Search Results

You are looking at 11 - 20 of 22 items for

  • Author or Editor: Keith M. Rich x
Clear All Modify Search
Restricted access

Josser E. Delgado Almandoz, Bharathi D. Jagadeesan, Daniel Refai, Christopher J. Moran, DeWitte T. Cross III, Michael R. Chicoine, Keith M. Rich, Michael N. Diringer, Ralph G. Dacey Jr., Colin P. Derdeyn and Gregory J. Zipfel

Object

The yield of CT angiography (CTA) and MR angiography (MRA) in patients with subarachnoid hemorrhage (SAH) who have a negative initial catheter angiogram is currently not well understood. This study aims to determine the yield of CTA and MRA in a prospective cohort of patients with SAH and a negative initial catheter angiogram.

Methods

From January 1, 2005, until September 1, 2010, the authors instituted a prospective protocol in which patients with SAH—as documented by noncontrast CT or CSF xanthochromia and a negative initial catheter angiogram— were evaluated using CTA and MRA to assess for causative cerebral aneurysms. Two neuroradiologists independently evaluated the noncontrast CT scans to determine the SAH pattern (perimesencephalic or not) and the CT and MR angiograms to assess for causative cerebral aneurysms.

Results

Seventy-seven patients were included, with a mean age of 52.8 years (median 54 years, range 19–88 years). Fifty patients were female (64.9%) and 27 male (35.1%). Forty-three patients had nonperimesencephalic SAH (55.8%), 29 patients had perimesencephalic SAH (37.7%), and 5 patients had CSF xanthochromia (6.5%). Computed tomography angiography demonstrated a causative cerebral aneurysm in 4 patients (5.2% yield), all of whom had nonperimesencephalic SAH (9.3% yield). Mean aneurysm size was 2.6 mm (range 2.1–3.3 mm). Magnetic resonance angiography demonstrated only 1 of these aneurysms. No causative cerebral aneurysms were found in patients with perimesencephalic SAH or CSF xanthochromia.

Conclusions

Computed tomography angiography is a valuable adjunct in the evaluation of patients with nonperimesencephalic SAH who have a negative initial catheter angiogram, demonstrating a causative cerebral aneurysm in 9.3% of patients.

Restricted access

Colin P. Derdeyn, DeWitte T. Cross III, Christopher J. Moran, George W. Brown, Thomas K. Pilgram, Michael N. Diringer, Robert L. Grubb Jr., Keith M. Rich, Michael R. Chicoine and Ralph G. Dacey Jr.

Object. Ischemic stroke or transient ischemic attack (TIA) may occur after the treatment of intracranial aneurysms with Guglielmi detachable coils (GDCs). The purpose of the present study is to investigate possible risk factors for thromboembolic events and to determine their frequency and time course.

Methods. The records of 178 consecutive patients with 193 treated intracranial saccular aneurysms were reviewed. A total of 159 GDC procedures were performed to treat 143 aneurysms in 133 of those patients who were in good neurological condition, allowing clinical detection of postprocedure ischemic events (TIA or stroke). The association of clinical, anatomical, and pharmacological factors with intraprocedure intraarterial thrombus and with postprocedure ischemic events was investigated by using uni- and multivariate analyses.

Thrombus protruding into the parent artery was noted during six of 159 GDC procedures, resulting in a clinical deficit in one patient. No factor was associated with intraprocedure intraarterial thrombus. Ten postprocedure ischemic events occurred in nine patients. Seven events occurred within 24 hours, and three events occurred between 24 hours and 58 days. Aneurysm diameter and protruding coils were significant independent predictors of postprocedure ischemic events in multivariate analysis (both p = 0.02). The actuarial risk of stroke was 3.8%.

Conclusions. Larger aneurysm diameter and protruding loops of coils are associated with postprocedure ischemic events after GDC placement. It is unlikely that GDC-treated aneurysms retain thromboembolic potential beyond 2 months.

