Outcomes and complications of cerebral aneurysms operated on by eyebrow incision according to aneurysm type and location.

OBJECTIVE: Trans-eyebrow supraorbital aneurysmal neck clipping, also known as keyhole surgery, have many advantages of minimal invasive surgery. However, there are few studies on whether there is a difference in keyhole surgery according to the location of the aneurysm, and how the complications after keyhole approach differ from the conventional approach. The authors investigated the surgical outcome of keyhole aneurysmal surgery for clarify the characteristics of keyhole surgery. METHODS: A retrospective study was performed with review of medical records and images of patients with anterior circulation aneurysm undergoing aneurysmal clipping with keyhole surgery. The patient's clinical condition, imaging, surgical condition, and outcome were investigated. RESULTS: As a result of analysis about the location of the aneurysm, middle cerebral artery (MCA) aneurysm group had a longer operation time than internal carotid artery and anterior cerebral artery aneurysm groups, but there was no significant difference in complication rate. The olfactory dysfunction occurred more than that of conventional surgery and occurred less in MCA aneurysm group than others. Scalp sensory change in the surgical site was more common in patients with unruptured aneurysms. CONCLUSION: By accurately investigating the frequency and severity of complications associated with trans-eyebrow aneurysmal neck clipping surgery, it can help to select a surgical approach considering risk versus benefit. In addition, patient's satisfaction can be increased by providing information to patients and caregivers in advance about the outcome of this approach and the anticipated complications.

Pneumocephalus and headache following craniotomy during the immediate postoperative period.

BACKGROUND: Pneumocephalus may be responsible for post-craniotomy headache but is easily overlooked in the clinical situation. In the present study, the relationship between the amount of intracranial air and post-craniotomy headache was investigated. METHODS: A retrospective observational study was performed on 79 patients who underwent minimal invasive craniotomy for unruptured cerebral aneurysms. Those who had undergone previous neurosurgery, neurological deficit before and after surgery were excluded The amount of air in the cranial cavity was measured using brain computed tomography (CT) taken within 6 h after surgery. To measure the degree of pain due to intracranial air, daily and total analgesic administration amount were used as a pain index. Correlation between intracranial air volume and total consumption of analgesic during hospitalization was tested using Spearman rank correlation coefficients. Receiver operating characteristics (ROC) analysis was used to determine the amount of air associated with increased analgesic consumption over 72 h postoperatively. RESULTS: The mean amount of intracranial air was 15.6 ± 9.1 mL. Total administration of parenteral and oral analgesics frequency were 6.5 ± 4.5, 13.2 ± 7.9 respectively. A statically significant correlation was observed between daily and total parenteral analgesic consumption after surgery and the amount of intracranial air at followed-up brain CT postoperatively within 24 h (r = 0.69, p < 0.001), within 48 h (r = 0.68, p < 0.001), and total duration after surgery (r = 0.84, p < 0.001). The optimal cut-off value of 12.14 mL of intracranial air predicts the use of parenteral analgesics over 72 h after surgery. CONCLUSIONS: Pneumocephalus may be a causative factor for post-craniotomy pain and headache with surgical injuries.

Intracerebral Hemorrhage due to Thrombosis with Thrombocytopenia Syndrome after Vaccination against COVID-19: the First Fatal Case in Korea.

Vaccination with an adenoviral vector vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can result in the rare development of thrombosis with thrombocytopenia mediated by platelet-activating antibodies against platelet factor 4 (PF4). This is a life-threating condition that may be accompanied by bleeding due to thrombocytopenia with thrombosis of the cerebral venous sinus or splanchnic vein. Herein, we describe the first fatal case of thrombosis with thrombocytopenia syndrome in Korea, presenting with intracranial hemorrhage caused by cerebral venous sinus thrombosis. A 33-year-old Korean man received the first dose of the ChAdOx1 nCoV-19 vaccination. He developed severe headache with vomiting 9 days after the vaccination. Twelve days after vaccination, he was admitted to the hospital with neurological symptoms and was diagnosed with cerebral venous sinus thrombosis, which was accompanied by intracranial hemorrhage. Thrombocytopenia and D-dimer elevation were observed, and the result of the PF4 enzyme-linked immunosorbent assay antibody test was reported to be strongly positive. Despite intensive treatment, including intravenous immunoglobulin injection and endovascular mechanical thrombectomy, the patient died 19 days after vaccination. Physicians need to be aware of thrombosis with thrombocytopenia syndrome (TTS) in adenoviral vector-vaccinated patients. Endovascular mechanical thrombectomy might be a useful therapeutic option for the treatment of TTS with cerebral venous sinus thrombosis.

