Impact of admission month and hospital teaching status on outcomes in subarachnoid hemorrhage: evidence against the July effect

Object

The authors sought to identify the presence of a “July effect,” a transient increase in adverse outcomes during July, among a cohort of spontaneous subarachnoid hemorrhage (SAH) admissions recorded in the National Inpatient Sample (NIS).

Methods

The discharge status, admission month, patient demographics, treatment parameters, and hospital characteristics among spontaneous SAH admissions were extracted from the 2001–2008 NIS. Multivariate regression was used to determine whether an unfavorable discharge status and/or in-hospital mortality significantly increased in summer months in a pattern suggestive of a July effect. Additional models were generated to assess the impact of hospital teaching status on these outcomes.

Results

Among 57,663,486 hospital admissions from the 2001–2008 NIS, 52,879 cases of spontaneous SAH (ICD-9-CM 430) were treated at teaching (36,914 cases [70%]) and nonteaching (15,965 cases [30%]) facilities. Regression models failed to reveal a July effect for in-hospital mortality (χ2 = 0.75, p = 1.000) or unfavorable discharges (χ2 = 1.69, p = 0.999) among monthly SAH admissions, although they did suggest a significant reduction in these outcomes (in-hospital mortality, OR = 0.89, p < 0.001; unfavorable discharges, OR = 0.88, p < 0.001) among teaching hospitals as compared with nonteaching hospitals after adjustment for disparities in demographic, treatment, and hospital characteristics.

Conclusions

The discharge disposition among SAH admissions within the NIS was not suggestive of a July effect but did reveal that teaching institutions have significantly lower rates of adverse outcomes when compared with nonteaching hospitals. Note, however, that the origins of this difference related to teaching status remain unclear.

Observer agreement in the assessment of minor and major cerebral aneurysm recurrence

We studied the use of minor and major recurrence classifications with regard to observer variability, which directly affects validity of these terms as outcome measures. Recurrences at the time of a three to six month follow-up angiogram were assessed independently by two experienced observers in 83 cases. Intra- and interobserver concordance is approximately 90% for assessment of minor and major recurrence.

Hospitalization costs for acute ischemic stroke patients treated with intravenous thrombolysis in the United States are substantially higher than medicare payments

BACKGROUND AND PURPOSE

It is important to know the costs for hospitalization for ischemic stroke patients treated with intravenous thrombolysis so that comparisons can be made with payments to hospitals.

METHODS

Using the National Inpatient Sample, we evaluated hospitalization costs for patients treated with intravenous thrombolysis for acute ischemic stroke in the United States from 2001 to 2008. Cost data were correlated with demographics and clinical outcome.

RESULTS

Intravenous thrombolysis for acute ischemic stroke was received by 63 472 patients; 24 094 patients were younger than age 65 years and 40 780 patients were 65 years or older. Median hospital costs in 2008 dollars were $14 102 (interquartile range, $9987-$20 819) for patients with good outcome, $18 856 (interquartile range, $13 145-$30 423) for patients with severe disability, and $19 129 (interquartile range, $11 966-$30 781) for patients with in-hospital mortality. Average 2008 Medicare payments were $10 098 for intravenous thrombolysis without complication and $13 835 for intravenous thrombolysis with major complication.

CONCLUSIONS

Hospitalization costs for patients treated with intravenous thrombolysis are substantially higher than Medicare payments.

Endovascular treatment of ruptured paraclinoid aneurysms: results, complications, and follow-up

BACKGROUND AND PURPOSE

Paraclinoid aneurysms are an uncommon cause of aneurysmal SAH, and their treatment is challenging. To assess the effectiveness and safety of endovascular treatment of ruptured paraclinoid aneurysms, we performed a retrospective analysis of 33 patients.

MATERIALS AND METHODS

Clinical and radiologic information on 33 patients undergoing endovascular therapy between 1999 and 2010 was retrospectively reviewed. Angiographic results were evaluated with the modified Raymond grading system, whereas clinical outcomes were evaluated with the mRS scale.

RESULTS

Seventeen (52%) aneurysms were classified as clinoid segment aneurysms, and 16 (48%), as ophthalmic segment aneurysms. Twenty-six (79%) aneurysms were small, 6 (18%) were large, 1 was (3%) giant, and 39% were wide-neck. Coiling was done with balloon assistance in 36% of cases and stent-assistance in 6%. Technical complications occurred in 1 patient, contributing to death. Early clinical complications causing permanent disability occurred in 3% of cases. One patient (3%) had fatal rebleeding 18 days after treatment. Overall, procedure-related morbidity and mortality were, respectively, 3% and 6%. Complete occlusion of the aneurysm was achieved in 36% of patients after initial treatment and in 65% during follow-up (average, 29.3 months). Seven patients had recurrences requiring retreatment (30%). Clinical outcome (average, 32.9 months) was good in 75% of patients and poor in 25%. No delayed complications related to treatment and/or the aneurysm occurred.

CONCLUSIONS

Ruptured paraclinoid aneurysms are challenging lesions from an endovascular and surgical point of view. Despite the high rate of recurrences, good clinical results and protection against rebleeding can be achieved with current endovascular techniques.

Racial and ethnic disparities in the use of intravenous recombinant tissue plasminogen activator and outcomes for acute ischemic stroke

Racial and ethnic disparities in acute stroke care in the United States have been previously reported. This study investigated possible racial and ethnic disparities in the administration and outcome of recombinant tissue plasminogen activator (rtPA) therapy for acute ischemic stroke in whites, blacks, Hispanics, and Asian/Pacific Islanders. Using the National Inpatient Sample for 2001-2008, we selected patients with a primary diagnosis of acute ischemic stroke who received treatment with rtPA. Patient data were stratified by race (white, black, Hispanic, and Asian/Pacific Islander). We analyzed the association of patient race on rtPA utilization rate, in-hospital morbidity (ie, discharge to long-term facility), intracranial hemorrhage (ICH) rate, and in-hospital mortality. We performed a multivariate logistic regression analysis to determine independent predictors of poor outcomes. White patients had a higher rate of tPA utilization than black and Hispanic patients (2.3% vs 1.8% and 2.0%, respectively; P < .0001 for both groups). There was no difference in the rate of tPA utilization between whites and Asian/Pacific Islanders (2.3% vs 2.2% P = .07). Multivariate analysis of morbidity, mortality, and ICH rates found that Asian/Pacific Islanders had significantly higher rates of mortality (odds ratio, 1.22, 95% confidence interval, 1.03-1.44; P = .02) and ICH (odds ratio, 2.01; 95% confidence interval, 1.91-2.11; P < .0001) compared with whites. rtPA utilization was greater in white and Asian/Pacific Islander patients than in black and Hispanic patients. Asian/Pacific Islander race was associated with increased risk of ICH and mortality after rtPA administration.

Estimating the proportion of intracranial aneurysms likely to be amenable to treatment with the pipeline embolization device

OBJECTIVE

A study was undertaken to estimate the fraction of intracranial aneurysms that might be amenable to treatment with the pipeline embolization device (PED), a current flow diverter device, and to determine the types of aneurysms that are probably not amenable to treatment with this device.

