Matthew F. Lawson

Length of Stay and Total Hospital Charges of Clipping Versus Coiling for Ruptured and Unruptured Adult Cerebral Aneurysms in the Nationwide Inpatient Sample Database 2002 to 2006

Background and Purpose— We have previously reported the difference in length of stay and hospital charges for patients with cerebral aneurysms treated with either clipping or coiling at our institution. We now report an analysis of the same comparison at a national level conducted using the Nationwide Inpatient Sample database. Methods— We obtained the Nationwide Inpatient Sample from the Healthcare Cost and Utilization Project, Agency for Healthcare Quality and Research. The Nationwide Inpatient Sample is the largest all-payer inpatient care database in the US and represents ≈20% of all inpatient admissions to US nonfederal hospitals. Hospitalizations for clipping or coiling of ruptured and unruptured cerebral aneurysms from 2002 to 2006 were identified by cross-matching International Classification of Diseases-9 codes for diagnoses of subarachnoid hemorrhage (430) or unruptured cerebral aneurysm (437.3) with procedure codes for clipping (39.51) or coiling (39.79, 39.72, or 39.52) of cerebral aneurysms. Length of hospital stay and total hospital charges for clipping and coiling were compared using linear mixed models adjusted for the following patient and hospital-specific factors: gender, age, race/ethnicity, admission source and type, median income level in patients postal code of residence, payer for care, comorbidities, and hospital cerebral aneurysm case volume, bed size, teaching status, rural/urban location, and geographic region. Results— There were 9635 hospitalizations for ruptured aneurysm treatments (6019 clipping, 3616 coiling) and 9399 hospitalizations for unruptured aneurysm treatments (4700 clipping, 4699 coiling). For ruptured aneurysm patients, after adjusting for the effects of patient-specific and hospital-specific factors, clipping compared to coiling was associated with significantly longer length of stay (P<0.0001) and significantly higher total hospital charges (P<0.0001). For unruptured aneurysm patients, clipping compared to coiling was associated with significantly longer length of stay (P<0.0001) and significantly higher total hospital charges (P<0.0001). After adjusting for the effects of hospital-level and patient-level characteristics, clipping as compared to coiling was associated with an average of 1.2-times more days in hospitalization for ruptured patients and was associated with an average of 1.8-times more days in hospitalization for unruptured patients. On average, clipping resulted in

Stent-associated flow remodeling causes further occlusion of incompletely coiled aneurysms.

15 325 more in total charge for ruptured patients and resulted in

Delayed intraparenchymal hemorrhage following pipeline embolization device treatment for a giant recanalized ophthalmic aneurysm

11 263 more in total charge for unruptured patients after considering all relevant hospital and patient characteristics. Conclusions— The results of this nationwide analysis differed from the findings of our single institution study. Clipping compared to coiling was associated with significantly longer lengths of stay and significantly higher total hospital charges for both ruptured and unruptured aneurysm patients.

Rationale for Treating Unruptured Intracranial Aneurysms: Actuarial Analysis of Natural History Risk versus Treatment Risk for Coiling or Clipping Based on 14,050 Patients in the Nationwide Inpatient Sample Database

BACKGROUND:Incomplete coil occlusion is associated with increased risk of aneurysm recurrence. We hypothesize that intracranial stents can cause flow remodeling, which promotes further occlusion of an incompletely coiled aneurysm. OBJECTIVE:To study our hypothesis by comparing the follow-up angiographic outcomes of stented and nonstented incompletely coiled aneurysms. METHODS:From January 2006 through December 2009, the senior author performed 324 initial coilings of previously untreated aneurysms, 145 of which were Raymond classification 2 and 3. Follow-up angiographic studies were available for 109 of these aneurysms (75%). Angiographic outcomes for stented vs nonstented incompletely coiled aneurysms were compared. A multivariate analysis was performed to identify factors related to the progression of occlusion at follow-up, with adjustment for aneurysm location, size, neck size, Hunt-Hess grade, stent use, initial Raymond score, packing density, age, sex, and medical comorbidities. RESULTS:Of the 109 aneurysms, 37 were stented and 72 were not stented. With a median follow-up time of 15.4 months, 33 stented aneurysms (89%) progressed to complete occlusion compared with 29 nonstented aneurysms (40%). Recanalization rates were lower in the stented group (8.1%) compared with the nonstented group (37.5%; P < .001). On multivariate analysis, stent use (odds ratio, 18.5; 95% confidence interval, 4.3-76.9) and packing density (odds ratio, 1.093; 95% confidence interval, 1.021-1.170) were significant predictors of the progression of occlusion. Aneurysm size was negatively correlated with the progression of occlusion (odds ratio, 0.844; 95% confidence interval, 0.724-0.983). CONCLUSION:Stent-assisted coiling causes progression of occlusion, possibly by a flow remodeling effect. The odds of progression of occlusion of stent-coiled aneurysms were 18.5 times that of nonstented aneurysms.

