Effect of arachnoid plasty using fibrin glue membrane after clipping of ruptured aneurysm on the occurrence of complications and outcome in the elderly patients

Subdural Hygroma After Management of Ruptured Intracranial Aneurysms: Incidence, Associated Factors, Clinical Course, and Management Options

OBJECTIVE

To evaluate the incidence, associated factors, clinical course, and management options of subdural hygroma in patients treated for aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

From January 2013 until June 2022, 336 consecutive patients with aSAH underwent treatment in our center. No one patient was excluded from the study cohort. Computed tomography (CT) examinations were performed at admission, immediately after surgery and on the first postoperative day, and subsequently in case of any neurologic deterioration or, at least, once per week until discharge from the hospital. Thereafter, CT examinations were at the discretion of specialists in the rehabilitation facility, referring physicians, or neurosurgeons at the outpatient clinic.

RESULTS

The length of radiologic follow-up starting from CT at admission ranged from 1 to 3286 days (mean, 673 ± 895 days; median, 150 days). Subdural hygromas developed in 84 patients (25%). An average interval until this imaging finding from the initial CT examination was 25 ± 55 days (median, 8 days; range, 0-362 days). Evaluation in the multivariate model showed that patient age ≥72 years (P < 0.0001), cerebrospinal fluid (CSF) shunting (P < 0.0001), and microsurgical clipping of ruptured intracranial aneurysm (RIA; P < 0.0001) are independently associated with the development of subdural hygroma. In 54 of 84 cases (64%), subdural hygromas required observation only. Increase of the lesion size with (5 cases) or without (10 cases) appearance of midline shift was associated with patient age <72 years (P = 0.0398), decompressive craniotomy (P = 0.0192), and CSF shunting (P = 0.0009), whereas evaluation of these factors in the multivariate model confirmed independent association of only CSF shunting (P = 0.0003). Active management of subdural hygromas included adjustment of the shunt programmable valve opening pressure, cranioplasty, external subdural drainage, or their combination. Overall, during follow-up (mean, 531 ± 824 days; median, 119 days; range, 2-3285 days) after the start of observation or applied treatment, subdural hygromas showed either decrease (50 cases) or stabilization (34 cases) of their sizes, and no one lesion showed progression again.

CONCLUSIONS

The clinical course of subdural hygromas in patients treated for aSAH is generally favorable, but occasionally these lesions show progressive enlargement with or without the appearance of midline shift, which requires active management.

History and current progress of chronic subdural hematoma

Chronic subdural hematoma (CSDH) is characterized by an encapsulated collection of old blood. Although CSDH has become the most frequent pathologic entity in daily neurosurgical practice, there are some unresolved research questions. In particular, the causes and recurrent risk factors of CSDH remain as an object of debate. The split of the dural border layer forms a few tiers of dural border cells over the arachnoid layer. Tissue plasminogen activator plays an important role as a key factor of defective coagulation. Historically, CSDH has often been treated via burr hole craniostomy using a closed drainage system. Several different operative strategies and peri-operative strategies such as the addition of burr holes, addition of cavity irrigation, position of drain, or postural position, have been described previously. Although the direction of the drainage tube, residual air, low intensity of T1-weighted images on MRI, and niveau formation have been reported as risk factors for recurrence, antiplatelet or anticoagulant drug use has not yet been verified as a risk factor. Recently, pharmaceutical strategies, including atorvastatin, significantly improved the neurological function in CSDH patients. Many case series, without randomization, have been reported; and given its promising result, several randomized clinical trials using pharmaceutical as well as operative and perioperative strategies were initiated to obtain sufficient data. In contrast, relatively fewer basic studies have achieved clinical applications in CSDH, although it is one of the most common clinical entities. Further scientific basic research may be essential for achieving a novel treatment strategy for CSDH.

Effect of Surgical Arachnoid Plasty on Functional Outcome in Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

Various techniques have been performed to reduce subarachnoid clotting during aneurysmal neck clipping surgery. We considered that maintaining the physiologic cerebrospinal fluid circulation by performing arachnoid plasty after clipping during surgery would lead to the accelerated clearance of the subarachnoid clot.

