Systematic evaluation of imaging techniques and baseline characteristics in patients with suspected vasculitis

Purpose

To assess the diagnostic value of different imaging modalities in distinguishing systemic vasculitis from other internal and immunological diseases.

Methods

This retrospective study included 134 patients with suspected vasculitis who underwent ultrasound, magnetic resonance imaging (MRI), or ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) between 01/2010 and 01/2019, finally consisting of 70 individuals with vasculitis. The main study parameter was the confirmation of the diagnosis using one of the three different imaging modalities, with the adjudicated clinical and histopathological diagnosis as the gold standard. A secondary parameter was the morphological appearance of the vessel affected by vasculitis.

Results

Patients with systemic vasculitis had myriad clinical manifestations with joint pain as the most common symptom. We found significant correlations between different imaging findings suggestive of vasculitis and the final adjudicated clinical diagnosis. In this context, on MRI, vessel wall thickening, edema, and diameter differed significantly between vasculitis and non-vasculitis groups (p < 0.05). Ultrasound revealed different findings that may serve as red flags in identifying patients with vasculitis, such as vascular occlusion or halo sign (p = 0.02 vs. non-vasculitis group). Interestingly, comparing maximal standardized uptake values from PET/CT examinations with vessel wall thickening or vessel diameter did not result in significant differences (p > 0.05).

Conclusions

We observed significant correlations between different imaging findings suggestive of vasculitis on ultrasound or MRI and the final adjudicated diagnosis. While ultrasound and MRI were considered suitable imaging methods for detecting and discriminating typical vascular changes, ¹⁸F-FDG PET/CT requires careful timing and patient selection given its moderate diagnostic accuracy.

Comprehensive comparison of three different workstations for accurate planning of endovascular stent implantation in patients with thoracic aortic aneurysms

Purpose

To assess the diagnostic precision of three different workstations for measuring thoracic aortic aneurysms (TAAs) in vivo and ex vivo using either pre-interventional computed tomography angiography scans (CTA) or a specifically designed phantom model.

Methods

This retrospective study included 23 patients with confirmed TAA on routinely performed CTAs. In addition to phantom tube diameters, one experienced blinded radiologist evaluated the dimensions of TAAs on three different workstations in two separate rounds. Precision was assessed by calculating measurement errors. In addition, correlation analysis was performed using Pearson correlation.

Results

Measurements acquired at the Siemens workstation deviated by 3.54% (range, 2.78–4.03%; p = 0.14) from the true size, those at General Electric by 4.05% (range, 1.46–7.09%; p < 0.0001), and at TeraRecon by 4.86% (range, 3.22–6.45%; p < 0.0001). Accordingly, Siemens provided the most precise workstation at simultaneously most fluctuating values (scattering of 4.46%). TeraRecon had the smallest fluctuation (scattering of 2.83%), but the largest deviation from the true size of the phantom. The workstation from General Electric showed a scattering of 2.94%. The highest overall correlation between the 1st and 2nd rounds was observed with measurements from Siemens (r = 0.898), followed by TeraRecon (r = 0.799), and General Electric (r = 0.703). Repetition of measurements reduced processing times by 40% when using General Electric, by 20% with Siemens, and by 18% with TeraRecon.

Conclusions

In conclusion, all three workstations facilitated precise assessment of dimensions in the majority of cases at simultaneously high reproducibility, ensuring accurate pre-interventional planning of thoracic endovascular aortic repair.

•

Pre-interventional planning of TEVAR in patients with TAAs using CTA is feasible.

•

All three workstations facilitated accurate measurements in vivo and ex vivo.

•

Repetition of measurements resulted in faster processing due to learning effects.

Quiescent-Interval Slice Selective Magnetic Resonance Angiography for Abdominal Aortic Aneurysm Treatment Planning

PURPOSE

Diagnostic imaging of Abdominal aortic aneurysm (AAA) almost exclusively employs CT angiography (CTA) involving X-ray exposure and contrast medium that may harm some patients. Quiescent-Interval Slice Selective MR (QISS-MR) depicts vascular anatomy without radiation or contrast medium. The diagnostic quality of QISS-MRA and CTA were compared in regard to length and diameter measurements in AAA patients. Suitability of QISS-MRA for AAA treatment planning was evaluated.

MATERIALS AND METHODS

The details of 30 patients with AAA who received both a QISS-MR and CTA for a known infrarenal AAA were obtained retrospectively that was approved by the local research ethics board. Two observers analyzed each dataset in terms of image quality and determined lumen diameter and length of 15 vessel segments.