Enhanced staff communication and reduced near-miss errors with a neurointerventional procedural checklist

The pipeline embolization device has demonstrated clinical success in the management of complex intracranial aneurysms arising along the anterior intracranial circulation with a relatively low complication profile. A case report is presented which describes a novel complication of delayed intraparenchymal hemorrhage following deployment of a pipeline embolization device for the treatment of a previously ruptured partially thrombosed ophthalmic segment aneurysm.

The stent anchor technique for distal access through a large or giant aneurysm

OBJECTIVE The treatment of small unruptured intracranial aneurysms has been questioned based on the results of the International Study of Unruptured Intracranial Aneurysms. Our objective was to compare natural history rupture risk versus treatment risk for coiling and clipping small unruptured aneurysms using data in the Nationwide Inpatient Sample database. METHODS Data for clipping and coiling of unruptured aneurysms was collected from the Nationwide Inpatient Sample from 2002-2008. Treatment risks were adjusted for age, gender, and medical comorbidities. Logistic regression models were used to create curves depicting the estimated probability of poor outcome as a function of patient age for clipping and coiling. These treatment risk curves were compared against natural history actuarial risk curves calculated from four prominent studies. RESULTS There were 14,050 hospitalizations: 7439(53%) coiling; 6611(47%) clipping. For patients who underwent coiling or clipping, the mortality rate was 2.17% and 2.66%, and the morbidity rate was 2.16% and 4.75%, respectively. The adjusted risk of poor outcome from clipping and coiling, when modeled against most natural history studies, demonstrates a treatment benefit for clipping for patients <70 years and for coiling patients <81 years. Models using the International Study of Unruptured Intracranial Aneurysms data demonstrate a treatment benefit for clipping for patients <61 years and for coiling for patients <70 years. CONCLUSIONS Both clipping and coiling of unruptured intracranial aneurysms are safe. This analysis demonstrates rationale for clipping small unruptured aneurysms in patients <61-70 years and coiling small unruptured aneurysms in patients <70-80 years. Treatment beyond these age ranges is associated with increased risk of poor outcome.

Occurrence of angiographic femoral artery complications after vascular closure with Mynx and AngioSeal

Introduction Over the past several decades, checklists have emerged in a variety of different patient care settings to help reduce medical errors and ensure patient safety. To date, there have been no published accounts demonstrating the effectiveness of checklists designed specifically for the unique demands of neurointerventional procedures. Methods A three-part, 20-item checklist was developed specific to neurointerventional procedures using the WHO surgical checklist as a template. Staff members (nurses, radiation technologists and physicians) were surveyed regarding near-miss adverse events and the quality of communication immediately following each neurointerventional procedure for 4 weeks prior to implementation of the checklist and again for 4 weeks after using the checklist. Staff members were asked to complete final surveys at the end of the study period. Results 71 procedures were performed during the 4 weeks prior to checklist implementation and 60 procedures were performed during the 4 weeks after institution of the checklist. Post-checklist surveys indicated significantly improved communication compared with pre-checklist surveys (χ2 29.4, p<0.001). The number of adverse events was lower after checklist implementation for eight of the nine adverse event types (not individually significant), but the total number of adverse events was significantly lower after checklist implementation (χ2 11.4, p=0.001). Final staff surveys were uniformly positive with 95% of individuals indicating that the checklist should be continued in the department. Conclusions Use of a neurointerventional procedural checklist resulted in statistically significant improvements in team communication and a significant reduction in total adverse events, with uniformly positive staff feedback.

