Peter J. Barbour

Internal carotid artery redundancy is significantly associated with dissection.

Background and Purpose Redundant internal carotid arteries have been considered a risk factor in tonsillectomy, adenoidectomy, and surgical treatment of peritonsillar abscess and also a potentially treatable cause of stroke. However, an association between internal carotid artery redundancy and spontaneous dissection has not yet been clearly demonstrated. Methods We reviewed, for spontaneous carotid artery dissection, records of all patients admitted to our institution during the period from 1986 through 1992 with the diagnosis of stroke or transient ischemic attack. We also reviewed 108 percutaneous cerebral arteriograms performed between September 1992 and December 1992 for presence of carotid artery redundancies. Results Thirteen patients exhibited spontaneous dissection. Of these, 8 of 13 (62%) patients and 13 of 20 (65%) internal carotid arteries, viewed to the siphon, had significant redundancies, kinks, coils, or loops. Of 108 consecutive arteriograms of patients without dissection, in which 187 internal carotid arteries were viewed to the siphon, there were 20 (19%) patients and 22 (12%) of 187 vessels with significant redundancy. Five patients in the dissection group and 2 in the nondissection group had bilateral internal carotid artery redundancy (P=.0019 and P=.0001, respectively). Conclusions We found a significant correlation between internal carotid artery redundancy and dissection, particularly if redundancy is present bilaterally.

Spectrum and Potential Pathogenesis of Reversible Posterior Leukoencephalopathy Syndrome

BACKGROUND Controversy still exists over the etiology and pathophysiology of reversible posterior leukoencephalopathy syndrome (RPLS). This large single-center case series aims to describe the clinical and imaging features of RPLS in an attempt to deduce the etiology of the disorder and the mechanisms of brain injury. METHODS A retrospective chart and imaging review was conducted on 59 cases of RPLS in 55 patients. RESULTS Five RPLS imaging patterns were observed: posterior predominant (n = 40), anterior predominant (n = 7), diffuse lesion (n = 7), basal ganglia predominant (n = 3), and brainstem/cerebellum predominant patterns (n = 2). RPLS resulted in permanent neurologic deficits in 14 patients and death in 4 patients. Hypertension was seen in 57 (97%) cases, and mean arterial blood pressure exceeded 140 mm Hg in 30 (51%) cases. Follow-up magnetic resonance imaging scans revealed a significant worsening of vasogenic edema in 2 cases, both with persistent hypertension. Magnetic resonance imaging scans revealed areas of ischemia in 14 cases, all within or at areas closely adjacent to vasogenic edema. Diffuse vasculopathy was seen in 8 cases. There was a lack of correlation between the presence of vasculopathy and the degree of vasogenic edema (P = .62), but a correlation was suggested between ischemia and vasculopathy (P = .02). CONCLUSIONS This study strongly suggests that hypertension-induced vasodilation rather than vasoconstriction-mediated hypoxia is likely the major mechanism responsible for the development of vasogenic edema, and that vasoconstriction may contribute to the development of ischemia in RPLS.

Hemiplegic migraine during pregnancy : Unusual magnetic resonance appearance with SPECT scan correlation

Objective.—This article discusses the pathophysiology and implications for treatment of hemiplegic migraine within a case study presentation.

Development of a novel EEG rating scale for head injury using dichotomous variables

We developed a new EEG rating scale for electrographic assessment of head injured patients. Phenomena present in posttraumatic EEG were scored as dichotomous variables (present or absent). These phenomena included background activity (alpha, beta, theta, delta), sleep spindles, focal abnormalities, reactivity and variability, epileptiform activity, and specific comatose patterns. Each variable was weighted according to its perceived prognostic value: i.e., normal alpha 10, flat EEG -10, spindles 4, etc. Combinations of possible scores ranged from +23 to -10. Fifty-seven EEGs from different head injured patients were independently and retrospectively analyzed by two investigators. There was a high correlation for intra- (r = 0.95) and inter- (r = 0.85) observer rating using the dichotomous test. When patients with scores over 15 (i.e., with reactive alpha) and patients with scores of -10 (i.e., ECI records) were excluded, the intra-rater and inter-rater correlations were still high (0.81 and 0.76, respectively). There was a high correlation between Glasgow outcome score at discharge and the dichotomous EEG score. This EEG scale scores most major categories of EEG activity, utilizes a multipoint scale for correlation purposes, and allows data to be analyzed in sub-categories (i.e., spindles in coma). The separate weighting score allows for refinement of the scale after data collection (i.e., to fit prospective outcome). We feel that this scale is reproducible and valid, and may be applicable to other patient groups with severely altered EEGs.