RESULTS

Highly accurate agreement between the diagnostic scores from the two observers was achieved. There was no significant difference between CTA and QISS-MRA for all 15 measured vessels. Although information on calcification was lacking and intraluminal thrombus was visualized in only 25 patients out of 30 patients, a founded decision to carry out OR or EVAR was possible with both imaging modalities.

CONCLUSION

QISS-MRA presents a radiation and contrast free method for preoperative diagnostic AAA imaging. While QISS-MRA does not deliver exact information regarding calcification and thrombus formation, it does accurately allow measurement of vessel diameter and length. Therefore, it is potentially useful for EVAR planning in selected patients with impaired renal function.

[Therapy of Peripheral Artery Aneurysms]

Peripheral arterial aneurysms are rare vascular pathologies characterised by focal dilatation of at least 1.5-fold relative to the diameter of the native vessel. Primary arterial aneurysms can affect any segment of the arterial trunk. Diagnostic tests include duplex sonography, CT and MR angiography, and digital subtraction angiography. It is essential that the influx and efflux to the aneurysm should be mapped as precisely as possible. The most common type of peripheral arterial aneurysms are popliteal artery aneurysms, which frequently occur with aorta aneurysms. Peripheral arterial aneurysms are more common in patients with connective tissue disease or autoimmune disease (Ehlers-Danlos syndrome, Marfan syndrome, Behçet's disease). The current gold standard for therapy is surgery, although endovascular therapies have also been described. As the condition is rare, there is insufficient evidence to compare these approaches. Results from several register studies and single centre studies in patients with popliteal aneurysms indicate that endovascular therapy can give similar outcomes to open therapy if patients are carefully selected. Nevertheless, open surgery remains the gold standard. Therapy of aneurysms of the extremities must consider individual treatment criteria, such as the morphology of the aneurysm, its anatomical localisation - particularly with respect to mobilise segments, vascular efflux and the patient's general condition.

Dynamic 4D-CT Angiography for Guiding Transarterial Chemoembolization: Impact on the Reduction of Contrast Material, Operator Radiation Exposure, Catheter Consumption, and Diagnostic Confidence

PURPOSE

 This study was carried out to investigate the impact of abdominal dynamic four-dimensional CT angiography (4D-CTA) for guiding transarterial chemoembolization (TACE) on the amount of contrast material used, operator radiation exposure, catheter consumption, and diagnostic confidence.

MATERIALS AND METHODS

 Written consent was waived for this IRB-approved retrospective study. 29 patients (20 men; mean age: 65.7 ± 11.5 years) with malignant liver lesions underwent 4D-CTA, prior to initial TACE. Time-resolved volume-rendering technique (VRT), maximum-intensity projection (MIP), and multiplanar reconstruction (MPR) series were reconstructed, enabling a direct selective catheterization of the tumor-supplying artery without prior conventional digital subtraction angiography (DSA). 29 patients (16 men; mean age: 69.4 ± 13.9) who underwent traditional TACE served as the control group. The amount of administered contrast media, operator radiation exposure, and catheter consumption during TACE were compared. Two radiologists assessed diagnostic confidence in the exclusion of portal vein thrombosis.

RESULTS

 4D-CTA TACE resulted in a significant reduction in the amount of contrast media used, compared to traditional TACE (-61.0 ml/ -66.3 % intra-arterial, -12.8 ml/ -13.8 % overall; P < 0.001). The dose-area product indicating operator radiation exposure during intervention was reduced by 50.5 % (P < 0.001), and 0.7 fewer catheters on average were used (P = 0.063), while 4D-CTA data was available to guide TACE. Diagnostic confidence in the exclusion of portal vein thrombosis was significantly enhanced by 4D-CTA, compared to traditional DSA images (scores, 3.9 and 2.4, respectively; P < 0.001).

CONCLUSION

 Dynamic 4D-CTA enables TACE with a substantially reduced amount of contrast material, decreases operator radiation exposure, and increases diagnostic confidence in the exclusion of portal vein thrombosis.

KEY POINTS

  · 4D-CTA prior to TACE decreases the amount of utilized contrast material.. · The intra-arterial fraction of contrast media can be reduced by two-thirds.. · The risk of CIN may be decreased by means of 4D-CTA TACE.. · Operator radiation exposure is lower using 4D-CTA for guiding TACE.. · 4D-CTA portography allows for a higher diagnostic confidence than conventional DSA images..

CITATION FORMAT

· Albrecht MH, Vogl TJ, Wichmann JL et al. Dynamic 4D-CT Angiography for Guiding Transarterial Chemoembolization: Impact on the Reduction of Contrast Material, Operator Radiation Exposure, Catheter Consumption, and Diagnostic Confidence. Fortschr Röntgenstr 2018; 190: 513 - 520.