Concomitant intracranial pressure monitoring during venous sinus stenting for intracranial hypertension secondary to venous sinus stenosis.

Large and giant aneurysms pose significant challenges to the endovascular techniques of coil embolization or parent vessel reconstruction. Many large aneurysms are wide-necked with bulbous domes and frequently require stent-assisted coiling or flow diversion to reconstruct and preserve flow through the parent artery. Often the wire must be looped in the dome before catheterization of the exiting portion of the parent vessel is possible. In addition, it can be challenging to obtain stable distal purchase of the microcatheter that will allow the loop to be withdrawn from the aneurysm without the entire microcatheter unwinding, resulting in herniation into the aneurysm or proximal vessels. The stent anchor technique, a novel method of obtaining distal purchase that allows straightening of the catheter loop within a large aneurysm for the purposes of stenting for vessel reconstruction across large or giant aneurysms, is presented. This technique may facilitate the use of new stent technologies in the treatment of large aneurysms that have traditionally been exceedingly difficult to treat via an endovascular approach.

Timing of aneurysm surgery: the International Cooperative Study revisited in the era of endovascular coiling

Introduction There have been recent reports of high vascular complication rates after the use of the Mynx vascular closure device (VCD). At our institution, vascular complications due to these devices have rarely been encountered. A study was undertaken to retrospectively compare angiographic abnormalities seen after femoral artery closure by both the Mynx and AngioSeal VCDs to provide further insight into the risks associated with VCDs. Methods All adult patients who underwent deployment of either a Mynx or AngioSeal VCD and subsequently underwent repeat angiography within the next 30 days between 1 July 2010 and 1 April 2011 were reviewed. Two independent blinded radiologists compared blinded pre-procedure and follow-up femoral angiograms for the presence of pseudoaneurysm or other vascular abnormality. Hospital records were reviewed for major or minor complications of the groin site or femoral artery. Results Thirty patients (31 angiograms) underwent vascular closure with a Mynx and 57 patients (69 angiograms) received an AngioSeal. The average time elapse until repeat femoral angiography was 6.2 days (range 1–21, median 5.5 days) in the Mynx group and 6.3 days (range 0–30, median 5 days) in the AngioSeal group. Two pseudoaneurysms and one minor stenosis were identified in the AngioSeal group. No angiographic abnormalities were seen in the Mynx group. No intraluminal filling defects were demonstrated on any of the follow-up femoral angiograms. One patient who received an AngioSeal developed a delayed minor groin site hematoma that did not require surgical intervention. Conclusions Angiographic complications were seen in only 3% of patients after closure with Mynx or AngioSeal VCDs. There were no clinically significant groin site or vascular complications. These data suggest that both VCDs are safe for use after angiography with a low rate of femoral artery complications.

Nonaneurysmal Subarachnoid Hemorrhage: An Update

Background There is a growing body of literature supporting venous sinus stenosis as a causative etiology for many patients diagnosed with idiopathic intracranial hypertension. Recent series have documented improvement in the pre- and post-stenosis venous pressure gradient as well as clinical symptoms after stenting. Concomitant real time intracranial pressure (ICP) monitoring has not been previously described during venous sinus stenting. Case report A woman in her twenties presented with rapidly progressive visual loss and cranial neuropathies with an MRI revealing high grade right transverse sinus stenosis. Lumbar puncture demonstrated an opening pressure >55 cm H2O. Her vision and cranial neuropathies continued to worsen despite ventriculoperitoneal shunting. A parenchymal ICP monitoring wire was placed, revealing ICP persistently >70 cm H2O. She underwent venography and a pre- to post-stenosis pressure gradient of 55 mm Hg was measured. The patient underwent sinus stenting resulting in a near immediate reduction in her ICP from 70 to 20 cm H2O within 30 s after deployment. Her ICP completely normalized within 24 h of stenting. Conclusions A case is presented of severe intracranial hypertension with rapidly progressive neurologic decline despite CSF diversion secondary to venous sinus stenosis that resolved following venous sinus stenting. This is the first report of real time ICP monitoring during venous sinus stenting.