Restricted access

Manish N. Shah, James A. Botros, Thomas K. Pilgram, Christopher J. Moran, DeWitte T. Cross III, Michael R. Chicoine, Keith M. Rich, Ralph G. Dacey Jr., Colin P. Derdeyn and Gregory J. Zipfel

Object

The goal of this study was to determine the clinical course of Borden-Shucart Type I cranial dural arteriovenous fistulas (DAVFs) and to calculate the annual rate of conversion of these lesions to more aggressive fistulas that have cortical venous drainage (CVD).

Methods

A retrospective chart review was conducted of all patients harboring DAVFs who were seen at the authors' institution between 1997 and 2009. Twenty-three patients with Type I DAVFs who had available clinical follow-up were identified. Angiographic and clinical data from these patients were reviewed. Neurological outcome and status of presenting symptoms were assessed during long-term follow-up.

Results

Of the 23 patients, 13 underwent endovascular treatment for intolerable tinnitus or ophthalmological symptoms, and 10 did not undergo treatment. Three untreated patients died of unrelated causes. In those who were treated, complete DAVF obliteration was achieved in 4 patients, and palliative reduction in DAVF flow was achieved in 9 patients. Of the 19 patients without radiographic cure, no patient developed intracranial hemorrhage or nonhemorrhagic neurological deficits (NHNDs), and no patient died of DAVF-related causes over a mean follow-up of 5.6 years. One patient experienced a spontaneous, asymptomatic obliteration of a partially treated DAVF in late follow-up, and 2 patients experienced a symptomatic conversion of their DAVF to a higher-grade fistula with CVD in late follow-up. The annual rate of conversion to a higher-grade DAVF based on Kaplan-Meier cumulative event-free survival analysis was 1.0%. The annual rate of intracranial hemorrhage, NHND, and DAVF-related death was 0.0%.

Conclusions

A small number of Type I DAVFs will convert to more aggressive DAVFs with CVD over time. This conversion to a higher-grade DAVF is typically heralded by a change in patient symptoms. Follow-up vascular imaging is important, particularly in the setting of recurrent or new symptoms.

Restricted access

Chad W. Washington, Gregory J. Zipfel, Michael R. Chicoine, Colin P. Derdeyn, Keith M. Rich, Christopher J. Moran, DeWitte T. Cross and Ralph G. Dacey Jr.

Object

The purpose of aneurysm surgery is complete aneurysm obliteration while sparing associated arteries. Indocyanine green (ICG) videoangiography is a new technique that allows for real-time evaluation of blood flow in the aneurysm and vessels. The authors performed a retrospective study to compare the accuracy of ICG videoangiography with intraoperative angiography (IA), and determine if ICG videoangiography can be used without follow-up IA.

Methods

From June 2007 through September 2009, 155 patients underwent craniotomies for clipping of aneurysms. Operative summaries, angiograms, and operative and ICG videoangiography videos were reviewed. The number, size, and location of aneurysms, the ICG videoangiography and IA findings, and the need for clip adjustment after ICG videoangiography and IA were recorded. Discordance between ICG videoangiography and IA was defined as ICG videoangiography demonstrating aneurysm obliteration and normal vessel flow, but post-IA showing either an aneurysmal remnant and/or vessel occlusion requiring clip adjustment.

Results

Thirty-two percent of patients (49 of 155) underwent both ICG videoangiography and IA. The post-ICG videoangiography clip adjustment rate was 4.1% (2 of 49). The overall rate of ICG videoangiography–IA agreement was 75.5% (37 of 49) and the ICG videoangiography–IA discordance rate requiring post-IA clip adjustment was 14.3% (7 of 49). Adjustments were due to 3 aneurysmal remnants and 4 vessel occlusions. These adjustments were attributed to obscuration of the residual aneurysm or the affected vessel from the field of view and the presence of dye in the affected vessel via collateral flow. Although not statistically significant, there was a trend for ICG videoangiography–IA discordance requiring clip adjustment to occur in cases involving the anterior communicating artery complex, with an odds ratio of 3.3 for ICG videoangiography–IA discordance in these cases.

