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Background Adequate bypass harvesting of the superficial temporal artery (STA) is a standard procedure for every neurosurgeon, so mastery of techniques for its management and care is mandatory. Methods Here, we report the effectiveness of using the bipolar forceps as a novel procedure. Results This procedure improves safety, efficiency, and bleeding compared to the usual dissection. Conclusions In cases requiring an STA donor, this technique may be as useful as the traditional method and could become part of the neurosurgeon's armamentarium.

Item does not contain fulltext IMPORTANCE: Unruptured intracranial aneurysms not undergoing preventive endovascular or neurosurgical treatment are often monitored radiologically to detect aneurysm growth, which is associated with an increase in risk of rupture. However, the absolute risk of aneurysm rupture after detection of growth remains unclear. OBJECTIVE: To determine the absolute risk of rupture of an aneurysm after detection of growth during follow-up and to develop a prediction model for rupture. DESIGN, SETTING, AND PARTICIPANTS: Individual patient data were obtained from 15 international cohorts. Patients 18 years and older who had follow-up imaging for at least 1 untreated unruptured intracranial aneurysm with growth detected at follow-up imaging and with 1 day or longer of follow-up after growth were included. Fusiform or arteriovenous malformation-related aneurysms were excluded. Of the 5166 eligible patients who had follow-up imaging for intracranial aneurysms, 4827 were excluded because no aneurysm growth was detected, and 27 were excluded because they had less than 1 day follow-up after detection of growth. EXPOSURES: All included aneurysms had growth, defined as 1 mm or greater increase in 1 direction at follow-up imaging. MAIN OUTCOMES AND MEASURES: The primary outcome was aneurysm rupture. The absolute risk of rupture was measured with the Kaplan-Meier estimate at 3 time points (6 months, 1 year, and 2 years) after initial growth. Cox proportional hazards regression was used to identify predictors of rupture after growth detection. RESULTS: A total of 312 patients were included (223 [71%] were women; mean [SD] age, 61 [12] years) with 329 aneurysms with growth. During 864 aneurysm-years of follow-up, 25 (7.6%) of these aneurysms ruptured. The absolute risk of rupture after growth was 2.9% (95% CI, 0.9-4.9) at 6 months, 4.3% (95% CI, 1.9-6.7) at 1 year, and 6.0% (95% CI, 2.9-9.1) at 2 years. In multivariable analyses, predictors of rupture were size (7 mm or larger hazard ratio, 3.1; 95% CI, 1.4-7.2), shape (irregular hazard ratio, 2.9; 95% CI, 1.3-6.5), and site (middle cerebral artery hazard ratio, 3.6; 95% CI, 0.8-16.3; anterior cerebral artery, posterior communicating artery, or posterior circulation hazard ratio, 2.8; 95% CI, 0.6-13.0). In the triple-S (size, site, shape) prediction model, the 1-year risk of rupture ranged from 2.1% to 10.6%. CONCLUSION AND RELEVANCE: Within 1 year after growth detection, rupture occurred in approximately 1 of 25 aneurysms. The triple-S risk prediction model can be used to estimate absolute risk of rupture for the initial period after detection of growth.

Background: Wall enhancement of intracranial saccular aneurysms in high-resolution magnetic resonance vessel wall imaging (MR-VWI) might indicate a ruptured aneurysm. Therefore, this study aimed to determine the diagnostic ability of wall enhancement to detect the ruptured aneurysms among multiple aneurysms. Methods: Patients with subarachnoid hemorrhage (SAH) and multiple intracranial aneurysms who underwent MR-VWI before craniotomy and clipping were included in the study. Three-dimensional T1-weighted fast spin-echo sequences were obtained before and after gadolinium injection. Aneurysm rupture was estimated based on the subarachnoid clot distribution, aneurysmal contours, and MR-VWI findings. We selectively performed surgical clipping and confirmed the rupture site intraoperatively. Results: Thirteen patients with SAH with 13 ruptured and 17 unruptured aneurysms were treated at out facility. The accuracy rate of rupture site diagnosis using MR-VWI was 69.2% (9/13 cases). Each unruptured aneurysm was equally or more strongly enhanced in the other four cases than the ruptured aneurysms. In three of the four unruptured aneurysms with positive MR-VWI findings, atherosclerosis of the aneurysmal wall was observed during simultaneous or elective clipping surgery. Further, clipping surgery was performed without intraoperative rupture in two cases with the help of MR-VWI findings. Conclusion: Correct diagnosis of the rupture site using MR-VWI alone was unreliable due to false positives caused by the wall enhancement of unruptured aneurysms with atherosclerosis. Therefore, ruptured aneurysms should be detected using more information in addition to MR-VWI images. MR-VWI may be advantageous to determine surgical strategies when managing patients with SAH and multiple aneurysms.

