99.2%, p < 0.005).

CONCLUSIONS

This study provides clear evidence that the California Smoke-Free Workplace Law has been effective at reducing patron and employee smoking in Los Angeles County bars and restaurants. Recommendations include educational campaigns targeted to freestanding bar owners and staff to counter perceptions of lost revenue, more rigorous enforcement, and more severe penalties for repeat violators such as alcohol licence revocation. Policymakers can enact smoke-free restaurant and bar policies to protect employees and patrons from secondhand smoke, confident that these laws can be successfully implemented.

Evaluation of ergonomic dental stools through clinical simulation

Work-related musculoskeletal pain occurs commonly within the dental community. Three stool designs were utilized in this study: a standard dental stool, a stool with dual arm supports, and a stool with dual arm supports and chest support. Electromyographic data from four muscle groups were collected on 13 clinicians during a simulated crown preparation procedure. Clinical simulation suggests that a potential musculoskeletal benefit to the clinician exists through utilization of dental stool designs which incorporate static arm supports.

A probability-based approach for predicting HIV infection in a low prevalent population of injection drug users

This article proposes a method for estimating HIV risk in low-HIV-prevalent populations. Allard's risk probability model was used to compute individual risk scores. Based on a sample of 3854 injection drug users (IDUs) who were confidentially tested for HIV at five methadone treatment clinics in Los Angeles County, the following self-reported risk behaviors were used to derive an individual IDU risk score: (i) frequency of injection, (ii) frequency of using uncleaned needles, (iii) number of people sharing a needle, (iv) frequency of needle sharing, and (v) type of needle sharing practice. The overall HIV prevalence for the IDU sample was 2%. The risk score was strongly associated with HIV seropositivity (chi-square = 16.1, p < 0.0001), but only one of the individual IDU risk behaviors (needle cleaning) was significantly associated with HIV seropositivity (chi-square = 10.9, P < 0.001). In addition, the risk score was strongly associated with HIV serostatus for both males and females. For females, however, none of the individual IDU risk behaviors were associated with HIV serostatus. Our findings indicate that when predicting HIV infection in a low-prevalence population, the probability-based risk score makes a statistically significant contribution over individual IDU risk behaviors.

Occupational risk of acquiring HIV infection through needlestick injuries

Accidental needlestick exposures occur frequently among hospital personnel and account for most incidents of percutaneous injuries. Even if universal precautions were followed routinely, it is unlikely that multiple needlestick exposures could be avoided completely. Despite the likelihood of persons incurring multiple needlestick exposures, relatively little information is available on the cumulative risk of human immunodeficiency virus (HIV) infection for health care workers attending unrecognized HIV-infected patients. A quantitative method to estimate annual cumulative risk from multiple exposures is offered, and the risk of HIV infection is estimated by use of a probability model for health care workers in both hospital and emergency department settings.

The effects of three modalities on delayed onset muscle soreness

Delayed onset muscle soreness is a common problem that can interfere with rehabilitation as well as activities of daily living. The purpose of this study was to test the impact of therapeutic massage, upper body ergometry, or microcurrent electrical stimulation on muscle soreness and force deficits evident following a high-intensity eccentric exercise bout. Forty untrained, volunteer female subjects were randomly assigned to one of three treatment groups or to a control group. Exercise consisted of high-intensity eccentric contractions of the elbow flexors. Resistance was reduced as subjects fatigued, until they reached exhaustion. Soreness rating was determined using a visual analog scale. Force deficits were determined by measures of maximal voluntary isometric contraction at 90 degrees of elbow flexion and peak torque for elbow flexion at 60 degrees/sec on a Cybex II isokinetic dynamometer. Maximal voluntary isometric contraction and peak torque were determined at the 0 hour (before exercise) and again at 24 and 48 hours postexercise. Treatments were applied immediately following exercise and again at 24 hours after exercise. The control group subjects rested following their exercise bout. Statistical analysis showed significant increases in soreness rating and significant decreases in force generated when the 0 hour was compared with 24- and 48-hour measures. Further analysis indicated no statistically significant differences between massage, microcurrent electrical stimulation, upper body ergometry, and control groups.

Effect of caffeine on maximal strength and power in élite male athletes

Computerized testing of 20 élite male athletes was performed to determine the effect of 7 mg kg-1 caffeine on strength and power of the knee extensors and flexors. Subjects received counterbalanced administrations of either caffeine or a placebo on two separate occasions. Peak torque (T) was measured for knee extension (ET) and flexion (FT) at angular velocities of 30 degrees, 150 degrees and 300 degrees s-1. Additionally, performance for the first 125 ms (TAE) and power (W) were recorded during 300 degrees s-1. Testing sessions were held 1 week apart, at which time the placebo/caffeine administration was reversed. A 2 x 2 repeated measures analysis of variance supplemented with a Neuman-Keuls post hoc test showed the following--significant caffeine-related increases (P < 0.05) for ET at 30 degrees s-1, ET at 300 degrees s-1, and ETAE, and EW at 300 degrees s-1. Dependent t-tests performed for pre- to post-test means showed significant changes for the caffeine group in ET at 30 degrees s-1, FT at 30 degrees s-1, FT at 150 degrees s-1, ET at 300 degrees s-1, FT at 300 degrees s-1, E and FTAE, and EW at 300 degrees s-1. No significant effects were found for the placebo trial in any variable. It was concluded that caffeine can favourably affect some strength parameters in highly resistance-trained males. However, differences in subject fibre type, motivation and caffeine sensitivity need to be elucidated.

