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Biomedical subjects

M B Horowitz

Publications and source records attributed to M B Horowitz.

At least 19 recordsLinked to original sources
PubMed2007

Pretreatment ipsilateral regional cortical blood flow influences vessel recanalization in intra-arterial thrombolysis for MCA occlusion.

BACKGROUND AND PURPOSE: The aim of acute stroke interventions is to achieve recanalization of the target occluded artery. We sought to determine whether pretreatment cortical cerebral blood flow (CBF) was associated with vessel recanalization in patients undergoing intra-arterial therapy. METHODS: This is a retrospective analysis of patients who underwent a quantitative xenon CT blood flow study and were noted to have a documented M1 middle cerebral artery (MCA) or carotid terminus occlusion less than 6 hours from symptom onset between January 1997 and April 2001. Twenty-three patients who underwent intra-arterial thrombolysis were included in the analysis. Univariate and multivariate analyses were performed to determine whether pretherapy CBF was correlated to the likelihood of recanalization. RESULTS: A total of 23 patients were studied in this analysis with a median age of 69 (range 32-81) and median National Institutes of Health Stroke Score of 19 (range, 8-22). Twelve patients (52%) underwent combined intravenous/intra-arterial therapy, and 11 patients (48%) were treated with intra-arterial thrombolytics alone. Successful vessel recanalization (Thrombolysis in Myocardial Infarction classification 2 or 3 flow) occurred in 13 patients (57%). The only variable associated with recanalization in multivariate modeling was mean ipsilateral MCA CBF (odds ratio, 1.25; 95% confidence interval, 1.01-1.54; P = .035). A receiver operating characteristic curve was generated, and a mean ipsilateral MCA CBF threshold of 18 mL/100 g/min was found to be the threshold for successful recanalization. CONCLUSIONS: Our study suggests that patients with higher mean ipsilateral MCA CBF are more likely to recanalize. The threshold for successful revascularization may be 18 mL/100 g/min. Further study is required to determine whether pretreatment CBF is related to recanalization success.

Adult↗
PubMed2007

Stenting and angioplasty of the symptomatic chronically occluded carotid artery.

Patients with hemodynamic impairment ipsilateral to a carotid occlusion are at a high risk of subsequent stroke, and currently 2 surgical options have been studied: extracranial-to-intracranial bypass and direct thromboendarterectomy. We report the successful revascularization of 2 symptomatic chronically occluded carotid arteries with stenting and angioplasty.

Aged↗
PubMed2006

Urgent stenting of the M2 (superior) division of the middle cerebral artery after systemic thrombolysis in acute stroke.

We report a case of a 54-year-old man who presented with a right middle cerebral artery territory infarct and was treated with systemic thrombolytics. He continued to fluctuate neurologically and, with the use of angiography, was found to have an occlusion of the right M2 artery (superior division). This occlusion was successfully revascularized with a coronary stent.

Acute Disease↗
PubMed2005

A failure to communicate: patients with cerebral aneurysms and vascular neurosurgeons.

OBJECTIVE: To assess communication between vascular neurosurgeons and their patients with unruptured cerebral aneurysms about treatment options and expected outcomes. METHODS: Vascular neurosurgeons and their patients with cerebral aneurysms were surveyed immediately following outpatient appointments in a neurosurgery clinic. Data collected included how well the patient understood their aneurysm treatment options, the risks of a poor outcome from various treatments, and the consensus "best" treatment. Patient and neurosurgeon responses were measured using Likert scales, multiple choice questions, and visual analogue scales. Agreement between patient and neurosurgeon was assessed with kappa scores. The Wilcoxon sign rank test was used to compare visual analogue scale responses. RESULTS: Data for 44 patient-neurosurgeon pairs were collected. Only 61% of patient-neurosurgeon pairs agreed on the best treatment plan for the patient's aneurysm (kappa = 0.51, moderate agreement). Among the neurosurgeons, agreement with their patients ranged from 82% (kappa = 0.77, almost perfect agreement) to 52% (kappa = 0.37, fair agreement). Patients estimated much higher risks of stroke or death from surgical clipping, endovascular embolisation, or no intervention compared with the estimates offered by their neurosurgeons (surgical clipping: patient 36% v neurosurgeon 13%, p<0.001; endovascular embolisation: patient 35% v neurosurgeon 19%, p = 0.040; and no INTERVENTION: patient 63% v neurosurgeon 25%, p<0.001). CONCLUSIONS: Following consultation with a vascular neurosurgeon, many patients with cerebral aneurysms have an inaccurate understanding of their aneurysm treatment plan and an exaggerated sense of the risks of aneurysmal disease and treatment.

