Biomedical subjects

Michael J Alexander

Publications and source records attributed to Michael J Alexander.

23 records · Page 2Linked to original sources

PubMed2002

De novo cerebral arteriovenous malformation: case report.

OBJECTIVE AND IMPORTANCE: Arteriovenous malformations (AVMs) are generally thought to have a congenital cause. This is the first report of an angiographically proven de novo cerebral AVM in an adult patient without previous vascular abnormality. CLINICAL PRESENTATION: A 26-year-old African-American woman developed multiple cranial nerve deficits and ataxia over the course of a few days after a streptococcal throat infection. T2-weighted magnetic resonance imaging scans revealed a hyperintense signal in the midbrain with extension into the diencephalon. A cerebral angiogram performed at that time to exclude vasculitis revealed normal cerebral vasculature. The patient was treated with corticosteroids, and symptoms resolved. Subsequently, at the age of 32, this patient presented with a severe headache and emesis, but with no focal neurological deficit. INTERVENTION: The patient's cranial computed tomographic and magnetic resonance imaging scans revealed a right posterior temporal intraparenchymal hemorrhage, and cerebral angiography revealed a new 3- by 2-cm AVM. The patient underwent microsurgical resection of the AVM and associated hematoma. Postoperative angiography revealed no evidence of residual AVM. CONCLUSION: This study details the case of a woman who developed a de novo cerebral AVM during a 6-year period. This report challenges the conventional belief that all AVMs have a congenital cause.

Adult↗

PubMed2002

Extradural thoracic arteriovenous malformation in a patient with Klippel-Trenaunay-Weber syndrome: case report.

OBJECTIVE AND IMPORTANCE: Spinal cord involvement in Klippel-Trenaunay-Weber (KTW) syndrome is rare. Cases of intradural spinal cord arteriovenous malformations (AVMs) have been associated with this syndrome. Likewise, cases of epidural hemangioma and angiomyolipoma have been reported to occur at the same segmental level as cutaneous hemangioma in KTW syndrome. This report details a rare case of an extradural thoracic AVM in a patient with KTW syndrome. CLINICAL PRESENTATION: A 30-year-old man presented with a 10-month history of progressive myelopathy, bilateral lower-extremity weakness, and numbness, with the right side affected more than the left. His symptoms had progressed to the point that he was unable to walk. The patient had the characteristic manifestations of KTW syndrome, including numerous cutaneous angiomas and cavernomas, limb hypertrophy and syndactyly, and limb venous malformations. A magnetic resonance imaging scan and subsequent angiogram demonstrated a large extradural AVM causing cord compression at the T3-T4 levels. INTERVENTION: The patient underwent two separate endovascular procedures, including embolization of upper thoracic and thyrocervical trunk feeders. Subsequently, he underwent T1-T4 laminectomy and microsurgical excision of the AVM. Clinically, the patient improved such that he could walk without assistance. CONCLUSION: KTW syndrome represents a spectrum of clinical presentations. Although involvement of the spinal cord is uncommon, the manifestations of this syndrome may include both intradural and extradural AVMs in addition to various tumors.

Adult↗

PubMed2002

Intracerebral hemorrhages associated with neurointerventional procedures using a combination of antithrombotic agents including abciximab.

BACKGROUND: We report the occurrence of fatal intracerebral hemorrhage associated with using a combination of antithrombotic agents, including abciximab, in patients undergoing neurointerventional procedures. SUMMARY OF REPORT: Seven patients (average age 60, range 46 to 73 years) developed fatal intracerebral hemorrhages associated with neurointerventional procedures and the use of intravenous abciximab. The procedures included angioplasty and stent placement in the cervical internal carotid artery (n=4), angioplasty of the intracranial internal carotid artery (n=1), and angioplasty of the middle cerebral artery (n=2). Clinical deterioration was observed within 1 hour of the procedure in 5 patients and 7 and 8 hours after the procedure, respectively, in the remaining 2 patients. All patients had received heparin and clopidogrel; 6 had also received aspirin. CONCLUSIONS: Intracerebral hemorrhages can occur after neurointerventional procedures in patients with recent cerebral ischemic events, particularly when aggressive antithrombotic treatment is used.

Abciximab↗

PubMed2002

Dynamic CT perfusion imaging with acetazolamide challenge for the preprocedural evaluation of a patient with symptomatic middle cerebral artery occlusive disease.

We describe the use of a CT-based method of cerebral perfusion imaging, dynamic CT perfusion imaging, for the pre- and postprocedural assessment of cerebral blood flow in a patient with symptomatic middle cerebral artery occlusive disease who underwent balloon angioplasty with stent placement in the affected artery. Dynamic CT perfusion imaging represents a widely available and minimally invasive alternative to other available methods of cerebral perfusion imaging.

Acetazolamide↗

PubMedDate not supplied

Primary endovascular therapy with clot retrieval and balloon angioplasty for acute basilar artery occlusion.

This case report demonstrates that mechanical clot disruption and retrieval may be performed safely and successfully in a child with basilar artery (BA) thrombosis. A 16-year-old boy presented to our institution with locked-in syndrome 20 h after symptom onset. Brain MRI and cerebral angiography findings were consistent with BA occlusion. The child underwent endovascular therapy with clot retrieval followed by balloon angioplasty achieving immediate recanalization and clinical recovery on 3-month follow-up. This case highlights the use of primary neurointerventional devices in children with BA occlusion presenting beyond the conventional therapeutic window for other interventions.

Acute Disease↗