Anterior Choroidal Artery Aneurysm Surgery: Ischemic Complications and Clinical Outcomes Revisited

Objective

Surgical results for anterior choroidal artery (AChA) aneurysms have previously been reported as unsatisfactory due to inadvertent occlusion of the AChA, while the low incidence of AChA aneurysms hampers the accumulation of surgical experience. The authors reviewed their related surgical experience to document the ischemic complications and surgical outcomes.

Methods

Identification of the AChA at its origin by rigorous visual scrutiny, careful microdissection, and meticulous clip placement to avoid the AChA origin are all crucial surgical maneuvers. A retrospective review of a surgical series of 62 consecutive cases of an AChA aneurysm between 2004 and 2012 was performed.

Results

All patients, except for five (8.1%) with a small residual neck, showed complete aneurysm obliteration in postoperative angiographic evaluations. There was no incidence of procedure-related permanent AChA syndrome or oculomotor nerve palsy, while three (4.8%) patients suffered from transient AChA syndrome. The clinical outcomes [the 3-month modified Rankin Scale (mRS)] of the patients were related to their preoperative World Federation of Neurologic Surgeons (WFNS) grade. As regards the 3-month mRS, significant differences were found between patients with an unruptured aneurysm (WFNS grade 0; n=20), good-grade subarachnoid hemorrhage (WFNS grade 1-3; n=30), and poor-grade subarachnoid hemorrhage (WFNS grade 4-5; n=4).

Conclusion

In surgical treatment of AChA aneurysms, a risk of AChA insufficiency can be minimized by taking every precaution to preserve the AChA patency and intraoperative monitoring. In addition, the surgical outcome is primarily determined by the preoperative clinical state.     

Surgical Experience of the Ruptured Distal Anterior Cerebral Artery Aneurysms

Objective

Distal anterior cerebral artery (DACA) aneurysms are fragile and known to have high risks for intraoperative premature rupture and a relatively high associated morbidity. To improve surgical outcomes of DACA aneurysms, we reviewed our surgical strategy and its results postoperatively.

Methods

A total of 845 patients with ruptured cerebral aneurysms were operated in our hospital from January 1991 to December 2005. Twenty-three of 845 patients had ruptured DACA aneurysms which were operated on according to our surgical strategy. Our surgical strategy was as follows; early surgery, appropriate releasing of CSF, appropriate surgical approach, using neuronavigating system, securing the bridging veins, using temporary clipping and/or tentative clipping, meticulous manipulation of aneurysm, and using micro-Doppler flow probe. Twenty of 23 patients who had complete medical records were studied retrospectively. We observed the postoperative radiographic findings and checked Glasgow Outcome Scale score sixth months after the operation.

Results

Nineteen DACA aneurysms were clipped through a unilateral interhemispheric approach and one DACA aneurysm was clipped through a pterional approach. Postoperative radiographic findings revealed complete clipping of aneurysmal neck without stenosis or occlusion of parent arteries. In two patients, a residual neck of aneurysm was visualized. Seventeen patients showed good recovery, one patient resulted in moderate disability, while 2 patients died.

Conclusion

With our surgical strategy it was possible to achieve acceptable surgical morbidity and mortality rates in patients with DACA aneurysms. Appropriate use of tentative clipping, temporary clipping and neuro-navigating systems can give great help for safe approach and clipping of DACA aneurysm.     

Characteristics and Management of Residual or Slowly Recurred Intracranial Aneurysms

Objective

Residual aneurysm from incomplete clipping or slowly recurrent aneurysm is associated with high risk of subarachnoid hemorrhage. We describe complete treatment of the lesions by surgical clipping or endovascular treatment.

Methods

We analyzed 11 patients of residual or recurrent aneurysms who had undergone surgical clipping from 1998 to 2009. Among them, 5 cases were initially clipped at our hospital. The others were referred from other hospitals after clipping. The radiologic and medical records were retrospectively analyzed.

Results

All patients presented with subarachnoid hemorrhage at first time, and the most frequent location of the ruptured residual or recurrent aneurysm was in the anterior communicating artery to posterior-superior direction. Distal anterior cerebral artery, posterior communicating artery, and middle cerebral artery was followed. Repositioning of clipping in eleven cases, and one endovascular treatment were performed. No residual aneurysm was found in postoperative angiography, and no complication was noted in related to the operations.