METHODS

A retrospective analysis of 200 consecutive intracranial aneurysms as seen on three-dimensional rotational angiography images was conducted. Based on aneurysm and parent artery morphology, four independent observers experienced in the use of the PED judged the likelihood that a given aneurysm could theoretically be treated with one or more PED using a 5-point scale: grades 1 and 2 indicated amenability to treatment with multiple devices; grade 3 indicated amenability to treatment with one device; and grades 4 and 5 indicated the aneurysm would not be amenable to treatment with the PED. Aneurysms were analyzed on the basis of anatomical factors only. Rupture status was not considered. Interobserver agreement was determined.

RESULTS

94 of 200 aneurysms (47%) were judged to be likely to be amenable to treatment with the PED; 50 cases (25%) were judged to be amenable to the use of multiple overlapping devices while, in 44 cases (22%), coverage with a single device was preferred. There was a significant relationship between the location of the aneurysm and the grade of the aneurysm (p<0.0001).

CONCLUSION

On the basis of anatomical configuration, nearly half of the aneurysms in this study were likely to be amenable to treatment with the PED.

Increasing treatment of ruptured cerebral aneurysms at high-volume centers in the United States

Object

Evidence of better outcomes in patients with aneurysmal subarachnoid hemorrhage treated at higher-volume centers might be expected to result in more of these patients being referred to such centers. The authors evaluated the US National Inpatient Sample for the years 2001 to 2008 for trends in patient admissions for the treatment of ruptured aneurysms at high- and low-volume centers.

Methods

The authors determined the number of ruptured aneurysms treated with clipping or coiling annually at low-volume (≤ 20 patients/year) and high-volume (> 20 patients/year) centers and also counted the number of high- and low-volume centers performing each treatment. Hospitalizations for clipping or coiling ruptured aneurysms were identified by cross-matching International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes for the diagnosis of a ruptured aneurysm (ICD-9-CM 430) with procedure codes for clipping (ICD-9-CM 39.51) or coiling (ICD-9-CM 39.52, 39.79, or 39.72) cerebral aneurysms.

Results

In 2001, 31% (435 of 1392) of the patients who underwent clipping and 0% (0 of 122 patients) of those who underwent coiling did so at high-volume centers, whereas in 2008 these numbers increased to 62% (627 of 1016) and 68% (917 of 1351) of patients, respectively. For clipping procedures, the number of low-volume centers significantly declined from 177 in 2001 to 85 in 2008, whereas the number of high-volume centers remained constant at 13–15. For coiling procedures, the number of low-volume centers decreased from 62 in 2001 to 54 in 2008, whereas the number of high-volume centers substantially increased from 0 in 2001 to 16 in 2005 and remained constant thereafter.

Conclusions

The treatment of ruptured cerebral aneurysms increasingly occurs at high-volume centers in the US. This trend is favorable given that better outcomes are associated with the treatment of these lesions at high-volume centers.

Hospitalization Costs for Patients With Acute Ischemic Stroke Treated With Endovascular Embolectomy in the United States

Background and Purpose—

It is important to know the costs of hospitalization for patients undergoing endovascular embolectomy so that comparisons can be made with payments to hospitals.

Methods—

Using the National Inpatient Sample, we evaluated the costs of hospitalization for patients treated with endovascular embolectomy in the United States from 2006 to 2008. The primary end point examined in this study was total hospital costs, and these were correlated with clinical outcome.

Results—

A total of 3864 patients received endovascular embolectomy. A total of 1649 patients were <65 years old and 2205 patients were ≥65 years old. Median hospital costs in 2008 dollars were $36 999 (interquartile range, $26 662–$56 405) for patients with good outcome, $50 628 (interquartile range, $33 135–$76 063) for patients with severe disability, and $35 109 (interquartile range, $25 053–$62 621) for patients with mortality.

Conclusions—

Hospitalization costs for patients treated with endovascular embolectomy are rather high, probably due to the serious nature of their illness. Medicare payments have not been adequate reimbursement for these hospitalizations.

Hospitalization costs for endovascular and surgical treatment of unruptured cerebral aneurysms in the United States are substantially higher than medicare payments

BACKGROUND AND PURPOSE

Both endovascular and surgical options are available for treatment of unruptured cerebral aneurysms. We conducted a study to determine the costs versus Medicare reimbursement for hospitalization of these patients, which is important information for understanding the economic impact of these patients on hospitals.

MATERIALS AND METHODS

Using the NIS, we identified hospitalizations for clipping and coiling of unruptured cerebral aneurysms from 2001 to 2008 by cross-matching ICD-9 codes for diagnosis of unruptured aneurysm with procedure codes for clipping or coiling of cerebral aneurysms and excluding all patients with subarachnoid hemorrhage and intracerebral hemorrhage. Hospital costs for 2008 were correlated with age, sex, and discharge status and compared with Medicare payments.

RESULTS

Costs of both clipping and coiling have increased from 2001 to 2008. The median 2008 hospital costs were $23,574 (IQR, $18,233-$29,941) for clipping and $25,734 (IQR, $17,436-$35,846) for coiling without complications, which were higher than the average Medicare payment of $12,599. The median hospital costs were $36,188 (IQR, $21,831-$55,308) for clipping and $40,502 (IQR, $24,289-$50,108) for coiling treatments complicated by major morbidity and $68,165 (IQR, $32,972-$100,211) for clipping and $56,020 for coiling treatments complicated by mortality, which were higher than the average Medicare payment for patients with major complications and comorbidities of $22,946. In multivariate analysis, female sex was associated with higher costs for coiling (P = .02), and poor discharge status was associated with higher costs for both clipping (P < .001) and coiling (P < .001).

CONCLUSIONS

Hospitalization costs for patients undergoing clipping and coiling of unruptured cerebral aneurysms are substantially higher than Medicare payments.

Mortality in the vertebroplasty population

BACKGROUND AND PURPOSE

Vertebroplasty is an effective treatment for painful compression fractures refractory to conservative management. Because there are limited data regarding the survival characteristics of this patient population, we compared the survival of a treated with an untreated vertebral fracture cohort to determine whether vertebroplasty affects mortality rates.

MATERIALS AND METHODS

The survival of a treated cohort, comprising 524 vertebroplasty recipients with refractory osteoporotic vertebral compression fractures, was compared with a separate historical cohort of 589 subjects with fractures not treated by vertebroplasty who were identified from the Rochester Epidemiology Project. Mortality was compared between cohorts by using Cox proportional hazards models adjusting for age, sex, and Charlson indices of comorbidity. Mortality was also correlated with pre-, peri-, and postprocedural clinical metrics (eg, cement volume use, RDQ score, analog pain scales, frequency of narcotic use, and improvement in mobility) within the treated cohort.

RESULTS

Vertebroplasty recipients demonstrated 77% of the survival expected for individuals of similar age, ethnicity, and sex within the US population. Compared with individuals with both symptomatic and asymptomatic untreated vertebral fractures, vertebroplasty recipients retained a 17% greater mortality risk. However, compared with symptomatic untreated vertebral fractures, vertebroplasty recipients had no increased mortality following adjustment for differences in age, sex, and comorbidity (HR, 1.02; 95% CI, 0.82-1.25). In addition, no clinical metrics used to assess the efficacy of vertebroplasty were predictive of survival.

CONCLUSIONS

Vertebroplasty recipients have mortality rates similar to those of individuals with untreated symptomatic fractures but have worse mortality compared with those with asymptomatic vertebral fractures.