METHODS

Patients in a prospectively maintained aneurysmal subarachnoid hemorrhage (aSAH) database at our institution and with aSAH that fulfilled the criteria were selected for this study. The incidence of delayed cerebral ischemia, angiographic vasospasm, 3-month functional outcome, and the amount of subarachnoid clot on computed tomography were compared between the 2 groups after matching.

RESULTS

From 2006 through 2016, 228 clipping cases met the inclusion criteria. Using propensity score matching, 89 cases of clipping without arachnoid plasty were matched to 89 cases of clipping with arachnoid plasty. Univariate analyses showed that arachnoid plasty significantly reduced the occurrence of hydrocephalus and incidence of poor outcome. Arachnoid plasty statistically significantly reduces the occurrence of hydrocephalus (odds ratio 0.267, 95% confidence interval 0.074-0.963, P < 0.05). Multivariate analysis also showed that arachnoid plasty was the factor reducing poor outcome at 3 months after aSAH (odds ratio 0.222, 95% confidence interval 0.075-0.661, P < 0.01).

CONCLUSIONS

The present study suggests that good hematoma clearance due to arachnoid formation reduced brain damage, cerebral vasospasm, and hydrocephalus, resulting in significantly fewer cases with poor functional prognosis. It therefore follows that procedures such as arachnoid plasty should be taken into consideration in order to improve outcome in surgical clipping.

Arachnoid Plasty to Prevent and Reduce Chronic Subdural Hematoma after Clipping Surgery for Unruptured Intracranial Aneurysm : A Meta-Analysis

Objective

Recent studies have reported that arachnoid plasty (ARP) using gelatin sponges with fibrin glue reduced the occurrence of chronic subdural hematoma (CSDH) following clipping surgery for unruptured intracranial aneurysm (UIA). This meta-analysis was conducted to collate further evidence for the efficacy of ARP in preventing postoperative CSDH.

Methods

Data of patients who underwent clipping surgery were extracted from PubMed, EMBASE, and Cochrane Central Register of Controlled Trials by two independent reviewers. A random effects model was used to investigate the efficacy of ARP by using odd ratios (ORs) and 95% confidence intervals (CIs). A meta-regression analysis for male sex was additionally preformed.

Results

Data from six studies with 1715 patients were consecutively included. Meta-analysis revealed that ARP was significantly associated with lower rates of CSDH development after surgical clipping for UIA (ARP group vs. control group : 3.2% vs. 7.2%; OR, 0.40; 95% CI, 0.18–0.93; I² =44.3%; p=0.110). Meta-regression analysis did not highlight any modifying effect of the male sex on postoperative CSDH development (p=0.951).

Conclusion

This meta-analysis indicated that ARP reduced the incidence rates of CSDH following clipping surgery for UIA. If feasible, ARP would be implemented as an additional surgical technique to prevent postoperative CSDH development during surgical clipping of UIA.

Study of Incidence and Factors: Risk and Preventive, of Chronic Subdural Hematoma/hygroma in Clipped Patients of Unruptured Intracranial Aneurysms - An Institutional Experience

Introduction

One of the underreported complications of clipping of unruptured aneurysm is chronic subdural hematoma/hygroma (CSDH). It can cause sudden deterioration and might need emergency evacuation. Recently, very few papers have studied its incidence and predisposing factors. We are reporting our institutional experience of it along with the study of its risk factors and possible pathogenesis.

Methodology

Totally 91 postoperative patients of unruptured aneurysms were retrospectively analyzed. Totally 21 patients had CSDH who were operated. In rest seventy patients, there was no CSDH.

Results

Male sex, old age, anticoagulant use, presence of pneumocephalus and dead space were significantly associated with occurrence of CSDH, whereas arachnoidoplasty significantly protected against it. There was no significant relation of CSDH with Gorei-san use.

Conclusions

We recommend arachnoidoplasty should be carried out in all patients of clipping of unruptured aneurysm. Male patients or/and patients with dead space with pneumocephalus must be given extra attention like avoiding any dead space in postoperative period, doing arachnoidoplasty and regular follow up till 1^st year.

Modified Arachnoid Plasty Reduces Chronic Subdural Hematoma after Unruptured Aneurysm Clipping : Technical Note

Objective

Chronic subdural hematoma (CSDH) is a rare complication of unruptured intracranial aneurysm (UIA) clipping surgery. To prevent postoperative CSDH by reducing subdural fluid collection, we applied the modified arachnoid plasty (MAP) during the UIA clipping surgery to seal the dissected arachnoid plane.