Conclusion

These results indicate the importance of postoperative or follow up angiography and that reoperation of residual or slowly recurrent aneurysm should be tried if such lesions being found. Precise evaluation and appropriate planning including endovascular treatment should be performed for complete obliteration of the residual or recurrent aneurysm.     

Microsurgical clipping of previously coiled intracranial aneurysms

Objective

Endovascular coiling techniques for the treatment of intracranial aneurysms have rapidly developed as an alternative option to surgical clipping. A distinct problem after endovascular coiling is the management of a residual aneurysm neck due to incomplete filling, compaction of coils or regrowth of the aneurysm. Treatment options in this situation include surgical clipping, re-coiling, stent implantation or observation.

Methods

From June 2006 to August 2011, 15 patients underwent surgical clipping of residual or recurrent aneurysms after previous endovascular treatment. The mean age of the patients was 50.6 years (range, 27–85 years). The mean interval between coiling and clipping was 76.5 weeks (range, 0–288 weeks).

Results

Thirteen patients revealed a regrowth of coiled aneurysms, and in 5 patients compaction of coils was present. Coil extrusion was observed in 9 patients intraoperatively. In case of coil obstruction at the aneurysmal neck during surgery, coils were partially or completely removed. In all cases complete occlusion of the aneurysms was surgically achieved.

Conclusion

Coiled aneuryms with incomplete occlusion, coil compaction or regrowth of the aneurysmal neck can be successfully treated with microsurgical clipping. Coil extrusion was more often observed intraoperatively than expected. Complete occlusion of the aneurysm can be performed safely, even if loops of coils protrude into the aneurysmal neck. In these cases intraoperative removal of the coils enables secure closure of the aneurysm with a surgical clip.     

Unruptured Supraclinoid Internal Carotid Artery Aneurysm Surgery : Superciliary Keyhole Approach versus Pterional Approach

Objective

A superciliary keyhole approach is an attractive, minimally invasive surgical technique, yet the procedure is limited due to a small cranial opening. Nonetheless, an unruptured supraclinoid internal carotid artery (ICA) aneurysm can be an optimal surgical target of a superciliary approach as it is located in the center of the surgical view and field. Therefore, this study evaluated the feasibility and surgical outcomes of a superciliary keyhole approach for unruptured ICA aneurysms.

Methods

The authors report on a consecutive series of patients who underwent a superciliary approach for clipping unruptured ICA aneurysms between January 2007 and February 2012. The data were compared with a historical control group who underwent a pterional approach between January 2003 and December 2006.

Results

In the superciliary group, a total of 71 aneurysms were successfully clipped without a residual sac in 70 patients with a mean age of 57 years (range, 37-75 years). The maximum diameter of the aneurysms ranged from 4 mm to 14 mm (mean±standard deviation, 6.6±2.3 mm). No direct mortality or permanent morbidity was related to the surgery. The superciliary approach demonstrated statistically significant advantages over the pterional approach, including a shorter operative duration (mean, 100 min), no intraoperative blood transfusions, and no postoperative epidural hemorrhages.

Conclusion

A superciliary keyhole approach provides a sufficient surgical corridor to clip most unruptured supraclinoid ICA aneurysms in a minimally invasive manner.     

Internal Carotid Artery Reconstruction Using Multiple Fenestrated Clips for Complete Occlusion of Large Paraclinoid Aneurysms

Objective

Although surgical techniques for clipping paraclinoid aneurysms have evolved significantly in recent times, direct microsurgical clipping of large and giant paraclinoid aneurysms remains a formidable surgical challenge. We review here our surgical experiences in direct surgical clipping of large and giant paraclinoid aneurysms, especially in dealing with anterior clinoidectomy, distal dural ring resection, optic canal unroofing, clipping techniques, and surgical complications.

Methods

Between September 2001 and February 2012, we directly obliterated ten large and giant paraclinoid aneurysms. In all cases, tailored orbito-zygomatic craniotomies with extradural and/or intradural clinoidectomy were performed. The efficacy of surgical clipping was evaluated with postoperative digital subtraction angiography and computed tomographic angiography.

