Rationale for graft selection in patients with complex internal carotid artery aneurysms treated with extracranial to intracranial high-flow bypass and therapeutic internal carotid artery occlusion.

OBJECTIVE After internal carotid artery (ICA) sacrifice without revascularization for complex aneurysms, ischemic complications can occur. In addition, hemodynamic alterations in the circle of Willis create conditions conducive to the formation of de novo aneurysms or the enlargement of existing untreated aneurysms. Therefore, the revascularization technique remains indispensable. Because vessel sizes and the development of collateral circulation are different in each patient, the ideal graft size to prevent low flow-related ischemic complications (LRICs) in external carotid artery (ECA)-middle cerebral artery (MCA) bypass with therapeutic ICA occlusion (ICAO) has not been well established. Authors of this study hypothesized that the adequate graft size could be calculated from the size of the sacrificed ICA and the values of MCA pressure (MCAP) and undertook an investigation in patients with complex ICA aneurysms treated with ECA-graft-MCA bypass and therapeutic ICAO. METHODS In the period between July 2006 and January 2016, 80 patients with complex ICA aneurysms were treated with ECA-MCA bypass and therapeutic ICAO. Preoperative balloon test occlusion (BTO) was performed, and the BTO pressure ratio was defined as the mean stump pressure/mean preocclusion pressure. Low flow-related ischemic complications were defined as new postoperative neurological deficits and ipsilateral cerebral blood flow reduction. Initial MCAP (iMCAP), MCAP after clamping the ICA (cMCAP), and MCAP after releasing the graft (gMCAP) were intraoperatively monitored. The MCAP ratio was defined as gMCAP/iMCAP. Based on the Hagen-Poiseuille law, the expected MCAP ratio ([expected gMCAP]/iMCAP) was hypothesized as follows: (1 - cMCAP/iMCAP)(graft radius/ICA radius)2 + (cMCAP/iMCAP). Correlations between the BTO pressure ratio and cMCAP/iMCAP, and between the actual and expected MCAP ratios, were evaluated. Risk factors for LRICs were also evaluated. RESULTS The mean BTO pressure ratio was significantly correlated with the mean cMCAP/iMCAP (r = 0.68, p < 0.0001). The actual MCAP ratio correlated with the expected MCAP ratio (r = 0.43, p < 0.0001). If the expected MCAP ratio was set up using the BTO pressure ratio instead of cMCAP/iMCAP (BTO-expected MCAP ratio), the mean BTO-expected MCAP ratio significantly correlated with the expected MCAP ratio (r = 0.95, p < 0.0001). During a median follow-up period of 26.1 months, LRICs were observed in 9 patients (11%). An actual MCAP ratio < 0.80 (p = 0.003), expected MCAP ratio < 0.80 (p = 0.001), and (M2 radius/graft radius)2 < 0.49 (p = 0.002) were related to LRICs according to the Cox proportional-hazards model. CONCLUSIONS Data in the present study indicated that it was important to use an adequate graft to achieve a sufficient MCAP ratio in order to avoid LRICs and that the adequate graft size could be evaluated based on a formula in patients with complex ICA aneurysms treated with ICAO.

Subarachnoid hemorrhage after surgical treatment of unruptured intracranial aneurysms.