Assessment of the cochlear nerve to facial nerve size ratio using MR multiplanar reconstruction of the internal auditory canal in patients presenting with acquired long-standing hearing loss

OBJECTIVE

To test using the facial nerve as a reference for assessment of the cochlear nerve size in patients with acquired long-standing sensorineural hearing loss (SNHL) using MRI multiplanar reconstruction.

METHODS

The study was retrospectively performed on 86 patients. Group 1 (study group, n = 53) with bilateral long-standing SNHL. Group 2 (control group, n = 33) without hearing loss. The nerve size was measured by drawing a region of interest around the cross-sectional circumference of the nerve in multiplanar reconstruction images.

RESULTS

No significant correlation was noted between the cochlear nerve and facial nerve size, and the patient's age, gender and weight (p > 0.05). In Group 1, the mean ratio of the cochlear to facial nerve size was 0.99 ± 0.30 (range: 0.52-1.86) and 1.12 ± 0.35 (range: 0.34-2.3) for the right and left sides, respectively. In Group 2, it was 1.18 ± 0.23 (range: 0.78-1.71) and 1.25 ± 0.25 (range: 0.85-1.94) for the right and left sides, respectively. The cochlear nerve size was statistically (p = 0.0004) smaller in Group 1 than in Group 2.

CONCLUSION

The cochlear nerve size and the cochlear to facial nerve size ratio are significantly smaller in patients with acquired long-standing SNHL. Advances in knowledge: The facial nerve can be used as a reference for assessment of the cochlear nerve in patients with acquired long-standing SNHL.

Vismodegib hedgehog-signaling inhibition and treatment of basal cell carcinomas as well as keratocystic odontogenic tumors in Gorlin syndrome

Vismodegib hedgehog signaling inhibition treatment has potential for reducing the burden of multiple skin basal cell carcinomas and jaw keratocystic odontogenic tumors. They are major criteria for the diagnosis of Gorlin syndrome, also called nevoid basal cell carcinoma syndrome. Clinical features of Gorlin syndrome are reported, and the relevance of hedgehog signaling pathway inhibition by oral vismodegib for maxillofacial surgeons is highlighted. In summary, progressed basal cell carcinoma lesions are virtually inoperable. Keratocystic odontogenic tumors have an aggressive behavior including rapid growth and extension into adjacent tissues. Interestingly, nearly complete regression of multiple Gorlin syndrome-associated keratocystic odontogenic tumors following treatment with vismodegib. Due to radio-hypersensitivity in Gorlin syndrome, avoidance of treatment by radiotherapy is strongly recommended for all affected individuals. Vismodegib can help in those instances where radiation is contra-indicated, or the lesions are inoperable. The effect of vismodegib on basal cell carcinomas was associated with a significant decrease in hedgehog-signaling and tumor proliferation. Vismodegib, a new and approved drug for the treatment of advanced basal cell carcinoma, is a specific oncogene inhibitor. It also seems to be effective for treatment of keratocystic odontogenic tumors and basal cell carcinomas in Gorlin syndrome, rendering the surgical resections less challenging.

Transarterial chemoembolization of unresectable systemic chemotherapy-refractory liver metastases from colorectal cancer: long-term results over a 10-year period

The aims of the study were to evaluate therapeutic efficacy and to determine the prognostic factors for treatment success in patients with liver metastases from colorectal cancer (CRC) treated with transarterial chemoembolization (TACE). A total of 564 patients (mean age, 60.3 years) with liver metastases of CRC were repeatedly treated with TACE. In total, 3,384 TACE procedures were performed (mean, six sessions per patient). The local chemotherapy protocol consisted of mitomycin C alone (43.1%), mitomycin C with gemcitabine (27.1%), mitomycin C with irinotecan (15.6%) or mitomycin C with irinotecan and cisplatin (15.6%). Embolization was performed with lipiodol and starch microspheres. Tumor response was evaluated using magnetic resonance imaging or computed tomography. The change in tumor size was calculated and the response was evaluated according to the RECIST-Criteria. Survival rates were calculated according to the Kaplan-Meier method. Prognostic factors for patient's survival were evaluated using log-rank test. Evaluation of local tumor control showed partial response in 16.7%, stable disease in 48.2% and progressive disease in 16.7%. The 1-year survival rate after chemoembolization was 62%, the 2-year survival rate was 28% and the 3-year survival rate was 7%. Median survival from the start of chemoembolization treatment was 14.3 months. The indication (p = 0.001) and initial tumor response (p = 0.015) were statistically significant factors for patient's survival. TACE is a minimally invasive therapy option for controlling local metastases and improving survival time in patients with hepatic metastases from CRC. TN stage, extrahepatic metastases, number of lesions, tumor location within the liver and choice of chemotherapy protocol of TACE are none significant factors for patient's survival.

