Winfield S. Fisher

Elective Stenting of the Extracranial Carotid Arteries

OBJECTIVES In symptomatic and asymptomatic patients with significant carotid artery stenosis, surgical endarterectomy has been shown to be beneficial when compared with medical management. Carotid stenting is evolving as an alternative technique for treating such patients. This prospective study was designed to assess the feasibility and safety of carotid angioplasty and stenting. METHODS Fourteen patients (15 carotid arteries) with significant carotid artery stenosis were enrolled. These patients were in the age range 46 to 84 years (mean 60.9 +/- 7 years) and there were 12 males (86%). All of these patients were symptomatic with either TIA (n = 8) or stroke (n = 6). Wallstents were used in all the cases to stent the carotid arteries. One patient underwent bilateral carotid artery stenting. RESULTS Carotid angioplasty and stenting was successful in 13 out of 14 (92.8%) patients and 14 out of 15 (93.3%) carotid arteries, with reduction in mean (+/- SD) stenosis from 86 +/- 6% to 3 +/- 3%. There was one episode of minor stroke, no major stroke or death during the initial hospitalization. Another patient had a minor stroke with patent ipsilateral carotid artery (on repeat angiography) during the first 30 days after the procedure. This patient was also found to have asymptomatic thrombus formation in the contralateral carotid stent which resolved with intravenous anticoagulation. During a mean follow up of 6 +/- 2 months there has been no recurrence of symptoms. CONCLUSIONS Based upon our limited experience we believe that percutaneous carotid angioplasty with stenting is feasible with low periprocedural complication rate.

Microemboli detected by transcranial Doppler monitoring in patients during carotid angioplasty versus carotid endarterectomy.

UNLABELLED Microemboli, as detected by transcranial Doppler monitoring, have been shown to be a potential cause of strokes after carotid endarterectomy. We retrospectively reviewed 105 patients who underwent transcranial Doppler monitoring during 112 procedures for the treatment of 115 carotid bifurcation stenoses: 40 by percutaneous angioplasty with stenting and 75 by carotid endarterectomy. In PTAS procedures (n = 40), there was a mean of 74.0 emboli per stenosis (range 0-398, P = 0.0001) with 4 neurologic events per patient (P = 0.08). In CEA procedures (n = 76), there was a mean of 8.8. emboli per stenosis (range 0-102, P= 0.0001) with 1 neurologic event per patient (P = 0.08). The post-procedural neurological events in the percutaneous angioplasty with stenting population included two strokes (5.6%) and two transient ischemia attacks (5.6%). Microemboli for each of these cases totalled 133, 17, 29 and 47 (with one shower), respectively. One postoperative carotid endarterectomy patient was noted to have a stroke (1.4%), with 48 microemboli noted during that procedure. The mean emboli rate for percutaneous angioplasty with stenting patients with neurological events was 59.0: without complications it was 85.1. The mean emboli rate for carotid endarterectomy patients without complications was 8.3. Three percutaneous angioplasty with stenting patients had no emboli (7.5%), whereas 29 carotid endarterectomy patients had no emboli (38.7%). CONCLUSION The percutaneous angioplasty with stenting procedure is associated with more than eight times the rate of microemboli seen during carotid endarterectomy when evaluated with transcranial Doppler monitoring. Larger patient groups are needed to determine if this greater embolization rate has an associated risk of higher morbidity or mortality.

Hitting a moving target: evolution of a treatment paradigm for atypical meningiomas amid changing diagnostic criteria

OBJECT The World Health Organization (WHO) reclassified atypical meningiomas in 2000, creating a more clear and broadly accepted definition. In this paper, the authors evaluated the pathological and clinical transition period for atypical meningiomas according to the implementation of the new WHO grading system at their institution. METHODS A total of 471 meningiomas occurring in 440 patients between 1994 and 2006 were retrospectively reviewed to determine changes in diagnostic rates, postoperative treatment trends, and early outcomes. RESULTS Between 1994 and 2000, the incidence of the atypical meningiomas ranged from 0 to 3/year, or 4.4% of the meningiomas detected during the entire period. After 2002, the annual percentage of atypical meningiomas rose over a 2-year period, leveling off at between 32.7 and 35.5% between 2004 and 2006. The authors also found a recent trend toward increased use of adjuvant radiation therapy for incompletely resected atypical meningiomas. Prior to 2003, 18.7% were treated with this therapy; after 2003, 34.4% of lesions received this treatment. Incompletely resected tumors were treated with some form of radiation 76% of the time. In cases of complete resection, most patients were not given adjuvant therapy but were expectantly managed by close monitoring using serial imaging and by receiving immediate treatment for tumor recurrence. The overall recurrence rate for expectantly managed tumors was 9% over 28.2 months, and 75% of recurrences responded to delayed radiation therapy. CONCLUSIONS The authors documented a significant change in the proportion of meningiomas designated as atypical during a transition period from 2002 to 2004, and propose a conservative strategy for the use of radiation therapy in atypical meningiomas.