OBJECTIVE Only a few previous studies have investigated subarachnoid hemorrhage (SAH) after surgical treatment in patients with unruptured intracranial aneurysms (UIAs). Given the improvement in long-term outcomes of embolization, more extensive data are needed concerning the true rupture rates after microsurgery in order to provide reliable information for treatment decisions. The purpose of this study was to investigate the incidence of and risk factors for postoperative SAH in patients with surgically treated UIAs. METHODS Data from 702 consecutive patients harboring 852 surgically treated UIAs were evaluated. Surgical treatments included neck clipping (complete or incomplete), coating/wrapping, trapping, proximal occlusion, and bypass surgery. Clippable UIAs were defined as UIAs treated by complete neck clipping. The annual incidence of postoperative SAH and risk factors for SAH were studied using Kaplan-Meier survival analysis and Cox proportional hazards regression models. RESULTS The patients' median age was 64 years (interquartile range [IQR] 56-71 years). Of 852 UIAs, 767 were clippable and 85 were not. The mean duration of follow-up was 731 days (SD 380 days). During 1708 aneurysm years, there were 4 episodes of SAH, giving an overall average annual incidence rate of 0.23% (95% CI 0.12%-0.59%) and an average annual incidence rate of 0.065% (95% CI 0.0017%-0.37%) for clippable UIAs (1 episode of SAH, 1552 aneurysm-years). Basilar artery location (adjusted hazard ratio [HR] 23, 95% CI 2.0-255, p = 0.0012) and unclippable UIA status (adjusted HR 15, 95% CI 1.1-215, p = 0.046) were significantly related to postoperative SAH. An excellent outcome (modified Rankin Scale score of 0 or 1) was achieved in 816 (95.7%) of 852 cases overall and in 748 (98%) of 767 clippable UIAs at 12 months. CONCLUSIONS In this large case series, microsurgical treatment of UIAs was found to be safe and effective. Aneurysm location and unclippable morphologies were related to postoperative SAH in patients with surgically treated UIAs.

Posterior Inferior Cerebellar Artery Thrombosed Aneurysm Associated with Persistent Primitive Hypoglossal Artery Successfully Treated with Condylar Fossa Approach.

A 68-year-old woman presented with generalized seizure due to the left internal carotid artery (ICA) aneurysmal compression of the ipsilateral medial temporal lobe. Computed tomography angiography (CTA) revealed multiple aneurysms of the right persistent primitive hypoglossal artery (PPHA), the right ICA, and the right anterior cerebral artery (ACA). The right PPHA originated from the ICA at the level of the C1 and C2 vertebral bodies and passed through the hypoglossal canal (HC). The PPHA aneurysm was large and thrombosed, which was located at the bifurcation of the right PPHA and the right posterior inferior cerebellar artery (PICA), projecting medially to compress the medulla oblongata. Since this patient had no neurological deficits, sequential imaging studies were performed to follow this lesion, which showed gradual growth of the PPHA aneurysm with further compression of the brain stem. Although the patient remained neurologically intact, considering the growing tendency clipping of the aneurysm was performed. Drilling of the condylar fossa was necessary to expose the proximal portion of the PPHA inside the HC. The key of this surgery was the preoperative imaging studies to fully understand the anatomical structures. The PPHA was fully exposed from the dura to the corner its turning inferiorly without damaging the occipital condylar facet. Utilizing this technique, the neck ligation of the aneurysm was safely achieved without any surgical complications.

Preventing Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage with Aggressive Cisternal Clot Removal and Nicardipine.

BACKGROUND: A subarachnoid clot is the strongest predictor of cerebral vasospasm. Our purpose was to analyze the relationship between the number of postoperative cisternal clots and cerebral vasospasm and to assess the efficacy of surgical clot removal. METHODS: The subjects were 158 patients with aneurysmal subarachnoid hemorrhage. All patients underwent clipping with cisternal clot removal. The preoperative and postoperative number of clots was analyzed semiquantitatively using computed tomography, and cerebral vasospasm and its severity were analyzed using magnetic resonance angiography in a blind fashion. Factors related to cerebral vasospasm and poor outcome were analyzed retrospectively. Poor outcome was defined as modified Rankin Scale (mRS) score of 3 or greater. RESULTS: Symptomatic cerebral vasospasm (SCV) was observed in 6 patients (3.8%). Angiographic vasospasm (AVS) was observed in 38 patients (24.1%). One year after the operation, 82.9% of patients had an mRS score of 0-2. The postoperative number of clots was significantly (P < 0.005) related to SCV (adjusted odds ratio [OR], 6.447; 95% confidence interval [CI], 2.063-20.146), AVS (OR, 2.634; 95% CI, 1.467-4.728), and poor outcome (OR, 2.103; 95% CI, 1.104-4.007). Poor outcome was also related to age over 65 (OR, 6.658; 95% CI, 2.389-18.559) and World Federation of Neurosurgical Societies scale grade (OR, 1.732; 95% CI, 1.248-2.403). CONCLUSIONS: Surgically removing as many clots as possible in the acute stage can decrease SCV and reduce AVS severity. Irrigation should be performed on all approachable cisterns.