Pediatric primary and metastatic neuroblastoma: MRI findings: pictorial review

Magnetic resonance imaging (MRI) has become one of the most valuable modalities for initial and follow-up imaging of suspected or known neuroblastoma (NBL) owing to its excellent inherent contrast, lack of ionizing radiation and multiplanar imaging capability. Importantly, NBL has a variable appearance on different imaging modalities, and this is particularly pertinent to MRI. MRI is a cornerstone for management of NBL, providing essential information at initial presentation regarding diagnosis, staging, resectability and relation to vital structures. It can also define the extent of residual disease after surgical resection or assess the efficacy of treatment. Follow-up MRI is frequently performed to ensure sustained complete remission or to monitor known residual disease. This pictorial review article aims to provide the reader with a concise, yet comprehensive, collection of MR images of primary and metastatic NBL lesions with relevant correlation with other imaging modalities.

Different imaging techniques in the head and neck: Assets and drawbacks

In this review, the gold standard imaging techniques for the head and neck and the latest upcoming techniques are presented, by comparing computed tomography (CT), magnetic resonance imaging and positron emission tomography-CT, as well as ultrasound, depending on the examined area. The advantages and disadvantages of each examination protocol are presented. This article illustrates the connection between the imaging technique and the examined area. Therefore, the head and neck area is divided into different sections such as bony structures, nervous system, mucous membranes and squamous epithelium, glandular tissue, and lymphatic tissue and vessels. Finally, the latest techniques in the field of head and neck imaging such as multidetector CT, dual-energy CT, flash CT, magnetic resonance angiography, spectroscopy, and diffusion tensor tractography using 3 tesla magnetic resonance are discussed.

Autoimmune pancreatitis in an 11-year-old boy

We report a case of histopathologically proven autoimmune pancreatitis in an 11-year-old boy. Abdominal US and MRI showed a focal swelling of the pancreatic head, the latter also showing delayed contrast enhancement. There was diffuse irregular pancreatic duct narrowing, compression of the intrapancreatic common bile duct, and mild proximal biliary dilatation on MR cholangiopancreatography. Laboratory results revealed normal serum IgG and subclass 4 with negative autoimmune antibodies, and slightly elevated carbohydrate antigen 19-9. This highlights the differentiation of autoimmune pancreatitis from pancreatic head cancer and, to a lesser extent, other forms of pancreatitis in children.

Automated Detection of Lung Nodules in Multidetector CT: Influence of Different Reconstruction Protocols on Performance of a Software Prototype

PURPOSE

To evaluate the accuracy of software for computer-aided detection (CAD) of lung nodules using different reconstruction slice thickness protocols in multidetector CT.

MATERIALS AND METHODS

Raw image data sets for 15 patients who had undergone 16-row multidetector CT (MDCT) for known pulmonary nodules were reconstructed at a reconstruction thickness of 5.0, 2.0 and 1.0 mm with a reconstruction increment of 1.5, 1.0 and 0.5 mm, respectively. The "Nodule Enhanced Viewing" (NEV) tool of LungCare for computer-aided detection of lung nodules was applied to the reconstructed images. The reconstructed images were also blinded and then evaluated by 2 radiologists (A and B). Data from the evaluating radiologists and CAD was then compared to an independent reference standard established using the consensus of 2 independent experienced chest radiologists. The eligible nodules were grouped according to their size (diameter > 10, 5 - 10, < 5 mm) for assessment. Statistical analysis was performed using the receiver operating characteristic (ROC) curve analysis, t-test and two-rater Cohen's Kappa co-efficient.

RESULTS

A total of 103 nodules were included in the reference standard by the consensus panel. The performance of CAD was marginally lower than that of readers at a 5.0-mm reconstruction thickness (AUC = 0.522, 0.517 and 0.497 for A, B and CAD, respectively). In the case of 2.0-mm reconstruction slices, the performance of CAD was better than that of the readers (AUC = 0.524, 0.524 and 0.614 for A, B and CAD, respectively). CAD was found to be significantly superior to radiologists in the case of 1.0-mm reconstruction slices (AUC = 0.537, 0.531 and 0.675 for A, B and CAD, respectively). The sensitivity at a reconstruction thickness of 1.0 mm was determined to be 66.99 %, 68.93 % and 80.58 % for A, B and CAD, respectively. The time required for detection was shortest for CAD at reconstruction slices of 1.0 mm (mean t = 4 min). The performance of radiologists was greatly enhanced when using CAD: sensitivity 91.26 % and 94.17 % for CAD+A and CAD+B, respectively (AUC = 0.889 and 0.917). CAD was most advantageous in the detection of nodules < 10 mm.