Adult↗
PubMed2003

Aneurysm rupture during endovascular coiling: effects on cerebral transit time and neurophysiologic monitoring and the benefits of early ventriculostomy: case report.

OBJECTIVE AND IMPORTANCE: We report a case of intra-operative aneurysm rupture during endovascular therapy and document the effects of rupture on cerebral transit times and neurophysiologic monitoring. The effects of early ventriculostomy are clearly documented. CLINICAL PRESENTATION: A 42-year-old man with Hunt and Hess grade 1, Fisher grade 3 subarachnoid hemorrhage secondary to a 5 mm anterior communicating artery aneurysm underwent coil embolization. INTERVENTION: Endovascular therapy was complicated by intraprocedural aneurysm rupture. Changes in cerebral transit time and electroencephalography along with somatosensory evoked potentials were documented as were improvement in these parameters following aneurysm obliteration and ventriculostomy placement. The patient awoke without deficit and was discharged 2 weeks later with a grossly normal examination. CONCLUSION: Early recognition of aneurysm rupture during coil embolization and prompt aneurysm obliteration and reduction in intracranial hypertension can lead to acceptable patient outcomes. Use of neurophysiologic monitoring in the intubated patient can help the neurosurgeon determine the need for cerebrospinal fluid drainage in such situations.

Adult↗
PubMed2001

Transluminal stent-assisted coil embolization of a vertebral confluence aneurysm: technique report.

BACKGROUND: Recent advances in stent technology have allowed for negotiation of often tortuous posterior circulation intracranial vasculature. Stent-assisted coil embolization is a novel treatment for complex wide-necked aneurysms, as stents provide a buttress that allows for coil deposition while preventing coil herniation into the parent vessel lumen. We describe a case of stent-assisted coil embolization of a complex wide-necked vertebral confluence aneurysm. CASE DESCRIPTION: A 61-year-old woman presented with a Hunt-Hess III, Fisher Grade III subarachnoid hemorrhage secondary to a ruptured vertebral confluence aneurysm demonstrated on angiography. The patient underwent emergent angiography and attempted coiling of a vertebral confluence aneurysm. Because of the aneurysm's complex wide neck and the presence of subclavian steal syndrome, the coils repeatedly herniated into the left vertebral and basilar artery lumina. A flexible coronary stent was deployed across the aneurysm neck, preventing coil herniation and allowing for greater coil deposition. The patient tolerated the procedure and underwent repeat coiling 2 months postoperatively because of mild coil compaction. This resulted in 100% occlusion and the patient is neurologically normal except for a sixth nerve palsy which had been present after the hemorrhage. CONCLUSION: Recent advances in stent technology allow negotiation of the tortuous posterior circulation vasculature. Stent-assisted coil embolization of complex, wide-necked vertebral confluence aneurysms may be an alternative intervention for these surgically challenging lesions.

Aneurysm↗
PubMed2001

Transluminal stent-assisted angiplasty of the intracranial vertebrobasilar system for medically refractory, posterior circulation ischemia: early results.