A comparison of carotid angioplasty with stenting versus endarterectomy with regional anesthesia

Abstract Introduction: Percutaneous transluminal angioplasty with stenting (PTAS) has been considered a potential alternative to carotid endarterectomy (CEA) for stroke prevention. Interventionalists have suggested that PTAS carries less anesthetic risk than CEA. The treatment of carotid stenosis with local or regional anesthesia (LRA) allows direct intraprocedural neurologic evaluation and avoids the potential risks of general anesthesia. Methods: We retrospectively analyzed the clinical charts of 377 patients who underwent 414 procedures for the elective treatment of carotid stenosis in 433 cerebral hemispheres with LRA between August 1994 and May 1997. Group I (312 hemispheres) underwent PTAS, and group II (121 hemispheres) underwent CEA. Results: The indications for treatment included the following: asymptomatic severe stenosis (n = 272; 62.8%), transient ischemic attack (TIA; n = 100; 23.1%), and prior stroke (n = 61; 14.1%). The early neurologic results for the patients in group I (n = 268) included 11 TIAs (4.1%), 23 strokes (8.6%), and 3 deaths (1.1%). The early neurologic results for the patients in group II (n = 109) included 2 TIAs (1.8%), one stroke (0.9%), and no deaths. The total stroke and death rates were 9.7% for the patients in group I and 0.9% for the patients in group II (P = .0015). The cardiopulmonary events that led to additional monitoring were evident after 96 procedures in group I (32.8%) and 21 procedures in group II (17.4%; P = .002). Conclusion: PTAS carries a higher neurologic risk and requires more monitoring than CEA in the treatment of patients with carotid artery stenosis with LRA. The proposed benefit for the use of PTAS to avoid general anesthesia cannot be justified when compared with CEA performed with LRA. (J Vasc Surg 1998;28:397-403.)

Hypertonic saline for treating raised intracranial pressure: literature review with meta-analysis

OBJECT Currently, mannitol is the recommended first choice for a hyperosmolar agent for use in patients with elevated intracranial pressure (ICP). Some authors have argued that hypertonic saline (HTS) might be a more effective agent; however, there is no consensus as to appropriate indications for use, the best concentration, and the best method of delivery. To answer these questions better, the authors performed a review of the literature regarding the use of HTS for ICP reduction. METHODS A PubMed search was performed to locate all papers pertaining to HTS use. This search was then narrowed to locate only those clinical studies relating to the use of HTS for ICP reduction. RESULTS A total of 36 articles were selected for review. Ten were prospective randomized controlled trials (RCTs), 1 was prospective and nonrandomized, 15 were prospective observational trials, and 10 were retrospective trials. The authors did not distinguish between retrospective observational studies and retrospective comparison trials. Prospective studies were considered observational if the effects of a treatment were evaluated over time but not compared with another treatment. CONCLUSIONS The available data are limited by low patient numbers, limited RCTs, and inconsistent methods between studies. However, a greater part of the data suggest that HTS given as either a bolus or continuous infusion can be more effective than mannitol in reducing episodes of elevated ICP. A meta-analysis of 8 prospective RCTs showed a higher rate of treatment failure or insufficiency with mannitol or normal saline versus HTS.

Short-term antifibrinolytic therapy before early aneurysm treatment in subarachnoid hemorrhage: effects on rehemorrhage, cerebral ischemia, and hydrocephalus.

BACKGROUND:Long-term administration of the antifibrinolytic agent epsilon aminocaproic acid (EACA) reduces the rate of rehemorrhage in patients with aneurysmal subarachnoid hemorrhage (SAH), but is associated with cerebral ischemia. OBJECTIVE:To evaluate short-term administration of EACA before early surgery in patients with SAH. METHODS:Retrospective review of 356 patients admitted between June 2002 and December 2007 with a diagnosis of aneurysmal SAH. Medical records were reviewed to determine SAH risk factors, clinical grade at the time of admission, and incidence of rehemorrhage, permanent new-onset focal neurological deficits, computed tomography evidence of cerebral infarction, symptomatic vasospasm, and hydrocephalus. RESULTS:Patients underwent treatment of the ruptured aneurysm an average of 47.4 hours after admission and received an average total dose of 40.6 g of EACA. The mean length of time of administration of EACA was 35.6 hours. There was a total of 5 rehemorrhages, for an overall rebleeding rate of 1.4% and a rate of rehemorrhage per 24-hour period of 0.71%. Overall, the rates of symptomatic vasospasm and permanent neurological deficits attributable to ischemic stroke were 11.5% and 7.2%, respectively, and the incidence of shunt-dependent hydrocephalus was 42.3%. Patients who were treated with coiling had higher rates of symptomatic vasospasm and ischemic complications than patients who had surgery. CONCLUSION:Short-term administration of EACA is associated with rates of rehemorrhage, ischemic stroke, and symptomatic vasospasm that compare favorably with historical controls. The rate of hydrocephalus is relatively high and may be attributable to EACA treatment.

