Epidemiology of post-suboccipital craniotomy headache: A multicentre retrospective study.

The detailed epidemiology and mechanism of post-craniotomy headaches are not well understood. This study aimed to establish the actual clinical incidence and causes of post-craniotomy headaches. Suboccipital craniotomy surgeries performed in six institutions within the five-year study period were included. This study included 311 patients (138 males, 173 female; mean age, 59.3 years old). A total of 145 patients (49%) experienced post-craniotomy headaches. Microvascular decompression surgery, craniectomy and facial spasms were significant risk factors for post-craniotomy headaches. In most cases, the post-craniotomy headaches disappeared within one month; however, some patients suffered from long-term headaches. The craniotomy site and the methods of dura and skull closures should be individually determined for each patient. However, to prevent post-craniotomy headaches, craniotomy, instead of craniectomy, may be considered.

Direct Carotid-Cavernous Fistula Caused by Internal Carotid Artery Perforation by a Microcatheter Body during Mechanical Thrombectomy.

Rapid advances in emergent mechanical thrombectomy have resulted in a higher occurrence of arterial perforations during neurointerventions. Here, we report a case of internal carotid artery (ICA) perforation during mechanical thrombectomy in a 78-year-old man with a left middle cerebral artery occlusion. The ICA was perforated by a microcatheter during thrombectomy, forming a direct carotid-cavernous fistula. A two-stage drainer occlusion was conducted because of cortical venous reflex aggravation and ocular symptoms. Here, we report the perforation details and treatment, adding to evidence that ICA perforation with the microcatheter body is a concern during mechanical thrombectomy.

Sex Difference and Rupture Rate of Intracranial Aneurysms: An Individual Patient Data Meta-Analysis.

BACKGROUND AND PURPOSE: In previous studies, women had a higher risk of rupture of intracranial aneurysms than men, but female sex was not an independent risk factor. This may be explained by a higher prevalence of patient- or aneurysm-related risk factors for rupture in women than in men or by insufficient power of previous studies. We assessed sex differences in rupture rate taking into account other patient- and aneurysm-related risk factors for aneurysmal rupture. METHODS: We searched Embase and Pubmed for articles published until December 1, 2020. Cohorts with available individual patient data were included in our meta-analysis. We compared rupture rates of women versus men using a Cox proportional hazard regression model adjusted for the PHASES score (Population, Hypertension, Age, Size of Aneurysm, Earlier Subarachnoid Hemorrhage From Another Aneurysm, Site of Aneurysm), smoking, and a positive family history of aneurysmal subarachnoid hemorrhage. RESULTS: We pooled individual patient data from 9 cohorts totaling 9940 patients (6555 women, 66%) with 12 193 unruptured intracranial aneurysms, and 24 357 person-years follow-up. Rupture occurred in 163 women (rupture rate 1.04%/person-years [95% CI, 0.89-1.21]) and 63 men (rupture rate 0.74%/person-years [95% CI, 0.58-0.94]). Women were older (61.9 versus 59.5 years), were less often smokers (20% versus 44%), more often had internal carotid artery aneurysms (24% versus 17%), and larger sized aneurysms (≥7 mm, 24% versus 23%) than men. The unadjusted women-to-men hazard ratio was 1.43 (95% CI, 1.07-1.93) and the adjusted women/men ratio was 1.39 (95% CI, 1.02-1.90). CONCLUSIONS: Women have a higher risk of aneurysmal rupture than men and this sex difference is not explained by differences in patient- and aneurysm-related risk factors for aneurysmal rupture. Future studies should focus on the factors explaining the higher risk of aneurysmal rupture in women.

Difference in Rupture Risk Between Familial and Sporadic Intracranial Aneurysms: An Individual Patient Data Meta-analysis.