Surgical treatment of unruptured distal basilar artery aneurysm: durability and risk factors for neurological worsening.

BACKGROUND: Distal basilar artery aneurysms (DBAs) consist of basilar apex and basilar artery-superior cerebellar artery bifurcation (BA-SCA) aneurysms. The authors aimed to investigate clinical and radiological differences between two locations and to evaluate the 12-month surgical outcome in unruptured DBAs. METHODS: Fifty-six consecutive patients who underwent surgical treatment (37 basilar apex and 19 BA-SCA aneurysms) between April 2012 and February 2016 were retrospectively evaluated. In patients with a preoperative modified Rankin Scale score (mRS) of more than 1, neurological worsening (NW) was defined as an increase in one or more mRS. In patients without symptoms, NW was defined as mRS ≥2. RESULTS: The mean age of the patient population was 64 ± 9.6 years, and 48 (86%) were female. Mean follow-up period was 2.6 ± 0.94 years. An excellent (mRS 0 to 1) outcome was archived in 31 (55%), 45 (82%), and 48 (87%) patients at 30 days, 6 months, and 12 months, respectively. Clinical and radiological characteristics showed no differences between two locations. One early death (1.8%) and one severe morbidity (1.8%) due to rupture were observed. The postoperative annual rupture rate was 1.4% overall (145 patient-years). After adjustment for age and location, large or giant DBA was related to 30-day and 12-month NW [n = 22 (39%) and n = 6 (11%); p = 0.009 and 0.002, respectively], aneurysm localization in the interpeduncular cistern (LIC) and perforator territory infarction were related to 30-day NW (p = 0.002 and 0.002), and DBA that needed bypass surgery and previously treated recurrent DBA were related to NW at 12 months (p = 0.017 and 0.001). Multivariate analysis showed that LIC was significantly related to perforator territory infarction (p = 0.003). CONCLUSIONS: Clinical and radiological characteristics were not different between basilar apex and BA-SCA aneurysms; therefore, they should not be discussed separately. To avoid neurological worsening, results of surgical treatment for unruptured DBAs should be improved.

Surgical Microanatomy of the Posterior Condylar Emissary Vein and its Anatomical Variations for the Transcondylar Fossa Approach.

BACKGROUND: It is essential to identify and be aware of the anatomy of the posterior condylar emissary vein (PCEV) for achieving an adequate operative field for the transcondylar fossa approach (TCFA). OBJECTIVE: To describe the variations in the drainage patterns of PCEVs and the technical issues encountered in such cases. METHODS: This was a retrospective analysis of the anatomy of PCEVs in 104 sides in 52 cases treated by the TCFA. Preoperative findings of multidetector-row computed tomography (CT) and CT venography (CTV) were compared with the intraoperative findings. The drainage patterns were classified as 5 types: the sigmoid sinus (SS), jugular bulb (JB), occipital sinus (OS), anterior condylar emissary vein (ACEV), and marginal sinus (MS). RESULTS: The SS, JB, ACEV, and OS types were observed in 33 (31.7%), 42 (40.3%), 8 (7.7%), and 1 (1.0%) side(s), respectively. One side (1.0%) each had combined drainage from MS and JB, and ACEV and JB, respectively. In 17 sides (16.3%), the PCEVs and posterior condylar canals could not be identified on CT and CTV. CONCLUSIONS: Preoperative CT and CTV findings correlated well with the intraoperative findings. To make a sufficient operative field for TCFA, PCEVs should be appropriately dealt with based on the preoperative knowledge of their running course, pattern, and origin.