OBJECTIVE: Symptomatic vertebrobasilar artery stenosis portends a poor prognosis, even with medical therapy. Surgical intervention is associated with considerable morbidity, and percutaneous angioplasty alone has demonstrated mixed results, with significant complications. Recent advances in stent technology have allowed for a novel treatment of symptomatic, medically refractory, vertebrobasilar artery stenosis. We report on a series of patients with medically refractory, posterior circulation stenosis who were treated with transluminal angioplasty and stenting at two medical centers in the United States. METHODS: A retrospective analysis of data for 11 consecutive patients with symptomatic, medically refractory, intracranial, vertebral or basilar artery stenosis was performed. All patients were treated with percutaneous transluminal angioplasty and stenting. Short-term clinical and angiographic follow-up data were obtained. RESULTS: Among 11 patients who were treated with stent-assisted angioplasty of the basilar or vertebral arteries, there were three periprocedural deaths and one delayed death after a pontine stroke. Other complications included a second pontine infarction, with subsequent residual diplopia. The remaining seven patients (64%) experienced symptom resolution and have resumed their preprocedural activities of daily living. Angiographic follow-up examinations demonstrated good patency of the stented lesions for five of seven survivors (71%); one patient exhibited minimal intrastent intimal hyperplasia, and another patient developed new stenosis proximal to the stent and also developed an aneurysm within the stented portion of the basilar artery. The last patient exhibited 40% narrowing of the treated portion of the vessel lumen. CONCLUSION: Recent advances in stent technology allow negotiation of the proximal posterior circulation vasculature. Although the treatment of vertebrobasilar artery stenosis with angioplasty and stenting is promising, long-term angiographic and clinical follow-up monitoring of a larger patient population is needed.

Adult↗
PubMed2001

Rupture of intracranial aneurysms during endovascular coiling: management and outcomes.

OBJECTIVE: In this study, the incidence, etiologies, and management with respect to clinical outcome of patients with iatrogenic aneurysmal rupture during attempted coil embolization of intracranial aneurysms are reviewed. METHODS: A retrospective analysis was conducted of 274 patients with intracranial aneurysms treated with Guglielmi detachable coils over a 6-year period from 1994 to 2000. Patient medical records were examined for demographic data, aneurysm location, the number of coils deployed preceding and after aneurysmal rupture, the etiology of the rupture, and the clinical status on admission and at the time of discharge. RESULTS: Of 274 patients with intracranial aneurysms treated with coil embolization, six (2%) had an intraprocedural rupture. Of these six, two were women and four were men. The mean age was 67 years (range, 52-85 yr). Mean follow-up time was 8 months (range, 0-25 mo). Aneurysmal rupture resulted from detachment of the last coil in three patients, detachment of the third coil (of four) in one patient, and insertion of the first coil in another patient. In one patient, the aneurysmal rupture was a result of catheter advancement before detachment of the last coil. The Glasgow Outcome Scale score at last follow-up examination was 1 in two patients, 2 in two patients, and 5 in two patients. CONCLUSION: The rate of rupture of aneurysms during coil embolization is approximately 2 to 4%. The clinical outcome may be related to the timing of the rupture and the number of coils placed before rupture. If extravasation of contrast agent is seen, which suggests intraprocedural rupture, further coil deposition should be attempted if safely possible.

Aged↗
PubMed2001

Lingual artery embolization for severe and uncontrollable postoperative tonsillar bleeding.

We performed emergent angiography of the external carotid artery to evaluate a patient who experienced uncontrollable oropharyngeal bleeding 3 days following an adenotonsillectomy. Angiography demonstrated a left lingual artery disruption and hemorrhage. We then performed a coil embolization of the left lingual artery, which immediately halted the hemorrhage. We conclude that coil embolization is a rapid and effective strategy for the management of massive, uncontrollable postoperative tonsillar bleeding.

Adenoidectomy↗
PubMed2000

The use of stents in the management of neurovascular disease: a review of historical and present status.

In the mid-1960s, radiologists began experimenting with stents for use in the peripheral vasculature in the hope of treating vascular insufficiency resulting from vessel stenosis in a nonsurgical manner. The 1990s saw stents move into the neurovascular arena for the management of a variety of disease processes, including arterial and venous sinus stenosis, arterial dissection, arterial aneurysms, and arteriovenous fistulae. This article reviews the current status of stenting in regard to the management of neurovascular maladies.

Angioplasty, Balloon↗
PubMed2000

Endovascular problem solving with intravascular stents.