CONCLUSION

At a 1.0-mm reconstruction thickness, CAD's ability to detect nodules < 10 mm is superior to that of radiologists and its relatively short evaluation time makes it a viable second reader.

Virtual endoscopy of the tracheo-bronchial system: sub-millimeter collimation with the 16-row multidetector scanner

The purpose of this study was to evaluate the scope of sub-millimeter collimation reconstruction parameters using 16-row computer tomography and ECG triggering on image quality in virtual bronchoscopy. Thirty-two patients (5 women, 27 men, mean age 66.6+/-1.4) who had been admitted for coronary artery bypass graft surgery underwent CT examination of the thorax (Sensation 16, Siemens, Inc., Forchheim, Germany). All patients were examined with 16x0.75-mm collimation. Image reconstruction was performed for two groups. In group A ( n=32), slice thickness of 1.5 mm and an overlap of 0.75 mm were used. In group B ( n=32), slice thickness of 0.75 mm and an overlap of 0.4 mm were applied. Retrospective ECG triggering was performed in all patients. The maximum order of recognizable bronchi was determined in each data set. In addition to assessing the maximum order of bronchial bifurcation, bronchial diameter was determined in truly perpendicular sections in each patient. For every segment proximal to a bifurcation, image quality was subjectively graded as poor (grade 1), moderate (grade 2) or good (grade 3). The observers were asked to identify the minimum cardiac movement ECG-triggered image sets assuming that they would be of better quality than the maximum cardiac movement ECG-triggered image sets. The Mann-Whitney U-test and the Fisher's Exact Test were used for statistical evaluation. In group A, a mean of 4.8+/-0.2 bifurcations was ascertained vs. 6.5+/-0.3 bifurcations in group B [ P<0.0003]. For bronchial diameters in group A, a mean of 7.5+/-0.4 mm was determined vs. 4.6+/-0.4 mm in group B [ P<0.0001]. In group B, two independent radiologists observed a significant shift to better image quality in all segments evaluated [ P<0.006 to P<0.000001]. Motion artifacts were judged as being significantly reduced by minimum cardiac movement ECG-triggering in group B [observer 1: P=0.0007 (20/32); observer 2: P=0.008 (18/32)], but not in group A [observer 1: P=0.286 (13/32); observer 2: P=0.123 (16/32)]. Sub-millimeter collimation and minimum cardiac movement ECG-triggered data acquisition allow deeper penetration into the tracheo-bronchial system allowing visualization of the bronchial surface down to diameters below 5 mm in certain cases up to the eighth bifurcation. Along with an enhanced visualization as such, better image quality is acquired in all segments evaluated. Trade off between better image quality, of doubtful diagnostic consequence, and much higher irradiation dose must be made.

Vitamin D levels in women with systemic lupus erythematosus and fibromyalgia

OBJECTIVE

Many patients with systemic lupus erythematosus (SLE) and fibromyalgia (FM) may spend less time exposed to the sun than healthy individuals and thus might have low vitamin D levels. It is known that hydroxychloroquine (HCQ) inhibits conversion of 25(OH)- to 1,25(OH)2-vitamin D both in vitro and in patients with sarcoidosis. We assessed winter serum 25(OH)- and 1,25(OH)2-vitamin D levels in patients with SLE and FM.

METHODS

We recruited 25 consecutive female SLE and 25 female FM patients in London, Ontario, between January and March 2000. Subjects completed a brief questionnaire. Serum levels of 25(OH)-, 1,25(OH)2-vitamin D, and parathyroid hormone (PTH) were measured.

RESULTS

In SLE patients mean 25(OH)-vitamin D was 46.5 nmol/l and mean 1,25(OH)2-vitamin D was 74.4 pmol/l. In FM patients these means were 51.5 nmol/l and 90.1 pmol/l, respectively. Serum 25(OH)-vitamin D levels did not significantly differ between SLE and FM patients, nor after adjusting for age and vitamin D, milk consumption, and sun block use. In 14 of the SLE patients and 12 of the FM patients 25(OH)-vitamin D levels < 50 nmol/l were found. SLE patients not using vitamin D supplements had lower 25(OH)-vitamin D levels than those who did. 1,25(OH)2-vitamin D tended to be lower in the SLE compared to the FM patients. This difference could be attributed to HCQ use: HCQ users (n = 17) had lower 1,25(OH)2-vitamin D levels than nonusers (n = 33); the mean adjusted difference was 24.4 pmol/l (95% CI 2.8-49.9).

CONCLUSION

Half the SLE and FM patients had 25(OH)-vitamin D levels < 50 nmol/l, a level at which PTH stimulation occurs. Our data suggest that in SLE patients HCQ might inhibit conversion of 25(OH)-vitamin D to 1,25(OH)2-vitamin D.