Graft Occlusion and Graft Size Changes in Complex Internal Carotid Artery Aneurysm Treated by Extracranial to Intracranial Bypass Using High-Flow Grafts with Therapeutic Internal Carotid Artery Occlusion.

BACKGROUND: Although the extracranial-to-intracranial high-flow bypass (EC-IC HFB) continues to be indispensable for complex aneurysms, the risk factors for the graft occlusion and whether the graft size changes after the bypass have not been well established. OBJECTIVE: To evaluate the risk factors for the graft occlusion and to confirm whether graft diameters changed over time. METHODS: The data of 75 patients who suffered from complex internal carotid artery (ICA) aneurysms and were treated by EC-IC HFB using radial artery graft (RAG) or saphenous vein graft (SVG) with therapeutic ICA occlusion were evaluated. Clinical and radiological characteristics were compared in patients with and without the graft occlusion by the log-rank test. Graft diameters measured preoperatively, postoperatively, at 6 months, and at 1 year were compared by paired t-test. RESULTS: During a follow-up period (median 26.2 months), graft occlusions were seen in 4 patients (5.3%), and these were the SVGs. Only SVG was related to graft occlusion (P < .001). There was a significant increase with time in RAG diameters (preoperative, 3.1 ± 0.41 mm; postoperative, 3.6 ± 0.65 mm; 6 months, 4.3 ± 1.0 mm; 1 year, 4.4 ± 1.0 mm), while there were no significant diameter changes in SVGs. CONCLUSION: The present study showed that the SVG was related to the graft occlusion and RAGs gradually enlarged. Unless Allen test is negative, RAG may be better to be used as a graft in EC-IC HFB if therapeutic ICA occlusion is needed.

Impacts of pressure bonding fixation on a bone flap depression and resorption in patients with craniotomy.

Fixation of bone flaps after craniotomy is a routine part of every neurosurgical procedure. Common problems encountered are bone flap depression and resorption. Authors performed the pressure-bonding bone flap fixation (PBFF) using absorbable craniofix (AC) and hydroxyapatite wedge (HW). The aim of the present study is to evaluate the efficacy of PBFF to prevent a bone flap depression and resorption in patients treated with craniotomy. Four-hundred fifty-four patients underwent craniotomies. Authors collected the following data: age, sex, type of craniotomy, what kind of surgery, whether bypass surgery was performed, whether surgery was the initial, whether AC and the HW were used, bone flap depression and resorption at 6-month after the craniotomy. PBFF was defined as a bone flap fixation using both AC and HW to impress a bone flap to forehead. The mean age was 62±13years and 404 (89%) patients were women. PBFF was performed in 71 patients (16%), either AC or HW was used in 141 (31%), only AC was used in 116 (25%), and only HW was used in 25 (5.5%). At 6-month after the surgery, a bone flap depression was seen in 38 patients (8.4%), and a bone flap resorption was seen in 66 (15%). Multivariate analysis showed that only a PBBF showed a negative correlation with bone flap depression (p=0.044) and resorption (p=0.011). The results of the present study showed that PBFF reduced a bone flap depression and resorption and provided excellent postoperative cosmetic results.

A Contralateral Transcondylar Fossa Approach with Bilateral V3 Segment Exposure for Repairing Complex Vertebral Artery Aneurysms.