Intracranial Hemorrhage Is Much More Common After Carotid Stenting Than After Endarterectomy

Background and Purpose—

Intracranial hemorrhage (ICH) is a rare and devastating complication of carotid revascularization. We sought to determine the prevalence of, type of, and risk factors associated with ICH among recipients of carotid endarterectomy (CEA) and carotid angioplasty and stenting (CAS) within the National Inpatient Sample (NIS).

Methods—

Postoperative cases of ICH after CEA (International Classification of Disease 9 th edition [ICD-9]: 38.12) or CAS (ICD-9: 00.63) were retrieved from the 2001 to 2008 NIS. Clinical presentation (asymptomatic versus symptomatic), discharge status, in-hospital mortality, demographics, and hospital characteristics were extracted from NIS data. Charlson indices of comorbidity were determined based on ICD-9 and clinical classification software codes. Multivariate regression was used to determine the impact of revascularization procedure type and symptom status on adverse outcomes, including ICH, in-hospital mortality, and unfavorable discharge status.

Results—

Among 57 663 486 NIS hospital admissions, 215 012 CEA and 13 884 CAS procedures were performed. Symptomatic presentations represented the minority of CEA (N=10 049; 5%) and CAS cases (N=1251; 10%). ICH occurred significantly more frequently after CAS than CEA in both symptomatic (4.4% versus 0.8%; P <0.0001) and asymptomatic presentations (0.5% versus 0.06%; P <0.0001). Multivariate regression suggested that symptomatic presentations (versus asymptomatic) and CAS procedures (versus CEA) were both independently predictive of 6-fold to 7-fold increases in the frequency of postoperative ICH. ICH was independently predictive in a 30-fold increased risk of mortality before discharge.

Conclusions—

CAS procedures are associated with elevated adverse outcomes, including ICH, in-hospital death, and unfavorable discharges, especially among symptomatic presentations.

Stenting versus aggressive medical therapy for intracranial arterial stenosis

BACKGROUND

Atherosclerotic intracranial arterial stenosis is an important cause of stroke that is increasingly being treated with percutaneous transluminal angioplasty and stenting (PTAS) to prevent recurrent stroke. However, PTAS has not been compared with medical management in a randomized trial.

METHODS

We randomly assigned patients who had a recent transient ischemic attack or stroke attributed to stenosis of 70 to 99% of the diameter of a major intracranial artery to aggressive medical management alone or aggressive medical management plus PTAS with the use of the Wingspan stent system. The primary end point was stroke or death within 30 days after enrollment or after a revascularization procedure for the qualifying lesion during the follow-up period or stroke in the territory of the qualifying artery beyond 30 days.

RESULTS

Enrollment was stopped after 451 patients underwent randomization, because the 30-day rate of stroke or death was 14.7% in the PTAS group (nonfatal stroke, 12.5%; fatal stroke, 2.2%) and 5.8% in the medical-management group (nonfatal stroke, 5.3%; non-stroke-related death, 0.4%) (P=0.002). Beyond 30 days, stroke in the same territory occurred in 13 patients in each group. Currently, the mean duration of follow-up, which is ongoing, is 11.9 months. The probability of the occurrence of a primary end-point event over time differed significantly between the two treatment groups (P=0.009), with 1-year rates of the primary end point of 20.0% in the PTAS group and 12.2% in the medical-management group.

CONCLUSIONS

In patients with intracranial arterial stenosis, aggressive medical management was superior to PTAS with the use of the Wingspan stent system, both because the risk of early stroke after PTAS was high and because the risk of stroke with aggressive medical therapy alone was lower than expected. (Funded by the National Institute of Neurological Disorders and Stroke and others; SAMMPRIS ClinicalTrials.gov number, NCT00576693.).

Trends of inpatient spine augmentation: 2001-2008

BACKGROUND AND PURPOSE

Vertebroplasty and kyphoplasty are 2 minimally invasive spine augmentation procedures currently used in the management of vertebral compression fractures. Our aim was to examine the NIS data base to identify trends in spine augmentation procedures over time.

MATERIALS AND METHODS

Patients were identified from the NIS data base by using primary diagnosis codes (ICD-9-pathologic vertebral fracture, 733.13) and procedures codes (ICD-9-other repair of bone, 78.49; vertebroplasty, 81.65; kyphoplasty, 81.66). Means and their corresponding standard errors were compared for statistically significant differences by using the Z-test.

RESULTS

Between 2001 and 2008, >240 000 inpatient spine augmentations were performed in the United States. From 2001 to 2008, there was a 741% increase in the number of hospital discharges for patients who underwent a spine augmentation, but the year-to-year rate of increase has been declining since 2001. From 2004 to 2008, >50 000 inpatient verterbroplasties and >152 000 inpatient kyphoplasties were identified. Compared with vertebroplasty, kyphoplasty patients were less often admitted from the emergency department (33% versus 56%, P < .001), had shorter postaugmentation hospital stays (2.3 versus 3.1 days, P < .001), had fewer comorbidities at presentation (1.4 versus 1.6, P < .01), and were less likely to be discharged to a long-term facility (28% versus 43%, P < .001).

CONCLUSIONS

Significant differences were noted in multiple comparisons between vertebroplasty and kyphoplasty, including length of hospital stay and discharges to long-term facilities. However, these findings may simply reflect differences in practice patterns rather than real differences in efficacy between the procedures.

Endovascular treatment of middle cerebral artery aneurysms: a systematic review and single-center series

BACKGROUND

Middle cerebral artery (MCA) aneurysms are often considered unsuitable for endovascular coiling because of unfavorable morphological features. With improvements in endovascular techniques, several series have detailed the results and complications of endovascular treatment of MCA aneurysms.

OBJECTIVE

We performed a systematic review of published series on endovascular treatment of MCA aneurysms including our experience.

METHODS

We conducted a computerized MEDLINE search of the literature on endovascular treatment of MCA aneurysms. Only studies examining a consecutive case series of MCA aneurysms were included. We then extracted information regarding intraprocedural complications, procedural mortality and morbidity, immediate and long-term angiographic outcomes, and re-treatment rate. Analysis was done including 40 MCA aneurysms treated at our institution.

RESULTS

Twelve studies including our institution's consecutive case series were included. Approximately 50% of the aneurysms presented as ruptured. Intraprocedural rupture rate in unruptured aneurysms was 1.7% (95% confidence interval [CI] = 0.7%-3.6%) compared with 4.8% (95% CI = 3.1%-7.4%) for ruptured aneurysms (P = .02). The risk of early postprocedural hemorrhage was 1.1% (95% CI = 0.5%-2.5%) for ruptured aneurysms. Overall procedure-related permanent morbidity and mortality were 5.1% and 6.0% for unruptured and ruptured aneurysms, respectively. The overall rate of complete or near-complete obliteration at angiographic follow-up was 82.4%.

CONCLUSION

Endovascular treatment of MCA aneurysms is feasible and effective in selected cases. The combined periprocedural mortality and morbidity is not negligible (5.1%) and the overall rate of complete or near-complete angiographic obliteration at follow-up approaches 82%.

Onyx Embolization of Extradural Spinal Arteriovenous Malformations With Intradural Venous Drainage

BACKGROUND:

Extradural arteriovenous malformations (AVMs) are uncommon vascular malformations of the spine. They are characterized by an arteriovenous communication (localized in the paraspinal soft tissues and the epidural venous plexus) that may have retrograde intradural venous drainage. Surgical treatment of extradural AVMs can be challenging because of the common location ventral to the dural sac and the presence of arterialized venous lakes.

