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Dwight Parkinson and Michael West

✓ Eleven cases of traumatic intracranial aneurysms, six saccular and five arteriovenous, are presented with an operative mortality of 22.2%, which compares favorably with the few reports in the literature. These lesions are usually associated with serious head injuries. The diagnosis is often delayed or overlooked as the surgeon's attention is distracted by the presence of an accompanying intracranial hematoma. With increasing replacement of angiography by computerized tomography in aneurysm diagnosis, these aneurysms are even more likely to escape detection. They should be suspected in any patient who deteriorates within 2 weeks of the trauma. Conservative management carries a mortality rate of about 50%. Because of their superficial location, they are amenable to successful surgical extirpation. Improved mortality depends on early recognition and surgical obliteration.

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Dwight Parkinson and Michael West

✓ A patient presented with spontaneous subarachnoid hemorrhage (SAH) from a cerebral arteriovenous malformation (AVM) which was later totally removed at surgery. The patient presented again with a new SAH from a spinal AVM that was also totally removed at surgery. Coexistence of spinal and cerebral arteriovenous malformations are exceedingly rare and hemorrhage from each is not previously reported. This case emphasizes the importance of investigating the spinal canal in otherwise unexplained spontaneous SAH.

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Mirek Stranc and Michael West

✓ A new surgical technique is described for the relief of the ocular manifestations of dysthyroid orbitopathy. Surgical decompression of the orbit was reserved for patients who failed to respond to medical treatment. Eleven patients (nine women and two men) were followed for periods from 3 to 48 months. Visual loss was the commonest presentation and the main indication for surgery. All patients had failed to respond to medical therapy, consisting of steroid and/or radiation therapy. Three patients had previously undergone orbital decompressions with limited success. Six patients had preoperative visual acuity of worse than 20/200. Preoperative exophthalmos ranged from 24 to 35 mm (normal 16 mm). The orbits were approached by a bifrontal scalp flap with exposure of the temporal and infratemporal fossae. The orbital roof was approached transcranially. The posterior wall of the frontal sinus was removed together with the mucous lining. To maximize the decompression, the periosteum surrounding the orbital contents was incised, allowing the contents to prolapse through the newly created windows into the maxillary antrum, temporal fossa, anterior cranial fossa, and nose. During the past 3 years, 22 orbits in 11 patients have been decompressed by this technique. Symptomatic relief was obtained in all but one patient who still had significant exophthalmos with keratitis, but did have a dramatic improvement in vision. The decrease in exophthalmos ranged from 1 to 13 mm (mean 7 mm). The most dramatic improvement was in vision, with postoperative acuity of 20/20 to 20/30 in all but two patients. There were no deaths and no major morbidity.

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Christopher B. Shields and Michael West

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James L. West, Michael H. Soike, Jaclyn J. Renfrow, Michael D. Chan, Adrian W. Laxton and Stephen B. Tatter

OBJECTIVE

Rathke’s cleft cysts (RCCs) are benign lesions of the sella turcica that usually come to neurosurgical attention due to compression of the optic apparatus (OA) and headaches. Treatment options for these lesions include observation, aspiration of cyst contents, or open resection of the cyst with the cyst wall. All of these options involve the potential for cyst recurrence or enlargement. In this study the authors report on a potential new therapeutic option for RCCs, i.e., stereotactic radiosurgery (SRS).

METHODS

A retrospective review was conducted of 5 patients with histologically confirmed, multiply recurrent RCCs who were treated with single-fraction SRS at a tertiary referral academic medical center.

RESULTS

The total cohort consisted of 5 female patients with an average age of 31.8 years. The most common presenting symptom was headache followed by blurry vision. The symptoms were present on average for 7 months before intervention. The median number of surgeries prior to radiosurgery was 2. The average volume of lesion treated was 0.34 cm3. The median SRS dose was 12.5 Gy prescribed to the 50% isodose line with an average prescription coverage of 96.6%. The median dose to the OA was 5 Gy. At last follow-up, 3 of 5 cysts had completely regressed, 1 had regressed by more than 50% but was still present, and 1 was stable, with an overall mean follow-up duration of 34.2 months. There were no neurological, endocrinological, or visual complications attributable to SRS during the follow-up period.