BACKGROUND Recurrent aneurysms after initial clipping have been discussed as an important issue in the surgical management of aneurysm. OBJECTIVE To report our experience with recurrent cerebral aneurysms after neck clipping and to discuss classification and recommended management. METHODS Aneurysm treatments from a single institution over a 20-year period were retrospectively reviewed. Twenty-three recurrent aneurysms in 23 patients were managed during the study period. Recurrent aneurysms were classified using the concepts of closure line and closure plane, as follows. Type 1: neck situated in an almost different site from the previous clip. Type 2: existing closure plane and reconstructive closure plane are almost the same. Type 3: existing closure plane and reconstructive closure plane cross (type 3a); in rare cases, the existing closure line is sufficiently distant from the neck (type 3b). Type 4: no reconstructive closure line is identifiable. RESULTS Nine patients presented with subarachnoid hemorrhage at recurrence. The mean interval to recurrence was 15.0 years. Management comprised clipping with elective subsequent old-clip removal (n = 7), clipping with preceding old-clip removal (n = 2), bypass occlusion (n = 1), coating (n = 1), combined surgery (n = 1), endovascular surgery (n = 4), and observation (n = 3). Therapeutic intervention was not indicated in 4 patients. Types 3a and 4 required more complex surgical procedures or coil embolization. Procedural complications were observed in 2 patients. CONCLUSION A small but definite propensity toward recurrence after neck clipping exists, and most recurrent aneurysms require some form of retreatment. The novel classification scheme may provide conceptual clarity and therapeutic guidance for decision making.

Since non-vitamin K antagonist oral anticoagulants (NOACs) were released for clinical use, many studies have investigated its effectiveness in stroke prevention. In this study, to determine whether or not there is a difference in outcome in secondary stroke prevention between warfarin and NOACs, patients with embolic stroke with newly prescribed anticoagulants were prospectively analyzed.Patients with acute ischemic stroke, who newly started anticoagulant therapy, were consecutively asked to participate in this study. Enrolled patients (76.3 ± 11.0 years old) were classified into warfarin (n = 48), dabigatran (n = 73), rivaroxaban (n = 49), and apixaban (n = 65). The outcome in 1 year was prospectively investigated at outpatient clinic or telephone interview. Recurrence of stroke and death was considered as the critical incidence.The prevalence of risk factors was not different among all medicines. Patients with dabigatran showed significantly younger onset age (P .001: 72.2 years old) and milder neurologic deficits than patients on other medicines (P .001). Cumulative incident rates were 7.1%, 15.3%, 19.0%, and 29.7% for dabigatran, apixaban, rivaroxaban, and warfarin, respectively. Dabigatran showed relatively better outcome compared with warfarin (P = .069) and rivaroxaban (P = .055). All patients on NOACs presented lower cumulative stroke recurrence compared with warfarin.Even in the situation of secondary stroke prevention, noninferiority of NOACs to warfarin might be demonstrated.