Vein of Galen aneurysmal malformations: critical analysis of the literature with proposal of a new classification system

Vein of Galen aneurysmal malformations are a rare and diverse group of entities with a complex anatomy, pathophysiology, and serious clinical sequelae. Due to their complexity, there is no uniform treatment paradigm. Furthermore, treatment itself entails the risk of serious complication. Offering the best treatment option is dependent on an understanding of the aberrant anatomy and pathophysiology of these entities, and tailored therapy is recommended. Herein, the authors review the current concepts related to vein of Galen aneurysmal malformations and suggest a new classification system excluding mesodiencephalic plexiform intrinsic arteriovenous malformations from this group of malformations.

Antifibrinolytic therapy in aneurysmal subarachnoid hemorrhage increases the risk for deep venous thrombosis: A case–control study

OBJECTIVES Aneurysm re-rupture is associated with significant morbidity and mortality in aneurysmal subarachnoid hemorrhage (aSAH). While antifibrinolytics reduce aneurysm re-rupture rates, they have been associated with hydrocephalus, delayed cerebral ischemia, and venous thrombosis. We performed a case-control study in patients enrolled in the Cerebral Aneurysm Renin Angiotensin System (CARAS) study to evaluate the impact of short course (<48 h) ɛ-aminocaproic acid (EACA) on deep venous thrombosis (DVT) rates. PATIENTS AND METHODS A case-control study design was utilized to evaluate the effect of EACA on DVT formation. All cases and controls were obtained from the CARAS study, a prospective, blinded study assessing the association of polymorphisms in the renin angiotensin system and aSAH. RESULTS One hundred and twenty-eight eligible patients were enrolled in CARAS. Overall, 48 (37.5%) patients were screened for DVT, 57 (44.5%) patients were treated with short course (<48 h) EACA, and 8 (6.3%) patients suffered a re-rupture (4 treated with EACA). Ten patients (7.8%) were diagnosed with DVT as evidenced by Doppler US and represent the cases. Twenty controls without evidence of a DVT matched for age, sex, race, tobacco history, Hunt-Hess score, Fisher grade, body mass index, and length of stay were identified from the remaining pool of 118 patients. EACA was found to significantly increase the risk of DVT formation in patients with aSAH (OR 8.49, CI 1.27-77.1). CONCLUSION Short course (<48 h) administration of EACA in patients with aneurysmal subarachnoid hemorrhage is associated with an 8.5 times greater risk of DVT formation.

Arterial supply of the lower cranial nerves: A comprehensive review

The lower cranial nerves receive their arterial supply from an intricate network of tributaries derived from the external carotid, internal carotid, and vertebrobasilar territories. A contemporary, comprehensive literature review of the vascular supply of the lower cranial nerves was performed. The vascular supply to the trigeminal, facial, vestibulocochlear, glossopharyngeal, vagus, spinal accessory, and hypoglossal nerves are illustrated with a special emphasis on clinical issues. Frequently the external carotid, internal carotid, and vertebrobasilar territories all contribute to the vascular supply of an individual cranial nerve along its course. Understanding of the vasculature of the lower cranial nerves is of great relevance for skull base surgery. Clin. Anat. 27:108–117, 2014.

Association of nosocomial infections with delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage

OBJECTIVE Delayed cerebral ischemia (DCI) is a recognized complication of aneurysmal subarachnoid hemorrhage (aSAH) that contributes to poor outcome. This study seeks to determine the effect of nosocomial infection on the incidence of DCI and patient outcome. METHODS An exploratory analysis was performed on 156 patients with aSAH enrolled in the Cerebral Aneurysm Renin Angiotensin System study. Clinical and radiographic data were analyzed with univariate analysis to detect risk factors for the development of DCI and poor outcome. Multivariate logistic regression was performed to identify independent predictors of DCI. RESULTS One hundred fifty-three patients with aSAH were included. DCI was identified in 32 patients (20.9%). Nosocomial infection (odds ratio [OR] 3.5, 95% confidence interval [CI] 1.09-11.2, p = 0.04), ventriculitis (OR 25.3, 95% CI 1.39-458.7, p = 0.03), aneurysm re-rupture (OR 7.55, 95% CI 1.02-55.7, p = 0.05), and clinical vasospasm (OR 43.4, 95% CI 13.1-143.4, p < 0.01) were independently associated with the development of DCI. Diagnosis of nosocomial infection preceded the diagnosis of DCI in 15 (71.4%) of 21 patients. Patients diagnosed with nosocomial infection experienced significantly worse outcomes as measured by the modified Rankin Scale score at discharge and 1 year (p < 0.01 and p = 0.03, respectively). CONCLUSIONS Nosocomial infection is independently associated with DCI. This association is hypothesized to be partly causative through the exacerbation of systemic inflammation leading to thrombosis and subsequent ischemia.