Oropharyngeal dysphagia in secondary normal pressure hydrocephalus due to corticobulbar tract compression: cases series and review of literature.

The association and mechanism involved in swallowing disturbance and normal pressure hydrocephalus (NPH) needs to be established. We report a case report where a patient who showed progressive swallowing dysfunction was diagnosed with secondary NPH. Tractography analysis showed corticobulbar tract compression by ventricular dilation. Drainage operation led to the recovery of tract volume with an improvement of swallowing function. We also report ten case series in which secondary NPH was associated with a swallowing disturbance. In these cases, dysphagia also showed improvement after shunt operation. We review the literature regarding the corticobulbar tract and its association with swallowing disturbance and the possible underlying pathophysiological mechanism in secondary NPH. This report highlights that swallowing disturbance may manifest in those with secondary NPH due to corticobulbar tract involvement. Our findings suggest that involvement of the corticobulbar tract may be a possible cause of dysphagia in secondary NPH that may be reversible after shunt operation.

Assessing the Adequacy of Superficial Temporal Artery Blood Flow in Korean Patients Undergoing STA-MCA Anastomosis.

OBJECTIVE: Superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis is conducted for flow augmentation. In this study, we measured the STA cut flow of a Korean population and evaluated the relationship between STA cut flow and long-term patency of the bypass. METHODS: A retrospective study was conducted. Intraoperative measurement of STA flow was conducted using a microvascular flow meter on patients who underwent STA-MCA. After cutting the distal end, the STA flow rate was measured with no resistance and recorded. After finishing anastomosis, STA flow was measured and recorded. The cut flow index was calculated by dividing post anastomosis flow by cut flow in intracranial atherosclerotic stenosis patients. RESULTS: The median STA cut flow was 35.0 mL/min and the post anastomosis flow was 24.0 mL/min. The cut flow of STA decreased with aging (p=0.027) and increased with diameter (p=0.004). The cut flow showed no correlation with history of hypertension or diabetes mellitus (p=0.713 and p=0.786), but did correlate a positively with history of hyperlipidemia (p=0.004). There were no statistical differences in cut flow, STA diameter, and post anastomosis flow between the frontal and parietal branches (p=0.081, p=0.853, and p=0.990, respectively). CONCLUSION: The median STA cut flow of a Korean population was 35 mL/min. Upon reviewing previous articles, it appears that there are differences in the STA cut flow between Western and Asian patients.

Analysis of the factors affecting graft infection after cranioplasty.

BACKGROUND: The predictors of graft infection after cranioplasty (GIC) following decompressive craniectomy are not well established. Knowledge of the risk factors for GIC will allow development of preventive measures designed to reduce infection rates. Therefore, the objective of this study was to identify risk factors for the development of GIC. METHODS: A total of 85 patients underwent reconstructive cranioplasty after decompressive craniectomy between January 2009 and July 2011 and had a follow-up period of > 1 year; charts were reviewed retrospectively. Although autograft was used whenever possible, artificial bone was used for cranioplasty. GIC was defined as infection requiring removal of the bone graft. RESULTS: GIC occurred in six patients (7.05 %). GIC was not related to the indications for craniectomy, the interval of cranioplasty, graft material, or the size of the bone defect (p = 0.433, p = 0.206, p = 0.665, and p = 0.999, respectively). The GIC rate was significantly related to previous temporalis muscle resection, preoperative subgaleal fluid collection, operative times > 120 min, and postoperative wound disruptions (p = 0.001, p < 0.001, p = 0.035, and p = 0.016, respectively). Multiple logistic regression showed that the presence of a subgaleal fluid collection before cranioplasty significantly increased the risk of GIC (OR: 38.53; 95 % CI: 2.77-535.6; p = 0.006). CONCLUSIONS: The results of this study suggest that long operative times (> 120 min), craniectomy with temporalis muscle resection, the presence of preoperative subgaleal fluid collection, and postoperative wound disruption may be risk factors for graft infection after cranioplasty. Surgical techniques should be developed to reduce operative time and to avoid temporalis muscle resection when possible. In addition, meticulous dural closure aimed at reducing the formation of subgaleal fluid collection is important for the prevention of graft infections after cranioplasty.