BACKGROUND AND PURPOSE: Intravascular stents are being used with increasing frequency in interventional neuroradiology. They provide the potential to expand the therapeutic capabilities of the endovascular therapist and stand to revolutionize endovascular intervention within both the intracranial and extracranial vessels. We present our application of stent technology to further the understanding of endovascular rescue from procedural complications and the solving of complex clinical problems. METHODS: Three patients underwent unplanned placement of intravascular stents. In two patients a stent was used to provide stabilization of an irretrievable intravascular device; in the third patient a stent was used to provide a scaffolding for proximal external carotid sacrifice. RESULTS: Stent deployment was successful in all patients. The intravascular devices stabilized by stent placement included unraveled fragments of a Guglielmi detachable coil (GDC) and a partially deployed coronary stent. Proximal external carotid sacrifice was achieved with the aid of a stent in one patient to control hemorrhage from recurrence of laryngeal cancer. No periprocedural neurologic complications were encountered. Six-month follow-up angiography in one patient showed only minimal myointimal hyperplasia induced by stent-stabilized GDC fragments adjacent to the internal carotid vessel wall. CONCLUSION: Stents can be used to provide stabilization of irretrievable intravascular devices or as a scaffolding for proximal vessel sacrifice. These applications may allow endovascular rescue of procedural complications and solve unique clinical problems.

Aged↗
PubMed2000

Remote vascular catastrophes after neurovascular interventional therapy for type 4 Ehlers-Danlos Syndrome.

Type 4 Ehlers-Danlos Syndrome (EDS 4) is the most malignant form of Ehlers-Danlos Syndrome, often accompanied by neurovasacular complications secondary to vessel dissection or aneurysms. The fragile nature of connective tissue in these patients makes exovascular and endovascular treatment hazardous. We have treated four patients with EDS 4 over the last 8 years by using neuroendovascular procedures. Two of these individuals suffered remote vascular injuries around the time of their procedures and ultimately died. The circumstances surrounding their deaths will make up the body of this report.

Adolescent↗
PubMed1999

Brainstem compression as a cause of neurogenic hypertension.

Primary or essential hypertension affects more than 50 million Americans, more than 6 million of whom cannot achieve adequate control of their condition with medication. The current neurophysiologic literature indicates that some forms of primary hypertension may be secondary to compression of the left rostral ventrolateral medulla near the root entry zones of cranial nerves 9 and 10 by arteries or veins. Surgical brainstem decompression may alleviate this hypertension or make it medically controllable. This paper reviews the experimental, anatomic, and clinical literature that supports the neurogenic theory of hypertension.

Animals↗
PubMed1999

Multidisciplinary approach to traumatic intracranial aneurysms secondary to shotgun and handgun wounds.

BACKGROUND: Traumatic intracranial aneurysms (TICAs) may develop following gunshot injuries to the head. Management of these lesions often combines various aspects of microneurosurgical and endovascular techniques to safely repair or obliterate vessel defects. METHODS: We reviewed our experience over the last 18 years and identified five cases of intracranial aneurysms following gunshot and handgun wounds that were treated surgically and/or endovascularly. RESULTS: All patients had successful obliteration of their lesions using a variety of therapeutic modalities aimed at preserving neurologic function while at the same time eliminating the aneurysm from the circulation. CONCLUSION: Both microneurosurgery and endovascular surgery have important roles to play in the management of TICAs. In some cases, both methods can be combined to eliminate lesions and maximize patient recovery in a safe, efficient, and effective fashion.

Adult↗
PubMed1999

Dural waisting as a sign of subarachnoid extension of cavernous carotid aneurysms: a follow-up case report.