BACKGROUND AND IMPORTANCE: Microsurgical treatment for vertebral artery aneurysms can be approached through the lateral aspect of the brainstem and cerebellum. A contralateral approach may be selected in complex aneurysms with tortuous running and the intracranial vertebral artery distal to the aneurysm located in the contralateral cerebellopontine angle. When repairing the aneurysm, exposing the V3 segment before craniotomy is advantageous. We describe the detailed surgical procedures of the contralateral transcondylar fossa approach with bilateral V3 segment exposure for the repair of a complex vertebral artery aneurysm. CLINICAL PRESENTATION: A 48-year-old woman presented with a 23-mm unruptured thrombosed fusiform aneurysm in the right vertebral artery. The aneurysm and the V4 segment distal to it deviated to the left, and the aneurysm was compressing the left anterior aspect of the medulla oblongata. We treated the patient with trapping and thrombectomy, using a contralateral transcondylar fossa approach with bilateral V3 exposure. During the procedure, proximal vascular control was achieved by occluding the contralateral V3 segment and distal control was achieved by occluding the V4 segment. The aneurysm was successfully trapped and decompressed. The patient's postoperative course was good and she was discharged with a modified Rankin Scale score of 0. CONCLUSIONS: The contralateral transcondylar fossa approach with bilateral V3 exposure is feasible for the repair of complex vertebral artery aneurysms showing a deviated and difficult to access V4 segment proximal to the aneurysm. Bilateral V3 exposure may also facilitate aneurysm bypass procedures such as those using a V3-V4 anastomosis.

Surgical case of intracranial osteoma arising from the falx.

Intracranial osteomas completely unrelated to osseous tissues are extremely rare. In the present study, the case of a 40-year-old female who presented with persistent headache is reported. Computed tomography (CT) and bone window CT revealed an ossified lesion in the frontal area. Fast imaging employing steady-state acquisition (FIESTA)/CT venography fusion imaging demonstrated that the mass was located just below the superior sagittal sinus and cortical veins, and had adhered partially to these veins. Surgery achieved complete tumor removal with preservation of the cortical veins and superior sagittal sinus. The histological examination findings were compatible with osteoma. The present postoperative course was uneventful. The present rare case of intracranial osteoma originating from the falx was successfully treated surgically. Preoperative FIESTA/CT venography fusion imaging was very useful to demonstrate adhesion between the tumor mass and the superior sagittal sinus and cortical veins.

Bypass Revascularization Applied to the Posterior Cerebral Artery.

BACKGROUND: The application of bypass procedures to the posterior cerebral artery (PCA) in combination with proximal clipping or trapping is a useful option for the treatment of complex posterior circulation aneurysms, especially those of the PCA. Because of its course around the midbrain through various cisterns, different approaches are required to access the PCA. OBJECTIVE: The presented study analyzes a retrospective case series of bypass procedures to the PCA to investigate the relevant treatment strategies and their outcomes. METHODS: Seven patients with bypass procedures to the PCA bypass were analyzed. The location of the aneurysms, approaches, site of anastomosis, bypass patency, pre- and postoperative modified Rankin Scale scores, and transient and permanent morbidity were assessed. RESULTS: Analyzed patients were treated for intracranial aneurysm located on the P2 (n = 3) or P3 (n = 2) of the PCA, bilateral vertebral artery dissecting aneurysm (n = 1) or internal carotid artery-posterior communicating artery aneurysm (n = 1). The following approaches were used: anterior temporal approach (n = 2), anterior temporal approach combined with subtemporal approach (n = 2), combined transpetrosal approach (n = 1), posterior interhemispheric approach (n = 1), and posterior interhemispheric approach with subtemporal approach (n = 1). All bypasses were patent. Permanent morbidity occurred in 2 patients via cognitive dysfunction (n = 1) and hemiparesis (n = 1). CONCLUSIONS: Bypass revascularization of the PCA territory is effective for the treatment of complex vascular lesions affecting the posterior circulation. To address the various surgical segments of the PCA, different approaches are required. Combined approaches allow access to the PCA proximal and distal from the lesion.

Open Surgery for Recurrent Intracranial Aneurysms: Techniques and Long-Term Outcomes.