Background Posterior communicating artery (PCoA) aneurysms are among the most common aneurysms. Because blockage of the PCoA and perforators can cause adverse outcomes, occlusion of these arteries by surgical clipping should be avoided. The impact of factors on PCoA perforator infarction when using a distal transsylvian approach for PCoA aneurysms was examined. Methods A total of 183 patients underwent PCoA aneurysm clipping, excluding application of fenestrated clips. Patients were divided into 2 groups: patients with PCoA perforator infarction (infarction group) and patients without infarction (noninfarction group). Multiple factors were analyzed in the 2 groups. Results Twenty-two of the 183 patients (12.0%) showed perforator infarction, mainly on magnetic resonance imaging evaluation, resulting in permanent deficits in 2 patients (1.1%). The proportion of right-sided operations (86.4% vs. 53.4%; P = 0.005) and surgery for rupture (90.9% vs. 55.9%; P = 0.002) were significantly higher in the infarction group than in the noninfarction group. Aneurysms were significantly larger in the infarction group (8.4 ± 3.8 mm) than in the noninfarction group (6.3 ± 3.0 mm; P = 0.02). Ruptured status (odds ratio [OR], 7.35; P = 0.01), right side (OR, 5.19; P = 0.01), and aneurysm size (OR, 1.18; P = 0.02) remained independent predictors of perforator infarction on multivariate logistic regression analysis. Conclusions Ruptured status, right side, and large PCoA aneurysm were independent predictors of PCoA perforator infarction. Symptoms due to PCoA perforating infarction were mostly transient and rarely affected outcomes.

Background Temporary vessel occlusion of the parent artery is an essential technique for aneurysm surgery. Our aim was to clarify the safe time for temporary occlusion for aneurysm surgery, that is the "safe time duration" (STD), in which brain tissue exposed to ischemia will almost never fall into even the ischemic penumbra during temporary occlusion of the middle cerebral artery (MCA), and even transient postoperative motor impairment will be rare using intraoperative motor-evoked potentials (MEP). Methods Twenty-four patients underwent MCA aneurysm clipping surgery with MEP monitoring for 13 ruptured aneurysms and 11 unruptured aneurysms. The duration of vessel occlusion in patients without MEP changes was measured as the STD. Average STD was calculated as 95% confidence interval for the population mean using sample data from patients with MEP changes and patients without changes. Results All 24 patients received proximal flow control only. Five patients (20.8%) developed significant intraoperative MEP changes. Time to MEP change (i.e., STD) in these patients was 4.6 ± 2.1 min. In patients without MEP changes, STD was 2.7 ± 1.4 min. Average STD was thus 3.1 ± 0.7 min. Conclusions The 95% lower confidence limit for average STD was 2.4 min when applying temporary occlusion on the proximal side of the MCA. This STD resembled that previously reported for temporary proximal occlusion of the internal carotid artery.

A small part of the patients with subarachnoid hemorrhage (SAH) are not properly diagnosed until they suffer ischemic neurological deficits and/or rebleeding during vasospasm. We therefore investigated the clinical profile of such patients. We retrospectively analyzed 581 patients with aneurysmal SAH experienced in our institute between 2001 and 2009. Patient’s characteristics, presence and severity of headache before final diagnosis, imaging investigations they received, their World Federation of Neurological Surgeons (WFNS) grades at admission, the location of aneurysm, treatment, and outcome at discharge were investigated. Five patients were not correctly diagnosed until they presented neurological deficits due to vasospasm or experienced simultaneous rebleeding. Their mean age was 69.4, and all were female. Although all patients had a bad headache, they did not undergo any imaging examinations. Immediate coil embolization was performed for 2 patients, 1 died due to rupturing during embolization procedure. The other 3 were treated by open clipping surgery (2 delayed and 1 immediate). Four patients had some disability as a sequel, and their outcomes were significantly worse compared with 53 patients with SAH in WFNS Grade II. The patients with SAH who had not been properly diagnosed in the acute stage had a poor outcome. We should be very careful when we see patients complaining of severe headache.

Blood blister-like aneurysms are dangerous aneurysms with fragile walls arising from the supraclinoid internal carotid artery (ICA). Primary treatment of these aneurysms in the acute stage is challenging, due to the substantial risk of periprocedural bleeding. We describe a series of 4 patients who presented with ruptured blister-like aneurysm of the ICA and were treated with completion of extracranial-intracranial high-flow bypass followed by inspection and trapping of the aneurysm. All patients were treated in the acute stage, within 48 hours of bleeding. External carotid artery to proximal middle cerebral artery bypass with interposed radial artery (RA) graft was established followed by approach to the lesion and trapping of the parent vessels. The aneurysms in 3 patients ruptured during dissection of the lesion from the surrounding structures, but bleeding was easily controlled. RA grafts were patent in all patients and no postoperative symptomatic ischemic or hemorrhagic complications were encountered, resulting in excellent outcomes with modified Rankin scale scores of 0 at follow up after 3 months. Our present strategy for surgical treatment of blister-like aneurysms completely avoided the risk of devastating intraoperative hemorrhage, offering a most cautious strategy associated with minimal risk of intraoperative massive bleeding.