BACKGROUND AND OBJECTIVES: We combined individual patient data (IPD) from prospective cohorts of patients with unruptured intracranial aneurysms (UIAs) to assess to what extent patients with familial UIA have a higher rupture risk than those with sporadic UIA. METHODS: For this IPD meta-analysis, we performed an Embase and PubMed search for studies published up to December 1, 2020. We included studies that (1) had a prospective study design; (2) included 50 or more patients with UIA; (3) studied the natural course of UIA and risk factors for aneurysm rupture including family history for aneurysmal subarachnoid haemorrhage and UIA; and (4) had aneurysm rupture as an outcome. Cohorts with available IPD were included. All studies included patients with newly diagnosed UIA visiting one of the study centers. The primary outcome was aneurysmal rupture. Patients with polycystic kidney disease and moyamoya disease were excluded. We compared rupture rates of familial vs sporadic UIA using a Cox proportional hazard regression model adjusted for PHASES score and smoking. We performed 2 analyses: (1) only studies defining first-degree relatives as parents, children, and siblings and (2) all studies, including those in which first-degree relatives are defined as only parents and children, but not siblings. RESULTS: We pooled IPD from 8 cohorts with a low and moderate risk of bias. First-degree relatives were defined as parents, siblings, and children in 6 cohorts (29% Dutch, 55% Finnish, 15% Japanese), totaling 2,297 patients (17% familial, 399 patients) with 3,089 UIAs and 7,301 person-years follow-up. Rupture occurred in 10 familial cases (rupture rate: 0.89%/person-year; 95% confidence interval [CI] 0.45-1.59) and 41 sporadic cases (0.66%/person-year; 95% CI 0.48-0.89); adjusted hazard ratio (HR) for familial cases 2.56 (95% CI 1.18-5.56). After adding the 2 cohorts excluding siblings as first-degree relatives, resulting in 9,511 patients, the adjusted HR was 1.44 (95% CI 0.86-2.40). DISCUSSION: The risk of rupture of UIA is 2.5 times higher, with a range from a 1.2 to 5 times higher risk, in familial than in sporadic UIA. When assessing the risk of rupture in UIA, family history should be taken into account.

Identifying Cerebral Large Vessel Occlusion in Acute Ischemic Stroke by MRI Positioning Scanning.

Various approaches have been tried for acute ischemic stroke (AIS) treatment to shorten the time from onset to recanalization. MRI positioning scanning (PS), which must be taken before any MRI sequences, was examined whether it can detect cerebral large vessel occlusion. A total of 68 consecutive patients with AIS who underwent MRI and were treated with intravenous recombinant tissue plasminogen activator or mechanical thrombectomy at our hospital were retrospectively included in this study. Occluded vessels were identified on the axial or coronal views of PS images, and these images were compared with 3D time-of-flight MRA and digital subtraction angiogram. The sensitivities, positive predictive values (PPVs), and negative predictive values (NPVs) for internal carotid artery (ICA), the proximal M1, distal M1, and M2 segment of the middle cerebral artery occlusion were assessed, and the number of PS slices was assessed. The sensitivities of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 62%, 21%, 35%, and 86%, respectively. The PPVs of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 81%, 88%, 100%, and 97%, respectively, and the NPVs of the axial slices for ICA, proximal M1, distal M1, and M2 occlusion were 94%, 90%, 86%, and 100%, respectively. The detection rate for the ICA was significantly higher with three axial slices (91%) than with two slices (47%) (p <0.01). MRI PS is warranted to be referred to detect large cerebral vessel occlusion.

Endovascular Stent Grafting for Recurrent Strokes Due to Fragile Innominate Artery Plaque: A Case Report.

Here we describe a case of recurrent ischemic strokes due to fragile innominate artery plaque successfully treated using endovascular stent grafting. An 80-year-old man presented with a history of recurrent strokes that were refractory to medical treatment. Computed tomography and magnetic resonance images of the thorax revealed a gross intramural plaque in the innominate artery. He was successfully treated using endovascular stent grafting. An AFX stent graft device was used to prevent further embolic strokes. The AFX stent graft has a unique endoskeleton design with a thin-walled expanded polytetrafluoroethylene fabric-known as active sealing structure-attached to the implant. Postoperatively, the patient has experienced no recurrent strokes in over 2 years of follow-up. The stent grafting procedure could be an optimal treatment option for treating fragile innominate artery plaques.

Arteriovenous fistula of the clival diploic vein associated with arteriovenous fistula of the posterior condylar canal.