Classification, epidemiology, and natural history of fibromyalgia

Fibromyalgia (FM), also known as fibromyalgia syndrome (FMS) and fibrositis, is a common form of nonarticular rheumatism that is associated with chronic generalized musculoskeletal pain, fatigue, and a long list of other complaints. Some have criticized the classification of FM as a distinct medical entity, but existing data suggest that individuals meeting the case definition for FM are clinically somewhat distinct from those with chronic widespread pain who do not meet the full FM definition. Clinic studies have found FM to be common in countries worldwide; these include studies in specialty and general clinics. The same is true of general population studies, which show the prevalence of FM to be between 0.5% and 5%. Knowledge about risk factors for FM is limited. Females are at greater risk, and risk appears to increase through middle age, then decline. Although some authors claim that an epidemic of FM has been fueled by an over-generous Western compensation system, there are no data that demonstrate an increasing incidence or prevalence of FM; moreover, existing data refute any association between FM prevalence and compensation. Claims that the FM label itself causes illness behavior and increased dependence on the medical system also are not supported by existing research. This article reviews the classification, epidemiology, and natural history of FM.

Lumbar pannus presenting as cauda equina syndrome in a patient with longstanding rheumatoid arthritis

Relatively little attention has been paid to lumbar spine involvement in rheumatoid arthritis (RA), and indeed it is generally considered to be an uncommon and usually clinically minor manifestation of the disease. We describe a case of acute right lower extremity weakness secondary to compression of multiple lumbar nerve roots by a large interforaminal rheumatoid pannus, and review the literature on this complication and other lumbar spine involvement in RA.

High-level, but not low-level, occupational exposure to inhaled anesthetics is associated with genotoxicity in the micronucleus assay

To minimize the possible health risks posed by waste anesthetic gases, the National Institute of Occupational Safety and Health (NIOSH) recommends exposure limits. We investigated the genotoxicity of a previously established occupational exposure exceeding these limits (high-level exposure) and of one within these limits (low-level exposure). Genotoxicity was assessed by the formation of micronucleated lymphocytes in 25 anesthetists and anesthetic nurses of an Eastern European (High-Level Exposure Group) and a German (Low-Level Exposure Group) university hospital. Each exposed group was compared with a group of nonexposed personnel of the same hospital. Compared with its Control Group, there was an increased fraction of micronucleated lymphocytes per 1000 binucleated cells in the High-Level Exposure Group (median 14.0, range 9.0-26.7 vs median 11.3, range 3.2-19.4; P < 0.05) but not in the Low-Level Exposure Group (median 9.8, range 4.2-20.0 vs median 10.5, range 5.0-20.5). We conclude that a high-level exposure to inhaled anesthetics is associated with an increase in chromosome damage, and measures are recommended to decrease exposure levels. As evidenced by the formation of micronucleated lymphocytes, the threshold values recommended by NIOSH appear to be safe.

IMPLICATIONS

A high level of occupational exposure to inhaled anesthetics is associated with genotoxicity (as defined by formation of micronucleated lymphocytes), whereas a low-level exposure (within National Institute of Occupational Safety and Health limits) is not.

A follow-up study on occupational exposure to inhaled anaesthetics in Eastern European surgeons and circulating nurses

OBJECTIVE

Although no dose-response relationship exists for the health risks associated with the occupational exposure to inhaled anaesthetics, public health authorities recommend threshold values. The aim of the present study was to assess whether and to what extent these threshold values are exceeded in surgeons and circulating nurses of an Eastern European university hospital, before and after measures had been taken to reduce occupational exposure.

METHODS

At nine workplaces, occupational exposure to nitrous oxide and the volatile anaesthetic used (halothane or isoflurane) was measured within the breathing zones of surgeons and circulating nurses by means of photoacoustic infrared spectrometry. The measurements were carried out in 1996 and were repeated in 1997 after the installation of active scavenging devices at five workplaces, and an air-conditioning system at one workplace.

RESULTS

Occupational exposure to nitrous oxide and halothane or isoflurane was lower in 1997 compared with that of 1996. In 1996, 89% of the nitrous oxide values were above the European threshold value of 100 ppm, whereas in 1997 approximately 50% were above this limit. In 1996 the majority of the measurements for the volatile anaesthetics were already below 5 ppm halothane and 10 ppm isoflurane and the number of measurements exceeding these limits was further reduced in 1997.

CONCLUSION

The measures taken were effective in reducing waste gas exposure. Nevertheless, further efforts are necessary, especially for nitrous oxide, to reach Western European standards and to minimise possible health risks. These efforts comprise the installation of (active) scavenging devices, air-conditioning systems and new anaesthesia machines at all workplaces, the use of low-flow anaesthesia, the replacement of inhaled anaesthetics by intravenous anaesthetics and an appropriate working technique.