Early Detection of hyperemia with Magnetic Resonance Fluid Attenuation Inversion Recovery Imaging after Superficial Temporal Artery to Middle Cerebral Artery Anastomosis.

Objective: Cerebral hyperperfusion syndrome(CHS) manifests as a collection of symptoms brought on by heightened focal cerebral blood flow, afflicting nearly 30% of patients who have undergone superficial temporal artery(STA)-middle cerebral artery(MCA) anastomosis. The aim of this study was to investigate whether the amalgamation of magnetic resonance imaging(MRI) fluid-attenuated inversion recovery(FLAIR) and apparent diffusion coefficient(ADC) imaging via MRI can discern cerebral hyperemia after STA-MCA anastomosis surgery. Methods: A retrospective study was performed of patients who underwent STA-MCA anastomosis due to Moyamoya disease or atherosclerotic steno-occlusive disease. A protocol aimed at preventing CHS was instituted, leveraging the use of MRI FLAIR. Patients underwent MRI diffusion with FLAIR imaging 24 h after STA-MCA anastomosis. A high signal on FLAIR images signified the presence of hyperemia at the bypass site, triggering a protocol of hyperemia care. All patients underwent hemodynamic evaluations, including perfusion MRI, single-photon emission computed tomography(SPECT), and digital subtraction angiography, both before and after the surgery. If a high signal intensity is observed on MRI FLAIR within 24 hours of the surgery, a repeat MRI is performed to confirm the presence of hyperemia. Patients with confirmed hyperemia are managed according to a protocol aimed at preventing further progression. Results: Out of a total of 162 patients, 24 individuals(comprising 16 women and 8 men) exhibited hyperemia on their MRI FLAIR scans following the procedure. SPECT was conducted on 23 patients, and 11 of them yielded positive results. All 24 patients underwent perfusion MRI, but 9 of them showed no significant findings. Among the patients, 10 displayed elevations in both cerebral blood flow(CBF) and cerebral blood volume(CBV), 3 only showed elevation in CBF, and 2 only showed elevation in CBV. Follow-up MRI FLAIR scans conducted 6 months later on these patients revealed complete normalization of the previously observed high signal intensity, with no evidence of ischemic injury. Conclusion: The study determined that the use of MRI FLAIR and ADC mapping is a competent means of early detection of hyperemia after STA-MCA anastomosis surgery. The protocol established can be adopted by other neurosurgical institutions to enhance patient outcomes and mitigate the hazard of permanent cerebral injury caused by cerebral hyperemia.

Anatomical predictors of difficult left internal carotid artery navigation in transradial access for neurointervention.