Methods

This retrospective study included 286 patients enrolled from July 2012 to May 2015. We performed arachnoid plasty in all patients, with MAP used after June 17, 2014. Patients were divided into two groups (non-MAP vs. MAP), and by using uni- and multivariate analyses, baseline characteristics, and relationships with postoperative CSDH between the two groups were analyzed. The degree of preoperative brain atrophy was estimated using the bicaudate ratio (BCR) index.

Results

Ten patients (3.5%) among 286 patients had postoperative CSDH after clipping. Nine (3.1%) were in the non-MAP group, and one (0.9%) was in the MAP group. The higher BCR index showed statistical significance with occurrence of postoperative CSDH in both uni- (p=0.018) and multivariate (p=0.012; odds ratio [OR], 8.547; 95% confidence interval [CI], 1.616–45.455) analyses. MAP was associated with a lower risk of postoperative CSDH (p=0.022; OR, 0.068; 95% CI, 0.007–0.683).

Conclusion

This study shows that the degree of preoperative brain atrophy is associated with an increased occurrence of CSDH after clipping and that MAP could help reduce the risk of postoperative CSDH after unruptured aneurysm clipping via a lateral supraorbital approach.

Postoperative Subdural Air Collection Is a Risk Factor for Chronic Subdural Hematoma after Surgical Clipping of Cerebral Aneurysms

The precise mechanism of the development of chronic subdural hematoma (CSDH) as a postoperative complication after aneurysmal clipping remains unclear. The purpose of this study was to identify the independent risk factors for CSDH after craniotomy for aneurysmal clipping and to elucidate the relationship between CSDH and subdural air (SDA) collection immediately after surgery. The medical records and radiologic data of 344 patients who underwent surgical clipping of unruptured aneurysms from July 2010 to July 2016 were retrospectively evaluated. Patient characteristics, aneurysm characteristics, and operation data were statistically analyzed to reveal their relationships with CSDH development. Among the 344 patients, 46 (13.4%) developed CSDH and 13 (3.8%) required subsequent burr-hole surgery for evacuation and irrigation. Multivariate analyses showed that advanced age (P < 0.0001), male sex (P = 0.035), and surgical clipping of multiple aneurysms (P = 0.037) were independent preoperative predictors of CSDH development. Advanced age (P = 0.0005) and postoperative SDA after clipping surgery (P < 0.0001) were independent postoperative predictors of CSDH development. Postoperative SDA and CSDH were not associated with the individual surgeon or operation time. Postoperative severe SDA was significantly associated with the ipsilateral development of CSDH, irrespective of the side of craniotomy. Postoperative SDA is an independent risk factor for CSDH after surgical clipping of unruptured aneurysms and is as important as advanced age, male sex, and surgical clipping of multiple aneurysms in predicting CSDH.

Validation of effectiveness of keyhole clipping in nonfrail elderly patients with unruptured intracranial aneurysms

OBJECTIVE

Advanced age is known to be associated with a poor prognosis after surgical clipping of unruptured intracranial aneurysms (UIAs). Keyhole clipping techniques have been introduced for less invasive treatment of UIAs. In this study, the authors compared the complications and clinical and radiological outcomes after keyhole clipping between nonfrail elderly patients (≥ 70 years) and nonelderly patients.

METHODS

Keyhole clipping (either supraorbital or pterional) was performed to treat 260 cases of relatively small (≤ 10 mm) anterior circulation UIAs. There were 62 cases in the nonfrail elderly group (mean age 72.9 ± 2.6 years [± SD]) and 198 cases in the nonelderly group (mean age 59.5 ± 7.6 years). The authors evaluated mortality and morbidity (modified Rankin Scale score > 2 or Mini–Mental State Examination [MMSE] score < 24) at 3 months and 1 year after the operation, the general cognitive function by MMSE at 3 months and 1 year, anxiety and depression by the Beck Depression Inventory (BDI) and Hamilton Rating Scale for Depression (HAM-D) at 3 months, and radiological abnormalities and recurrence at 1 year.