Results

Of the ten cases reported, five each were of ruptured and unruptured aneurysms. Five aneurysms occurred in the carotid cave, two in the superior hypophyseal artery, two in the intracavernous, and one in the posterior wall. The mean diameter of the aneurysms sac was 18.8 mm in the greatest dimension. All large and giant paraclinoid aneurysms were obliterated with direct neck clipping without bypass. With the exception of the one intracavenous aneurysm, all large and giant paraclinoid aneurysms were occluded completely.

Conclusion

The key features of successful surgical clipping of large and giant paraclinoid aneurysms include enhancing exposure of proximal neck of aneurysms, establishing proximal control, and completely obliterating aneurysms with minimal manipulation of the optic nerve. Our results suggest that internal carotid artery reconstruction using multiple fenestrated clips without bypass may potentially achieve complete occlusion of large paraclinoid aneurysms.     

Result of Extracranial-Intracranial Bypass Surgery in the Treatment of Complex Intracranial Aneurysms : Outcomes in 15 Cases

Objective

The standard treatment strategy of intracranial aneurysms includes either endovascular coiling or microsurgical clipping. In certain situations such as in giant or dissecting aneurysms, bypass surgery followed by proximal occlusion or trapping of parent artery is required.

Methods

The authors assessed the result of extracranial-intracranial (EC-IC) bypass surgery in the treatment of complex intracranial aneurysms in one institute between 2003 and 2007 retrospectively to propose its role as treatment modality. The outcomes of 15 patients with complex aneurysms treated during the last 5 years were reviewed. Six male and 9 female patients, aged 14 to 76 years, presented with symptoms related to hemorrhage in 6 cases, transient ischemic attack (TIA) in 2 unruptured cases, and permanent infarction in one, and compressive symptoms in 3 cases. Aneurysms were mainly in the internal carotid artery (ICA) in 11 cases, middle cerebral artery (MCA) in 2, posterior cerebral artery (PCA) in one and posterior inferior cerebellar artery (PICA) in one case.

Results

The types of aneurysms were 8 cases of large to giant size aneurysms, 5 cases of ICA blood blister-like aneurysms, one dissecting aneurysm, and one pseudoaneurysm related to trauma. High-flow bypass surgery was done in 6 cases with radial artery graft (RAG) in five and saphenous vein graft (SVG) in one. Low-flow bypass was done in nine cases using superficial temporal artery (STA) in eight and occipital artery (OA) in one case. Parent artery occlusion was performed with clipping in 9 patients, with coiling in 4, and with balloon plus coil in 1. Direct aneurysm clip was done in one case. The follow up period ranged from 2 to 48 months (mean 15.0 months). There was no mortality case. The long-term clinical outcome measured by Glasgow outcome scale (GOS) showed good or excellent outcome in 13/15. The overall surgery related morbidity was 20% (3/15) including 2 emergency bypass surgeries due to unexpected parent artery occlusion during direct clipping procedure. The short-term postoperative bypass graft patency rates were 100% but the long-term bypass patency rates were 86.7% (13/15). Nonetheless, there was no bypass surgery related morbidity due to occlusion of the graft.

Conclusion

Revascularization technique is a pivotal armament in managing complex aneurysms and scrupulous prior planning is essential to successful outcomes.     

Unruptured Intracranial Aneurysms with Oculomotor Nerve Palsy : Clinical Outcome between Surgical Clipping and Coil Embolization

Objective

To evaluate the clinical outcome of coil embolization for unruptured intracranial aneurysm (UIA) with oculomotor nerve palsy (ONP) compared with surgical clipping.

Methods

A total of 19 patients presented with ONP caused by UIAs between Jan 2004 and June 2008. Ten patients underwent coil embolization and nine patients surgical clipping. The following parameters were retrospectively analyzed to evaluate the differences in clinical outcome observed in both coil embolization and surgical clipping : 1) gender, 2) age, 3) location of the aneurysm, 4) duration of the symptom, and 5) degree of ONP.

