Hyperdense middle cerebral artery sign on CT: efficacy in detecting middle cerebral artery thrombosis

The hyperdense middle cerebral artery sign is a CT predictor of the development of a large cerebral infarct. The limits of detectability were tested in a blinded, then unblinded analysis of CT scans from 25 acute stroke patients. In the initial blinded analysis, sign detection exhibited the following mean values: sensitivity, 78.5%; specificity, 93.4%; positive predictive value, 66%; negative predictive value, 96.4%; accuracy, 91.3%. Kappa statistics analysis indicated poor interobserver agreement (k = .38). Results of unblinded analysis were as follows: sensitivity, 69%; specificity, 94.4%; positive predictive value, 82.8%; negative predictive value, 88.7%; accuracy, 87.3%. There was fair unblinded interobserver agreement (k = .53). Unblinded analysis had a lower false-positive frequency and did not increase the number of true-positive determinations. We conclude that detection of the hyperdense middle cerebral artery sign on CT scans by multiple observers is a sensitive, accurate, and predictive indicator of middle cerebral artery thromboembolism.     

Persistent trigeminal artery: Unusual associated abnormalities

Summary Multiple cases of vascular abnormalities associated with the persistent trigeminal artery or a variant thereof are presented. A persistent otic artery variant is the only known such case in the literature     

Enlargement of cerebral third ventricle in psychotic patients with delayed response to neuroleptics

Enlargement of the cerebral third ventricle appears to be a replicable finding in groups of patients with psychotic illnesses, and there is evidence for an association of third ventricle enlargement with poorer response to treatment. Third ventricle area and width were measured from computed tomography (CT) scans in 24 mood-incongruent psychotic patients and 14 controls age and gender matched to schizophrenic patients. Patients were treated with a fixed dose of haloperidol and classified as rapid responders (55% symptom reduction on New Haven Schizophrenic Index (NHSI) within 4.5 +/- 1.3 days) or delayed responders (55% symptom reduction on NHSI within 18.6 +/- 10.5 days). The significant enlargement of third ventricle area was isolated among the 12 delayed neuroleptic responders (19.3 +/- 9.0 mm2) compared with the 14 controls (11.7 +/- 4.8 mm2, p = 0.01), and 12 other mood-incongruent psychotics. Third ventricle width also showed a trend towards larger width in the delayed responders. There was a clear positive correlation between ventricular size and patient's age exclusively in the delayed responders (r = 0.78); a comparable relationship between ventricular size and age was not present in controls, or in the other psychotics. This finding is consistent with an age-related progressive degenerative process in the central nervous system (CNS) isolated to the neuroleptic-delayed responsive psychotics.     

Recurrent laryngeal nerve and voice preservation: routine identification and appropriate assessment �C two important steps in thyroid surgery

INTRODUCTION

The aims of this study were to assess and compare vocal cord functions before and after thyroid surgery after intra-operative identification of recurrent laryngeal nerve.

PATIENTS AND METHODS

Recurrent laryngeal nerve (RLN) is seen intra-operatively in all cases undergoing thyroid surgeries. Vocal cord functions including any voice change were evaluated by indirect laryngoscopy (I/L) and direct laryngoscopy (D/L) before and after surgery.

RESULTS

Prospective study on 100 patients over 18 months with a total of 146 nerves at risk (NAR). Majority were women (n = 86) with mean age of 37.48 years (range, 13–60 years). RLN was seen in all patients and 19 patients complained of some change in quality of their voice after surgery. Evaluation by I/L and D/L at 6 weeks showed recurrent laryngeal nerve palsy (RLNP) in nine (47.36%) and five (26%) of these 19 patients respectively. Analysed according to total NAR, the incidence of voice change and temporary RLN palsy (I/L and D/L) at 6 weeks was still less at 13.01%, 6.16% and 3.42%, respectively. Voice change improved in all cases at 3 months with no RLNP palsy by I/L or D/L. All these 19 patients had undergone difficult or extensive surgery for malignancy, large gland, extratyhroidal spread or fibrosis.

CONCLUSIONS

Despite identification and preservation of RLN, patients can develop postoperative voice change and RLNP although all voice change cannot be attributed to damaged RLN. Proper assessment of vocal cord functions by I/L and D/L laryngoscopy is required to rule out injuries to these nerves. Risk of damage is higher in patients undergoing more difficult surgery.