Conclusions

These results suggest that care should be taken when considering ICG videoangiography as the sole means for intraoperative evaluation of aneurysm clip application. The authors further conclude that IA should remain the gold standard for evaluation during aneurysm surgery. However, a combination of ICG videoangiography and IA may ultimately prove to be the most effective strategy for maximizing the safety and efficacy of aneurysm surgery.

Restricted access

Wilson Z. Ray, Russel G. Strom, Spiros L. Blackburn, William W. Ashley Jr., Gregorio A. Sicard and Keith M. Rich

Object

The aim of this study was to determine the efficacy of venous ultrasonography in screening for deep venous thrombosis (DVT) after subarachnoid hemorrhage (SAH). A large cohort of patients who had suffered SAH was evaluated with the primary end points of ascertaining the incidence of asymptomatic DVT with venous Doppler ultrasonography screening and of identifying risk factors for the development of DVT and subsequent pulmonary embolism.

Methods

Data from patients with aneurysmal SAH who had been admitted to the neurosurgical intensive care unit (ICU) between December 2002 and October 2006 were retrospectively evaluated. Patients who had undergone surgical or endovascular treatment of an aneurysm following SAH and survived ≥ 15 days were included in the study.

Results

The overall incidence of DVT among the entire study cohort was 18%. A subgroup analysis identified all patients, with or without symptoms for DVT, who had undergone venous Doppler ultrasonography screening. The incidence of asymptomatic DVT was 24%. Univariate analysis of all patients revealed a significant correlation between the risk of DVT and Hunt and Hess grade (r = 0.38, p < 0.0001), Fisher grade (r = 0.31, p < 0.0001), total hospital stay (r = 0.49, p < 0.0001), and number of days in the ICU (r = 0.48, p < 0.0001). Multivariate analysis demonstrated that the total hospital stay and number of days in the ICU were significant predictors of DVT in all patients (p < 0.0001 and p < 0.0002, respectively). In the subgroup of screened patients, Hunt and Hess grade, total hospital stay, and number of days in the ICU were significant predictors of DVT. Although screened patients were more likely to have DVT (χ2 = 6.0976, p < 0.02), there was no significant difference in the incidence of DVT or pulmonary embolism between patients who did and those who did not undergo routine lower-extremity Doppler ultrasonography screening.

Conclusions

Routine compressive venous Doppler ultrasonography is an efficient, noninvasive means of identifying DVT as a screening modality in both symptomatic and asymptomatic patients following aneurysmal SAH. The ability to confirm or deny the presence of DVT in this patient population allows one to better identify the indications for chemoprophylaxis. Prophylaxis for venous thromboembolism in neurosurgical patients is common. Emerging literature and anecdotal experience have exposed risks of complications with prophylactic anticoagulation protocols. The identification of patients at high risk—for example, those with asymptomatic DVT—will allow physicians to better assess the role of prophylactic anticoagulation.

Full access

Terrence F. Holekamp, Matthew E. Mollman, Rory K. J. Murphy, Grant R. Kolar, Neha M. Kramer, Colin P. Derdeyn, Christopher J. Moran, Richard J. Perrin, Keith M. Rich, Giuseppe Lanzino and Gregory J. Zipfel

Nonhemorrhagic neurological deficits are underrecognized symptoms of intracranial dural arteriovenous fistulas (dAVFs) having cortical venous drainage. These symptoms are the consequence of cortical venous hypertension and portend a clinical course with increased risk of neurological morbidity and mortality. One rarely documented and easily misinterpreted type of nonhemorrhagic neurological deficit is progressive dementia, which can result from venous hypertension in the cortex or in bilateral thalami. The latter, which is due to dAVF drainage into the deep venous system, is the less common of these 2 dementia syndromes. Herein, the authors report 4 cases of dAVF with venous drainage into the vein of Galen causing bithalamic edema and rapidly progressive dementia. Two patients were treated successfully with endovascular embolization, and the other 2 patients were treated successfully with endovascular embolization followed by surgery. The radiographic abnormalities and presenting symptoms rapidly resolved after dAVF obliteration in all 4 cases. Detailed descriptions of these 4 cases are presented along with a critical review of 15 previously reported cases. In our analysis of these 19 published cases, the following were emphasized: 1) the clinical and radiographic differences between dAVF-induced thalamic versus cortical dementia syndromes; 2) the differential diagnosis and necessary radiographic workup for patients presenting with a rapidly progressive thalamic dementia syndrome; 3) the frequency at which delays in diagnosis occurred and potentially dangerous and avoidable diagnostic procedures were used; and 4) the rapidity and completeness of symptom resolution following dAVF treatment.