OBJECTIVE: Transradial access (TRA) has received considerable attention in the field of neurointervention owing to its advantages over transfemoral access. However, the difficulty of left internal carotid artery (ICA) navigation under certain anatomical conditions of the aortic arch and its branches is a limitation of right TRA. In this study the authors aimed to investigate the anatomical predictors that impede navigation of the left ICA in right TRA. METHODS: From January to October 2020, 640 patients underwent transradial angiography at a single institute. Among them, 263 consecutive patients who were evaluated by contrast-enhanced MRA before transradial angiography were included in the study and assigned to success or failure groups according to whether left ICA navigation was possible or not. Several anatomical predictors were investigated to evaluate the correlation of the success of left ICA navigation in right TRA. RESULTS: A higher grade of the aortic arch type (type I vs type III: OR 6.323, p = 0.0171), higher height of the right subclavian artery (OR 1.071, p = 0.0068), narrower turnoff angle of the left common carotid artery (CCA) (OR 0.953, p = 0.0017), wider distance between the innominate artery and the left CCA (OR 1.784, p < 0.0001), steeper angulation of the right subclavian artery (tortuous vs kinking: OR 6.323, p = 0.0066), and steeper angulation of the left CCA (normal vs tortuous: OR 7.453, p = 0.0087; normal vs kinking: OR 51.65, p < 0.0001) were significantly associated with successful navigation of the left ICA. The cutoff value of the height of the right subclavian artery, distance between the innominate artery and the left CCA, turnoff angle of the left CCA, and diameter of the left CCA were 54.83 mm, 4.25 mm, 17°, and 6.05 mm, respectively. CONCLUSIONS: Successful left ICA navigation in right TRA was related to the specific vascular geometry of the aortic arch and its branches. Preprocedural evaluation of the anatomical predictors identified in this study may enhance the success rate of left ICA navigation in right TRA.

Association of Bypass Surgery and Mortality in Moyamoya Disease.

Background Patients with moyamoya disease (MMD) have a high risk of stroke or death. We investigated whether extracranial to intracranial bypass surgery can reduce mortality by preventing strokes in patients with MMD. Methods and Results This nationwide retrospective cohort study encompassed patients with MMD registered under the Rare Intractable Diseases program via the Relieved Co-Payment Policy between 2006 and 2019, using the Korean National Health Insurance Service database. Following a 4-year washout period, landmark analyses were employed to assess mortality and stroke occurrence between the bypass surgery group and the nonsurgical control group at specific time points postindex date (1 month and 3, 6, 12, and 36 months). The study included 18 480 patients with MMD (mean age, 40.7 years; male to female ratio, 1:1.86) with a median follow-up of 5.6 years (interquartile range, 2.5-9.3; mean, 6.1 years [SD, 4.0 years]). During 111 775 person-years of follow-up, 265 patients in the bypass surgery group and 1144 patients in the nonsurgical control group died (incidence mortality rate of 618.1 events versus 1660.3 events, respectively, per 105 person-years). The overall adjusted hazard ratio (HR) revealed significantly lower all-cause mortality in the bypass surgery group from the 36-month landmark time point, for any stroke mortality from 3- and 6-month landmark time points, and for hemorrhagic stroke mortality from the 6-month landmark time point. Furthermore, the overall adjusted HRs for hemorrhagic stroke occurrence were beneficially maintained from all 5 landmark time points in the bypass surgery group. Conclusions Bypass surgery in patients with MMD was associated with a lower risk of all-cause and hemorrhagic stroke mortality and hemorrhagic stroke occurrence compared with nonsurgical control.

Early Restoration of Hypoperfusion Confirmed by Perfusion Magnetic Resonance Image after Emergency Superficial Temporal Artery to Middle Cerebral Artery Anastomosis.

