Pathophysiological evaluation of cerecyte coil embolization for experimental broad neck aneurysms.

Cerecyte second-generation coils feature inner surfaces coated with an absorbable polyglycolic acid (PGA) polymer. Their use is expected to accelerate aneurysm organization, but time course data are limited. The present experimental study was therefore conducted to clarify the processes by pathological examination. Methods. Two types of experimental aneurysms were initially generated in adult mongrel dogs, one bifurcation and another of lateral wall type. Long-term persistence of each was defined by follow-up angiography for more than 1 year. Embolization of the aneurysms was then performed using only cerecyte coils, and follow-up angiography was conducted after 2 and 4 weeks followed by pathological examination. Results. Organization of both types of broad neck aneurysm was apparent 4 weeks after embolization, which is earlier as compared with already reported data for bare coils.

Altered hemodynamics associated with pathogenesis of the vertebral artery dissecting aneurysms.

The etiology of the vertebral dissecting aneurysms is largely unknown, and they frequently occurs in relatively healthy young men. Objectives and Methods. A series of 57 consecutive cases defined by angiography were evaluated with regard to deviation in the course of the affected and contralateral vertebral arteries. Division was into 3 types: Type I without any deviation, Type II with mild-to-moderate deviation but not over the midline; and Type III with marked deviation over to the contralateral side beyond the midline. Results. The most frequent type of VA running was Type III for the affected and Type I nonaffected side, with this being found in all 17 patients except one. All of the Type III dissections occurred just proximal to a tortuous portion, while in cases with Type-I- and Type-II-affected sides, the majority (33 of 39) occurred near the union of the vertebral artery. In 10 of 57, a non-dominant side was affected, all except one being of Type I or II. With 12 recent patients assessed angiographically in detail for hemodynamics, eleven patients showed contrast material retrograde inflowing into the pseudolumen from the distal portion of the dissection site. Turbulent blood flow was recognized in all of these patients with retrograde inflow. Conclusions. Turbulent blood flow is one etiology of vertebral artery dissection aneurysms, with the sites in the majority of the cases being just proximal to a tortuous portion or union of vessels. In cases with dissection proximal to the tortuous course of the vertebral artery, retrograde inflow will occur more frequently than antegrade, which should be taken into account in designing therapeutic strategies.

A new transvenous approach to the carotid-cavernous sinus via the inferior petrooccipital vein.

OBJECT: The transvenous approach via the inferior petrosal sinus (IPS) is commonly used as the most appropriate for carotid-cavernous fistula (CCF) or cavernous sinus sampling. However, sometimes the IPS is not accessible because of anatomical problems and/or complications, therefore an alternative route is needed. In this paper, the authors present and discuss the utility of a transvenous approach to the cavernous sinus via the inferior petrooccipital vein. METHODS: Four patients, 3 with dural CCFs and the other with Cushing disease, in whom endovascular surgical attempts failed using a conventional venous approach via the IPS, underwent a transvenous approach to the cavernous sinus via the inferior petrooccipital vein (IPOV). One dural CCF case had only cortical venous drainage, the second CCF also mainly drained into the cortical vein with slight inflow into the superior ophthalmic vein and inferior ophthalmic vein, and the third demonstrated drainage into the superior and inferior ophthalmic veins and IPOV. RESULTS: In all cases, the cavernous sinus could be accessed successfully via this route and without complications. CONCLUSIONS: The transvenous approach to the cavernous sinus via the IPOV should be considered as an alternative in cases when use of the IPS is precluded by an anatomical problem and there are no other suitable venous approach routes.

Efficacy of endovascular surgery for ruptured aneurysms with vasospasm of the parent artery.

INTRODUCTION: In the presence of vasospasm it is recommended that surgical clipping for a ruptured aneurysm should be delayed until it disappears, but this may be associated with re-rupture of the aneurysm resulting in a poor outcome. The indications for endovascular coil embolization in such cases are discussed. METHODS: Since November 2002, endovascular coil embolization has been used in 18 consecutive patients with ruptured aneurysm with vasospasm of the parent artery ranging from 2 to 28 days (mean 9 days) after the initial subarachnoid hemorrhage. After successful obliteration of the aneurysm, a microcatheter preceded by a guidewire was introduced into the peripheral vessels with vasospasm of the A2 or M2 portions in order to release the vasospasm mechanically. RESULTS: Endovascular procedures were performed successfully in all but one of the cases (94%), resulting in complete occlusion in 14 of 17 patients and mild dilation of the vasospasm in all 17 patients without technical complications or re-rupture of the aneurysm. In the one case of failure because of a tortuous artery, surgical clipping was performed after disappearance of the vasospasm. Cerebral infarction occurred in four patients, but only one correlated with the distribution of catheterization and the neurological deficits had completely disappeared 3 months after the onset. CONCLUSION: Catheterization of parent vessels in cases of vasospasm is safe for coiling and also mechanically releases vasospasm. Vasospasm of M2 and A2 segments can be treated with microcatheterization only.