Results

Following treatment, complete symptomatic recovery or partial relief from ONP was observed in 15 patients. Seven of the ten patients were treated by coil embolization, compared to eight of the nine patients treated by surgical clipping (p = 0.582). Patient''s gender, age, location of the aneurysm, size of the aneurysm, duration of symptom, and degree of the ONP did not statistically correlate with recovery of symptoms between the two groups. No significant differences were observed in mean improvement time in either group (55 days in coil embolization and 60 days in surgical clipping).

Conclusion

This study indicates that no significant differences were observed in the clinical outcome between coil embolization and surgical clipping techniques in the treatment of aneurysms causing ONP. Coil embolization seems to be more feasible and safe treatment modality for the relief and recovery of oculomotor nerve palsy.     

Anterior Communicating Artery Aneurysm Related to Visual Symptoms

Objective

Intracranial aneurysms are sometimes presented with visual symptoms by their rupture or direct compression of the optic nerve. It is because their prevalent sites are anatomically located close to the optic pathway. Anterior communicating artery is especially located in close proximity to optic nerve. Aneurysm arising in this area can produce visual symptoms according to their direction while the size is small. Clinical importance of visual symptoms presented by aneurysmal optic nerve compression is stressed in this study.

Methods

Retrospective analysis of ruptured anterior communicating artery aneurysms compressing optic apparatus were carried out. Total 33 cases were enrolled in this study. Optic nerve compression of the aneurysms was confirmed by the surgical fields.

Results

In 33 cases among 351 cases of ruptured anterior communicating artery aneurysms treated surgically, from 1991 to 2000, the dome of aneurysm was compressed in optic pathway. In some cases, aneurysm impacted into the optic nerve that deep hollowness was found when the aneurysm sac was removed during operation. Among 33 cases, 10 cases presented with preoperative visual symptoms, such as visual dimness (5), unilateral visual field defect (2) or unilateral visual loss (3), 20 cases had no visual symptoms. Visual symptoms could not be checked in 3 cases due to the poor mental state. In 6 cases among 20 cases having no visual symptoms, optic nerve was deeply compressed by the dome of aneurysm which was seen in the surgical field. Of 10 patients who had visual symptoms, 8 showed improvement in visual symptoms within 6 months after clipping of aneurysms. In 2 cases, the visual symptoms did not recover.

Conclusion

Anterior communicating artery aneurysm can cause visual symptoms by compressing the optic nerve or direct rupture to the optic nerve with focal hematoma formation. We emphasize that cerebral vascular study is highly recommended to detect intracranial aneurysm before its rupture in the case of normal CT findings with visual symptoms and frequent headache.     

Clinical and Angiographic Results after Treatment with Combined Clipping and Wrapping Technique for Intracranial Aneurysm

Objective

There have been numerous follow-up studies of patients who had ruptured or unruptured intracranial aneurysms treated by wrapping technique using various materials have been reported. Our objective was to ascertain whether our particular wrapping technique using the temporalis muscle provides protection from rebleeding and any aneurysm configuration changes in follow-up studies.

Methods

Clinical presentation, the location and shape of the aneurysm, outcomes at discharge and last follow-up, and any aneurysm configuration changes on last angiographic study were analyzed retrospectively in 21 patients. Reinforcement was acquired by clipping the wrapped temporalis muscle. Wrapping and clipping after incomplete clipping was also done. Follow-up loss and non-angiographic follow-up patient groups were excluded in this study.

Results

The mean age was 53 years (range 29-67), and 15 patients were female. Among 21 patients, 10 patients had ruptured aneurysms (48%). Aneurysms in 21 patients were located in the anterior circulation. Aneurysm shapes were broad neck form (14 cases), fusiform (1 case), and bleb to adjacent vessel (6 cases). Five patients were treated by clipping the wrapped temporalis, and 16 patients by wrapping after partial clipping. The mean Glasgow coma scale (GCS) at admission was 14.2. The mean Glasgow outcome scale (GOS) at discharge was 4.8, and 18 patients were grade 5. The mean period between initial angiography and last angiography was 18.5 months (range 8-44). Aneurysm size was not increased in any of these patients and configuration also did not change. There was no evidence of rebleeding in any of these treated aneurysms.

Conclusion

Our study results show that wrapping technique, using the temporalis muscle and aneurysm clip(s), for intracranial aneurysm treatment provides protection from rebleeding or regrowth.     