CONCLUSIONS

RCCs can be a challenging clinical entity to treat, especially when they are multiply recurrent. In patients with an average of 2 previous surgeries for resection, a single SRS session prevented recurrence universally, with an average follow-up of almost 3 years. These results indicate that further investigation of the treatment of RCCs with SRS is indicated.

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Nimodipine treatment in poor-grade aneurysm patients

Results of a multicenter double-blind placebo-controlled trial

Kenneth C. Petruk, Michael West, Gerard Mohr, Bryce K. A. Weir, Brien G. Benoit, Fred Gentili, Lew B. Disney, Moe I. Khan, Michael Grace, Renn O. Holness, Melinda S. Karwon, Robert M. Ford, G. Stuart Cameron, William S. Tucker, G. Barrie Purves, Jack D. R. Miller, K. Michael Hunter, Michael T. Richard, Felix A. Durity, Richard Chan, Lawrence J. Clein, Falah B. Maroun and Alain Godon

✓ A multicenter, randomized placebo-controlled double-blind trial of nimodipine in poor-grade aneurysm patients was carried out in 17 Canadian hospitals. Of 188 patients enrolled in the trial, 32 were excluded for protocol violations and two were excluded due to statistical considerations, leaving 154 patients for valid outcome analysis. Nimodipine treatment was associated with a significantly better outcome (p < 0.001): 21 (29.2%) of 72 nimodipine-treated patients had a good outcome at 3 months after subarachnoid hemorrhage (SAH) compared to eight (9.8%) of 82 placebo-treated patients. Delayed ischemic deficits from vasospasm alone were significantly less frequent in the nimodipine group (p < 0.05) with permanent deficits occurring in five nimodipine-treated patients (6.9%) and in 22 placebo-treated patients (26.8%). Improvement in the good outcome rate and reduction in delayed ischemic deficits from vasospasm alone occurred in both Grade 3 and 4 patients, with no difference between nimodipine- and placebo-treated patients being found in Grade 5 patients.

Repeat angiography after Day 4 was carried out in 124 patients. There was no significant difference in the incidence of moderate or severe diffuse spasm, which was seen in 64.3% of nimodipine-treated patients and 66.2% of placebo-treated patients. The authors conclude that nimodipine treatment in poor-grade patients with SAH results in an increase in the number of good outcomes and a reduction in the incidence of delayed neurological deterioration due to vasospasm. This effect occurs by a mechanism other than prevention of large-vessel spasm as visualized on angiography.

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Jacob K. Greenberg, Donna B. Jeffe, Christopher R. Carpenter, Yan Yan, Jose A. Pineda, Angela Lumba-Brown, Martin S. Keller, Daniel Berger, Robert J. Bollo, Vijay M. Ravindra, Robert P. Naftel, Michael C. Dewan, Manish N. Shah, Erin C. Burns, Brent R. O’Neill, Todd C. Hankinson, William E. Whitehead, P. David Adelson, Mandeep S. Tamber, Patrick J. McDonald, Edward S. Ahn, William Titsworth, Alina N. West, Ross C. Brownson and David D. Limbrick Jr.

OBJECTIVE

There remains uncertainty regarding the appropriate level of care and need for repeating neuroimaging among children with mild traumatic brain injury (mTBI) complicated by intracranial injury (ICI). This study’s objective was to investigate physician practice patterns and decision-making processes for these patients in order to identify knowledge gaps and highlight avenues for future investigation.

METHODS

The authors surveyed residents, fellows, and attending physicians from the following pediatric specialties: emergency medicine; general surgery; neurosurgery; and critical care. Participants came from 10 institutions in the United States and an email list maintained by the Canadian Neurosurgical Society. The survey asked respondents to indicate management preferences for and experiences with children with mTBI complicated by ICI, focusing on an exemplar clinical vignette of a 7-year-old girl with a Glasgow Coma Scale score of 15 and a 5-mm subdural hematoma without midline shift after a fall down stairs.