A general population study of fibromyalgia tender points in noninstitutionalized adults with chronic widespread pain

OBJECTIVE

To assess the distribution and predictive ability of fibromyalgia (FM) tender points (TP) in adults with chronic widespread pain.

METHODS

Using published classification criteria, we confirmed 100 FM cases and 76 controls with widespread pain not meeting the 1990 American College of Rheumatology (ACR) classification criteria for FM (pain controls) in a survey of 3,395 adults screened for widespread musculoskeletal pain in a general population survey.

RESULTS

At each of the 18 FM tender points, FM cases were more likely than pain controls to have tenderness, and the likelihood ratio (LR) was statistically greater than 1.0 for 13 of 18 points. However, the LR for individual points ranged from 4.0 to as low as 1.2. Females were more likely to have TP, especially at lower body points; however, lower body points were more discriminatory in males.

CONCLUSION

TP differ in their ability to predict FM among adults in the general population with chronic widespread pain.

Occupational exposure to inhaled anaesthetics: a follow-up study on anaesthetists of an eastern European university hospital

BACKGROUND

Although no dose-response relationship for the health risks associated with the occupational exposure to inhaled anaesthetics exists, public health authorities recommend threshold values. The aim of the present study was to assess if and to what extent these threshold values are exceeded in an eastern European university hospital before and after measures had been taken to reduce occupational exposure.

METHODS

At nine workplaces occupational exposure of anaesthetists to nitrous oxide and halothane or isoflurane was measured by means of photoacoustic infrared spectrometry. The measurements were carried out in 1996 and were repeated in 1997 after the installation of active scavenging devices at five workplaces and an air-conditioning system at one workplace.

RESULTS

Occupational exposure to nitrous oxide and halothane or isoflurane was lower in 1997 compared to 1996. In 1997 most of the nitrous oxide values still exceeded the threshold value of 100 ppm, whereas most of the halothane and isoflurane values were already below the threshold values of 5 ppm and 10 ppm in 1996.

CONCLUSION

The measures taken were effective in reducing waste gas exposure. Nevertheless, further efforts are necessary, especially for nitrous oxide, to reach western European standards. These efforts comprise structural measures such as active scavenging devices and air-conditioning systems at all workplaces, the use of total intravenous anaesthesia, low-flow anaesthesia and an appropriate working technique.

Co-existence of chronic fatigue syndrome with fibromyalgia syndrome in the general population. A controlled study

OBJECTIVE

To determine the proportion of adults with fibromyalgia syndrome (FMS) in the general population who also meet the 1988 Centre for Disease Control (CDC) criteria for chronic fatigue syndrome (CFS).

METHODS

Seventy-four FMS cases were compared with 32 non-FMS controls with widespread pain and 23 with localized pain, all recruited in a general population survey.

RESULTS

Among females, 58.0% of fibromyalgia cases met the full criteria for CFS, compared to 26.1% and 12.5% of controls with widespread and localized pain, respectively (p=0.0006). Male percentages were 80.0, 22.2, and zero, respectively (p=0.003). Compared to those with FMS alone, those meeting the case definitions for both FMS and CFS reported a worse course, worse overall health, more dissatisfaction with health, more non-CFS symptoms, and greater disease impact. The number of total symptoms and non-CFS symptoms were the best predictors of co-morbid CFS.

CONCLUSIONS

There is significant clinical overlap between CFS and FMS.

Perspectives on posttraumatic fibromyalgia: a random survey of Canadian general practitioners, orthopedists, physiatrists, and rheumatologists

OBJECTIVE

To determine which factors physicians consider important in patients with chronic generalized posttraumatic pain.

METHODS

Using physician membership directories, random samples of 287 Canadian general practitioners, 160 orthopedists, 160 physiatrists, and 160 rheumatologists were surveyed. Each subject was mailed a case scenario describing a 45-year-old woman who sustained a whiplash injury and subsequently developed chronic, generalized pain, fatigue, sleep difficulties, and diffuse muscle tenderness. Respondents were asked whether they agreed with a diagnosis of fibromyalgia (FM), and what factors they considered to be important in the development of chronic, generalized posttraumatic pain.