The concept of optimum closure line was applied to a series of 51 consecutive middle cerebral artery aneurysms (14 ruptured, 37 unruptured) in 41 patients, 16 men and 25 women aged 29-79 years (mean 59.1 years). Visual inspection through the operating microscope revealed 3 types of aneurysm based on the origin of the aneurysm: bifurcation type (n = 39), trunk type (n = 9), and combined type (n = 3). Clipping along the optimum closure line should restore the vascular structure to the original configuration. Combination clip techniques were useful to form a curved closure line. This technique requires adequate operative fields with dissection of the aneurysm and related arteries from the neighboring structures as far as possible. The closure line concept is helpful to decide how to apply clips for particular aneurysms to avoid risks of ischemic complication and future recurrence. Combination clip techniques are often necessary to match a curved closure line.

We provide intraoperative problems and their preventive measures during the pterional approach to the basilar top aneurysm. We focus on the surgical techniques to obtain a wider operative field through the pterional approach. The surgical difficulties depend on various factors, including the size, location, and direction of the basilar top aneurysm. In particular, the interrelationship between the location of the internal carotid artery and the basilar top aneurysm is an important factor to be fully assessed preoperatively.

A frontotemporal craniotomy is usually performed using a “keyhole,” made at the union of the zygomatic arch and frontal bone. Consequently, skull depression may occur postoperatively, leading to temporal area deformities and poor cosmetic results. To prevent these complications, we describe our technique for frontotemporal craniotomy using an osteotome to prevent cosmetic deformities. After the temporal muscle is dissected and reflected with the scalp flap, a total of 3 burr holes are made in the frontal and temporal bones. In the lateral greater wing of the sphenoid, where a keyhole is usually made, a bone incision is made anteriorly-posteriorly with an osteotome. The bone flap is lifted upward, and the osteotome is inserted from behind to continue the incision. At craniotomy closure, the bone flap is fixed using a cranial bone flap fixation clamp. This procedure involves almost no removal of frontal or inferior temporal bone, resulting in virtually no bone defect. The absence of skull depression or deformity in the temples postoperatively leads to excellent cosmetic results. Our technique for frontotemporal craniotomy using an osteotome does not create bone defects, and use of titanium clamps for bone flap fixation provides normal skull bone alignment. This procedure provides excellent postoperative cosmetic results.

Background: Internal trapping in which the dissecting aneurysm is occluded represents reliable treatment to prevent rebleeding of ruptured vertebral artery (VA) dissecting aneurysms. Various methods of internal trapping are available, but which is most appropriate for preventing both recanalization of the VA and procedural complications is unclear. Case Description: A 61-year-old male presented with subarachnoid hemorrhage caused by rupture of a left VA dissecting aneurysm. Only the dilated segment of the aneurysm was occluded by coil embolization. Sixteen days after embolization, angiography showed recanalization of the treated left VA with blood supplying the dilated segment of the aneurysm, which showed morphological change between just proximal to the coil mesh and just distal to a coil, and antegrade blood flow through this part. Pathological examination showed that the rupture site that had appeared to be the most dilated area on angiography was located just above the orifice of the entrance. However, we think that this case of ruptured aneurysm had an entrance into a pseudolumen that existed proximal to the dilated segment, with antegrade recanalization occurring through the pseudolumen with morphological change because of insufficient coil obliteration of the entrance in the first therapy. Conclusions: This case suggests that occlusion of both the proximal and dilated segments of a VA dissecting aneurysm will prevent recanalization, by ensuring that any entrance to a pseudolumen of the aneurysm is completely closed. Careful follow-up after internal trapping is important, since antegrade recanalization via a pseudolumen may occur in the acute stage.

