Pituitary

Benefiting from superior tissue contrast, multi‐planar capability and lack of bone artifact, MRI readily depicts complex anatomy in and about the pituitary gland. This unit presents three basic protocols for common indications relating to pathology of the sella and parasellar region. The protocols differ in emphasis more than in concept, and share a basic theme of thin slice high‐resolution imaging including the use of gadolinium. With the possible exception of dynamic imaging, all protocols may be readily performed on any MR scanner.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145371/1/cpmia0502.pd

Dementia

This unit presents specific protocols intended to maximize the contribution of MRI to the clinical evaluation of dementia. Each protocol has, as its foundation, a wholeâ brain screen designed to evaluate for treatable causes of dementia. Reflecting the frequent overlap of vascular disease with dementing illness, the screening protocol also serves as an optimal evaluation of the patient with suspected vascular dementia. Additional sequences or modifications are then used to answer specific clinical questions. The parameters given here are derived from experience at 1.5 T and may need to be altered slightly depending on the field strength and the equipment manufacturer.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145357/1/cpmia0503.pd

Factors predicting outcome of surgery for intractable epilepsy with pathologically verified mesial temporal sclerosis.

PURPOSE: To examine the subgroup of patients with medically intractable epilepsy receiving temporal lobectomies who have pathologically verified mesial temporal sclerosis (MTS) and to determine the relation of demographic and clinical factors, results of diagnostic testing, and details of the surgical procedure with prognosis for achieving control of seizures. METHODS: All patients receiving surgical treatment for intractable epilepsy between 1991 and 1998 at the University of Washington were reviewed. There were 118 patients who met inclusion criteria of adequate pathological analysis showing MTS without a progressive process and a minimum of 1-year follow-up. RESULTS: Only personal history of status epilepticus demonstrated significant (p = 0.0276) prediction of outcome, increasing the risk of surgical failure. No other factors were significant predictors of outcome, including history of febrile seizures, possible etiologic factors, EEG, magnetic resonance imaging (MRI) or neuropsychological testing results, or extent of resection. CONCLUSIONS: Many factors that have been previously described to predict favorable outcome in the overall group of patients receiving temporal lobe resections for intractable epilepsy are, in fact, predictors of MTS and lose their predictive value when the subgroup of patients with confirmed MTS is examined. Neurosurgical treatment of MTS can be very effective even in the presence of significant etiologic factors, or of bilateral or extratemporal abnormalities on EEG or MRI

Which Arteries Are Expendable? The Practice and Pitfalls of Embolization throughout the Body

This article outlines general concepts of, and strategies for, therapeutic embolization throughout the body, touching on all major arterial distributions. Clinical scenarios that allow or prevent safe embolization of vessels are presented. Specific agents are recommended where appropriate, as are alternate approaches when embolization is not an option. Pre-embolization precautions and adjunctive measures are described in high-risk areas

Targeted embolization of aneurysms associated with brain arteriovenous malformations at high risk for surgical resection: A case-control study

BACKGROUND: High-risk components of brain arteriovenous malformations (BAVMs) can be targeted to reduce the risk of lesion rupture. OBJECTIVE: To evaluate targeted embolization of aneurysms against other means of treatment with a case–control analysis; we previously investigated this approach associated with BAVMs. METHODS: Retrospective analysis of patients with BAVMs was performed, identifying patients treated with intention to occlude only an aneurysm associated with a BAVM. For each targeted aneurysm embolization (TAE) patient identified, 4 control patients were randomly selected, controlling for rupture status, age, and Spetzler-Martin plus Lawton-Young supplemental score. Analysis was performed to compare rates of adverse events (hemorrhage, new seizure, and death) between the 2 groups. RESULTS: Thirty-two patients met inclusion criteria, and 128 control patients were identified, out of 1103 patients treated during the study period. Thirty-four adverse events occurred (15 ruptures, 15 new seizures, and 11 deaths) during the follow-up period (mean 1157 d for the TAE cohort and 1036 d for the non-TAE cohort). Statistically lower associations were noted for the TAE group for any adverse event (hazard ratio 0.28, P = .037) and the composite outcome of hemorrhage or new seizure (hazard ratio 0.20, P = .029). CONCLUSION: For BAVMs at high risk for surgical resection, TAE can be performed safely and effectively. Patients treated with TAE had better outcomes than matched patients undergoing other combinations of treatment. TAE can be considered for BAVMs with high operative risk prior to radiosurgery or when no other treatment options are available

Targeted Embolization of Aneurysms Associated With Brain Arteriovenous Malformations at High Risk for Surgical Resection: A Case-Control Study.