RESULTS

The response rate was 52% (n = 536). Overall, 326 (61%) respondents indicated they would recommend ICU admission for the child in the vignette. However, only 62 (12%) agreed/strongly agreed that this child was at high risk of neurological decline. Half of respondents (45%; n = 243) indicated they would order a planned follow-up CT (29%; n = 155) or MRI scan (19%; n = 102), though only 64 (12%) agreed/strongly agreed that repeat neuroimaging would influence their management. Common factors that increased the likelihood of ICU admission included presence of a focal neurological deficit (95%; n = 508 endorsed), midline shift (90%; n = 480) or an epidural hematoma (88%; n = 471). However, 42% (n = 225) indicated they would admit all children with mTBI and ICI to the ICU. Notably, 27% (n = 143) of respondents indicated they had seen one or more children with mTBI and intracranial hemorrhage demonstrate a rapid neurological decline when admitted to a general ward in the last year, and 13% (n = 71) had witnessed this outcome at least twice in the past year.

CONCLUSIONS

Many physicians endorse ICU admission and repeat neuroimaging for pediatric mTBI with ICI, despite uncertainty regarding the clinical utility of those decisions. These results, combined with evidence that existing practice may provide insufficient monitoring to some high-risk children, emphasize the need for validated decision tools to aid the management of these patients.

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Jason P. Sheehan, Robert M. Starke, Hideyuki Kano, Anthony M. Kaufmann, David Mathieu, Fred A. Zeiler, Michael West, Samuel T. Chao, Gandhi Varma, Veronica L. S. Chiang, James B. Yu, Heyoung L. McBride, Peter Nakaji, Emad Youssef, Norissa Honea, Stephen Rush, Douglas Kondziolka, John Y. K. Lee, Robert L. Bailey, Sandeep Kunwar, Paula Petti and L. Dade Lunsford

Object

Parasellar and sellar meningiomas are challenging tumors owing in part to their proximity to important neurovascular and endocrine structures. Complete resection can be associated with significant morbidity, and incomplete resections are common. In this study, the authors evaluated the outcomes of parasellar and sellar meningiomas managed with Gamma Knife radiosurgery (GKRS) both as an adjunct to microsurgical removal or conventional radiation therapy and as a primary treatment modality.

Methods

A multicenter study of patients with benign sellar and parasellar meningiomas was conducted through the North American Gamma Knife Consortium. For the period spanning 1988 to 2011 at 10 centers, the authors identified all patients with sellar and/or parasellar meningiomas treated with GKRS. Patients were also required to have a minimum of 6 months of imaging and clinical follow-up after GKRS. Factors predictive of new neurological deficits following GKRS were assessed via univariate and multivariate analyses. Kaplan-Meier analysis and Cox multivariate regression analysis were used to assess factors predictive of tumor progression.

Results

The authors identified 763 patients with sellar and/or parasellar meningiomas treated with GKRS. Patients were assessed clinically and with neuroimaging at routine intervals following GKRS. There were 567 females (74.3%) and 196 males (25.7%) with a median age of 56 years (range 8–90 years). Three hundred fifty-five patients (50.7%) had undergone at least one resection before GKRS, and 3.8% had undergone prior radiation therapy. The median follow-up after GKRS was 66.7 months (range 6–216 months). At the last follow-up, tumor volumes remained stable or decreased in 90.2% of patients. Actuarial progression-free survival rates at 3, 5, 8, and 10 years were 98%, 95%, 88%, and 82%, respectively. More than one prior surgery, prior radiation therapy, or a tumor margin dose < 13 Gy significantly increased the likelihood of tumor progression after GKRS.

At the last clinical follow-up, 86.2% of patients demonstrated no change or improvement in their neurological condition, whereas 13.8% of patients experienced symptom progression. New or worsening cranial nerve deficits were seen in 9.6% of patients, with cranial nerve (CN) V being the most adversely affected nerve. Functional improvements in CNs, especially in CNs V and VI, were observed in 34% of patients with preexisting deficits. New or worsened endocrinopathies were demonstrated in 1.6% of patients; hypothyroidism was the most frequent deficiency. Unfavorable outcome with tumor growth and accompanying neurological decline was statistically more likely in patients with larger tumor volumes (p = 0.022) and more than 1 prior surgery (p = 0.021).

Conclusions

Gamma Knife radiosurgery provides a high rate of tumor control for patients with parasellar or sellar meningiomas, and tumor control is accompanied by neurological preservation or improvement in most patients.