Background: Intraoperative qualitative indocyanine green (ICG) angiography has been used in cerebrovascular surgery. Hyperperfusion may lead to neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. The purpose of this study is to quantitatively evaluate intraoperative cerebral perfusion using microscope-integrated dynamic ICG fluorescence analysis, and to assess whether this value predicts hyperperfusion syndrome (HPS) after STA-MCA anastomosis. Methods: Ten patients undergoing STA-MCA anastomosis due to unilateral major cerebral artery occlusive disease were included. Ten patients with normal cerebral perfusion served as controls. The ICG transit curve from six regions of interest (ROIs) on the cortex, corresponding to ROIs on positron emission tomography (PET) study, was recorded. Maximum intensity (IMAX), cerebral blood flow index (CBFi), rise time (RT), and time to peak (TTP) were evaluated. Results: RT/TTP, but not IMAX or CBFi, could differentiate between control and study subjects. RT/TTP correlated (|r| = 0.534-0.807; P < 0.01) with mean transit time (MTT)/MTT ratio in the ipsilateral to contralateral hemisphere by PET study. Bland–Altman analysis showed a wide limit of agreement between RT and MTT and between TTP and MTT. The ratio of RT before and after bypass procedures was significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.60 ± 0.032 and 0.80 ± 0.056, respectively; P = 0.017). The ratio of TTP was also significantly lower in patients with postoperative HPS than in patients without postoperative HPS (0.64 ± 0.081 and 0.85 ± 0.095, respectively; P = 0.017). Conclusions: Time-dependent intraoperative parameters from the ICG transit curve provide quantitative information regarding cerebral circulation time with quality and utility comparable to information obtained by PET. These parameters may help predict the occurrence of postoperative HPS.

The transoral transclival approach for the treatment of intradural lesions of the clivus is often associated with serious complications such as cerebrospinal fluid (CSF) leakage and meningitis. CSF pulse energy may be the most significant factor in CSF leakage and meningitis, but a bone baffle can block such CSF pulse energy. A 64-year-old female presented with sudden onset of severe headache. She had subarachnoidal hemorrhage due to a rupture of the vertebral-posterior inferior cerebellar artery aneurysm. A 66-year-old female complaining of occipitalgia and numbness of the extremities had a foramen magnum meningioma. Both patients were treated via the transoral transclival route with a protective bone baffle, obtained from the iliac bone, securely fixed in the bone window to protect the repaired dura from injury by CSF pulse energy. Neither patient showed CSF leakage or meningitis, and the period of continuous lumbar CSF drainage was only 7 days. The transoral transclival approach with a bone baffle is still very effective in selected cases.

A 21-year-old male presented with temporal lobe epilepsy associated with a venous angioma in the ipsilateral frontal lobe, presenting as intractable complex partial seizures. Neuroimaging showed a cerebral venous angioma in the right dorsolateral and opercular frontal lobe, and atrophy of the right hippocampus. As the ictal electroencephalogram (EEG) obtained with subdural electrodes indicated spike discharges initiating from the right mesial temporal lobe, temporal lobectomy was performed. The patient was seizure-free after the operation. Patients with epilepsy who have a cerebral venous angioma require precise analysis of the seizure pattern and an ictal EEG because of cerebral venous angioma may be associated with an another epileptogenic lesion which is surgically treatable.

Background: Some patients require a second surgical intervention for recurrence of treated aneurysms, untreated aneurysms in patients with multiple lesions, or de novo aneurysm. This retrospective review of the data was undertaken to evaluate when retreatment is necessary after initial aneurysm treatment. Methods: Cerebral aneurysms in 1755 patients were treated via clipping or coiling between January 1995 and September 2012. Postoperative follow-up was performed at 6 months after treatment and was repeated every 12 months (or longer) after treatment using three-dimensional computed tomography angiography or magnetic resonance angiography. Results: A cumulative total of 156 patients (8.9%) (117 women, 39 men; mean age: 55.0 years; range: 25–79 years) needed retreatment for rupture or regrowth of aneurysm (n = 31; ruptured (R)/remaining unruptured (U), 26/5), formation of de novo aneurysm (n = 45; R/U, 23/22), known untreated aneurysm in patients with multiple lesions (n = 78; R/U, 5/73), and hemorrhage from undetected aneurysm (n = 2). The regrowth risk is higher after endovascular treatment than after craniotomy and clipping. Median time to retreatment was 187 months (range: 11–280 months) for regrowth, 165 months (range: 22–330 months) for de novo, and 24 months (range: 2.8–417 months) for known untreated aneurysm. Regrowth or known with subarachnoid hemorrhage were frequently treated within 2 years from initial treatment. Conclusions: Aneurysms with residua or untreated aneurysms in patients with multiple lesions carry a risk of bleeding during a relatively short period, whereas there is a small but significant risk of de novo formation and subsequent hemorrhage at over 10 years after previous treatment.