OBJECTIVE:

To assess the effectiveness of embolization with a liquid embolic material (Onyx; ev3 Inc, Irvine, California) in 7 consecutive patients with extradural spinal AVMs and intradural venous drainage.

METHODS:

We retrospectively collected information regarding patient characteristics, clinical presentation, symptom duration, diagnostic imaging, treatment, complications, and clinical and radiological follow-up.

RESULTS:

Patients were 5 men and 2 women (mean age, 66 years; range, 45-76 years). Symptom duration varied from 2 months to 6 years. Six patients underwent embolization of the AVM as the primary treatment; 1 patient was treated after attempted surgery. Complete obliteration was demonstrated in each patient on completion angiography and was confirmed during follow-up in 6. Three patients had resolution of their preembolization symptoms. Three patients had improvement but not complete resolution of their motor deficits. In 1 patient, the AVM was an incidental finding during an investigation for chronic low-back pain; symptoms were not thought to be related to the AVM, and symptoms were not ameliorated by successful embolization.

CONCLUSION:

Our early experience with these uncommon lesions suggests that Onyx embolization is a valuable and effective strategy for extradural spinal AVMs and intradural venous drainage.

Flow Diversion for Intracranial Aneurysms

The introduction of flow diverters for treatment of intracranial aneurysms represents a major paradigm shift in the treatment of these lesions. The theoretical hallmark of flow diverters is the treatment of the diseased segment harboring the aneurysm instead of treating the aneurysm itself. Flow diverters are designed to induce disruption of flow near the aneurysm neck while preserving flow into parent vessel and adjacent branches. After flow diversion, intra-aneurysmal thrombosis occurs, followed by shrinkage of the aneurysmal sac as the thrombus organizes and retracts. Preliminary clinical series document effective treatment of wide-neck and/or large and giant aneurysms with acceptable complication rates. However, several questions remain unanswered related to the incidence and mechanisms of aneurysm rupture after treatment with flow diverters, fate of small perforating vessels, and long-term patency rates.

Intercavernous sinus dural arteriovenous fistula successfully treated with transvenous embolization. a case report

The venous sinuses commonly found in the margins of the diaphragm and sella are venous interconnections between the bilateral cavernous dural sinuses and are termed intercavernous communications or intercavernous sinuses. They form a venous ring, a single "circular sinus" that extends throughout the skull base. We report the first case to our knowledge of an intercavernous sinus fistula. We emphasize the importance of thorough knowledge of lesion characteristics before considering any interventional procedure.An 84-year-old woman presented with alarming progressive orbital symptoms for one month affecting her left eye. A cerebral angiogram showed an intercavernous sinus fistula supplied by internal and external carotid arterial branches.Transvenous embolization through retrograde catheterization of the right inferior petrosal sinus allowed complete coil occlusion of the lesion. Cerebral angiography confirmed the absence of residual blood flow through the fistula.This report represents the first case of an intercavernous sinus dural arteriovenous fistula successfully treated with transvenous embolization. A detailed awareness of the regional anatomy is essential for treatment approach and favorable outcomes.

Stent-assisted coiling in acutely ruptured intracranial aneurysms: a qualitative, systematic review of the literature

BACKGROUND AND PURPOSE

The use of stents for treatment of morphologically unfavorable, acutely ruptured aneurysms is avoided by most operators because of concerns about the risk of using dual antiplatelet therapy in the setting of acute SAH. Our aim was to review the literature regarding stent-assisted coil embolization of acutely ruptured intracranial aneurysms to determine the safety and efficacy of this treatment option.

MATERIALS AND METHODS

Articles including ≥5 patients with ruptured aneurysms who were treated acutely with stent-assisted coiling or uncovered stent placement alone were identified. Data on clinical presentation, technical success, surgical crossover, intracranial complications, and clinical outcome were evaluated.

RESULTS

A total of 17 articles were identified reporting 339 patients who met inclusion criteria. Among 212 patients with available data, technical success was noted in 198 (93%) patients. Three hundred twenty-six (96%) of 339 patients received both heparin during the procedure and dual-antiplatelet therapy during or immediately postprocedure. One hundred thirty (63%) of 207 aneurysms were completely occluded. Six (2%) of 339 patients required surgical crossover, usually for failure in stent placement or for intraprocedural aneurysm rupture. Clinically significant intracranial hemorrhagic complications occurred in 27 (8%) of 339 patients, including 9 (10%) of 90 patients known to have EVDs who had ventricular drain-related hemorrhages. Clinically significant thromboembolic events occurred in 16 (6%) of 288 patients. Sixty-seven percent of patients had favorable clinical outcomes, 14% had poor outcomes, and 19% died.

CONCLUSIONS

Stent-assisted coiling in ruptured aneurysms can be performed with high degrees of technical success, but adverse events appear more common and clinical outcomes are likely worse than those achieved without stent assistance. Thromboembolic complications appear reasonably well-controlled. Reported EVD-related hemorrhagic complications were uncommon, though the total number of EVDs placed was unknown.

Better outcomes with treatment by coiling relative to clipping of unruptured intracranial aneurysms in the United States, 2001-2008

BACKGROUND AND PURPOSE

Endovascular therapy has increasingly become an acceptable option for treatment of unruptured aneurysms. To better understand the recent trends in the use of and outcomes related to coiling compared with clipping for unruptured aneurysms in the United States, we evaluated the NIS.

MATERIALS AND METHODS

Hospitalizations for clipping or coiling of unruptured cerebral aneurysms from 2001 to 2008 were identified by cross-matching ICD codes for the diagnosis of unruptured aneurysm (437.3) with procedural codes for clipping (39.51) or coiling (39.52, 39.79, or 39.72) of cerebral aneurysms and excluding all patients with a diagnosis of subarachnoid hemorrhage (430) and intracerebral hemorrhage (431). Mortality and discharge to a long-term facility were evaluated for both clipping and coiling patient populations.

RESULTS

The fraction of unruptured aneurysms treated with coiling increased from 20% in 2001 to 63% in 2008. For surgical clipping, the percentage of patients discharged to long-term facilities was 14.0% (4184/29,918) compared with 4.9% (1655/34,125) of coiled patients (P < .0001). Clipped patients also had a higher mortality rate because 344 (1.2%) clipped patients died compared with 215 (0.6%) coiled patients (P < .0001). Between 2001 and 2008, the overall number of adverse outcomes from treatment had decreased from 14.8% to 7.6%.

CONCLUSIONS

The use of endovascular coiling relative to surgical clipping of unruptured intracranial aneurysms is associated with decreasing periprocedural morbidity and mortality among patients treated in the United States from 2001 to 2008.

Patient outcomes are better for unruptured cerebral aneurysms treated at centers that preferentially treat with endovascular coiling: a study of the national inpatient sample 2001-2007

BACKGROUND AND PURPOSE

Practice patterns vary widely among centers with regard to the treatment of unruptured aneurysms. The purpose of the current study was to correlate outcome data with practice patterns, specifically the proportion of unruptured aneurysms treated with neurosurgical clipping versus endovascular coiling.