Risk of Shunt Dependent Hydrocephalus after Treatment of Ruptured Intracranial Aneurysms : Surgical Clipping versus Endovascular Coiling According to Fisher Grading System

Objective

The amount of hemorrhage observed on a brain computed tomography scan, or a patient''s Fisher grade (FG), is a powerful risk factor for development of shunt dependent hydrocephlaus (SDHC). However, the influence of treatment modality (clipping versus coiling) on the rate of SDHC development has not been thoroughly investigated. Therefore, we compared the risk of SDHC in both treatment groups according to the amount of subarachnoid hemorrhage (SAH).

Methods

We retrospectively reviewed 839 patients with aneurysmal SAH for a 5-year-period. Incidence of chronic SDHC was analyzed using each treatment modality according to the FG system. In addition, other well known risk factors for SDHC were also evaluated.

Results

According to our data, Hunt-Hess grade, FG, acute hydrocephalus, and intraventricular hemorrhage were significant risk factors for development of chronic SDHC. Coiling group showed lower incidence of SDHC in FG 2 patients, and clipping groups revealed a significantly lower rate in FG 4 patients.

Conclusion

Based on our data, treatment modality might have an influence on the incidence of SDHC. In FG 4 patients, the clipping group showed lower incidence of SDHC, and the coiling group showed lower incidence in FG 2 patients. We suggest that these findings could be a considerable factor when deciding on a treatment modality for aneurysmal SAH patients, particularly when the ruptured aneurysm can be occluded by either clipping or coiling.     

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.     

Surgical Treatment of Giant Serpentine Aneurysm of A2-A3 Segment Distal Anterior Cerebral Artery : Technical Case Report

Objective

To report our surgical experience using in situ end-to-side bypass for giant serpentine distal anterior cerebral artery aneurysm, unsuitable for microsurgical clipping.

Methods

A 49-year-old woman presented with headache and intermittent loss of consciousness. The brain computed tomography scan revealed a partially calcified mass in the interhemispheric fissure. On cerebral angiography, that was giant (30×18 mm sized), serpentine aneurysm originating from the A2 to A3 segment of the distal anterior cerebral artery (DACA). The aneurysm was trapped with clips, and the right A3 segment to left A3 segment of DACA, end-to-side in situ bypass was performed. Surgical result was favorable, with no newly developed ischemic event in the acute recovery period. Postoperative angiography showed total occlusion of the aneurysm and good patency, with preserved distal flow.

Conclusion

Giant fusiform aneurysms of the DACA are extremely rare and can be particularly challenging to treat. End-to-side A3 : A3 bypass with aneurysm trapping could be a treatment modality for these locations.     

What Should Be Considered to Cause the Early Post-Craniotomy Seizure: Antibiotics (Cefazolin) Irrigation

Objective

Post-craniotomy seizure (PCS) is reported only rarely. However, our department noted a 433% increase in PCS for a year beginning September 2010, especially after cerebrovascular surgery. Our goal was to identify the cause of our unusual outbreak of PCS.

Methods

For almost one year after September 2010, cases of PCS increased significantly in our department. We analyzed 973 patients who had received a major craniotomy between January 2009 and November 2011. We included seizures that occurred only in the first 24 postoperative hours, which we defined as early PCS. After verifying the presence of PCS, we analyzed multiple seizure-provoking factors and their relation to the duration and character of seizure activity.

Results

Overall PCS incidence was 7.2% (70/973). Cefazolin (2 g/L saline) was the antibiotic drug used for intraoperative irrigation in 88.4% of the operations, and no PCS occurred without intraoperative cefazolin irrigation. When analyzed by operation type, clipping surgery for unruptured aneurysms was the most frequently associated with PCS (80%). Using logistic regression, only 2 g cefazolin intraoperative irrigation (p=0.024) and unruptured aneurysm clipping surgery (p<0.001) were associated with early PCS. The seizure rate of unruptured aneurysm clipping surgery using 2 g cefazolin intraoperative irrigation was 32.9%.

Conclusion

Intraoperative cefazolin irrigation must be avoided in patients undergoing craniotomy, especially for clipping of unruptured aneurysms, because of the increased risk of early PCS.     