OBJECTIVE: Emergency superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis in patients with large vessel occlusion who fails mechanical thrombectomy or does not become an indication due to over the time window can be done as an alternative for blood flow restoration. The authors planned this study to quantitatively measure the degree of improvement in cerebral perfusion flow using perfusion magnetic resonance imaging (MRI) after bypass surgery and to find out what factors are related to the outcome of the bypass surgery. METHODS: For a total of 107 patients who underwent emergent STA-MCA bypass surgery with large vessel occlusion, the National Institute of Health stroke scale (NIHSS), modified Rankin score (mRS), infarction volume, and hypoperfusion area volume was calculated, the duration between symptom onset and reperfusion time, occlusion site and infarction type were analyzed. After emergency STA-MCA bypass, hypoperfusion area volume at post-operative 7 days was calculated and analyzed compared with pre-operative hypoperfusion area volume. The factors affecting the improvement of mRS were analyzed. The clinical status of patients who underwent emergency bypass was investigated by mRS and NIHSS before and after surgery, and changes in infarct volume, extent, degree of collateral circulation, and hypoperfusion area volume were measured using MRI and digital subtraction angiography (DSA). RESULTS: The preoperative infarction volume was median 10 mL and the hypoperfusion area volume was median 101 mL. NIHSS was a median of 8 points, and the last normal to operation time was a median of 60.7 hours. STA patency was fair in 97.1% of patients at 6 months follow-up DSA and recanalization of the occluded vessel was confirmed at 26.5% of patients. Infarction volume significantly influenced the improvement of mRS (p=0.010) but preoperative hypoperfusion volume was not significantly influenced (p=0.192), and the infarction type showed marginal significance (p=0.0508). Preoperative NIHSS, initial mRS, occlusion vessel type, and last normal to operation time did not influence the improvement of mRS (p=0.272, 0.941, 0.354, and 0.391). CONCLUSION: In a patient who had an acute cerebral infarction due to large vessel occlusion with large ischemic penumbra but was unable to perform mechanical thrombectomy, STA-MCA bypass could be performed. By using time-to-peak images of perfusion MRI, it is possible to quickly and easily confirm that the brain tissue at risk is preserved and that the ischemic penumbra is recovered to a normal blood flow state.

Extracranial Carotid-Vertebral Artery Bypass Technique and Surgical Outcomes.

Vertebral artery (VA) occlusion is frequently encountered, usually without acute ischemic injury of the brain. However, when it is accompanied by hypoplasia or stenosis of the opposite VA, brain ischemia may develop due to insufficient collateral supply. Both hemodynamic instability and embolic infarction can occur in VA occlusion, which may cause severe symptoms in a patient. Extracranial carotid-VA bypass should be considered for symptomatic VA occlusion patients, especially when the patient has repeated ischemic brain injuries. In this report, the cases of three extracranial carotid-VA bypass patients are introduced, along with a brief description of the surgical techniques. All three cases were treated with different bypass methods according to their disease location.

Diplopia as a presenting symptom in a gastric gastrointestinal stromal tumor.

Gastrointestinal stromal tumors are the most common mesenchymal neoplasm of the gastrointestinal tract. Distant metastasis of gastrotintestinal stromal tumors occurs in ∼50% of the cases and is usually found in the liver and peritoneum. We present a patient with diplopia which was due to a metastatic gastrointestinal stromal tumor of the clivus. Transsphenoidal resection of the tumor was performed and post-operative treatment with oral imatinib mesylate was done. One month after the surgery, treatment was started with imatinib and the patient's diplopia improved within 15 days. Follow-up computed tomography was taken 2 months after the initiation of oral imatinib, and the size of the main gastric mass has decreased. To our knowledge, this is an extremely rare case of gastrointestinal stromal tumor with metastasis to the clivus with diplopia as the presenting symptom. We report our clinical findings along with a review of the relevant literature.

Angiographic and clinical outcomes of stent-alone treatment for spontaneous vertebrobasilar dissecting aneurysm.

PURPOSE: Spontaneous vertebrobasilar dissecting aneurysm (VBD) is a very challenging disease with an unpredictable clinical course and controversies on treatment strategy. The present study reports radiological and clinical outcomes of stent-alone treatment (SAT) for VBD. METHODS: Twenty-four VBDs treated with SAT are included in the present study. Clinical and angiographic data were reviewed retrospectively. RESULTS: A total of 24 lesions in 22 patients with a mean follow-up period of 16.21 months were included. Of the 24 individual lesions, 23 were intracranial vertebral artery lesions and 1 lesion was located in the basilar artery. There were six cases of ruptured dissections with the other cases having various symptoms. The immediate post-SAT angiographic outcomes included 5 lesions with good remodeling over 90% recovery and 19 poorly remodeled lesions. The latest angiographic outcomes included 17 cases of good remodeling (remodeling rate over 90%), 6 cases of poor remodeling (remodeling rate below 70%), and 1 case with morphological aggravation. The overlapping stent technique was used in seven cases and it was significantly associated with good angiographic results. None of the rupture cases underwent re-rupture post SAT. There was one case of a symptomatic complication of a femoral arteriovenous fistula. CONCLUSIONS: The SAT could be a feasible alternative for the treatment of VBD. The overlapping technique was significantly associated with good angiographic outcome. We expect that technological development of the intracranial stent will allow better procedural outcomes of SAT.