We herein report a rare case of a patient with a clival diploic vein arteriovenous fistula (AVF) associated with a posterior condylar canal AVF and discuss the radiological features of clival diploic vein AVF during decision-making on treatment strategies. A 69-year-old male patient with one-year history of pulsatile tinnitus was evaluated with magnetic resonance angiography, which revealed a dilated venous structure. Digital subtraction angiography revealed AVFs located in the clivus and posterior condylar canal. The clival diploic vein AVF was fed by the right internal maxillary artery and the petrous branch of middle meningeal artery and shed to the posterior condylar canal only through an intraosseous vein in the jugular tubercle. Although a catheter could not be navigated into the venous pouch in the clivus, the AVFs were successfully obliterated by transvenous embolization of the venous pouch in the posterior condylar canal.

Mechanical thrombectomy for occlusion near a ruptured intracranial aneurysm: A case report.

BACKGROUND: While recent randomized clinical trials have shown the efficacy of mechanical thrombectomy for acute large vessel anterior cerebral occlusion, cases in patients with a subarachnoid hemorrhage (SAH) were excluded from the study. CASE DESCRIPTION: A 58-year-old man presented with a SAH as a result of a ruptured middle cerebral artery aneurysm. Coil embolization was performed, and a right intracranial angiography showed remnants of an aneurysmal neck. However, the following angiography also revealed a thromboembolic complication that occurred in the same territory as the ruptured aneurysm. The patient underwent a rescue mechanical thrombectomy under the working projection. We deployed a retrieval stent without covering the aneurysmal neck. The occluded vessel was recanalized without any hemorrhagic complication. Due to minimal intracerebral infarction, the patient had good outcomes. CONCLUSION: Mechanical thrombectomy is a useful option to retrieve a clot from an occluded intracranial vessel located near a ruptured aneurysm. Approaching the clot at the working projection is important to ensure safety in the setting of a ruptured aneurysm.

Treatment Outcomes of Burr-Hole Surgery for Chronic Subdural Hematoma in the Elderly Living Beyond Life Expectancy: A Study Comparing Cure, Recurrence, and Complications in Patients Aged ≥80 Years versus ≤79 Years.

BACKGROUND: Few reports have focused on chronic subdural hematoma (CSDH) in the very elderly, who have lived beyond average life expectancy. Our aim is to appraise treatment outcomes of burr-hole craniotomy for CSDH in the elderly, focusing on cure, recurrence, and complications. METHODS: Fifty patients ≤79 years of age (group A) and 73 patients ≥80 years of age (group B) were studied. Recurrence was defined as requiring reoperation for hematoma regrowth or symptomatic failure. A cure was regarded as having been achieved in the absence of hematoma on postoperative computed tomography. Complications were defined as any harmful event related to the treatment procedure for CSDH. RESULTS: Cure was documented in 31 patients in group A (63%) and 24 patients in group B (33%) (P = 0.0017). Median intervals to cure were 2.76 and 3.73 months, respectively (P = 0.06). Cumulative cure rates were 51%/76% and 36%/59%, respectively, at the sixth/twelfth postoperative months. Recurrence was documented in 2 patients (4%) and 11 patients (15%), respectively (P = 0.07). Median intervals to recurrence were 0.81 and 1.25 months, respectively (P = 0.049). Cumulative recurrence-free rates were 96%/92% and 87%/75%, respectively, at the third/sixth postoperative months. Complications were observed in 2 patients (4%) and 4 patients (5%), respectively (P = 1.00). CONCLUSIONS: With advancing age, CSDH might show a greater tendency to recur and a longer time is required to achieve a cure. However, complications developed only in high-risk patients. Thus, surgical treatment for CSDH in elderly patients, even those who have lived beyond life expectancy, might provide acceptably effective results.

Endovascular treatments for posterior cerebral artery aneurysms and vascular insufficiency of fetal-type circulation after parent artery occlusion.

