Faculty Bibliography

OBJECTIVE: The objective of our study was to help clarify the role of CT-guided pudendal nerve blocks in the problematic and poorly understood entity of pudendal neuralgia (PN). SUBJECTS AND METHODS: Over a 1-year period, 52 CT-guided pudendal nerve blocks were performed in 31 patients (28 women, three men; age range, 22-80 years) who suffered from chronic pelvic pain with a presumed diagnosis of PN. A combination of anesthetic and steroid was injected into the pudendal (Alcock) canal. Pre- and postprocedural pain scores (0-10) were tallied and assessed by Student t tests. A p value < 0.05 was indicative of a significant difference. RESULTS: All procedures were successful technically, which was defined as contrast material filling the pudendal canal on CT and subsequent infusion of anesthetic and steroid. Pre- and postprocedural pain scores ranged from 2 to 10 (mean score, 6.13) and 0-10 (mean score, 2.14), respectively; the difference was statistically significant for each nerve block session (first session, p < 0.001; second session, p < 0.001; third session, p = 0.049). Of the 31 patients, two had long-term relief with pudendal nerve blocks alone. Fourteen had subsequent surgery based on initial improvement with block(s), and all 14 patients improved with surgical nerve release. Two patients had no diagnostic response and the diagnosis of PN was excluded. The gynecologic service followed the remaining 13 patients clinically. CONCLUSION: CT-guided pudendal nerve blocks appear to be valuable diagnostically for PN and uncommonly therapeutically. On the basis of these preliminary results, we have developed an algorithm for the role of the procedure for PN.

OBJECTIVE: Dural venous sinus abnormalities are clinically important but can potentially be overlooked using various MRI techniques. This study evaluates the diagnostic accuracy of spin-echo (SE) T1-weighted imaging, 3D gradient-recalled echo (GRE) T1-weighted imaging, and contrast-enhanced MR venography (MRV) for the detection of dural venous sinus thrombosis and transverse sinus (TS) stenosis. MATERIALS AND METHODS: Seventy-three patients underwent MRI evaluation with unenhanced and contrast-enhanced axial SE T1-weighted imaging, contrast-enhanced sagittal 3D GRE T1-weighted imaging, and contrast-enhanced MRV sequences. Three neuroradiologists each evaluated these 219 total datasets in a randomized blinded fashion for the presence or absence of TS stenosis and for dural venous sinus thrombosis in each of 10 venous sinus segments (730 total segments). Diagnostic performance characteristics and kappa statistics were calculated for each technique. RESULTS: Thirteen patients (37 segments) had suspected dural venous sinus thrombosis by one or more readers; of those 13 patients, nine (23 segments) were thought to have definite thrombosis on contrast-enhanced MRV. Compared with contrast-enhanced MRV, the positive predictive value (PPV) and negative predictive value (NPV) for thrombosis were 60% and 97%, respectively, for both unenhanced and contrast-enhanced SE T1-weighted imaging and 100% and 98% for 3D GRE T1-weighted imaging. Kappa values calculated per venous segment were as follows: 0.41 for SE T1-weighted imaging, 0.72 for 3D GRE T1-weighted imaging, and 0.95 for contrast-enhanced MRV. Thirty patients (58 segments) had TS stenosis suspected by one or more readers; of those 30 patients, TS stenosis was deemed to be definite on contrast-enhanced MRV in 25 patients (50 segments). Compared with contrast-enhanced MRV, the PPV and NPV were 75% and 80%, respectively, for SE T1-weighted imaging and 91% and 92% for 3D GRE T1-weighted imaging for the detection of stenosis. Kappa values calculated per patient were -0.038 for SE T1-weighted imaging, 0.58 for 3D GRE T1-weighted imaging, and 0.98 for contrast-enhanced MRV. CONCLUSION: Contrast-enhanced 3D GRE T1-weighted imaging is superior to SE T1-weighted imaging for the detection of dural venous sinus thrombosis and TS stenosis but does not substitute for dedicated MRV. Hyperintensity on unenhanced SE T1-weighted imaging is unreliable for the detection of dural venous sinus thrombosis.