Outcome of severe brain injury: a multimodality neurophysiologic study.

We screened all head-injured trauma patients admitted to Lehigh Valley Hospital during a 2-year period. From 725 screened patients, 69 patients in a coma on the second day after trauma were entered into this study. During the first week, these patients underwent electroencephalography (EEG), evoked potentials, ocular pneumoplethysmography, and transcranial Doppler (TCD) sonography. Clinical examinations were undertaken 2 and 7 days after trauma. Test results were correlated with functional clinical outcome at 6 months. In a multiple regression analysis, EEG was the major independent variable that significantly predicted 6-month outcome based on Glasgow Outcome Scale score. Transcranial Doppler sonography contributed a small additional component. Though EEG was the most significant predictive factor in this neurophysiological battery, it did not add significantly to the predictive power of Glasgow Coma Scale score determined at day 7. These findings suggest that in neurophysiologic testing in this type of patient is not useful in improving predictive outcome data.

Episodic low-amplitude events: an under-recognized phenomenon in clinical electroencephalography.

In a series of 20 EEGs from 15 patients, well-defined brief attenuations occurred interspersed among the background activity. These episodic low-amplitude events (ELAEs) typically lasted 0.5-4 s. They were hemispheric or bisynchronous and occurred in patients with coma of various etiologies, including status epilepticus. The episodes of attenuation were brief and no bursts of activity were present, distinguishing this finding from burst-suppression. Prognosis was poor in the patients with coma due to entities other than status epilepticus. In the setting of status epilepticus, the prognosis depended on the etiology. This pattern may be an ictal phenomenon, or a product of waveform simplification. ELAEs are a manifestation of seriously abnormal EEG activity and correlate with a 50% mortality.

Alzheimer's disease in Down's syndrome with SPECT.

Alzheimers disease often occurs in patients with Downs syndrome. SPECT scanning with I-123 IMP and Tc-99m HMPAO identifies decreased cerebral perfusion and metabolism in these patients at lower cost. In this case, SPECT scanning revealed changes in Alzheimers disease in a Downs syndrome patient.

Telehealth for patients with Parkinson’s disease: delivering efficient and sustainable long-term care

ABSTRACT Objectives: We set out to demonstrate the benefits of providing long-term care via telehealth for patients with Parkinson’s disease living in continuous care facilities. Methods: A cohort of 16 patients with Parkinson’s disease residing at one of 2 locations of a multi-facility continuous care retirement organization were seen virtually in follow-up over a 3-year period by Telehealth Services at a large, academic, tertiary care hospital in southeastern Pennsylvania. The data collected during that period, studied retrospectively, included demographic information, number of telehealth visits, and UPDRS scores obtained at each visit. Satisfaction and potential cost savings were also reviewed. Results: UPDRS scores declined over the period of observation, from a range of 18-60 at study start to 28-72 at study end. Actual cost savings are difficult to define; however, the cost per telehealth visit at

Episodic Low Amplitude Events.

117.30 was often lower than the facility’s average cost for transporting patients to a visit in the neurologist’s office. Patients, families, subspecialists, and the nursing staff expressed uniformly high satisfaction with telehealth. Conclusion: This model for providing care proved to be sustainable and efficient, and promoted collaboration among the providers at the long-term care facility and those at the remote site. These benefits may be applicable to patients with degenerative disorders in similar settings.

A private practice model for teaching and research activities

ABSTRACT.In a series of 27 electroencephalograms from 22 patients, well-defined brief attenuations occurred interspersed among the background activity. These “episodic low amplitude events” (ELAEs) typically lasted 0.5–4 seconds. They were hemispheric or bisynchronous and occurred in patients with coma of various etiologies, including status epilepticus. The episodes of attenuation were brief and no bursts of activity were present, distinguishing this finding from burst-suppression. In the patients with coma other than status epilepticus, prognosis was poor. In the setting of status epilepticus, the prognosis depended on the etiology of status. ELAEs are a manifestation of seriously abnormal electroencephalographic activity and correlate with α 45% mortality.