We present a retrospective analysis of endovascular treatments for posterior cerebral artery (PCA) aneurysms and discuss the susceptibility of a fetal-type PCA to vascular insufficiency after parent artery occlusion. Among 1207 aneurysms treated with endovascular therapy between March 1997 and March 2013 in our institution, 10 patients (0.8%) presented PCA aneurysms. The principal strategy was to employ selective coil embolization for the aneurysm. However, in certain cases of fusiform or dissecting aneurysms, we performed parent artery occlusion with coils. Clinical and radiological data were collected from hospital charts and evaluated retrospectively. The mean age was 52.7±15.6years (range, 12-65years). Five patients (50%) were admitted with a subarachnoid hemorrhage, and one patient presented with slowly developing paralysis. The remaining four patients were diagnosed incidentally. Five patients underwent selective coil embolization, and five patients underwent parent artery occlusion. All endovascular therapies were successfully performed. However, two patients in the parent artery occlusion group suffered cerebral infarction, and both patients exhibited a fetal-type PCA. The remaining three patients in the parent artery occlusion group exhibited an adult-type PCA and did not suffer a cerebral infarction. Endovascular treatment with either selective coil embolization or parent artery occlusion is safe and effective as the long as the anatomical type of the PCA is considered. Patients with a fetal-type PCA may develop vascular insufficiency upon parent artery occlusion. Neurosurgeons should attempt to preserve the parent artery using a flow-diverting stent or stent-assisted technique for a fetal-type PCA aneurysm.

Carotid Artery Stenting in Right-sided Aortic Arch: A Case Report.

The present report describes a patient with pseudo-occlusion of the left internal carotid artery accompanied by aortic anomalies consisting of right-sided aortic arch with aberrant left subclavian artery arising from Kommerell's diverticulum. Initial attempt of carotid artery stenting via the trans-femoral approach was unsuccessful because of low origin of the left common carotid artery. Therefore, carotid artery stenting (CAS) via the trans-brachial approach was successfully performed with distal balloon protection. Eight months later, the patient presented with restenosis of the left internal carotid artery, and CAS via the trans-brachial approach was performed again. CAS via the trans-brachial approach should be considered when standard femoral access is relatively contraindicated due to aortic anomalies consisting of a right-sided aortic arch.

Abducent nerve palsy treated by microvascular decompression: a case report and review of the literature.

Too few cases of isolated abducent nerve palsy caused by neurovascular compression syndrome have been reported. We here report on a case of abducent nerve palsy caused by neurovascular compression syndrome that was successfully treated by microvascular decompression (MVD). A 46-year-old male presented with a 6-month history of right-sided persistent abducent nerve palsy. High-resolution magnetic resonance imaging revealed a neurovascular contact of the vertebral artery with the right abducent nerve. MVD was performed via a retrosigmoid craniotomy, with remarkable improvement of the palsy. Our report suggests that MVD might be considered as an optional treatment if the symptoms progress or persist.

Endovascular embolization of brain arteriovenous malformations with Eudragit-E.

Eudragit-E was originally developed as a non-adhesive liquid embolic material in the late 1990s and is a copolymer of methyl and butyl methacrylate and dimethylaminoethyl methacrylate that is dissolved in ethanol and iopamidol. This material has been used for endovascular embolization of brain arteriovenous malformations (AVMs) for some time but is currently not widely used. Because safety and feasibility of Eudragit-E has not been well documented, we here report our experience using this material for treating 22 human brain AVMs. From June 1998 to February 2014, 30 endovascular procedures using Eudragit-E were performed to treat 22 patients, including 14 men and 8 women with a mean age of 41.1 years (15-70 years). The mean follow-up period was 56 months (12-129 months), and the Spetzler-Martin grades were I (4 patients), II (9 patients), III (5 patients), and IV (4 patients). Residual AVMs were treated with stereotactic radiosurgery or surgery. The rate of complete obliteration with embolization alone was 27.3%. The overall obliteration rate after endovascular embolization with/without subsequent stereotactic radiosurgery or surgery was 72.7%. Eudragit-E caused two cases of cerebral infarction. One case of intracerebral hemorrhage due to postoperative hemodynamic changes also occurred. The rate of complications directly related to embolization was 10.0%. The safety and effectiveness of Eudragit-E embolization were satisfactory.

Prediction model for 3-year rupture risk of unruptured cerebral aneurysms in Japanese patients.