BackgroundHigh-risk components of brain arteriovenous malformations (BAVMs) can be targeted to reduce the risk of lesion rupture.ObjectiveTo evaluate targeted embolization of aneurysms against other means of treatment with a case-control analysis; we previously investigated this approach associated with BAVMs.MethodsRetrospective analysis of patients with BAVMs was performed, identifying patients treated with intention to occlude only an aneurysm associated with a BAVM. For each targeted aneurysm embolization (TAE) patient identified, 4 control patients were randomly selected, controlling for rupture status, age, and Spetzler-Martin plus Lawton-Young supplemental score. Analysis was performed to compare rates of adverse events (hemorrhage, new seizure, and death) between the 2 groups.ResultsThirty-two patients met inclusion criteria, and 128 control patients were identified, out of 1103 patients treated during the study period. Thirty-four adverse events occurred (15 ruptures, 15 new seizures, and 11 deaths) during the follow-up period (mean 1157 d for the TAE cohort and 1036 d for the non-TAE cohort). Statistically lower associations were noted for the TAE group for any adverse event (hazard ratio 0.28, P = .037) and the composite outcome of hemorrhage or new seizure (hazard ratio 0.20, P = .029).ConclusionFor BAVMs at high risk for surgical resection, TAE can be performed safely and effectively. Patients treated with TAE had better outcomes than matched patients undergoing other combinations of treatment. TAE can be considered for BAVMs with high operative risk prior to radiosurgery or when no other treatment options are available

Delayed Onset of Mixed Cranial Neuropathies and Cluster Headache After Embolization of Indirect Carotid-Cavernous Fistula

Carotid cavernous fistulas (CCF) often present with diplopia secondary to cranial nerve palsy (CNP). Immediate development of postoperative CNP has been described in the literature. This study described delayed- onset of CNP after complete and reconfirmed obliteration of the CCF and resolution of initial CN

Safety and Efficacy of Preoperative Embolization of Intracranial Hemangioblastomas

BACKGROUND: Intracranial hemangioblastomas are highly vascular tumors that account for 1% to 2% of all central nervous system tumors. Preoperative embolization has been proposed to limit the often significant intraoperative blood loss associated with resection and potentially make the tumor more soft/necrotic and thus more amenable to gross total resection. The safety and efficacy of preoperative embolization of intracranial hemangioblastomas, however, are not well characterized. OBJECTIVE: To evaluate the safety and efficacy of preoperative endovascular embolization of intracranial hemangioblastomas using a variety of embolic agents. METHODS: A retrospective review of all surgically resected intracranial hemangioblastomas treated with preoperative embolization between 1999 and 2014 at 2 high-volume centers was performed. Clinical and radiographic criteria, including von Hippel-Lindau status, magnetic resonance imaging tumor characteristics, embolization-related complications, degree of angiographic devascularization, intraoperative blood loss, ability to obtain gross total resection, transfusion requirements, and operative time, were analyzed. RESULTS: A total of 54 patients underwent surgery, with 24 undergoing preoperative embolization followed by surgical resection, and 30 patients undergoing surgical resection alone. Embolization-related neurological complications were seen in 6 patients (25%), including 3 hemorrhages when polyvinyl alcohol particles (P .04) were used and 3 infarctions when liquid embolic agents were used (P .27). Permanent neurological deficits were seen in 15%. CONCLUSION: Preoperative embolization of intracranial hemangioblastomas should be performed with caution, given the potential for neurological morbidity. Further studies are needed to help guide patient and embolic agent selection