Transarterial coil embolization of a carotid-cavernous fistula which occurred during stent angioplasty.

Intracranial endovascular procedures are less invasive and relatively safe; however, these procedures do carry a risk of complications, such as thromboembolization, arterial injury, and vessel occlusion. We present a case of carotid-cavernous fistula development secondary to injury of the cavernous segment of the internal carotid artery (ICA) during stent angioplasty and its treatment by transarterial coil embolization. Probable causes of this complication and its treatment method are discussed. To the best of our knowledge, this is the first report of such a case.

Subarachnoid hemorrhage model in the rat: modification of the endovascular filament model.

The present study describes modifications to the endovascular filament model of subarachnoid hemorrhage (SAH) in rats. Specifically, we sought to improve the percentage yield of SAH, reduce mortality rates and better simulate human cerebral aneurysmal rupture. Instead of using a 4-0 prolene suture to induce SAH in the existing endovascular filament model, a hollow and flexible polyetrafluoroethylene (PTFE) tube was maneuvered into the proximal anterior cerebral artery (ACA) to ensure that advancement occurred without producing trauma to the vessels. SAH was induced by advancing a tungsten wire through this tube, perforating the ACA at the desired location. These modifications produced significant improvements over the endovascular filament model. Mortality rate declined from 46 to 19%, and SAH was produced more frequently. With the prolene suture, only 48% of our attempts produced a SAH, and unsuccessful attempts typically resulted in an acute subdural hematoma (ASDH). In contrast, the wire/tubing technique was 90% successful at inducing SAH, and led to a significant reduction of ASDH incidence from 44 to 6%. Additionally, the modified technique produced vasospasm in basilar and middle cerebral arteries post-SAH as well as pseudoaneurysms in the proximal ACA which indicated the location of vessel perforation.

Intravascular ultrasonography-guided stent angioplasty of an extracranial vertebral artery dissection.

The authors report on a case of intravascular ultrasonography (IVUS)-guided stent angioplasty for iatrogenic extracranial vertebral artery (VA) dissection in a 49-year-old man after coil embolization for an unruptured aneurysm of the right posterior inferior cerebellar artery. Insignificant dissections occurred during the procedure. Postoperatively, the patient experienced gradually worsening posterior neck pain and headache, and follow-up angiography 8 months after the coil embolization revealed expansion of the dissection. The patient underwent stent angioplasty with IVUS guidance and his symptoms improved. To the authors' knowledge, this is the first report of IVUS-guided stent angioplasty of an extracranial VA dissection. It was safe and feasible to treat extracranial VA dissections with stent placement under IVUS guidance. Intravascular environments are in real time with IVUS, and this technique is useful in the confirmation of a true lumen and evaluation of appropriate stent apposition. More clinical experience with this technique is necessary and mandatory, and devices with smaller diameters with improved trackability are essential for further introduction of IVUS into the field of endovascular neurosurgery.

Large Scalp Defect Repair with Flap Reconstruction Using Tissue Expander After Combined Bypass in Case of Moyamoya Disease.