OBJECTIVE: To build a prediction model that estimates the 3-year rupture risk of unruptured saccular cerebral aneurysms. METHODS: Survival analysis was done using each aneurysm as the unit for analysis. Derivation data were from the Unruptured Cerebral Aneurysm Study (UCAS) in Japan. It consists of patients with unruptured cerebral aneurysms enrolled between 2000 and 2004 at neurosurgical departments at tertiary care hospitals in Japan. The model was presented as a scoring system, and aneurysms were classified into 4 risk grades by predicted 3-year rupture risk: I, < 1%; II, 1 to 3%; III, 3 to 9%, and IV, >9%. The discrimination property and calibration plot of the model were evaluated with external validation data. They were a combination of 3 Japanese cohort studies: UCAS II, the Small Unruptured Intracranial Aneurysm Verification study, and the study at Jikei University School of Medicine. RESULTS: The derivation data include 6,606 unruptured cerebral aneurysms in 5,651 patients. During the 11,482 aneurysm-year follow-up period, 107 ruptures were observed. The predictors chosen for the scoring system were patient age, sex, and hypertension, along with aneurysm size, location, and the presence of a daughter sac. The 3-year risk of rupture ranged from <1% to >15% depending on the individual characteristics of patients and aneurysms. External validation indicated good discrimination and calibration properties. INTERPRETATION: A simple scoring system that only needs easily available patient and aneurysmal information was constructed. This can be used in clinical decision making regarding management of unruptured cerebral aneurysms.

Carotid artery stenting without post-stenting balloon dilatation.

PURPOSE: To evaluate the clinical outcome and MRI findings after carotid artery stenting (CAS) without post-dilatation. METHODS: Between May 2005 and April 2012, a total of 169 consecutive patients (61.4% symptomatic) underwent 176 CAS procedures performed with an embolic protection device (GuardWire, n=116; FilterWire EZ, n=60). All stents were deployed without post-dilatation. Periprocedural complications and mid-term outcomes were analyzed. RESULTS: The stroke rate was 2.3% within 30 days post-CAS (asymptomatic patients 1.5%; symptomatic patients 2.8%). Cerebral infarction occurred in one asymptomatic patient (1.5%) and one symptomatic patient (0.9%). Intracranial hemorrhage occurred in two symptomatic patients (1.9%). Post-CAS diffusion-weighted imaging (DWI) revealed a high-intensity area in 26 of 176 procedures (14.8%). Ipsilateral stroke after 31 days occurred in two patients (1.1%) and restenosis occurred in six (3.4%). A post-CAS comparison of the embolic protection devices revealed no difference in stroke incidence within 30 days and in DWI high-intensity area. CONCLUSIONS: Our CAS procedure without post-dilatation is feasible, safe and associated with a low incidence of stroke and restenosis.

Endovascular coiling as the first treatment strategy for ruptured pericallosal artery aneurysms: results, complications, and follow up.

We apply endovascular coiling as the first treatment option for ruptured pericallosal artery aneurysms. We conducted a retrospective analysis of the clinical and radiological outcomes of this treatment strategy and morphological factors associated with the success of endovascular coiling, to assess the safety and feasibility of our management strategy. From January 2003 to January 2012, we attempted endovascular coiling as the first-intention treatment for 30 consecutive patients with ruptured pericallosal artery aneurysms including those with intracerebral hematoma. Twenty-seven cases of ruptured pericallosal artery aneurysms were successfully embolized with coiling whereas three failures required surgery. Four patients experienced periprocedural complications including thromboembolic event in two and hematoma enlargement after coiling in two. A maximum aneurysm diameter of <3 mm was most strongly associated with failure of endovascular coiling. Of the 27 coil-treated aneurysms, immediate angiographic results showed complete aneurysm occlusion in 19 cases, neck remnant in 6, and residual aneurysm in 2. One patient had a major aneurysm recurrence that was uneventfully reembolized. Sixteen of our 30 patients had good outcomes (modified Rankin scale [mRS] 0-2), 7 had moderate disability (mRS 3), and 4 had severe disability (mRS 4-5) at 3 months after treatment. The management strategy for coiling as the first-intention treatment for ruptured pericallosal artery aneurysms has the potential to become an acceptable alternative to surgical clipping for selected cases, although a larger study population and longer follow-up periods are needed before definitive conclusions can be drawn.