OBJECTIVE: Even when augmented by CT and MRI, it can be difficult on angiography to predict which intracavernous carotid artery aneurysms (ICCAA) have subarachnoid extension and therefore pose a higher risk of subarachnoid hemorrhage. Previously we reported a case of an ICCAA, which on angiogram had a focal tapering of the dome that we termed a "waist." At surgery this lesion was found to have subarachnoid extension. We postulated that this dural "waisting" on the arteriogram was a predictor of subarachnoid extension. Herein we report a second case of an ICCAA with the angiographic appearance of a waist that was also confirmed to have subarachnoid extension at surgery, thereby strengthening our original hypothesis. CLINICAL PRESENTATION: A 40-year-old woman presented with a 3-month history of bitemporal headache, diplopia, and a left sixth nerve palsy. MRI showed a lesion in the vicinity of the left cavernous carotid sinus and an arteriogram confirmed the presence of a large cavernous carotid aneurysm. As in the previous case, the aneurysm fundus was indented, creating a waist on the aneurysm dome. INTERVENTION: After passing a trial balloon occlusion of the involved carotid artery, the patient was brought to the operating room for lesion trapping. The aneurysm fundus was seen to extend beyond the falciform ligament and with subsequent dissection, the neck of the aneurysm was seen to incorporate the carotid artery distal to the ophthalmic artery. The aneurysm was trapped by ligating the internal carotid artery in the neck and by placing a clip on the intracranial carotid proximal to the posterior communicating artery. CONCLUSION: The presence of subarachnoid extension of an ICCAA can be difficult to elucidate on an arteriogram. This is an additional case in which a focal narrowing or "waisting" of the aneurysm dome seen on an angiogram served as a marker of subarachnoid extension.

Adult↗
PubMed1999

Percutaneous transluminal angioplasty and stenting of midbasilar stenoses: three technical case reports and literature review.

OBJECTIVE AND IMPORTANCE: Symptomatic basilar artery stenosis is a highly morbid disease process. Recent technological and pharmaceutical advances make endovascular treatment of this disease process possible. CLINICAL PRESENTATION: We report three cases of patients with a symptomatic basilar artery stenosis despite anticoagulation. INTERVENTION: All patients were successfully treated with a flexible coronary stent and perioperative antiplatelet medications without incident. Poststenting angiography demonstrated a normal-caliber artery with patent perforators. In one case, a poststenting cerebral blood flow study revealed improved perfusion. CONCLUSION: A new generation of stents and balloons makes access to intracranial intradural arterial pathological abnormalities possible. Such devices may well revolutionize the management of ischemic and hemorrhagic intracranial cerebrovascular disease.

Aged↗
PubMed1998

The use of cardiac troponin-I (cTnI) to determine the incidence of myocardial ischemia and injury in patients with aneurysmal and presumed aneurysmal subarachnoid hemorrhage.

A prospective single center study was performed to determine the minimal preoperative incidence of unrecognized cardiac injury in patients suffering aneurysmal and presumed aneurysmal subarachnoid hemorrhage (SAH). When caring for such patients in the pre- and post operative period clinicians must be aware of the possibility of cardiac injury even when a history of previous cardiac symptomatology is not present. Forty-seven consecutive patients suffering from SAH over a five-month period underwent serum measurements of the cardiac muscle marker troponin I (cTnI) immediately upon admission. Repeat studies, if possible, were done 24 hours later. EKG was performed in all patients and was available for review in 44 of the 47 cases. Echocardiography was performed in four of eight patients with elevated cTnI levels. Signs and symptoms relating to cardiac ischemia were recorded by the patients' physicians and nurses. Eight individuals (17%) had elevations in cardiac troponin I levels. Because surgical treatment is generally carried out as soon as possible following the hemorrhage, many patients with normal troponin I levels within twenty-four hours of their hemorrhage were operated upon before a repeat enzyme could be obtained or possibly before elevations could be recorded. In addition, a number of patients were referred to our center several days post-hemorrhage at a time when marker levels may have normalized. Therefore, the 17% incidence of elevated cTnI may be an underestimate. Only two of the eight patients had clinical abnormalities in cardiac function. Four patients with elevated levels had echocardiograms, three of which were abnormal. One additional patient died of a myocardial infarction before an echocardiogram could be obtained. EKG was abnormal in six of the seven patients with elevated troponin who had tracings available for review. Recordings consistent with recent myocardial ischemia were present in four of these. Of the 39 patients with negative troponin I levels, 37 had EKG available for review. None had recordings clearly consistent with recent myocardial ischemia although 13 were suggestive of ischemic changes. None of these 39 patients had pre- or post-operative clinical changes in cardiac function. Elevations in troponin I appeared to be unrelated to the patient's Hunt and Hess grade or Fisher score although our numbers were too small to draw any meaningful conclusions.

Adult↗