Michael I. Rothman

Transcranial Doppler detection of vertebrobasilar vasospasm following subarachnoid hemorrhage.

Transcranial Doppler sonography is of established value in the detection and monitoring of middle cerebral artery vasospasm. Little information exists on the utility of transcranial Doppler for detection of posterior circulation vasospasm. Methods Cerebral angiography and conventional handheld transcranial Doppler sonography were compared to determine sensitivity and specificity of transcranial Doppler for detection of vertebral and basilar artery vasospasm. Results Of 59 consecutive subarachnoid hemorrhage patients with transcranial Doppler angiogram correlations, 42 underwent posterior circulation angiography to evaluate 64 vertebral arteries and 42 basilar arteries during the period of risk for vasospasm and had technically adequate transcranial Doppler examinations within 24 hours of the angiogram. A mean flow velocity of 60 cm/s and above was indicative of both vertebral and basilar artery vasospasm. For the vertebral artery, there were 7 true-positive test results, 42 true-negatives, 6 false-positives (unknown cause in 3, increased collateral flow in 1, adjacent vessel vasospasm in 1, hyperperfusion in 1), and 9 false-negatives (anatomic in 7, operator error in 2). Sensitivity was 44% and specificity was 87.5%. For the basilar artery, there were 10 true-positives, 23 true-negatives, 6 falsepositives (unknown cause in 4, hyperemia/hyperperfusion in 1, increased collateral flow in 1), and 3 false-negatives (operator error in 2, tortuous vessel course in 1). Sensitivity was 76.9% and specificity was 79.3%. When the diagnostic criterion was changed to ≥80 cm/s (vertebral artery) and ≥95 cm/s (basilar artery), all false-positive results were eliminated (specificity and positive predictive value, 100%). Conclusions Our data suggest that transcranial Doppler has good specificity for the detection of vertebral artery vasospasm and good sensitivity and specificity for the detection of basilar artery vasospasm. Transcranial Doppler is highly specific (100%) for vertebra] and basilar artery vasospasm when flow velocities are ≥80 and ≥95 cm/s, respectively.

Detection of vasospasm by transcranial Doppler sonography: The challenges of the anterior and posterior cerebral arteries

Little information exists on the utility of transcranial Doppler sonography (TCD) in detecting anterior (ACA) and posterior cerebral artery (PCA) vasospasm following subarachnoid hemorrhage. During the period at risk for vasospasm, 53 patients with subarachnoid hemorrhage who had technically adequate TCD performed within 24 hours of cerebral angiography, allowing evaluation of 87 ACAs and 84 PCAs, were studied. ACA and PCA vasospasm were defined by mean blood flow velocities of at least 120 cm/ sec and at least 90 em/sec, respectively. For detection of ACA vasospasm, sensitivity was 18% and specificity was 65%. For PCA vasospasm, sensitivity was 48% and specificity was 69%. False‐positive findings for occlusion accounted for 12 (92 %) of 13 ACA false‐positive results and 7 (37%) of 19 PCA false‐positive results, and were most often due to anatomical factors and operator error or inexperience. After exclusion of both true‐positive and false‐positive findings for occlusion and changes in the diagnostic criterion to at least 130 cm/sec for ACA vasospasm and at least 110 cm/sec for PCA vasospasm, specificity improved for both types of vasospasms (100 and 93%, respectively). However, the sensitivity of TCD to detect ACA and PCA vasospasm is limited by a variety of anatomical, technical, and other factors. It is concluded that TCD is highly specific in detecting both ACA and PCA vasospasm in arteries that can be insonated.

Histopathology and CT analysis of partially resected middle turbinates.

Thirty‐eight partial middle turbinate resections from 20 patients undergoing endoscopic sinus surgery were evaluated by histopathology of mucosa and bone and by computed tomography (CT) appearance prior to resection. Histopathologic analysis revealed not only mucosal inflammation but also chronic osteitis of the bone in all patients with sinus disease. The preoperative CT was accurate in predicting turbinate osteitis when the scans displayed advanced grades III and IV disease. These findings suggest that in advanced disease, conservative partial middle turbinate resections may be necessary to remove chronically infected bone from the osteomeatal complex. Because it is unsafe to remove all of the middle turbinate, consideration should also be given to long‐term antibiotic therapy to treat the osteitis found in advanced disease.

Stroke in Williams syndrome.

BACKGROUND Williams syndrome is a genetic disorder characterized by a high incidence of heart disease, arterial stenosis, and hypertension. Despite these features, cerebrovascular accidents have been described only recently and only in association with stenoses of the cerebral vasculature. CASE DESCRIPTION A 19-year-old girl with Williams syndrome developed an acute-onset hemiparesis. MRI demonstrated an infarct involving the internal capsule and putamen. No stenotic areas were seen on angiography. CONCLUSIONS Stroke should be considered as a possible consequence of Williams syndrome, even in the absence of stenoses of the cerebral vasculature. Comparison of this case with those previously reported in the literature emphasizes the multiplicity of features in Williams syndrome that can contribute to the risk of stroke.

Accuracy of clinical examination versus computed tomography in detecting occult lymph node involvement in patients with oral epidermoid carcinoma.

PURPOSE To determine the accuracy of clinical examination versus computed tomography (CT) scanning in detecting positive cervical lymph nodes (N) in patients with epidermoid carcinomas of the oral cavity, 27 patients with epidermoid carcinomas were reviewed. PATIENTS AND METHODS The patients underwent 40 neck dissections, 20 with N- and 20 with N+ necks histologically. All patients were examined by the same clinician, and all CT scans were read by the same radiologist. Patients with clinical and CT N- necks underwent neck dissection only if the neck had to be entered to resect the primary tumor or if the primary tumor was T3 or T4 with a high probability of microscopic metastasis. RESULTS Of the 20 necks that were histologically N-, 16 (80%) were clinically diagnosed as N- and 4 (20%) N+ versus 18 (90%) N- and 2 (10%) N+ diagnosed by CT scan. Of the 20 histologically N+ necks, 12 (60%) were clinically diagnosed as N+ and 8 (40%) N- versus 11 (55%) N+ and 9 (45%) N- diagnosed by CT scan. All lymph nodes diagnosed as N- by both clinical examination and CT scan were less than 1 cm in diameter. Overall, clinical examination of the neck was correct in 28 patients (70%) and the CT scan was correct in 29 patients (73%). Both clinical examination and CT scan were more accurate in diagnosis of N- necks. In 31 necks (78%), the CT and clinical examination were in agreement. Of these, 10 of 10 (100%) were correctly positive. Of the 21 in which both were negative, 14 were histologically N-, and 14 (67%) were correct. Overall, in those cases in which both CT and clinical examination were in agreement, the diagnosis was correct in 24 of 31 (77%). CONCLUSION These results suggest that there is no significant difference in the accuracy of clinical examination versus CT scanning in detecting both positive and negative cervical nodes. When both CT and clinical examination agree, positive cervical nodes are almost always correctly diagnosed. However, one third of the negative cervical nodes were incorrectly diagnosed. Improved methods for detecting occult disease are still needed.