BACKGROUND AND IMPORTANCE We report a rare case of pathologically confirmed cryptic vascular malformation as a cause of primary convexity subarachnoid hemorrhage (SAH) of unknown etiology. CLINICAL PRESENTATION A 48-year-old woman presented with sudden severe headache. Localized right convexity SAH was observed on computed tomography (CT) scan, but the origin could not be detected despite extensive workup covering the entire head by using 3.0-Tesla magnetic resonance (MR) imaging with MR angiography and CT angiography combined with venous-phase imaging with a 320-detector row CT scanner. Subsequent digital subtraction angiography (DSA) performed 2.5 hours after admission failed to reveal any cause of SAH; however, a right frontoparietal avascular region was suspected to be due to a newly developed intracerebral hematoma. The lesion was simultaneously confirmed by angiographic cone-beam CT imaging. Because she remained neurologically intact, we decided to perform a follow-up study later with medical management. However, she developed left hemiparesis 3 hours after DSA. CT scan demonstrated progression of the hematoma, and her symptoms gradually worsened. Emergent surgical exploration along the SAH superficial to the postcentral sulcus and hematoma evacuation were performed, with favorable functional outcome. Pathological examination confirmed cryptic vascular malformation with several abnormally dilated arterioles within the subarachnoid space surrounded by a thick SAH clot. CONCLUSION It is important to consider the possibility of ruptured cryptic vascular malformation as a cause of nontraumatic nonaneurysmal convexity SAH when recurrent hemorrhage occurs despite thorough diagnostic workup, because surgical resection may be the only curative treatment option to eliminate the risk of rebleeding and disabling symptoms.

Background: Several de novo intracranial aneurysms have been described related to changes in hemodynamics after therapeutic occlusion of internal carotid artery (ICA); however, de novo aneurysms related to a supraclinoid arteriosclerotic stenosis of the ICA have not been described yet. Authors consider that it is important to bear in mind the possibility of developing an aneurysm in these special conditions. Case Description: The evolution of a 62-year-old patient with subarachnoid hemorrhage, intraparenchymal frontal hematoma with some atypical circumstances that were presented together as well as the treatment he received are shown in this report. We can see this patient suffered a right thalamic hemorrhage at the age of 51 years; this condition was associated to a severe atherosclerotic stenosis of right supraclinoid ICAy. A long term had elapsed since the diagnosis of the stenosis and the discovery of a ruptured ipsilateral de novo supraclinoid internal carotid artery-posterior communicating artery (ICA-PcomA) aneurysm. Conclusions: It seems like both conditions: the atherosclerotic supraclinoid ICA which tells of an Samano et at : Ruptured De Novo PcomA Aneurysm Associated with Arteriosclerotic Stenosis of Supraclinoid ICA. Altered vessel environment coupled to a long exposure time, hemodynamic changes, unbalance in the wall sheer stress could all of them lead to the development of the de novo aneurysm.

The present study aimed to evaluate the impact of early surgical evacuation of sylvian hematoma caused by ruptured middle cerebral artery (MCA) aneurysm on clinical outcome after subarachnoid hemorrhage. Hospital records and computed tomography scans for 26 patients with MCA aneurysm who underwent surgical clipping between June 2001 and January 2008 were retrospectively reviewed. All patients presented with sylvian hematoma associated with subarachnoid hemorrhage and received surgery at 7.9 +/- 3.6 (mean +/- standard deviation) hours of ictus. They were divided postoperatively into two groups, achievement (n = 16) and non-achievement (n = 10) of extensive hematoma evacuation, and their clinical course and functional outcomes were compared. The frequencies of delayed ischemic neurological deficit and vasospasm-related cerebral infarction were significantly less (p < 0.05) in the achievement group. Better functional outcomes were obtained in patients with successful evacuation (p < 0.05), as assessed by improvement of hemiparesis on manual muscle testing scale at postoperative 1-month follow up and by the modified Rankin scale at postoperative 3 and 6 months. Clinical outcomes were also better in the achievement group. These results suggest that better clinical course and outcome can be expected in patients who undergo early successful hematoma evacuation with surgical clipping of a ruptured MCA aneurysm.