MATERIALS AND METHODS

Using the NIS, we evaluated outcomes of patients treated for unruptured aneurysms in the United States from 2001 to 2007. Hospitalizations for clipping or coiling of unruptured cerebral aneurysms were identified by cross-matching ICD codes for diagnosis of unruptured aneurysm with procedure codes for clipping or coiling of cerebral aneurysms. Mortality and morbidity, measured as "discharge to long-term facility," were evaluated in relation to the fraction of cases treated with coils versus clipping as well as the annual number of unruptured aneurysms treated by individual hospitals and individual physicians.

RESULTS

Markedly lower morbidity (P < .0001) and mortality (P = .0015) were noted in centers that coiled a higher percentage of aneurysms compared with the proportion of aneurysms clipped. Multivariate analysis showed that greater annual numbers of aneurysms treated by individual practitioners were significantly related to decreased morbidity (OR = 0.98, P < .0001), while the association between morbidity and the annual number of aneurysms treated by hospitals was not significant (OR = 1.00, P = .89).

CONCLUSIONS

Centers that treated a higher percentage of unruptured aneurysms with coiling compared with clipping achieved markedly lower rates of morbidity and mortality. Our results also confirm that treatment by high-volume practitioners is associated with decreased morbidity.

Patient outcomes with endovascular embolectomy therapy for acute ischemic stroke: a study of the national inpatient sample: 2006 to 2008

BACKGROUND AND PURPOSE

Maturing techniques have spurred widespread implementation of endovascular embolectomy therapy for ischemic stroke. We evaluated a large administrative database to determine outcomes in patients treated with endovascular embolectomy in the general population.

METHODS

Using the National Inpatient Sample, we evaluated outcomes of patients treated for acute ischemic stroke in the United States from 2006 to 2008. Patients who had an ischemic stroke and underwent endovascular clot retrieval were identified. Morbidity, defined as "discharge to long-term facility," and mortality were evaluated as a function of patient age and of concomitant thrombolytic agent administration.

RESULTS

For 2006 to 2008, a total of 3864 patients received endovascular clot retrieval with 266 (6.9%) patients in 2006, 800 (20.7) patients in 2007, and 2798 (72.4%) patients in 2008. The discharge to a long-term facility rate was 51.3% (1983 of 3864). The in-hospital mortality rate was 24.3% (940 of 3864). For patients <65 years old, the rate of in-hospital death was 17.1% (283 of 1658) as compared with a rate of 29.7% (656 of 2206) for patients ≥65 years old (P<0.0001). The rate of discharge to a long-term facility was 47.6% (789 of 1658) for patients <65 years old and 54.1% (1193 of 2206) for patients ≥65 years old (P<0.0001). The rate of intracranial hemorrhage was 15.5% without concomitant thrombolysis and 20.0% with concomitant thrombolysis (P=0.0009).

CONCLUSIONS

Rates of morbidity and mortality remain high for patients with acute stroke, even in the setting of endovascular embolectomy. Advanced age portends a worse outcome and patients treated with concomitant use of thrombolytic agent had higher rates of intracranial hemorrhage than those without such therapy.

Risk of cerebral angiography in patients with symptomatic intracranial atherosclerotic stenosis

BACKGROUND

A well-defined rate of adverse events following cerebral angiography in patients with symptomatic intracranial atherosclerosis would be useful to physicians making decisions regarding imaging and treatment of these patients. We report the adverse events associated with angiography in patients who underwent single-vessel cerebral angiography as part of the study protocol in the Warfarin-Aspirin for Symptomatic Intracranial Arterial Stenosis trial.

METHODS

Single-vessel cerebral angiography was performed to specifically define the degree of stenosis in 196 patients suspected of having intracranial atherosclerotic stenosis on noninvasive tests. Adverse events that occurred within 24 h of cerebral angiography were reported by the sites performing the angiography.

RESULTS

Overall, neurological adverse events occurred in 4 patients (2.0%; 95% CI: 0.6-5.1%), and nonneurological adverse events occurred in 12 patients (6.1%; 95% CI: 3.2-10.5%). All of the neurological adverse events were transient.

CONCLUSIONS

The risk of permanent neurological adverse events associated with single-vessel cerebral angiography in patients with symptomatic intracranial atherosclerosis is relatively low. The quantification of the risk of cerebral angiography in patients with intracranial atherosclerosis provides useful information to consider when evaluating noninvasive imaging techniques for their relative value.

Effect of age on outcomes of treatment of unruptured cerebral aneurysms: a study of the National Inpatient Sample 2001-2008

BACKGROUND AND PURPOSE

Age might differentially affect outcomes in patients treated for unruptured cerebral aneurysms with surgical clipping versus endovascular coil therapy. We evaluated a large administrative database to determine the effect of age on outcomes in patients treated for unruptured cerebral aneurysm.

METHODS

Using the National Inpatient Sample, we evaluated morbidity (discharge to long-term facility) and mortality of patients undergoing clipping or coiling of unruptured cerebral aneurysms in the United States between 2001 and 2008. Outcomes were evaluated in relation to four age strata: younger than 50 years; 50 to 64 years; 65 to 79 years; and patients 80 years or older.

RESULTS

Patients younger than 50 years old undergoing coiling had significantly lower morbidity rates when compared to patients who underwent clipping (3.5% versus 8.1%; P<0.0001), but no difference in mortality (0.6% versus 0.6%; P=0.72). Patients between 50 and 64 years old undergoing coiling had significantly decreased morbidity (4.0% versus 13.7%; P<0.0001) and mortality (0.5% versus 1.1%; P<0.0001) when compared to patients who underwent clipping. Coiled patients 65 to 79 years old had lower morbidity (6.9% versus 26.8%; P<0.0001) and mortality (0.8% versus 2.0%; P<0.0001) compared to patients who underwent clipping. Patients aged 80 years or older undergoing coiling also had lower morbidity (9.8% versus 33.5%; P<0.0001) and mortality (2.4% versus 21.4%; P<0.0001) when compared to patients who have undergone clipping.

CONCLUSIONS

Patients treated with endovascular coiling have significantly less morbidity and mortality than those treated with surgical clipping, and these differences become more pronounced with age.

Collaterals dramatically alter stroke risk in intracranial atherosclerosis

OBJECTIVE

Stroke risk due to intracranial atherosclerosis increases with degree of arterial stenosis. We evaluated the previously unexplored role of collaterals in modifying stroke risk in intracranial atherosclerosis and impact on subsequent stroke characteristics.

METHODS

Collateral flow was graded in blind fashion on 287 of 569 baseline angiograms (stenoses of 50-99% and adequate collateral views) in the Warfarin--Aspirin Symptomatic Intracranial Disease (WASID) trial. Statistical models predicted stroke in the symptomatic arterial territory based on collateral flow grade, percentage of stenosis, and previously demonstrated independent covariates.