Stenosis of a DVA may result in chronic venous ischemia. We present 6 patients (3 men, 3 women; age range, 30-79 years; mean age, 53 years) with unilateral calcification of the caudate and putamen on noncontrast CT. This calcification typically spared the anterior limb of the internal capsule. No patient presented with symptoms referable to the basal ganglia or had an underlying metabolic disorder or other process associated with calcium deposition. All patients subsequently underwent gadolinium-enhanced MR imaging and/or CTA or conventional angiography demonstrating the presence of an adjacent DVA. We hypothesize that chronic venous ischemia in the drainage territory of the DVA causes the abnormal mineralization. Greater recognition of this entity will prevent misinterpretation of this finding as acute hemorrhage and will prevent unnecessary and sometimes invasive evaluation in such patients. Furthermore, this entity should be considered in the differential diagnosis of unilateral basal ganglia hyperattenuation.

BACKGROUND: Skin diseases and their complications are a significant burden on the nation, both in terms of acute and chronic morbidities and their related expenditures for care. Because accurately calculating the cost of skin disease has proven difficult in the past, we present here multiple comparative techniques allowing a more expanded approach to estimating the overall economic burden. OBJECTIVES: Our aims were to (1) determine the economic burden of primary diseases falling within the realm of skin disease, as defined by modern clinical disease classification schemes and (2) identify the specific contribution of each component of costs to the overall expense. METHODS: Costs were taken as the sum of several factors, divided into direct and indirect health care costs. The direct costs included inpatient hospital costs, ambulatory visit costs (further divided into physician's office visits, outpatient department visits, and emergency department visits), prescription drug costs, and self-care/over-the-counter drug costs. Indirect costs were calculated as the outlay of days of work lost because of skin diseases. RESULTS: The economic burden of skin disease in the United States is large, estimated at approximately $35.9 billion for 1997, including $19.8 billion (54%) in ambulatory care costs; $7.2 billion (20.2%) in hospital inpatient charges; $3.0 billion (8.2%) in prescription drug costs; $4.3 billion (11.7%) in over-the-counter preparations; and $1.6 billion (6.0%) in indirect costs attributable to lost workdays. CONCLUSIONS: Our determination of the economic burden of skin care in the United States surpasses past estimates several-fold, and the model presented for calculating cost of illness allows for tracking changes in national expenses for skin care in future studies. The amount of estimated resources devoted to skin disease management is far more than required to treat conditions such as urinary incontinence ($16 billion) and hypertension ($23 billion), but far less than required to treat musculoskeletal conditions ($193 billion).

BACKGROUND: Research has found that among health care workers, dental personnel are especially likely to have reactions to glutaraldehyde and formaldehyde. METHODS: The authors conducted patch test evaluations with a voluntary cohort of randomly recruited, healthy dental hygienists, or DHs, and dental assistants, or DAs, and nondental professionals to determine the incidence of glutaraldehyde-induced and formaldehyde-induced allergic contact dermatitis, or ACD; the potential for coreactivity between glutaraldehyde and formaldehyde; and the correlation between training methods in safe handling of sterilizing solutions and the sensitivity to glutaraldehyde and formaldehyde among DHs and DAs. RESULTS: The researchers enrolled 101 DHs and DAs and 51 nondental professionals in the study. All except one DH/DA subject were female. The dental subjects' mean age was 34.3 +/- standard deviation of 10.7 years; the nondental subjects', 33.8 +/- 11.0 years. DHs and DAs had worked in their profession for a mean of 11.0 +/- 9.3 years. Among the dental professionals, 80 (79.2 percent) had had a known exposure to cold sterilizing solutions, while the remainder were unable to provide a known history of exposure. Eleven (10.9 percent) dental professionals had clear reactions to glutaraldehyde, four (4.0 percent) were questionably allergic to glutaraldehyde, and two (2 percent) were definitively allergic to formaldehyde. One (2 percent) control subject had a reaction to glutaraldehyde, and one other (2 percent) had a reaction to formaldehyde. CONCLUSIONS AND CLINICAL: IMPLICATIONS: The authors found a statistically significant disparity in the rates of glutaraldehyde sensitivity among healthy DHs and DAs versus healthy control subjects (10.9 percent versus 2 percent reactively; P = .02). They found no evidence of cross-reactivity between glutaraldehyde and formaldehyde. The preponderance of reactions among the DHs and DAs suggests that their present safety practices are largely ineffective in protecting against sensitization to glutaraldehyde in sterilizing solutions