New instrument for creating bone graft cavities for anterior cervical decompression and fusion: the anterior fusion spinal fork.

Sufficient bone decompression of osteophytes is important for positive functional outcomes in anterior cervical spine surgery. Achieving good alignment and bone fusion in anterior cervical decompression and fusion requires a bone graft bed of the optimum size and shape. We have developed a stainless steel instrument named the anterior fusion spinal fork, which is designed to aid in accurately drilling the bone cavity, thus enabling selection of the correct size of bone graft or bone graft substitutes. The device has an open design with 4 prongs, and resembles a three-dimensional fork. This instrument assists in guiding the direction of drilling, and marking the drilling point of the graft cavity with pyoctanin markers. We have used this instrument in 40 cases of anterior cervical spine surgery using the modified Smith-Robinson procedure since March 2000. This simple instrument allowed us to design and construct a bone graft cavity of the correct size and shape for iliac bone graft or bone graft substitutes for anterior cervical spine surgery.

[A case of non-traumatic direct carotid-cavernous fistula presenting with cerebral infarction].

A 76-year-old female presented with a rare case of cerebral infarction as a complication of non-traumatic direct carotid-cavernous fistula (CCF). She had left hemiparesis and magnetic resonance imaging revealed cerebral infarction in the right watershed area. Angiography showed a right high-flow direct CCF with total blood steal. Preoperative 123I-IMP SPECT revealed a hypoperfusion area in the region of the right anterior cerebral artery and right middle cerebral artery. In addition, she had double vision caused by abducens nerve palsy. Transarterial embolization of the fistula with endovascular trapping using detachable coils achieved complete obliteration of the right internal carotid artery and adequate flow reduction of the direct CCF. Postoperative angiography showed good filling of the collateral-flow via the posterior communicating artery without retrograde blood steal to the CCF. Her symptoms improved gradually after the procedure. Diffusion-weighted MR imaging obtained 8 days after the procedure revealed a few high signals in the right hemisphere, suggesting cerebral infarctions, but she presented no symptom. Postoperative 123 I-IMP SPECT showed an improvement of cerebral perfusion in the region of the right MCA posterior and left MCA. Cerebral ischemia caused by direct CCF is rare, and there are only a few reports of non-traumatic direct CCF presenting with cerebral infarction. This very rare case suggests that endovascular trapping is safe and useful as a treatment for direct CCF, especially in the case of an elderly patient with total blood steal.

Small unruptured intracranial aneurysm verification study: SUAVe study, Japan.

BACKGROUND AND PURPOSE: The natural history and optimal management of incidentally found small unruptured aneurysms <5 mm in size remain unclear. A prospective study was conducted to determine the optimal management for incidentally found small unruptured aneurysms. METHODS: From September 2000 to January, 2004, 540 aneurysms (446 patients) were registered. Four hundred forty-eight unruptured aneurysms <5 mm in size (374 patients) have been followed up for a mean of 41.0 months (1306.5 person-years) to date. We calculated the average annual rupture rate of small unruptured aneurysms and also investigated risk factors that contribute to rupture and enlargement of these aneurysms. RESULTS: The average annual risks of rupture associated with small unruptured aneurysms were 0.54% overall, 0.34% for single aneurysms, and 0.95% for multiple aneurysms. Patient <50 years of age (P=0.046; hazard ratio, 5.23; 95% CI, 1.03 to 26.52), aneurysm diameter of >or=4.0 mm (P=0.023; hazard ratio, 5.86; 95% CI, 1.27 to 26.95), hypertension (P=0.023; hazard ratio, 7.93; 95% CI, 1.33 to 47.42), and aneurysm multiplicity (P=0.0048; hazard ratio, 4.87; 95% CI, 1.62 to 14.65) were found to be significant predictive factors for rupture of small aneurysms. CONCLUSIONS: The annual rupture rate associated with small unruptured aneurysms is quite low. Careful attention should be paid to the treatment indications for single-type unruptured aneurysms <5 mm. If the patient is <50 years of age, has hypertension, and multiple aneurysms with diameters of >or=4 mm, treatment should be considered to prevent future aneurysmal rupture.