RESULTS

Across all stenoses, extent of collaterals was a predictor for subsequent stroke in the symptomatic arterial territory (hazard ratio [HR] none vs good, 1.14; 95% confidence interval [CI], 0.39-3.30; poor vs good, 4.36; 95% CI, 1.46-13.07; p < 0.0001). For 70 to 99% stenoses, more extensive collaterals diminished risk of subsequent territorial stroke (HR none vs good, 4.60; 95% CI, 1.03-20.56; poor vs good, 5.90; 95% CI, 1.25-27.81; p = 0.0427). At milder degrees of stenoses (50-69%), presence of collaterals was associated with greater likelihood of subsequent stroke (HR none vs good, 0.18; 95% CI, 0.04-0.82; poor vs good, 1.78; 95% CI, 0.37-8.57; p < 0.0001). In multivariate analyses, extent of collaterals was an independent predictor for subsequent stroke in the symptomatic arterial territory (HR none vs good, 1.62; 95% CI, 0.52-5.11; poor vs good, 4.78; 95% CI, 1.55-14.7; p = 0.0019).

INTERPRETATION

Collateral circulation is a potent determinant of stroke risk in intracranial atherosclerosis, demonstrating a protective role with severe stenoses and identifying more unstable milder stenoses.

Volumetric myelographic magnetic resonance imaging to localize difficult-to-find spinal dural arteriovenous fistulas

Although more prevalent in males in the 6th and 7th decade of life, spinal dural arteriovenous fistulas (SDAVFs) are an uncommon cause of progressive myelopathy. Magnetic resonance imaging and more recently Gd bolus MR angiography have been used to diagnose, radiographically define, and preprocedurally localize the contributing lumbar artery. Three-dimensional myelographic MR imaging sequences have recently been developed for anatomical evaluation of the spinal canal. The authors describe 3 recent cases in which volumetric myelographic MR imaging with a 3D phase-cycled fast imaging employing steady state acquisition (PC-FIESTA) and a 3D constructive interference steady state (CISS) technique were particularly useful not only for documenting an SDAVF, but also for providing localization when CT angiography, MR imaging, MR angiography, and spinal angiography failed to localize the fistula. In a patient harboring an SDAVF at T-4, surgical exploration was performed based on the constellation of findings on the PC-FIESTA images as well as the fact that the spinal segments leading to T-4 were the only ones that the authors were unable to catheterize. In a second patient, who harbored an SDAVF at T-6, after 2 separate angiograms failed to demonstrate the fistula, careful assessment of the CISS images led the authors to focus a third angiogram on the left T-6 intercostal artery and to perform superselective microcatheterization. In a third patient with an SDAVF originating from the lateral sacral branch, the PC-FIESTA sequence demonstrated the arterialized vein extending into the S-1 foramen, leading to a second angiogram and superselective internal iliac injections. The authors concluded that myelographic MR imaging sequences can be useful not only as an aid to diagnosis but also for localization of an SDAVF in complex cases.

Observer agreement regarding the necessity of retreatment of previously coiled recurrent cerebral aneurysms

BACKGROUND AND PURPOSE

The decision regarding whether or not to retreat a previously treated aneurysm not only directly impacts patient care but also serves as a primary outcome measure in numerous, leading randomized controlled trials of modified coils. Our aim was to determine the degree of interobserver variability regarding the need and type of treatment for recurrent aneurysms following coil embolization.

MATERIALS AND METHODS

Twenty-seven previously treated recurrent aneurysms were identified. Five independent readers rated each aneurysm on a 5-point scale: 1, definitely do not retreat; 2, probably do not retreat; 3, unsure; 4, probably retreat; and 5, definitely retreat. The readers noted, in grades 2-5, the type of retreatment preferred, including simple coiling, balloon- or stent-assist coiling, or surgical clipping. Intraobserver agreement κ was calculated. Retreatment recommendations were evaluated between observers by using a Wilcoxon signed rank comparison. Descriptive statistics were performed for categoric treatment-type comparisons.

RESULTS

At least 2- or 3-point differences between 2 readers were present in 17 (63%) and 11 (41%) of 27 cases, respectively. The median κ was 0.27 (range, 0.04-0.43), which indicates fair agreement. Differences between readers varied, with readers 4 and 5 more often recommending retreatment compared with reviewers 1-3 (P < .05). Wide variation was noted in treatment approach, with recommendations for surgical clipping ranging from 2 (7%) to 18 (67%) of 27 cases between readers 1 and 5.

CONCLUSIONS

The current study demonstrates substantial variability among observers not only in whether to retreat a recurrent aneurysm but also how to treat it. These findings suggest that patient management varies widely across treating physicians and also calls into question the use of "retreatment" as an objective end point in clinical trials.

MicroNester coils as an adjunct to endovascular embolization

OBJECTIVES/BACKGROUND

In June 2003, detachable balloons were removed from the US market and were supplanted with coil embolization for parent artery sacrifice in difficult or nonsurgical aneurysms and other vascular pathologies. The current series examines the use of MicroNester pushable coils (Cook Medical, Bloomington, IN) as a low-cost and effective adjunct to detachable coils in the treatment of selected neurovascular pathologies.

METHODS

A retrospective analysis of all patients undergoing neurointerventional procedures from November 2003 through May 2008 was performed to identify patients in whom MicroNester coils were used as part of treatment. Analysis of coil type and number as well as pathology was performed.

RESULTS

MicroNesters were used in 26 cases, of which 21 were for arterial sacrifice--19 for the internal carotid artery and 2 for the vertebral artery. Fourteen were performed for intracranial aneurysms, 3 for pseudoaneurysms, 2 for carotid cavernous fistulae, 1 for a carotid blowout, and 1 for an arteriovenous malformation. Five additional procedures were transvenous, for treatment of dural arterial venous fistulae. The mean number of coils for artery sacrifice was 13, with an average of 10 MicroNesters. For transvenous embolizations, the means were 30 and 6, respectively.

CONCLUSION

MicroNesters are not the coil of choice for most neurointerventional procedures because they are not retrievable. However, when parent artery sacrifice or transvenous occlusion of dural arteriovenous fistulas is the goal, MicroNesters are a relatively inexpensive and equally effective alternative to more expensive, detachable coils and can reduce the procedural costs by $3600 to $6000 for the current series.

Risk factors associated with severity and location of intracranial arterial stenosis

BACKGROUND AND PURPOSE

We sought to determine the vascular risk factors and demographic features associated with the severity and location of intracranial stenosis.

METHODS

Data on patients enrolled in the Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) trial were used for the analyses. Demographic features and vascular risk factors were compared in patients with moderate stenosis (n=336) versus severe stenosis (n=225) and according to the location of intracranial stenosis (middle cerebral, internal carotid, basilar, or vertebral artery).

RESULTS

History of a lipid disorder (77% in severe vs 67% in moderate, P=0.01), metabolic syndrome (63% in severe vs 53% in moderate, P=0.05), and diabetes (43% in severe vs 35% in moderate, P=0.04) were more common in patients with severe intracranial stenosis by univariate analyses. A history of a lipid disorder was independently associated with severe stenosis (odds ratio=1.62; 95% CI, 1.09 to 2.42; P=0.02). The distribution of stenosis location differed among age groups (P=0.0015), sexes (P=0.0001), races (P=0.0243), qualifying events (P=0.0156), diabetes (P=0.0030), coronary artery disease (P=0.0030), and hyperlipidemia (P=0.054). Patients with basilar artery stenoses were older and more likely to have hyperlipidemia. Patients with middle cerebral artery stenoses were more likely to be women and black. Patients with internal carotid artery stenoses were more likely to have diabetes. Patients with vertebral artery stenoses were more likely to have coronary artery disease.

