Fumihiro Sakakibara

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.

A Ruptured Aneurysm Located at a Collateral Artery That Extended From the Proximal A2 Segment to the M1 Segment, Associated With an Anomalous Branch of the Anterior Choroidal Artery and Middle Cerebral Artery Hypoplasia: Case Report

We here describe the first case of a ruptured aneurysm located at a collateral artery that extended from the proximal A2 segment to the M1 segment, which was associated with an anomalous branch of the anterior choroidal artery and middle cerebral artery (MCA) hypoplasia. The aneurysm was revealed by angiograms and intraoperative findings. No previous accounts have been published of such an extremely rare vessel anomaly. In practice, this case highlights the urgent need to preoperatively recognize such vascular anomalies, as well as to better understand the collateral blood supply in cerebral ischemia associated with these MCA anomalies. Such knowledge will be helpful for planning optimal surgical procedures.

Chronic Encapsulated Intracerebral Hematoma Associated with Cavernous Malformation

Chronic encapsulated intracerebral hematoma (CEIH) is a rare cerebrovascular disease that behaves as a slowly expanding lesion with a gradual onset. It is well established that CEIH is associated with arteriovenous malformations; however, CEIH associated with cavernous malformation (CM) is extremely rare. We herein report a case of CEIH associated with CM, and discuss its pathogenesis. A 12-year-old female was admitted to our hospital because of a one week history of progressive headache and nausea. Brain computed tomography scan and magnetic resonance imaging showed an intracerebral hematoma surrounded by edema in the right frontal lobe. One week later, her headache and nausea worsened, and a brain computed tomography scan revealed the enlargement of hematoma. A right frontal craniotomy was performed. The capsule, mass, and hematoma were totally removed. Histological examination confirmed the diagnosis of CEIH associated with CM. Immunohistochemical analysis revealed increased expression of vascular endothelial growth factor (VEGF) and the VEGF receptor-1 in the endothelium and fibroblasts. Our findings suggest that the activated VEGF pathway might have positively contributed to development of CEIH in the present patient.

Anterior cerebral artery dissecting aneurysm associated with untreated craniopharyngioma

Abstract Coexistence of cerebral aneurysm and untreated craniopharyngioma is extremely rare. We present an extremely rare case of anterior cerebral artery dissecting aneurysm associated with untreated craniopharyngioma, and discuss the relationship between these two lesions.

Radiological factors related to recurrence of chronic subdural hematoma

We read with great interest the article titled “Use of twistdrill craniostomy with drain in evacuation of chronic subdural hematomas: independent predictors of recurrence” by Escosa et al. [1]. The authors analyzed factors related to the recurrence of hematoma in 312 consecutive patients with chronic subdural hematoma (CSDH) who were treated with twist-drill craniostomy (TDC) with a drain. They measured the radiological parameters of CSDH, namely, hematoma width, midline shift, and hematoma side, before and after the operation, and concluded that preoperative and postoperative hematoma width and midline shift are independent predictors of recurrence. We completely agree with the viewpoint of Escosa et al., and we wish to provide further comment on this issue. Nakaguchi et al. [3] reported that they classified CSDHs into four types according to the internal architecture and density of hematomas, and defined the “separated type” as a hematoma containing two components of different densities separated by a clear boundary—that is, a lower density component located above a higher density component. Among all the CSDH types, the separated type had the highest recurrence rate (36%), as reported by some previous studies [2, 4]. We have also reported the recurrence rates in 64 consecutive patients after CSDH evacuation [5]. Recurrence was noted in seven of the 64 (10.9%) patients after burr-hole craniostomy with a drain, and the separated type of CSDH was seen in three (42.9%) of the seven recurrent cases. Furthermore, Nomura et al. [4] analyzed the concentrations of fibrinogen, fibrin monomer, and d-dimer in patients with “layering-type” CSDH, which is equivalent to the separated type, and reported that the layering type of CSDH is active, has a high tendency to rebleed, and exhibits hyperfibrinolytic activity. Based on these reports, we consider that further investigation to determine the correlation of internal architecture and density of hematomas with the recurrence of CSDH may provide additional insight into the recurrence of CSDH after TDC with a drain.

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.

Reverse bypass using a naturally formed "bonnet" superficial temporal artery in symptomatic common carotid artery occlusion: a case report.

We herein describe a patient with symptomatic common carotid artery occlusion who underwent a reverse superficial temporal artery (STA)-middle cerebral artery (MCA) single bypass using a naturally formed “bonnet” STA. The surgical procedure was performed without difficulty, and no further neurological deterioration was observed after surgery. In practice, this case highlights that the reverse STA-MCA bypass can be achieved safely and less invasively using a naturally formed “bonnet” STA.

A surgical case of paraclinoid carotid aneurysm associated with ipsilateral cervical internal carotid artery dissection

This report presents a 60-year-old with a large paraclinoid carotid aneurysm associated with cervical interal carotid artery (ICA) dissection (CICAD). She had a fall while riding a bicycle and hit her head on the ground. Computed tomography scan done at another facility showed a round mass lesion near the sella. Her medical history revealed gradual decrease in left eye vision since two years. Left carotid artery digital subtraction angiography demonstrated a CICAD with an intimal flap and a large paraclinoid aneurysm (15.5 mm in size). She underwent a high-flow bypass with a so-called double-insurance bypass and proximal ligation of the cervical ICA and the postoperative course was uneventful. She was discharged without any new neurological deficits. We suggest that the possible nature of carotid artery dissection (CAD)-related hemodynamic changes should be taken into consideration in cases of intracranial aneurysm associated with CAD.

Vestibular schwannoma with repeated intratumoral hemorrhage

Repeated hemorrhage from a vestibular schwannoma is very rare. We report a 15-year-old male, to our knowledge the fourth known patient with repeated hemorrhage of vestibular schwannoma, who presented with rapidly progressive right-sided hearing loss and tinnitus. MRI showed a mass lesion in the right cerebellopontine angle. T1-weighted and T2-weighted MRI revealed a hyperintense intratumoral area, indicating subacute hemorrhage within the tumor. Nine weeks after the initial onset, the patient again presented with a sudden onset headache, nausea, and ataxia. A CT scan showed recurrence of an intratumoral hemorrhage. A subtotal resection was achieved. A histopathological examination of the resected specimen showed typical features of schwannoma. We review the pertinent literature and discuss the features of repeated hemorrhage from a vestibular schwannoma.

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.