Comparison between Lateral Supraorbital Approach and Pterional Approach in the Surgical Treatment of Unruptured Intracranial Aneurysms

Objective

The lateral supraorbital (LSO) approach is a modified method of the classic pterional approach and it has advantages of short skin incision and small craniotomy compared with the pterional approach. This study was designed to compare the two approaches in the surgical treatment of unruptured intracranial aneurysms.

Methods

We retrospectively reviewed 122 patients with 137 unruptured intracranial aneurysms treated by clipping, from July 2009 to April 2011. Between August 2010 and April 2011, 61 patients were treated by clipping via the lateral supraorbital approach and the same number of patients treated by clipping via the pterional approach were retrospectively enrolled. We analyzed the two groups and compared demographic, radiologic and clinical variables.

Results

The mean age of patients in the two groups was 54.6 years (LSO group) and 55.7 years (Pterion group). The mean duration of hospitalization was shorter in the LSO group than in the Pterion group (7.9 days vs. 9.0 days, p=0.125) and the mean operation time was also significantly shorter in the LSO group (117.1 minutes vs. 164.3 minutes, p<0.001). Furthermore, the mean craniotomy area was much smaller in the LSO group (1275.4 mm² vs. 2858.9 mm², p<0.001). The two groups showed similar distributions of aneurysm location and postoperative complications.

Conclusion

The lateral supraorbital approach for the clipping of unruptured intracranial aneurysm could be a good alternative to the classic pterional approach.     

Feasibility and Efficacy of Olfactory Protection Using Gelfoam and Fibrin Glue during Anterior Communicating Artery Aneurysm Surgery

Objective

Patients treated with surgical clipping for anterior communicating artery (A-com) aneurysm often complain of anosmia, which can markedly impede their quality of life. We introduce a simple and useful technique to reduce postoperative olfactory dysfunction in A-com aneurysm surgery.

Methods

We retrospectively reviewed the medical records of patients who underwent surgical clipping for unruptured aneurysm from 2011-2013 by the same senior attending physician. Since March 2012, olfactory protection using gelfoam and fibrin glue was applied in A-com aneurysm surgery. Therefore we categorized patients in two groups from this time-protected group and unprotected group.

Results

Of the 63 enrolled patients, 16 patients showed postoperative olfactory dysfunction-including 8 anosmia patients (protected group : unprotected group=1 : 7) and 8 hyposmia patients (protected group : unprotected group=2 : 6). Thirty five patients who received olfactory protection during surgery showed a lower rate of anosmia (p=0.037, OR 10.516, 95% CI 1.159-95.449) and olfactory dysfunction (p=0.003, OR 8.693, 95% CI 2.138-35.356). Superior direction of the aneurysm was also associated with a risk of olfactory dysfunction (p=0.015, OR 5.535, 95% CI 1.390-22.039).

Conclusion

Superior direction of aneurysm appears associated with postoperative olfactory dysfunction. Olfactory protection using gelfoam and fibrin glue could be a simple, safe, and useful method to preserve olfactory function during A-com aneurysm surgery.     

Effect of Cisternal Drainage on the Shunt Dependency Following Aneurysmal Subarachnoid Hemorrhage

Objective

Shunt-dependent chronic hydrocephalus (SDCH) is known to be a major complication associated with aneurysmal subarachnoid hemorrhage (aSAH). Old age is known to be one of numerous factors related to the development of SDCH. This study investigated whether postoperative cisternal drainage affects the incidence of SDCH and clinical outcome in elderly patients with aSAH.

Methods

Fifty-nine patients participated in this study. All patients underwent aneurysmal clipping with cisternal cerebrospinal fluid (CSF) drainage. Clinical variables relevant to the study included age, sex, location of ruptured aneurysm, CT finding and clinical state on admission, clinical outcome, and CSF drainage. We first divided patients into two groups according to age (<70 years of age and ≥70 years of age) and compared the two groups. Secondly, we analyzed variables to find factors associated with SDCH in both groups (<70 years of age and ≥70 years of age).

Results

Of 59 patients, SDCH was observed in 20 patients (33.9 %), who underwent shunt placement for treatment of hydrocephalus. Forty seven percent of cases of acute hydrocephalus developed SDCH. In the elderly group (≥70 years of age), the duration and amount of CSF drainage did not affect the development of chronic hydrocephalus.