BACKGROUND: After occlusion of an aneurysm, a patient may experience aneurysm regrowth at the same site or develop de novo aneurysms. We present our experience in microsurgery of recurrent aneurysms with analysis of long-term results. METHODS: The senior authors (R. T. and H. K.) performed recurrent aneurysm clipping on 44 patients at Teishinkai Hospital and Asahikawa Red Cross Hospital in Sapporo, Japan. Operative techniques included clipping only, clipping and protective bypass, trapping of aneurysm with bypass, proximal occlusion, and bypass. Postoperative outcome was analyzed retrospectively using the modified Rankin Scale. RESULTS: Our series included 10 men (23%) and 34 women (77%), with a mean patient age of 63 years (range, 7-82 years). Before primary treatment, 11 patients (25%) had a ruptured aneurysm, while 33 patients (75%) had an unruptured aneurysm. The mean follow-up time after primary surgery was 7.6 years (range, 0.8-25 years). At our department the treatment of recurrent aneurysm included the clipping in 19 patients (43%), clipping with bypass in 6 patients (14%), aneurysm trapping with bypass in 10 patients (23%), and proximal occlusion and bypass in 9 patients (20%). The mean follow-up time after surgical treatment of recurrent aneurysms stood at 3.5 years (range 0.1-9 years). Altogether, 37 patients (84%) experienced favorable outcomes at last follow-up examination (modified Rankin Scale scores 0 and 1). CONCLUSIONS: Microsurgery of recurrent aneurysms may be performed safely and effectively, as shown by our study, in which 84% of patients experienced favorable results.

Is Age a Risk Factor for Poor Outcome of Surgical Treatment of Unruptured Intracranial Aneurysms?

OBJECTIVE: Advanced age is known to be a significant risk factor for the rupture of intracranial aneurysms. The impact of age on outcomes of surgically treated patients with unruptured intracranial aneurysms (UIAs) is less clear. METHODS: A total of 663 consecutive patients with 823 surgically treated UIAs were evaluated. UIAs, which need bypass surgery including low-flow or high-flow bypass, were defined as complex aneurysms. Aneurysm size was categorized as small (<15 mm), large (15-24 mm), and giant (≥25 mm). In patients without symptoms, a poor outcome is defined as a modified Rankin Scale (mRS) score of 2-6. In those with mRS score higher than 1 as a result of UIA-related symptoms or other comorbidities, a poor outcome is defined as an increase of 1 or more on the mRS. Outcomes were evaluated at the 6-month and 12-month follow-up examinations. RESULTS: The mean age was 62 ± 12 years and 650 UIAs (78%) were observed in women. Previously treated aneurysm (P = 0.009), posterior circulation aneurysm (P < 0.0001), complex aneurysm (P < 0.0001), a larger size (P = 0.011), and perforator territory infarction (P < 0.0001) were related to poor outcome at 6 months, and posterior circulation aneurysm (P < 0.0001), complex aneurysm (P < 0.0001), a larger size (P = 0.035), and perforator territory infarction (P = 0.013) were related to poor outcome at 12 months. Age was not associated with poor outcome in patients with UIAs who undertook direct surgery. CONCLUSIONS: Although risks and benefits of aneurysm treatment in older patients should be carefully considered, surgical treatment of UIAs in the elderly should be considered positively.

Risk Factors for Visual Impairments in Patients with Unruptured Intradural Paraclinoid Aneurysms Treated by Neck Clipping without Bypass Surgery.

OBJECTIVE: Although paraclinoid aneurysms are now frequently referred for endovascular treatment, the durability of obliteration is still to be determined. Therefore, direct surgery for paraclinoid aneurysms still remains indispensable. The present study aimed to evaluate the risk factors for the visual impairments in patients with unruptured intradural paraclinoid aneurysms. METHODS: The data of 133 patients with 136 aneurysms treated by neck clipping without bypass surgery was evaluated. Visual impairments included decreased visual acuity and visual field defect. The aneurysm was classified into superior projecting aneurysm, ventral projecting aneurysm, and carotid cave aneurysm. Plug-in method was defined as filling interspace, which was formed between the internal carotid artery and the sutured dura in case of detachment of the dural ring. RESULTS: Postoperative new visual impairments were observed in 30 aneurysms (22%). During the follow-up period (median, 600 days), postoperative new visual impairments continued in 23 aneurysms (17%). Multivariate analysis showed that carotid cave location and plug-in method were related to new visual impairments at 30 days (odds ratio [OR], 2.6; 95% confidence interval [CI] 1.1-6.1; P = 0.031 and OR, 4.1; 95% CI 1.4-12; P = 0.008) and at 6 months (OR, 4.1; 95% CI 1.5-11; P = 0.005 and OR, 3.3; 95% CI 1.1-11; P = 0.045). CONCLUSIONS: The present study showed that carotid cave location and plug-in method during dural closures were related to postoperative continued visual impairments. Neurosurgeons should carefully consider the surgical indication for unruptured carotid cave aneurysms and avoid plug-in methods.