Restricted access

Spiros L. Blackburn, William W. Ashley Jr., Keith M. Rich, Joseph R. Simpson, Robert E. Drzymala, Wilson Z. Ray, Christopher J. Moran, DeWitte T. Cross III, Michael R. Chicoine, Ralph G. Dacey Jr., Colin P. Derdeyn and Gregory J. Zipfel

Object

Large cerebral arteriovenous malformations (AVMs) are often not amenable to direct resection or stereotactic radiosurgery (SRS) treatment. An alternative treatment strategy is staged endovascular embolization followed by SRS (Embo/SRS). The object of this study was to examine the experience at Washington University in St. Louis with Embo/SRS for large AVMs and review the results in earlier case series.

Methods

Twenty-one cases involving patients with large AVMs treated with Embo/SRS between 1994 and 2006 were retrospectively evaluated. The AVM size (before and after embolization), procedural complications, radiological outcome, and neurological outcome were examined. Radiological success was defined as AVM obliteration as demonstrated by catheter angiography, CT angiography, or MR angiography. Radiological failure was defined as residual AVM as demonstrated by catheter angiography, CT angiography, or MR angiography performed at least 3 years after SRS.

Results

The maximum diameter of all AVMs in this series was > 3 cm (mean 4.2 cm); 12 (57%) were Spetzler-Martin Grade IV or V. Clinical follow-up was available in 20 of 21 cases; radiological follow-up was available in 19 of 21 cases (mean duration of follow-up 3.6 years). Forty-three embolization procedures were performed; 8 embolization-related complications occurred, leading to transient neurological deficits in 5 patients (24%), minor permanent neurological deficits in 3 patients (14%), and major permanent neurological deficits in none (0%). Twenty-one SRS procedures were performed; 1 radiation-induced complication occurred (5%), leading to a permanent minor neurological deficit. Of the 20 patients with clinical follow-up, none experienced cerebral hemorrhage. In the 19 patients with radiological follow-up, AVM obliteration was confirmed by catheter angiography in 13, MR angiography in 2, and CT angiography in 1. Residual nidus was found in 3 patients. In patients with follow-up catheter angiography, the AVM obliteration rate was 81% (13 of 16 cases).

Conclusions

Staged endovascular embolization followed by SRS provides an effective means of treating large AVMs not amenable to standard surgical or SRS treatment. The outcomes and complication rates reported in this series compare favorably to the results of other reported therapeutic strategies for this very challenging patient population.

Full access

Chad W. Washington, Colin P. Derdeyn, Rajat Dhar, Eric J. Arias, Michael R. Chicoine, DeWitte T. Cross, Ralph G. Dacey Jr., Byung Hee Han, Christopher J. Moran, Keith M. Rich, Ananth K. Vellimana and Gregory J. Zipfel

OBJECT

Studies show that phosphodiesterase-V (PDE-V) inhibition reduces cerebral vasospasm (CVS) and improves outcomes after experimental subarachnoid hemorrhage (SAH). This study was performed to investigate the safety and effect of sildenafil (an FDA-approved PDE-V inhibitor) on angiographic CVS in SAH patients.

METHODS

A2-phase, prospective, nonrandomized, human trial was implemented. Subarachnoid hemorrhage patients underwent angiography on Day 7 to assess for CVS. Those with CVS were given 10 mg of intravenous sildenafil in the first phase of the study and 30 mg in the second phase. In both, angiography was repeated 30 minutes after infusion. Safety was assessed by monitoring neurological examination findings and vital signs and for the development of adverse reactions. For angiographic assessment, in a blinded fashion, pre- and post-sildenafil images were graded as “improvement” or “no improvement” in CVS. Unblinded measurements were made between pre- and post-sildenafil angiograms.