RESULTS

More-recent medical school graduates were more likely to agree with the FM diagnosis. Orthopedists (28.8%) were least likely to agree, while rheumatologists (83.0%) were most likely to agree. On multivariate analysis, 5 factors predicted agreement or disagreement with the diagnosis of FM: (1) number of FM cases diagnosed by the respondent per week (p < 0.0001); (2) patient's sex (p < 0.0001); (3) force of initial impact (p = 0.003); (4) patient's pre-collision psychiatric history (p = 0.03); and (5) severity of initial injuries (p = 0.03). The force of initial impact and the patient's pre-collision psychiatric history were both negatively correlated with agreement in diagnosis. Patient related factors (personality, emotional stress, pre-collision physical, mental health) were considered more important than trauma related factors in the development of chronic, widespread pain.

CONCLUSION

Future studies of the association between trauma and FM should identify potential cases outside of specialty clinics, and baseline assessments should include some measurement of personality, stress, and pre-collision physical and mental health.

Trauma and fibromyalgia: is there an association and what does it mean?

OBJECTIVES

The primary objective is to review current research with respect to the role of trauma in fibromyalgia (FM). A secondary objective is to hypothesize which steps need to be taken, first to determine whether such an association truly exists, and second to clarify what such an association might mean.

METHODS

An extensive literature review was undertaken, including Medline from 1979 to the present.

RESULTS

The strongest evidence supporting an association between trauma and FM is a recently published Israeli study in which adults with neck injuries had greater than a 10-fold increased risk of developing FM within 1 year of their injury, compared with adults with lower extremity fractures (P= .001). Several other studies provide a hypothetical construct for such an association. These include studies on (1) postinjury sleep abnormalities; (2) local injury sites as a source of chronic distant regional pain; and (3) the concept of neuroplasticity. There are, however, several primary arguments against such an association: (1) FM may not be a distinct clinical entity; (2) FM may be a psychological, rather than physical, disease; (3) the evidence supporting any association is limited and not definitive; (4) the Israeli study, itself, has some methodological limitations; and (5) other factors may be more important than the injurious event in determining chronic symptoms after an acute injury.

CONCLUSIONS

Although there is some evidence supporting an association between trauma and FM, the evidence is not definitive. Further prospective studies are needed to confirm this association and to identify whether trauma has a causal role.

The occurrence and impact of generalized pain

A major problem with estimating the impact of chronic generalized pain is that the term remains undefined. It appears to encompass several distinct clinical entities, including rheumatoid arthritis and fibromyalgia, which can exist alone or together in a given individual. Nonetheless, chronic generalized pain appears to have a sizable impact on both the individual and society. Although little is known about causal relationships, demographic risk factors for chronic generalized pain are female sex, age in the forties and fifties, lower income, lower education, and being divorced or separated. Chronic generalized pain affects the individual in several ways, including physical and psychological distress, losses of function, quality of life, employment and income, and prolonged litigation for many. Its impact on society includes increased utilization of health care resources, loss of work productivity, disability and insurance costs, costs of litigation and social policy. Future research into the impact of chronic generalized pain must begin by defining this term in a way that is both valid in construct and convenient to use. Research is also warranted to develop and validate diagnostic tools that may better distinguish various subsets of chronic generalized pain, both to better understand the pathological processes involved and to allow for estimates of the relative contribution of each subset to societal costs.

The London Fibromyalgia Epidemiology Study: comparing the demographic and clinical characteristics in 100 random community cases of fibromyalgia versus controls

OBJECTIVE

To identify demographic and clinical features that distinguish fibromyalgia (FM) from other chronic widespread pain.

METHODS

We identified 100 confirmed FM cases, 76 widespread pain controls, and 135 general controls in a random community survey of 3395 noninstitutionalized adults living in London, Ontario. FM cases were distinguished from pain controls using the 1990 American College of Rheumatology (ACR) classification criteria for FM.

RESULTS

The mean age of FM cases was 47.8 years (range 19 to 86), the same as for pain controls; 86% of FM cases were female versus 67.1% of pain controls (p < 0.01). FM cases were less educated than general controls (p = 0.03). Male and female FM cases were similar, except females were older and reported more major symptoms (both p = 0.02). FM cases reported more severe pain and fatigue, more symptoms, more major symptoms, and worse overall health than pain controls or general controls. The most commonly reported major symptoms among FM cases were musculoskeletal pain (77.3%), fatigue (77.3%), severe fatigue lasting 24 h after minimal activity (77.0%), nonrestorative sleep (65.7%), and insomnia (56.0%). Subjects with 11-14 tender points were more similar to those with 15-18 tender points than to those with 7-10 points in 11 of 14 clinical variables. On multivariate analysis, 4 symptoms distinguished FM cases from pain controls: pain severity (p = 0.004), severe fatigue lasting 24 h after minimal activity (p = 0.006), weakness (p = 0.008), and self-reported swelling of neck glands (p = 0.01).

CONCLUSION

In the general population, adults who meet the ACR definition of FM appear to have distinct features compared to those with chronic widespread pain who do not meet criteria.