RESULTS

Basic characteristics including comorbidities, frailty, and BDI and HAM-D scores were not significantly different between the 2 groups, whereas the MMSE score was slightly but significantly lower in the elderly group. Aneurysm location, largest diameter, type of keyhole surgery, neck clipping rate, and hospitalization period were not significantly different between the 2 groups. The incidence of chronic subdural hematoma was not significantly higher in the elderly group than in the nonelderly group (8.1% vs 4.5%, p = 0.332); rates of other complications including stroke and epilepsy were not significantly different. Lacunar infarction occurred in 3.2% of the elderly group and 3.0% of the nonelderly group. No patient in the elderly group required re-treatment or demonstrated recurrence of clipped aneurysms. The MMSE score at 3 months significantly improved in the nonelderly group but did not change in the elderly group. The BDI and HAM-D scores at 3 months were significantly improved in both groups. No patient died in either group. The morbidity at 3 months and 1 year in the elderly group (1.6% and 4.8%, respectively) was not significantly different from that in the nonelderly group (2.0% and 1.5%, respectively).

CONCLUSIONS

Keyhole clipping for nonfrail elderly patients with relatively small anterior circulation UIAs did not significantly increase the complication, mortality, or morbidity rate; hospitalization period; or aneurysm recurrence compared with nonelderly patients, and it was associated with improvement in anxiety and depression. Keyhole clipping to treat UIAs in the nonfrail elderly is an effective and long-lasting treatment.

Efficacy of Arachnoid-Plasty on Chronic Subdural Hematoma Following Surgical Clipping of Unruptured Intracranial Aneurysms

BACKGROUND

We aimed to elucidate the effects of arachnoid plasty (ARP) on chronic subdural hematoma (CSDH) occurrence following clipping surgery.

METHODS

In total 217 patients (ARP, n = 97; non-ARP, n = 120) who had undergone unruptured intracranial aneurysm (UIA) surgical clipping via the pterional approach were retrospectively assessed. Predisposing factors for CSDH development following the surgery were investigated. Thickness and volume of the subdural fluid collection (SDFC) were measured to determine whether ARP affects postoperative SDFC.

RESULTS

The occurrence of postoperative CSDH was higher in patients without ARP compared to those with ARP (12.5 vs. 3.1%; P = 0.01). In multivariate analyses, having an SDFC volume ≥15 mL on postoperative day (POD) 8, (odds ratio [OR] = 15.113; range = 3.159-72.290), and male sex (OR = 4.274; range = 1.291-14.148) were identified as independent predictive factors. Having had ARP (OR = 0.228; range = 0.056-0.927) was, as an independent variable, negatively correlated with the occurrence of CSDH (P < 0.05). Moreover, SDFC volume ≥15 ml on POD 8 was significantly less common in the ARP group compared with the non-ARP group (P = 0.03).

CONCLUSION

Patients who underwent ARPs developed fewer CSDHs following UIA clipping surgery. The factors that predicted the development of CSDH included male sex, SDFC volume on POD 8, and ARP. In addition, the ARP patients had lower SDFC volumes (<15 mL). These findings suggested that ARP reduced the incidence of CSDHs after surgical clippings in patients with unruptured aneurysms.

Predicting Factors of Chronic Subdural Hematoma Following Surgical Clipping in Unruptured and Ruptured Intracranial Aneurysm

Objective

The aim of this study is to analyze the differences in the incidence, predicting factors, and clinical course of chronic subdural hematoma (CSDH) following surgical clipping between unruptured (UIA) and ruptured intracranial aneurysm (RIA).

Methods

We conducted a retrospective analysis of 752 patients (UIA : 368 and RIA : 384) who underwent surgical clipping during 8 years. The incidence and predicting factors of CSDH development in the UIA and RIA were compared according to medical records and radiological data.

Results

The incidence of postoperative CSDH was higher in the UIA (10.9%) than in the RIA (3.1%) (p=0.000). In multivariate analysis, a high Hounsfield (HF) unit (blood clots) for subdural fluid collection (SFC), persistence of SFC ≥5 mm and male sex in the UIA and A high HF unit for SFC and SFC ≥5 mm without progression to hydrocephalus in the RIA were identified as the independent predicting factors for CSDH development (p<0.05).

Conclusion

There were differences in the incidence and predicting factors for CSDH following surgical clipping between UIA and RIA. Blood clots in the subdural space and persistence of SFC ≥5 mm were predicting factors in both UIA and RIA. However, progression to hydrocephalus may have in part contributed to low CSDH development in the RIA. We suggest that cleaning of blood clots in the subdural space and efforts to minimize SFC ≥5 mm at the end of surgery is helpful to prevent CSDH following aneurysmal clipping.