CONCLUSIONS

History of a lipid disorder had the strongest association with severity of intracranial stenosis and should be the target of prevention therapies. Different locations of intracranial stenoses are associated with different vascular risk factors and demographic features, suggesting that there may be a difference in the underlying pathophysiology of stenoses among the intracranial arteries.

The H-index in academic radiology

RATIONALE AND OBJECTIVES

The h index is a recently developed tool to assess the impact of an author's publications. The purpose of this study was to apply and evaluate the h indexes of US academic radiologists.

MATERIALS AND METHODS

Radiology programs that participated in the residency match in 2009 were identified through the National Resident Matching Program's Web site. One third of programs were randomly selected. The academic ranks (instructor, assistant professor, associate professor, professor, or chairperson) of faculty members were determined on the basis of information from the programs' Web sites during October and November 2009. One third of radiologists at each randomly selected institution were randomly selected for detailed analysis. For each radiologist, an automatically computed h index was obtained through the Scopus database. The h index was compared across ranks using analysis of variance. A multivariate logistic regression analysis was also performed to determine the best predictors (number of publications, number of citations, h index, and number of citations per publication) of academic rank.

RESULTS

Sixty hundred eighty-three radiologists from 47 programs were included in this study. The mean h indexes were 1.1 +/- 2.7 for instructors, 2.3 +/- 4.1 for assistant professors, 6.2 +/- 7.2 for associate professors, 12.5 +/- 10.8 for full professors, and 12.0 +/- 9.5 for chairpersons. There was a significant relationship between h index and academic rank (P < .0001). Multivariate logistic regression analysis demonstrated that h index (P < .0001) and number of publications (P < .0001) were the best predictors of academic rank.

CONCLUSION

There exists a significant relationship between h index and academic rank, with h index increasing with academic rank. These results offer a benchmark for comparing a given academic radiologist to national averages.

Posterior reversible encephalopathy syndrome: associated clinical and radiologic findings

OBJECTIVE

To identify and define clinical associations and radiologic findings of posterior reversible encephalopathy syndrome (PRES).

PATIENTS AND METHODS

Patients prospectively diagnosed as having PRES from October 1, 2005, through April 30, 2009, were pooled with retrospectively identified patients admitted from August 1, 1999, through September 30, 2005. We performed a detailed review of clinical information, including demographics, presenting symptoms, medical history, and risk factors. All patients underwent computed tomography of the brain or magnetic resonance imaging. Findings on magnetic resonance imaging were analyzed independently by 2 neuroradiologists.

RESULTS

We identified 120 cases of PRES in 113 patients (mean age, 48 years). Mean peak systolic blood pressure was 199 mm Hg (minimum-maximum, 160-268 mm Hg), and mean peak diastolic blood pressure was 109 mm Hg (minimum-maximum, 60-144 mm Hg). Etiologies of PRES included hypertension (n=69 [61%]), cytotoxic medications (n=21 [19%]), sepsis (n=8 [7%]), preeclampsia or eclampsia (n=7 [6%]), and multiple organ dysfunction (n=1 [1%]). Autoimmune disease was present in 51 patients (45%). Clinical presentations included seizures (n=84 [74%]), encephalopathy (n=32 [28%]), headache (n=29 [26%]), and visual disturbances (n=23 [20%]). In the 115 cases (109 patients) for which magnetic resonance imaging findings were available, the parieto-occipital regions were the most commonly involved (n=108 [94%]), followed by the frontal lobe (n=88 [77%]), temporal lobe (n=74 [64%]), and cerebellum (n=61 [53%]). Cerebellar involvement was significantly more frequent in patients with a history of autoimmunity (P=.008), and patients with sepsis were more likely to have cortical involvement (P<.001).

CONCLUSION

A substantial proportion of patients with PRES have underlying autoimmune conditions that may support endothelial dysfunction as a pathophysiologic mechanism. On brain imaging, the location and severity of vasogenic edema were mostly similar for the different clinical subgroups.

Safety of Early Ambulation After Diagnostic and Therapeutic Neuroendovascular Procedures Without Use of Closure Devices

OBJECTIVE

To evaluate the safety of manual compression and early ambulation after diagnostic and therapeutic neuroendovascular procedures.

METHODS

Data were prospectively collected and retrospectively analyzed for consecutive patients undergoing diagnostic or therapeutic neuroendovascular procedures. Manual compression at the femoral access site was applied. The target for early ambulation was 2 hours after compression.

RESULTS

Three hundred forty-three patients were enrolled, of whom 295 were eligible for early ambulation. Diagnostic procedures totaled 214 (72.5%); therapeutic procedures, 81 (27.5%). Ambulation occurred at 2 hours for 82 patients who underwent a diagnostic and 11 patients who underwent a therapeutic procedure. Overall, 142 patients (66.4%) after a diagnostic and 21 patients (25.9%) after a therapeutic procedure ambulated within 3 hours; 94% of outpatients ambulated within 2 to 3 hours and were dismissed shortly thereafter. Delayed ambulation was related to nursing staff delays, recovery from general anesthesia, or patient preference. Fourteen patients (4.7%)—9 (4.2%) who had a diagnostic and 5 (6.2%) who had a therapeutic procedure—required delayed ambulation because of local oozing (8 patients), a hematoma of less than 5 cm (3 patients), a pseudoaneurysm (2 patients), or a large hematoma requiring surgical evacuation (1 patient).

CONCLUSION

Early ambulation is feasible and safe after diagnostic and therapeutic procedures and manual compression. A longer period of bed rest or the routine use of closure devices is often not required; thereby avoiding the costs associated with bed rest and the complications associated with closure devices.

Inter- and intraobserver agreement in CT characterization of nonaneurysmal perimesencephalic subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The perimesencephalic pattern of SAH as seen on unenhanced CT is associated with significantly better outcomes when compared to an aneurysmal pattern of SAH. The aim of this study was to determine the degree of inter- and intraoberver agreement for characterization of the NAPH as seen on unenhanced CT.

MATERIALS AND METHODS

We retrospectively reviewed the CT scans of 37 patients with spontaneous SAH, all of whom had undergone CT within 24 hours of onset of headache symptoms. All patients had undergone conventional cerebral angiography to confirm or exclude aneurysms or other vascular pathology. All 37 cases were angiographically confirmed nonaneurysmal SAHs. Four readers with neuroradiology subspecialty training independently evaluated CT images to characterize the hemorrhage pattern as compatible with the well-described NAPH. Each reader performed a second reading session blinded to the initial readings. The first and second sets of readings were performed approximately 4 months apart. Inter- and intraobserver agreement for characterization of the NAPH was determined by using the kappa statistic.

RESULTS

Of the 37 angiographically confirmed nonaneurysmal SAHs, there was unanimous agreement as to the hemorrhage pattern in 29 (78%) cases and disagreement in 8 (22%) cases. Overall, intraobserver agreement was good (kappa = 0.80). Interobserver agreement was also good (kappa = 0.79).

CONCLUSIONS

Overall, inter- and intraobserver agreement for the NAPH was good. There was, however, a level of disagreement among observers, thus suggesting that clinicians should be cautious when deciding whether to pursue follow-up imaging.

