PubMed Health⌕ Search

Biomedical subjects

W Morrish

Publications and source records attributed to W Morrish.

7 recordsLinked to original sources

Multicenter evaluation of a self-expanding carotid stent system with distal protection in the treatment of carotid stenosis.

PURPOSE: Carotid artery stent placement may be limited by the embolization of atheromatous material. We evaluated the safety and feasibility of the Medtronic Self-Expanding Carotid Stent (Exponent) in combination with the Medtronic Interceptor Carotid Filter System for the treatment of carotid stenosis among patients at high risk for carotid endarterectomy. METHODS: Patients at high risk for carotid endarterectomy but amenable to percutaneous treatment with stent placement were enrolled. Clinical follow-up was performed at 30 days and 6 and 12 months postprocedure. The National Institutes of Health Stroke Scale was assessed before and within 3 days postprocedure and at 30 days and 6 months postprocedure. Angiography was performed pre- and postprocedure, and carotid duplex scans were performed at baseline and at 30 days and 6 months. RESULTS: Fifty-two carotid procedures were performed in 51 patients (mean age, 69 years; 84% of patients were men). The major adverse event (MAE) rate (death, stroke, and myocardial infarction [MI]) at 30 days was 5.9%: 2 strokes and a single death from periprocedural MI. MAE rates after 6 and 12 months were 5.9% and 11.8%, respectively. The delivery success rate was 94.2% (49/52) for the Interceptor Filter System and 95.9% (47/49) for the Exponent Stent. The mean diameter stenosis of the target lesion was reduced from 62.4% preprocedure to 21.2% postprocedure. CONCLUSION: High delivery success rates were achieved with a low rate of MAE (death, stroke, or MI) in a high-risk population. Treatment of carotid artery disease with the Exponent Carotid Stent combined with distal protection from the Interceptor Filter System is effective and safe.

Aged↗

Intra-arterial thrombolysis for retinal artery occlusion: the Calgary experience.

INTRODUCTION: Retinal artery occlusion represents a medical emergency with poor prognosis for visual recovery. Spontaneous improvement is estimated to occur in less than 15% of central retinal artery occlusion (CRAO) cases and conventional treatments have provided only limited benefit. Intra-arterial thrombolysis has been reported as a potentially efficacious and safe treatment. METHODS: We performed a retrospective chart review of all retinal artery occlusion cases treated with intra-arterial recombinant tissue-type plasminogen activator (rtPA) from January 1998 to May 2004. Patients received Goldmann perimetry visual field testing at a variable interval following the procedure (2 days-2.5 years). Visual acuity (VA) was re-assessed in May 2004. RESULTS: Eight cases (59-77 years) were treated for CRAO, 6-18 hours post-onset with intra-arterial rtPA (10-20 mg over 15-60 minutes); one case of branch occlusion (BRAO) was treated with 30 mg rtPA over 75 minutes, 12 hours post-onset. Among the six patients with CRAO assessed in clinic, three experienced improvement in VA by two or more gradations (Snellen lines); three improved by one gradation. However, none achieved a final VA better than 20/300. The case of branch occlusion improved to a VA of 20/20. All patients had residual monocular field defects. CONCLUSIONS: Our findings reveal a limited benefit for intra-arterial tPA compared to the rate of spontaneous improvement and conventional forms of therapy for retinal artery occlusion.

Adult↗

Magnetic resonance diffusion weighted imaging in cerebral fat embolism.

The use of diffusion weighted imaging with apparent diffusion coefficient mapping in the diagnosis of cerebral fat embolism is shown here to demonstrate infarcts secondary to fat emboli more intensely than T2 weighted sequences 24 hours after the onset of symptoms. Embolic foci are hypointense on apparent diffusion coefficient mapping consistent with cytotoxic edema associated with cell death and restricted water diffusion. This technique increases the sensitivity for detecting cerebral fat embolism and offers a potentially important tool in its diagnosis.

Adult↗

Mild head injury: a misnomer.

Despite controversy surrounding the concept of mild head injury (MHI), it is becoming evident that even a head trauma termed 'mild' may result in significant behavioural sequelae. The present study was an attempt at documenting structural cerebral damage, by way of computerized tomography, in a group of patients having suffered a MHI as defined by the Glasgow Coma Scale (GCS) score. A 1-year retrospective chart review identified 80 MHI patients who presented to the Emergency department of a lead hospital for trauma. Sixty-six per cent of these MHI patients were scanned. Evidence of intracranial abnormalities was obtained in 31% of the overall sample. Patients with a lower GCS score had a higher percentage of abnormal scans than those with a GCS score of either 14 or 15. The present findings suggest that a MHI can be associated with significant morbidity, and that a MHI group does not constitute a homogeneous pool of patients.

Adult↗

Intracranial hemorrhage after stenting and angioplasty of extracranial carotid stenosis.

BACKGROUND AND PURPOSE: The transluminal angioplasty and stenting procedure has been recently advocated as a potential alternative to surgical endarterectomy for the treatment of severe extracranial carotid stenosis. This study assesses the incidence and significance of intracranial hemorrhage occurring after this procedure. METHODS: We retrospectively reviewed 104 carotid arteries (96 internal, two external, and six common) in 90 patients (63 male; mean age, 69.4 years; range, 48-88 years) who underwent primary stenting and angioplasty by use of Wallstents (103/104) at three centers between January 1996 and January 1999. Seventy-five (83%) patients were referred by neurosurgery departments. Seventy-one (68%) arteries were symptomatic; the mean stenosis percentage was 85% (range, 40-99%). RESULTS: Four intraparenchymal hemorrhages occurred, representing 4.4% of patients and 3.8% of vessels, after angioplasty and stent placement. The mean preoperative stenosis percentage was 95% (range, 90-99%). One hemorrhage occurred immediately after stent placement, whereas the three other hemorrhages occurred in a delayed fashion (mean, 2.8 days). The mean hematoma size was 4.8 cm (range, 2-8 cm). Three patients had associated subarachnoid or intraventricular bleeding; the fourth had associated subdural hemorrhage. Three hemorrhages were fatal; the fourth experienced two seizures only. No acute neurologic symptoms were present prior to hemorrhages, and there was no postprocedural hypertension in these patients. All had been receiving antiplatelet agents as well as intraprocedural IV heparin. CONCLUSION: Intracranial hemorrhage can occur after carotid angioplasty and stenting. We speculate that this represents cerebral hyperperfusion injury. The 3.8% incidence of cerebral hemorrhage observed is approximately sixfold greater than that reported post endarterectomy (0.6%) (95% CI, 0.2-8.7%). This is not statistically significant in this small study group. This trend may reflect patient selection, different anticoagulation protocols, and/or study population size. Additional data are needed to determine the safety and efficiency of carotid stenting as a treatment for carotid stenosis.

Aged↗