Postoperative subdural hygroma and chronic subdural hematoma after unruptured aneurysm surgery: age, sex, and aneurysm location as independent risk factors

OBJECTIVE

This study investigated the incidence and risk factors for the postoperative occurrence of subdural complications, such as a subdural hygroma and resultant chronic subdural hematoma (CSDH), following surgical clipping of an unruptured aneurysm. The critical age affecting such occurrences and follow-up results were also examined.

METHODS

The case series included 364 consecutive patients who underwent aneurysm clipping via a pterional or superciliary keyhole approach for an unruptured saccular aneurysm in the anterior cerebral circulation between 2007 and 2013. The subdural hygromas were identified based on CT scans 6-9 weeks after surgery, and the volumes were measured using volumetry studies. Until their complete resolution, all the subdural hygromas were followed using CT scans every 1-2 months. Meanwhile, the CSDHs were classified as nonoperative or operative lesions that were treated by bur-hole drainage. The age and sex of the patients, aneurysm location, history of a subarachnoid hemorrhage (SAH), and surgical approach (pterional vs superciliary) were all analyzed regarding the postoperative occurrence of a subdural hygroma or CSDH. The follow-up results of the subdural complications were also investigated.

RESULTS

Seventy patients (19.2%) developed a subdural hygroma or CSDH. The results of a multivariate analysis showed that advanced age (p = 0.003), male sex (p < 0.001), middle cerebral artery (MCA) aneurysm (p = 0.045), and multiple concomitant aneurysms at the MCA and anterior communicating artery (ACoA) (p < 0.001) were all significant risk factors of a subdural hygroma and CSDH. In addition, a receiver operating characteristic (ROC) curve analysis revealed a cut-off age of > 60 years, which achieved a 70% sensitivity and 69% specificity with regard to predicting such subdural complications. The female patients ≤ 60 years of age showed a negligible incidence of subdural complications for all aneurysm groups, whereas the male patients > 60 years of age showed the highest incidence of subdural complications at 50%-100%, according to the aneurysm location. The subdural hygromas detected 6-9 weeks postoperatively showed different follow-up results, according to the severity. The subdural hygromas that converted to a CSDH were larger in volume than the subdural hygromas that resolved spontaneously (28.4 ± 16.8 ml vs 59.6 ± 38.4 ml, p = 0.003). Conversion to a CSDH was observed in 31.3% (5 of 16), 64.3% (9 of 14), and 83.3% (5 of 6) of the patients with mild, moderate, and severe subdural hygromas, respectively.

CONCLUSIONS

Advanced age, male sex, and an aneurysm location requiring extensive arachnoid dissection (MCA aneurysms and multiple concomitant aneurysms at the MCA and ACoA) are all correlated with the occurrence of a subdural hygroma and CSDH after unruptured aneurysm surgery. The critical age affecting such an occurrence is 60 years.

Minimizing Collateral Brain Injury Using a Protective Layer of Fibrin Glue: Technical Note

BACKGROUND

Neurosurgical procedures expose the brain surface to a constant risk of collateral injury. We describe a technique where the brain surface is covered with a protective layer of fibrin glue and discuss its advantages.

METHODS

A thin layer of fibrin glue was applied on the brain surface after its exposure in 34 patients who underwent different craniotomies for tumoral and vascular lesions. Data of 35 more patients who underwent standard microsurgical technique were collected as a control group. Cortical and pial injuries were evaluated using an intraoperative visual scale. Eventual abnormal signals at the early postoperative T2-weighted fluid-attenuated inversion recovery (T2FLAIR) magnetic resonance imaging (MRI) sequences were evaluated in oncological patients.

RESULTS

Total pial injury was noted in 63% of cases where fibrin glue was not used. In cases where fibrin glue was applied, a significantly lower percentage of 26% (P < 0.01) had pial injuries. Only 9% had injuries in areas covered with fibrin glue (P < 0.0001). Early postoperative T2FLAIR MRI confirmed the differences of altered signal around the surgical field in the two populations.