A prospective trial of 3T and 1.5T time-of-flight and contrast-enhanced MR angiography in the follow-up of coiled intracranial aneurysms

BACKGROUND AND PURPOSE

Endovascularly coiled intracranial aneurysms are increasingly being followed up with noninvasive MRA imaging to evaluate for aneurysm recurrences. It has not been well-established which MRA techniques are best for this application, however. Our aim was to prospectively compare 4 MRA techniques, TOF and CE-MRA at 1.5T and 3T, to a reference standard of DSA in the evaluation of previously endovascularly coiled intracranial aneurysms.

MATERIALS AND METHODS

Fifty-eight subjects with 63 previously coiled intracranial aneurysms underwent all 4 MRA techniques within 8 days of DSA. There were 2 outcome variables: coil occlusion class (class 1, complete; class 2, dog ear; class 3, residual neck; class 4, aneurysm filling) and change in degree of occlusion since the previous comparison. Sensitivity and specificity were computed for each MRA technique relative to the reference standard of DSA. Differences among the MRA techniques were evaluated in pair-wise fashion by using the McNemar test.

RESULTS

For the detection of any aneurysm remnant, the sensitivity was 85%-90% for all MRA techniques. Sensitivity dropped to 50%-67% when calculated for the detection of only the class 3 and 4 aneurysm remnants, because several class 3 and 4 remnants were misclassified as class 2 by MRA. CE-MRA at 1.5T and 3T misclassified fewer of the class 3 and 4 remnants than did TOF-MRA at 1.5T, as reflected by the significantly greater sensitivity for larger aneurysm remnants with CE-MRA relative to TOF-MRA at 1.5T (P = .0455 for both comparisons).

CONCLUSIONS

CE-MRA is more likely than TOF-MRA to classify larger aneurysm remnants appropriately. We recommend performing both CE-MRA and TOF-MRA in the follow-up of coiled intracranial aneurysms and at 3T if available.

Going viral: fusiform vertebrobasilar and internal carotid aneurysms with varicella angiitis and common variable immunodeficiency

Intracranial aneurysms in the pediatric population are relatively rare entities. Immunocompromised patients (often from HIV/AIDS or pharmacological immunosuppression) represent a significant fraction of children with cerebral aneurysms. One proposed mechanism of aneurysm formation in these patients is from direct infection of the affected arteries. In this study, the authors report on a case of a 14-year-old girl with common variable immunodeficiency with T-cell dysfunction and a CSF polymerase chain reaction test positive for varicella-zoster virus who underwent evaluation for carotid and basilar artery fusiform aneurysms.

Endovascular treatment of very small (3 mm or smaller) intracranial aneurysms: report of a consecutive series and a meta-analysis

BACKGROUND AND PURPOSE

We performed a meta-analysis of published studies on the endovascular treatment of very small intracranial aneurysms, including 71 patients treated at our institution.

METHODS

We conducted a computerized MEDLINE search of the literature for reports on the treatment of intracranial aneurysms with a maximum dimension of </=3 mm by using the search terms "small," "tiny," "intracranial aneurysm," "endovascular," and "coil." A total of 7 studies, including our institution's consecutive case series of 71 intracranial aneurysms, were included in this study. We extracted information regarding intraoperative complications, procedural mortality and morbidity, immediate- and long-term angiographic outcomes, and retreatment rate. The meta-analysis was performed with the statistical package Comprehensive Meta-Analysis.

RESULTS

Approximately 61% of the aneurysms in this meta-analysis presented as ruptured, whereas 39% of the aneurysms were unruptured. Procedural rupture rates for very small aneurysms was 8.3% (95% CI, 6.0% to 11.4%). The mortality rate due to procedural rupture was 2.4% (95% CI, 1.2% to 4.7%). The morbidity rate due to thromboembolic complications was 1.9% (95% CI, 0.9% to 3.9%). Subarachnoid hemorrhage within 1 month of treatment occurred in 1.6% (95% CI, 0.6% to 3.7%) of cases. There was no statistically significant difference between unruptured and ruptured aneurysms for any of these outcomes.

CONCLUSIONS

Our meta-analysis suggests that treatment of very small aneurysms is feasible and effective in >90% of treated aneurysms. However, the risk of periprocedural rupture is higher than that reported for larger aneurysms. Similarly, the combined rate of periprocedural mortality and morbidity is not negligible (7.3%) and should be considered when considering the best therapeutic option for these aneurysms.

Embolization of orbital varices with N-butyl cyanoacrylate as an aid in surgical excision: results of 4 cases with histopathologic examination

PURPOSE

To report the results of intervention with percutaneously injected n-butyl cyanoacrylate (NBCA) to embolize orbital varices followed by surgical resection.

DESIGN

Retrospective case series.

METHODS

Four patients with symptomatic orbital varices were treated with percutaneous injection of NBCA to embolize the varicosity before surgical resection. Intervention was indicated because of progressive orbital pain attributed to orbital varices. Three of the 4 described cases were associated with severe episodic proptosis. The vision was not affected by the orbital varix in any of the cases before intervention. Radiographic guidance was used during injection of the NBCA. Surgical resection was undertaken via orbitotomy immediately after embolization. The resected tissue was submitted for histopathologic evaluation.

RESULTS

Follow-up after surgery ranged from 7 to 19 months. All of the patients experienced relief of orbital pain. All patients noted transient binocular diplopia in extremes of gaze after the procedure, which resolved spontaneously. No patients had diplopia in primary gaze. No patient lost vision as a result of the procedure. There was no difficulty with procedure-related hemostasis in any of the cases.

CONCLUSIONS

Percutaneously injected NBCA seems to be useful and safe as an aid in visualization and hemorrhage prevention during surgical resection of symptomatic orbital varices.

Difficult aneurysms for endovascular treatment: overwide or undertall?

BACKGROUND AND PURPOSE

Aneurysm geometry has been shown to predict the need for adjunctive techniques in the endovascular treatment of intracranial aneurysms. We conducted a systematic retrospective study examining which thresholds of dome-to-neck ratio, maximum neck width, and aspect ratio of intracranial aneurysms best predict the need for adjunctive techniques in endovascular management.

MATERIALS AND METHODS

One hundred seventy-five consecutive patients who were selected for attempted embolization of 185 intracranial aneurysms were included in this study. Aneurysm dome-to-neck ratio (maximum dome width/maximum neck width), maximum neck width, and aspect ratio (dome height/maximum neck width) were measured on 2D digital subtraction angiography. Statistical analysis was conducted to determine which thresholds of dome-to-neck ratio, maximum neck width, and aspect ratio were most predictive of the need for adjunctive devices in endovascular management of these aneurysms.

RESULTS

We demonstrated that 75% of aneurysms with dome-to-neck ratios >1.6 (P < .0001), 75% of aneurysms with aspect ratios >1.6 (P < .0001), and 70% of aneurysms with neck diameters <4.0 mm (P < .0001) did not need adjunctive techniques in their management. Adjunctive techniques were essential to treatment of 80% of aneurysms with dome-to-neck ratios <1.2 (P = .02) and 89% of aneurysms with aspect ratios <1.2 (P < .0001). Multivariate logistic regression analysis demonstrated that aspect ratio was the best predictor of the need for an adjunctive device (P = .0004).

CONCLUSIONS

Aneurysms with aspect and dome-to-neck ratios >1.6 usually did not require adjunctive techniques. Aneurysms with aspect and dome-to-neck ratios <1.2 almost always required adjunctive techniques. In this single-center series, aspect ratio was the independent predictor of the need for adjunctive techniques in the endovascular management of intracranial aneurysms.