Radical surgical treatment for recurrent giant fusiform thrombosed vertebral artery aneurysm previously coiled.

BACKGROUND: Fusiform aneurysms are rare (<1%) and the underlying pathophysiology is not well known. Endovascular coiling is the standard of treatment; however, a surgical procedure with vascular reconstruction by excluding the pathological segment of the vessel and restoring the blood flow, seems to be the most effective and definitive treatment. CASE DESCRIPTION: We report a patient who presented a fusiform vertebral artery aneurysm previously coiled which developed a giant enlargement and a new contralateral fusiform aneurysm. Hemodynamic changes resulting in the formation of contralateral aneurysm might be the result of aneurysm occlusion without revascularization. In addition, continued blood flow to the aneurysmal wall through the vasa vasorum might result in aneurysm recanalization or regrowth. In order to account for these possible sources of complications, we performed a vascular reconstruction with high and low flow bypasses after trapping the aneurysm. CONCLUSIONS: We hypothesize that, in this and similar cases, surgical vascular reconstruction should be the first and definitive treatment under experienced cerebrovascular surgeons.

Radical treatment for bilateral vertebral artery dissecting aneurysms by reconstruction of the vertebral artery.

OBJECTIVE Bilateral vertebral artery dissecting aneurysms (VADAs) have a poor prognosis because progressive enlargement of the aneurysms compresses the brainstem or causes subarachnoid hemorrhage. The trapping of 1 vertebral artery (VA) places increased hemodynamic stress on the contralateral VA and may lead to enlargement and rupture. Therefore, management strategies are controversial. This study describes a radical treatment for bilateral VADAs using bypass surgery. METHODS Seven patients with bilateral VADAs were included. Three patients were treated by trapping of 1 VA via coiling or clipping at another hospital; the previously treated VA in 1 patient and the contralateral untreated VA in 2 patients subsequently enlarged. The other 4 patients presented without previous intervention and progressive enlargement of the aneurysms. RESULTS The post-coil embolization patients underwent V3-posterior cerebral artery (PCA) bypass and trapping. The other 4 patients underwent VA reconstruction via V3-V4 or V4-V4 bypass, with contralateral trapping on a separate day in 3 patients and observation in 1 patient. Perioperative complications included 1 case of cerebrospinal fluid leakage for which the patient required an additional operation, 1 case of dysphagia and facial palsy due to sigmoid sinus thrombosis, and 1 case of dysphagia. The long-term outcomes of these patients were favorable. CONCLUSIONS Patients with bilateral VADAs require treatment on both sides. If VA trapping is performed first, the treatment options for the other side are limited to V3-PCA bypass and trapping. This procedure is effective; however, it is also invasive and technically difficult. In cases of bilateral VADAs in which it is feasible to reconstruct 1 side, the best approach is to begin by reconstructing the VA that appears technically easiest, followed by trapping of the contralateral VADA. This strategy allows enough time to suture vessels because contralateral reverse flow is maintained.

The Valveless Saphenous Vein Graft Technique for EC-IC High-Flow Bypass: Technical Note.