RESULTS

Twelve patients received sildenafil; 5 patients received 10 mg and 7 received 30 mg. There were no adverse reactions. There was no adverse effect on heart rate or intracranial pressure. Sildenafil resulted in a transient decline in mean arterial pressure, an average of 17% with a return to baseline in an average of 18 minutes. Eight patients (67%) were found to have a positive angiographic response to sildenafil, 3 (60%) in the low-dose group and 5 (71%) in the high-dose group. The largest degree of vessel dilation was an average of 0.8 mm (range 0–2.1 mm). This corresponded to an average percentage increase in vessel diameter of 62% (range 0%–200%).

CONCLUSIONS

The results from this Phase I safety and proof-of-concept trial assessing the use of intravenous sildenafil in patients with CVS show that sildenafil is safe and well tolerated in the setting of SAH. Furthermore, the angiographic data suggest that sildenafil has a positive impact on human CVS.

Restricted access

Peter T. Sylvester, Christopher J. Moran, Colin P. Derdeyn, DeWitte T. Cross, Ralph G. Dacey, Gregory J. Zipfel, Albert H. Kim, Ravi Uppaluri, Bruce H. Haughey, Rene Tempelhoff, Keith M. Rich, John Schneider, Richard A. Chole and Michael R. Chicoine

OBJECTIVE

Internal carotid artery (ICA) injury is a rare but severe complication of endonasal surgery. The authors describe their endovascular experience managing ICA injuries after transsphenoidal surgery; they review and summarize the current literature regarding endovascular techniques; and they propose a treatment algorithm based on the available evidence.

METHODS

A retrospective review of 576 transsphenoidal pituitary adenoma resections was performed. Cases of ICA injury occurring at our institution and transfers from other hospitals were evaluated. Endovascular treatments for ICA injury reported in the literature were also reviewed and summarized.

RESULTS

Seven cases were identified from the institutional cohort (mean age 46.3 years, mean follow-up 43.4 months [1–107 months]) that received endovascular treatment for ICA injury. Five injuries occurred at our institution (5 [0.9%] of 576), and 2 injuries occurred at outside hospitals. Three patients underwent ICA sacrifice by coil placement, 2 underwent lesion embolization (coil or stent-assisted coil placement), and 2 underwent endoluminal reconstruction (both with flow diversion devices). Review of the literature identified 98 cases of ICA injury treated with endovascular methods. Of the 105 total cases, 46 patients underwent ICA sacrifice, 28 underwent lesion embolization, and 31 underwent endoluminal reconstruction. Sacrifice of the ICA proved a durable solution in all cases; however, the rate of persistent neurological complications was relatively high (10 [21.7%] of 46). Lesion embolization was primarily performed by coil embolization without stenting (16 cases) and stent-assisted coiling (9 cases). Both techniques had a relatively high rate of at least some technical complication (6 [37.5%] of 16 and 5 [55.6%] of 9, respectively) and major technical complications (i.e., injury, new neurological deficit, or ICA sacrifice) (5 [31.3%] of 16 and 2 [22.2%] of 9, respectively). Endoluminal reconstruction was performed by covered stent (24 cases) and flow diverter (5 cases) placement. Covered stents showed a reasonably high rate of technical complications (10 [41.7%] of 24); however, 8 of these problems were resolved, leaving a small percentage with major technical complications (2 [8.3%] of 24). Flow diverter placement was also well tolerated, with only 1 minor technical complication.

CONCLUSIONS

Endovascular treatments including vessel sacrifice, coil embolization (with or without stent assistance), and endoluminal reconstruction offer a tailored approach to ICA injury management after endonasal surgery. Vessel sacrifice remains the definitive treatment for acute, uncontrolled bleeding; however, vessel preservation techniques should be considered carefully in select patients. Multiple factors including vascular anatomy, injury characteristics, and risk of dual antiplatelet therapy should guide best treatment, but more study is needed (particularly with flow diverters) to refine this decision-making process. Ideally, all endovascular treatment options should be available at institutions performing endonasal surgery.