BACKGROUND: Combined revascularization is the preferred surgical management of adult Moyamoya disease. However, postoperative flap necrosis of the scalp is not an uncommon complication. We investigated the role of scalp incision design on the basis of the course of the superficial temporal artery (STA) to prevent postoperative scalp necrosis. The utility of tissue expander in wide scalp defect repair is explored. CASE DESCRIPTION: A 13-year-old female patient underwent STA-to-middle cerebral artery anastomosis and encephaloduroarteriosynangiosis due to ischemic symptoms. However, she suffered from wide scalp necrosis measuring 10.5 × 10 cm after bypass surgery. Conventional rotational scalp flap reconstruction was impossible due to the wide defect, and therefore split thickness skin graft was considered. However, aesthetic compromise or hair loss is a psychologic burden in an adolescent female. Two tissue expanders were inserted under the contralateral normal scalp, and a gradual expansion was achieved by saline infusion for 3 months. Finally, a wide scalp flap, which covered the large defect, was obtained using this procedure. The patient underwent rotational flap advancement and was discharged without any hair loss wound. CONCLUSIONS: Miserable scalp flap design results in a large scalp defect during combined bypass surgery. However, tissue expanders aided the reconstruction of a large scalp defect. Reconstruction using tissue expanders and advancement of local rotation flap is recommended in case of large scalp necrosis. The procedure yields cosmetically superior outcomes due to scalp hair conservation and concealment of postoperative scar behind the hair line.

Usefulness and Stability of Intraoperative Digital Subtraction Angiography Using the Transradial Route in Arteriovenous Malformation Surgery.

BACKGROUND: Digital subtraction angiography is the gold standard to confirm complete removal of an arteriovenous malformation (AVM) nidus. However, the transfemoral approach requires specialized instrumentation and is cumbersome and difficult to perform with the patient in the prone or decubitus position. We report the use of intraoperative digital subtraction angiography (iDSA) with the transradial approach and examine its usefulness and safety. MATERIALS AND METHODS: We retrospectively reviewed clinical features, radiologic images, surgical findings, and iDSA findings of patients with AVM who underwent surgery for nidus removal. Transradial iDSA was performed within 30 minutes for patients who required angiographic confirmation after AVM resection. This procedure was simple with the radial arterial line for blood pressure monitoring used as digital subtraction angiography catheter access route. RESULTS: Transradial iDSA was performed in 23 patients. Twelve patients were not in the general supine position during neurosurgery; 7 patients were operated on in prone position, and 5 patients were operated on in the park bench position. Remnant nidus was identified by iDSA in 2 patients, and additional measures were required. CONCLUSIONS: Intraoperative cerebral angiography during surgery for cerebral AVM could be performed safely via the transradial approach. This approach showed several merits in terms of easy access; no extra requirements, such as preoperative sheath implantation, anticoagulation during the surgery, or a radiolucent table; and usefulness in any surgical position. Further studies using this approach and comparison with the transfemoral approach are necessary.

Risk Factor Analysis for Poor Outcomes in Supraorbital Keyhole Aneurysm Clipping for Ruptured Anterior Circulation Aneurysms.

BACKGROUND: The transciliary keyhole approach has been actively employed for unruptured intracranial aneurysms in many institutions, although applying this technique to ruptured aneurysms remains controversial. We investigated risk factors related to poor surgical outcomes in ruptured aneurysms and attempted to clarify the differences between conventional craniotomy and keyhole surgery. METHODS: A retrospective review was performed at a single institution of medical records and images from surgeries of 188 patients who underwent keyhole surgery for ruptured anterior circulation aneurysms between July 2007 and February 2015. RESULTS: The study included 116 (62%) female and 72 (38%) male patients; age range was 23-86 years. Preoperative clinical grades were good in almost all patients except for a few patients with poor clinical grades. Mean aneurysm size was 5.5 mm, and the most common aneurysm location was the anterior communicating artery (n = 82). Most patients (n = 158; 91.5%) showed good clinical outcomes. Univariate analysis of risk factors associated with poor-grade outcomes after 3 months was performed. Hunt and Hess grade (odds ratio [OR] 13.50, P < 0.0001), World Federation of Neurosurgical Societies scale (OR 7.69, P < 0.0001), aneurysm size (OR 1.21, P = 0.019), and vasospasm (OR 6.43, P = 0.0003) were statistically significant, whereas Fisher grade, skin-to-skin time (operation time), rebleeding, and ventricle puncture were not statistically significant. CONCLUSIONS: Because incidence of poor surgical outcome of keyhole surgery is not different from known conventional craniotomy, this approach is an acceptable treatment option in a good-grade ruptured anterior circulation aneurysm.