CONCLUSION

We propose beside an appropriate and careful microsurgical technique the possible use of fibrin glue as alternative, safe, and helpful protection during complex microsurgical dissections. Its intrinsic features allow the neurosurgeon to minimize the cortical manipulation preventing minor collateral brain injury.

Intraoperative Arachnoid Plasty Has Possibility to Prevent Chronic Subdural Hematoma after Surgery for Unruptured Cerebral Aneurysms

Some patients develop chronic subdural hematomas (CSDHs) after the clipping/coating of unruptured aneurysms. The risk factors are not well understood and while no preventive methods are currently available, arachnoid plasty (ARP) may intercept the development of postoperative CSDH. We investigated the risk factors for CSDH and the usefulness of ARP to prevent postoperative CSDH. Between January 2009 and June 2013, 393 patients underwent 416 aneurysm surgeries via the pterional approach at Kushiro Kojinkai Memorial Hospital. Of these, 394 aneurysms (371 patients) were included in this study. Using multivariate analysis we evaluated the relationship between the patient demographics and clinical characteristics, and the development of postoperative symptomatic CSDH. We also studied the effect of ARP performed during aneurysm surgery. We found that symptomatic CSDH developed after 20 (5.1%) of the 394 operations; it was addressed by burr hole surgery and evacuation/irrigation. Male gender, advanced age, and oral anticoagulant therapy were significant risk factors for CSDH. Additive ARP, performed in the course of 132 surgeries (33.5%) was found to be a significant negative risk factor. The incidence of CSDH was significantly lower in patients who had undergone ARP than in patients who had not undergone it (0.8% vs. 7.3%, p < 0.01). We first report that ARP is useful for the prevention of CSDH in patients treated by aneurysm surgery.

Efficacy of arachnoid plasty with collagen sheets and fibrin glue: An in vitro experiment and a case review

Background:

Postoperative subdural fluid collection sometimes occurs after clipping of cerebral aneurysms. Arachnoid plasty is used to prevent such postoperative complications; however, the optimal materials for arachnoid plasty remain unclear. In this study, we aimed to clarify the optimal materials for arachnoid plasty and report our experience of arachnoid plasty after clipping of unruptured aneurysms.

Methods:

In an in vitro experiment, adhesive strengths of three materials permitted for use in the intradural space, such as collagen sheets, gelatin sponge, and oxidized cellulose sheets, were measured by assessing their water pressure resistance. Then, 80 consecutive cases surgically treated unruptured cerebral aneurysms were retrospectively reviewed to examine the occurrence rate of postoperative subdural fluid collection.

Results:

The collagen sheet exhibited the greatest adhesive strength, so we used collagen sheets for the arachnoid plasty procedures. In all of these cases, arachnoid plasty was performed with fibrin glue-soaked collagen sheets. No postoperative subdural fluid collection, inflammation, or allergic reactions occurred in any case.

Conclusions:

The present study suggests that collagen sheet might be one of the optimal materials for arachnoid plasty. This technique is simple and may be effective to prevent subdural fluid collection after clipping.

Incidence and risk factors of chronic subdural hematoma after surgical clipping for unruptured anterior circulation aneurysms

OBJECTIVE

Chronic subdural hematoma (CSDH) is a rare complication of unruptured aneurysm clipping surgery. The purpose of this study was to identify the incidence and risk factors of postoperative CSDH after surgical clipping for unruptured anterior circulation aneurysms.

METHODS

This retrospective study included 518 patients from a single tertiary institute from January 2008 to December 2013. CSDH was defined as subdural hemorrhage which needed surgical treatment. The degree of brain atrophy was estimated using the bicaudate ratio (BCR) index. We used uni- and multivariate analyses to identify risk factors correlated with CSDH.

RESULTS

Sixteen (3.1%) patients experienced postoperative CSDH that required burr hole drainage surgery. In univariate analyses, male gender (p<0.001), size of aneurysm (p=0.030), higher BCR index (p=0.004), and the use of antithrombotic medication (p=0.006) were associated with postoperative CSDH. In multivariate analyses using logistic regression test, male gender [odds ratio (OR) 4.037, range 1.287-12.688], high BCR index (OR 5.376, range 1.170-25.000), and the use of antithrombotic medication (OR 4.854, range 1.658-14.085) were associated with postoperative CSDH (p<0.05). Postoperative subdural fluid collection and arachnoid plasty were not showed statistically significant difference in this study.