Conclusion

In elderly patients, although the incidence of SDCH was significantly higher, clinical outcome was acceptable. The duration and the amount of cisternal drainage did not seem to be related to subsequent development of chronic hydrocephalus within elderly patients aged 70 or older.     

Association between Ischemic Stroke and Vascular Shear Stress in the Carotid Artery

Background and Purpose

Vascular shear stress is essential for maintaining the morphology and function of endothelial cells. We hypothesized that shear stress in the internal carotid artery (ICA) may differ between patients with ischemic stroke and healthy control subjects.

Methods

ICA shear stress was calculated in 143 controls and 122 patients with ischemic stroke who had a normal ICA or an ICA with <50% stenosis. The stroke group included patients who presented with a first-ever or recurrent ischemic stroke but excluded cardioembolic stroke and uncertain etiologies. Of the 122 patients, 107 (87.7%) and 15 (12.3%) patients were categorized as first-ever and recurrent stroke, respectively.

Results

Carotid diameters were significantly larger, and both peak-systolic and end-diastolic velocities were significantly lower in patients with ischemic stroke than in controls (all p values <0.05). Mean values of peak-systolic and end-diastolic shear stress in both ICAs were significantly lower in patients with ischemic stroke in models that adjusted for age, sex, and vascular risk factors (p for trend <0.05). The ICA shear stress was lowest in patients with recurrent stroke or the subtype of small-vessel occlusion. Higher peak-systolic and end-diastolic shear stresses in both ICAs were independently and negatively associated with ischemic stroke after adjusting for potential confounders (all p values <0.05).

Conclusions

ICA shear stresses were significantly lower in patients with ischemic stroke than in control subjects. Future studies should attempt to define the causal relationship between carotid arterial shear stress and ischemic stroke.     

Brain Injuries during Intraoperative Ventriculostomy in the Aneurysmal Subarachnoid Hemorrhage Patients

Objective

Intraoperative ventriculostomy is widely adopted to make the slack brain. However, there are few reports about hemorrhagic or parenchymal injuries after ventriculostomy. We tried to analyze and investigate the incidence of these complications in a consecutive series of patients with aneurysmal subarachnoid hemorrhage (SAH).

Methods

From September 2006 to June 2007, 43 patients underwent surgical clipping for aneurysmal SAH at our hospital. Among 43 patients, we investigated hemorrhagic or parenchymal injuries after intraoperative ventriculostomy using postoperative computed tomographic scan in 26 patients. After standard pterional craniotomy, ventriculostomy catheter was inserted perpendicular to the cortical surface along the bisectional imaginary line from Paine''s point.

Results

Hemorrhagic injuries were detected in 12 of 26 patients (46.2%). Mean systolic blood pressure during anesthesia was with in statistically significant parameter related to hemorrhage (p = 0.006). On the other hand, parenchymal injuries were detected in 11 of 26 patients (42.3%). Female and the amount of infused mannitol during anesthesia showed statistically significant parameters related to parenchymal injury (p = 0.005, 0.04, respectively). However, there were no ventriculostomy-related severe complications.

Conclusion

In our series, hemorrhagic or parenchymal injuries after intraoperative ventriculostomy occurred more commonly than previously reported series in aneurysmal SAH patients. Although the clinical outcomes of complications are generally favorable, neurosurgeon must keep in mind the frequent occurrence of brain injury after intraoperative ventriculostomy in the acute stage of aneurysmal SAH.     

Superficial Temporal Artery to Anterior Cerebral Artery Hemi-bonnet Bypass Using Radial Artery Graft for Prevention of Complications after Surgical Treatment of Partially Thrombosed Large/Giant Anterior Cerebral Artery Aneurysm

Background

Partially thrombosed large/giant aneurysm of the anterior cerebral artery is still challenging because this complex aneurysm requires arterial revascularization in the deep operation field. Therefore, direct neck clipping is often impossible. We describe our experiences with extracranial-intracranial bypass as an insurance bypass prior to clipping of partially thrombosed anterior cerebral artery aneurysms, and discuss the microsurgical technique and strategy.