Relative effectiveness of comprehensive community programming for drug abuse prevention with high-risk and low-risk adolescents

This article reviews major risk factors for cigarette smoking, alcohol, and other drug abuse and promising community-based approaches to primary prevention. In a longitudinal experimental study, 8 representative Kansas City communities were assigned randomly to program (school, parent, mass media, and community organization) and control (mass media and community organization only) conditions. Programs were delivered at either 6th or 7th grade, and panels were followed through Grade 9 or 10. The primary findings were (a) significant reductions at 3 years in tobacco and marijuana use and (b) equivalent reductions for youth at different levels of risk. This study provides evidence that a comprehensive community program-based approach can prevent the onset of substance abuse and that the benefits are experienced equally by youth at high and low risk.

Histidine, histamine, and the neuroregulation of food intake: a review and hypothesis

Feeding, a behavior regulated by the central nervous system (CNS), includes the acquisition of specific essential nutrients and the maintenance of energy balance. Modulation of feeding behavior is a normal part of survival, but certain pathological conditions interrupt or modify regulatory aspects of feeding, thereby leading to inappropriate intake. This review examines aspects of metabolism associated with the anorexia seen in animals suffering from protein-energy malnutrition (PEM). The main focus is the indispensable amino acid histidine (His), the biosynthetic precursor of the neurotransmitter histamine (HA). In kwashiorkor-like PEM, His is elevated in plasma and brain, whereas all other indispensable amino acids are decreased. The elevation of His in the brain is to concentrations five times normal. Because the rate of HA synthesis in the brain is a function of the His concentration, His elevation raises the possibility of a profound direct effect of CNS function. In children, PEM consistently produces the symptoms of depressed food intake, edema, growth failure, and psychomotor changes. One known central effect of HA is the stimulation of ACTH and corticosteroid release. Based on these observations, the hypothesis being examined is as follows: one component of the pathophysiological neuroregulation of food intake involved the His-induced variation of HA concentration in the hypothalamus and the subsequently altered neurochemical activity at the corticotropin-releasing factor (CRF) neurons o the paraventricular nucleus (PVN).

Relative effectiveness of comprehensive community programming for drug abuse prevention with high-risk and low-risk adolescents

This article reviews major risk factors for cigarette smoking, alcohol, and other drug abuse and promising community-based approaches to primary prevention. In a longitudinal experimental study, 8 representative Kansas City communities were assigned randomly to program (school, parent, mass media, and community organization) and control (mass media and community organization only) conditions. Programs were delivered at either 6th or 7th grade, and panels were followed through Grade 9 or 10. The primary findings were (a) significant reductions at 3 years in tobacco and marijuana use and (b) equivalent reductions for youth at different levels of risk. This study provides evidence that a comprehensive community program-based approach can prevent the onset of substance abuse and that the benefits are experienced equally by youth at high and low risk.

Project SMART parent program: preliminary results of a chronic disease risk reduction trail

Project SMART Parent Program is a school-based healthy lifestyle promotion program designed to reduce chronic disease risk in adults and to provide a health-conscious home environment for children through the adoption of healthy lifestyle by their parents. Parents in the high involvement condition received comprehensive health status appraisals, and a program designed to reduce dietary fat intake, and increase aerobic activity levels. Parents in the low involvement condition received only the comprehensive health status appraisals. ANCOVA, using treatment condition as the independent variable and change scores as the dependent variables, were used to assess program outcomes. At the first posttest measure, the intervention group compared to the control group had a significantly greater decrease in blood cholesterol, a greater gain in aerobic fitness, a greater weight loss, and a greater decrease in body fat. At the second posttest measure, the intervention group had significantly greater gain in aerobic fitness, a greater decrease in body fat, a greater decrease in systolic blood pressure, and a marginally significant decrease in weight. Preliminary results provide strong support for the effectiveness of the Parent Program in reducing chronic disease risks.

Evidence for two paths of alcohol use onset in adolescents

Research is needed to identify risk factors specifically associated with the development of substance abuse. The current study explored the possibility that adolescents classified as having a problem behavior prone orientation (Type II) are predisposed to more rapid alcohol use onset compared to more normally socialized (Type I) adolescents. It was hypothesized that both types of adolescents would increase their alcohol use over time, but that problem behavior prone adolescents would increase their rates of alcohol consumption more rapidly than would normally socialized adolescents. Using ANCOVA (with baseline alcohol use as a covariate) and t tests (examining only nondrinkers at baseline), the hypotheses were strongly supported. Both Type I and Type II adolescents significantly increased their alcohol use over a one-year period. Type II adolescents, in comparison to Type I adolescents, had significantly higher alcohol use. The greater alcohol use among Type II adolescents was attributed to their problem behavior prone orientation. The findings suggest the existence of two different developmental pathways of alcohol use onset, one initiated by normally socialized adolescents and the other by adolescents with a problem behavior prone orientation. Future alcohol abuse prevention programs may benefit from tailored intervention strategies which take into account population specific risk factors.