CONCLUSION

The incidence of CSDH was 3.1% in unruptured anterior circulation aneurysm surgery. This study shows that male gender, degree of brain atrophy, and the use of antithrombotic medication were associated with postoperative CSDH.

Clinical characteristics and risk factors of chronic subdural haematoma associated with clipping of unruptured cerebral aneurysms

Chronic subdural haematoma (CSDH) is an uncommon but potentially serious complication of clipping unruptured cerebral aneurysms. We conducted a study to identify the patients who are at risk of developing postoperative CSDH. The data from 713 consecutive patients who underwent clipping of unruptured anterior circulation aneurysms were reviewed, and risk factors correlated with CSDH were identified by multivariate regression analysis of demographic variables. Fifteen patients (2.1%) developed CSDH after the surgery. Advanced age (odds ratio [OR] 1.151, 95% confidence interval [CI] 1.051-1.261) and male gender (OR 3.167, 95% CI 1.028-9.751) were correlated with CSDH. Subsequently, all 713 patients were quadrichotomized on the basis of gender and age, with 70 years as the cut-off value for age. The frequency of CSDH in men <70 years of age was 1.3% and that in men ≥70 years of age was 15.1%, with risk of CSDH was significantly higher in the older men (OR 13.39; 95% CI: 3.42-52.44). The frequency of CSDH in women <70 years of age was 0.6% and that in women ≥70 years of age was 3.7%. As in men, the risk of CSDH was significantly higher in the older women (OR 6.69, 95% CI 1.10-40.73). The interval between the aneurysm clipping and CSDH development was 0.5-6 months, suggesting that clinical observation should be continued up to 6 months after surgery. Although prognosis for patients with a postoperative CSDH complication is generally favourable, the risk of CSDH should be taken into account when considering elective clipping of unruptured aneurysms in patients ≥70 years of age.

Incidence and risk factors of chronic subdural hematoma after aneurysmal clipping

OBJECTIVE

Chronic subdural hematoma (CSDH) after aneurysmal clipping is a rare complication, but its incidence and risk factors are not known in detail. We retrospectively reviewed our cases requiring surgery for CSDH after clipping.

METHODS

In our hospital, between January 2000 and December 2006, 794 patients (unruptured, 58.0%) underwent clipping surgery for aneurysm of the anterior circulation. We reviewed incidence and risk factors of CSDH after clipping. For the past 2 years, we reviewed all computed tomography scans for 163 unruptured aneurysms, and examined the relationship between an increase of subdural fluid collection (SFC) and development of CSDH.

RESULTS

Fifteen patients (1.9%) developed CSDH after clipping, which required evacuation. Among those, 13 had unruptured aneurysms (2.8%), a much higher percentage than for ruptured aneurysms (0.9%). On univariate statistical analysis, risk factors of CSDH were associated with advanced age (P = 0.0005), male gender (P = 0.04), and unruptured aneurysms (P = 0.02). Aneurysmal location was not related to the development of postoperative CSDH. Contralateral CSDH occurred in 3 patients, but no middle cerebral artery aneurysm developed contralateral CSDH. An increase in postoperative SFC during 1 week was a significant risk factor for CSDH (P = 0.001).

CONCLUSIONS

In addition to the classic risk factors, this study showed that clipping for unruptured aneurysms carries a higher risk for CSDH compared to ruptured aneurysms. We suggest that an increase of SFC during 1 week postoperatively can be a factor in predicting CSDH after clipping.

Allergic reaction following arachnoid plasty with a fibrin sealant

A 65-year-old woman underwent surgical treatment of an unruptured aneurysm in the left middle cerebral artery. Surgical craniotomy using arachnoid plasty with a fibrin sealant was completed without incident, but abrupt neurological deterioration occurred on the 9th postoperative day. Antibiotic treatment was given, but the symptoms did not resolve. Neuroimaging and physical findings indicated allergic reaction rather than infectious process. Therefore, systemic steroids were administered that resulted in dramatic resolution of symptoms. Nine months later, lymphocyte stimulation test of materials used in arachnoid plasty revealed positive response to a component of the combination pair in fibrin glue. The fibrin sealant placement method is a widely accepted and familiar technique, but surgeons should anticipate possible allergic reactions such as those observed in the present case.