OBJECTIVE: Extracranial to intracranial (EC-IC) high-flow bypass using radial artery or saphenous vein (SV) graft has remained vital for complex aneurysms. If an Allen test is positive, the radial artery cannot be harvested because of poor palmer collateral circulation. The valves are thought to be one of causes of SV graft failure. Herein we illustrate the "valveless SV graft technique" as bypass conduits. METHODS: Between August 2014 and December 2014 at the Department of Neurosurgery at Teishinkai Hospital, 4 patients whose Allen test was positive underwent EC-IC bypass with the valveless SV graft for complex internal carotid artery (ICA) aneurysm. After SV harvesting, we identified the SV valve, cut it, and performed an end-to-end anastomosis using the fish mouth trimming technique. Graft patency was confirmed by computed tomography angiography. RESULTS: We have not encountered any problems related to graft failure, and all valveless SV grafts were patent during the follow-up period (median, 210 days; interquartile range, 93-287 days). CONCLUSIONS: The valveless SV graft technique is a useful technique in patients with complex ICA aneurysms who undergo EC-IC high-flow bypass with therapeutic ICA occlusion and whose Allen tests are positive.

Retrograde Suction Decompression for Clip Occlusion of Internal Carotid Artery Communicating Segment Aneurysms.

BACKGROUND: Retrograde suction decompression (RSD) can achieve proximal parent vessel control, improve aneurysm neck visualization, and allow parent vessel reconstruction for direct clipping of internal carotid artery (ICA) aneurysms. The aim of the present study was to describe the technique and surgical results of RSD for direct clipping of ICA communicating segment (C1) aneurysms. METHODS: The clinical data and treatment summaries of 20 patients who underwent RSD-assisted clipping of ICA C1 aneurysms were retrospectively reviewed. Pre- and postoperative three- or four-dimensional computed tomography angiograms, postoperative magnetic resonance images, surgical notes, operative complications, and outcomes were assessed. RESULTS: All patients except one harbored unruptured C1 aneurysms. Extracranial-intracranial graft bypass using the radial artery was performed in five patients. Fifteen patients required temporary clipping of the posterior communicating artery for further reduction of blood back-flow into the aneurysm. All aneurysms were successfully clipped and postoperative three- or four-dimensional computed tomography angiography revealed no major branch occlusion or residual aneurysm. At the 6-month follow-up examination, 19 patients had a good outcome and 1 patient had poor outcome associated with anterior choroidal artery ischemia. No death had occurred at 6-month follow-up examination. CONCLUSIONS: The RSD technique is a useful procedure to achieve proximal vascular control, to soften and shrinkage the aneurysm sac, and to provide a wide and clean operative field allowing safe clip placement. The RSD technique requires special attention to the relationship between the perforators and the aneurysm, and close cooperation between the surgeon and the assistant.

Radical resection of a craniopharyngioma via the extradural anterior temporal approach with zygomatic arch osteotomy.

BACKGROUND: Though the extradural anterior temporal approach (EDATA) with zygomatic osteotomy is useful, there are only few reports of this approach being used for craniopharyngioma resection. Herein, we report our surgical case series and the technical importance of EDATA for the radical removal of a craniopharyngioma. METHODS: We report 7 cases of craniopharyngiomas treated surgically between April 1999 and October 2015. The surgical approaches, clinical presentation, pre and postoperative radiographic examination results, surgical outcomes, and morbidity were analyzed. RESULTS: The mean follow-up period was 89.1 months. The surgical approach was EDATA with zygomatic osteotomy in 4, combined interhemispheric translamina terminalis approach (IHTLA) and trans-sylvian anterior temporal approach (ATA) in 2, and IHTLA in 1 patient. Complete tumor resection was achieved in all cases, without any recurrence during the follow-up period. Transient morbidities were oculomotor nerve palsy in 2, and meningitis and hydrocephalus in 1 patient. There was 1 case of permanent morbidity due to hydrocephalus that needed a ventriculoperitoneal shunt, and 1 case of blindness on the operative side. Visual acuity and visual field improved in 4 cases, showed no change in 2 cases, and deteriorated in 1 case. Though the pituitary stalk was preserved in 2 cases, all 7 cases needed total hormone replacement therapy. CONCLUSION: EDATA with zygomatic osteotomy ensures sufficient mobility of the internal carotid artery, and provides a good lateral and look up operative view. Hence, it can be used effectively for radical resection of craniopharyngiomas through the opticocarotid space and retrocarotid space.