Objective Although the necessity of craniotomy for an unruptured cerebral aneurysm (UCA) is controversial, surgery is warranted if surgical risks are less than the risks of natural history. In this study, we investigated the need for craniotomy for UCAs on the basis of surgical risk. Methods History of cerebrovascular disorders, aneurysm site and size, surgical complications, and clinical outcome were investigated in 368 patients (134 men, 234 women; ages 31-79 yr) who underwent craniotomy for treatment of UCA at our institute between 1993 and 2000. Results We investigated 549 aneurysms. The mean size was 6.0 mm. Sites affected were the anterior cerebral artery (101 aneurysms), internal carotid artery (224 aneurysms), middle cerebral artery (201 aneurysms), and vertebrobasilar artery (23 aneurysms). The most common previous cerebrovascular disorders were subarachnoid hemorrhage (58 patients, 15.8%) and cerebral infarction (41 patients, 11.1%). Eight patients experienced permanent neurological deficits, for a total morbidity of 2.2%. One patient died, for a total mortality of 0.3%. For UCAs less than 10 mm in size, the morbidity was 0.6% and the mortality was 0%. For UCAs greater than 10 mm in size, the morbidity was 6.1% and the mortality was 1.2%. For UCAs in the anterior cerebral artery or middle cerebral artery, the morbidity was 0.3%. Temporary deficits were more frequently observed in patients older than 70 years of age than in patients 70 years of age or less. Conclusion Surgical treatment is a viable alternative for patients 70 years of age or less with UCAs less than 10 mm in size or UCAs located in the anterior cerebral artery or middle cerebral artery, because the surgical risk of treating such UCAs is sufficiently lower than the annual rupture rate of UCAs (2.3%) and the mental stress suffered by patients with untreated UCAs.

Most recurrences of intracranial pure germinoma occur at the primary site, ventricular wall or subarachnoid space. We report a rare case of intracranial germinoma that recurred along the shunt tube 17 years after prior ventriculoperitoneal shunt and radiotherapy. The recurrent tumor, verified histologically as a pure germinoma, involved the right frontal lobe along the ventricular catheter. In spite of subsequent surgery, radiation and chemotherapy, the tumor recurred repeatedly. Recurrence after such a long period highlights the necessity of long-term follow up for patients with germinoma. We also discuss possible causes of tumor dissemination along the ventricular catheter.

Background The study aims were to clarify safe duration for temporary vessel occlusion of the internal carotid artery (ICA) during aneurysm surgery as exactly as possible. We examined safe time duration (STD), where brain tissue exposed to ischemia will never fall into even the ischemic penumbra using intraoperative motor-evoked potential (MEP). Methods In 45 patients, temporary occlusion of the ICA was performed with MEP. We measured STD as the duration of temporary vessel occlusion during which MEP changes did not occur. To estimate average STD, we calculated the 95% confidence interval for the population mean from sample data for STD in patients with MEP changes and in patients without changes. Results In the proximal-control group, 4 of 38 patients (10.5%) developed intraoperative MEP changes. In 4 patients, the time to MEP change (i.e. STD) was 6.0 ± 2.5 min. STD was 3.8 ± 1.6 min in the 34 patients without changes. The average STD was 4.0 ± 0.6 min. In the trap group (proximal and distal flow control), five of seven patients (60.0%) experienced intraoperative MEP changes (STD, 2.3 ± 1.0 min). All patients in the trap group who developed MEP changes showed involvement of the anterior choroidal artery (AchA) in the trapped segment. Average STD was 2.3 ± 1.1 min when trapping involving the AchA. Conclusions Although the study is preliminary based on the limited number of the patients, the 95% upper confidence limit for average STD was 4.6 min when the ICA was occluded proximal to the aneurysm, 3.4 min when the ICA was trapped involving the AchA.