Contrast stasis in large and giant internal carotid artery aneurysms as a good prognostic factor for endovascular coil embolization: retrospective study.

OBJECTIVE: Before treatment for large and giant aneurysms, we need some of the predictors to prognose a good result. In this retrospective study, we attempted to determine criteria such as angiographic signs to identify good candidates for effective endovascular surgery. METHODS: This study involved 45 patients with large or giant aneurysms treated by endovascular embolization. For angiographic study, we delivered a bolus injection of contrast medium. All aneurysms were confirmed angiographically and the morphology was defined in detail before endovascular embolization. We divided the patients into two groups based on angiographic findings. Group A (n=16) manifested stasis of the contrast medium in the aneurysm on venous phase. Group B (n=29) exhibited other findings. We retrospectively evaluated the relationship between stasis of the contrast medium in the aneurysm and results of endovascular embolization. RESULTS AND DISCUSSION: There was no significant difference between the two groups with respect to the size of the aneurysm. However, the neck/dome ratio (P=0·04) and size of the neck (P=0·003) were significantly different between groups A and B. The morphological outcome was better in group A than group B (P=0·03). We demonstrate that contrast stasis is a good predictor of outcome in patients with large or giant aneurysms to consider the endovascular embolization. Hemodynamic studies on large patient populations may reveal other factors predictive of a good treatment outcome.

Anterior-wall aneurysm of the internal carotid artery successfully treated solely by stenting: With special reference to etiology.

In this case, a ruptured anterior wall aneurysm of the internal carotid artery disappeared on angiography immediately after stent placement. We focus on the underlying nature of the lesion and this possible alternative treatment.

Dural arteriovenous fistulas in the cavernous sinus: clinical research and treatment.

Introduction. The purpose of this paper is to clarify the clinical course, with the dural carotid cavernous fistula (CCF), featuring a pallet of symptoms, paying special attention to radiological findings. Methods. Seventy-six consecutive patients with dural CCFs were investigated in detail, all of whom were defined by angiography. Results. The most common initial symptom was diplopia in 47 patients (62%) and the most frequently observed on arrival were type II, featuring cranial nerve palsies followed by the classical triad in 27, and then type I only with cranial nerve palsies. The time until admission with type I (mean: 6.7 W ± 6.0) was significantly shorter than that with type II (mean: 25.1 W ± 23.5). Branches from bilateral carotid arteries widely inflowing into bilateral carotid cavernous sinus were present in 30 (39%), 20 (26%) of which also demonstrated direct inflow into the intercavernous sinus. type I and II had more multiple venous drainage routes as compared with type III (classical triad only on arrival) and IV (initial development of the classical triad followed by cranial nerve palsy). Conclusion. In our series of dural CCF patients, the most common initial symptom was cranial nerve palsy, mostly featuring multiple venous drainage including cortical drainage. Such palsies should be added to the classical triad as indicative symptoms. Bilateral carotid arteries often inflow into cavernous and intercavernous sinuses, which should be taken into account in choice of therapeutic strategy.

Compensation of intraoperative transcranial motor-evoked potential monitoring by compound muscle action potential after peripheral nerve stimulation.

It is often difficult to evaluate the results of transcranial motor-evoked potential (TCMEP) monitoring in patients under general anesthesia because these results are strongly affected by anesthetics and muscle relaxants. To exclude effects of muscle relaxants on TCMEP, compound muscle action potential (CMAP) by supramaximum stimulation of the median nerve immediately after transcranial stimulation (300 to 600 V) was recorded in 70 neurosurgical operations. A relative amplitude index (RAI) was defined as the amplitude of TCMEP after the operative procedure divided by the amplitude of TCMEP before the operative procedure. The RAI was calculated and was compensated by the amplitude of CMAP in 141 limbs. In 12 limbs of 7 patients with postoperatively progressed motor paresis, the compensated RAI was less than 0.2. The compensated RAI in all other 129 limbs of 63 patients without postoperative motor palsy was more than 0.2. These results suggest that compensation of TCMEP monitoring by CMAP is an easy and accurate method for removing the effects of muscle relaxants in TCMEP.

Blurred vision caused by inflammation of the optic nerves due to a pituitary abscess.

A 48-year-old woman was admitted to our institution complaining of headache and a 2-month history of blurred vision and increased urinary volume. T(1)-weighted magnetic resonance (MR) imaging with gadolinium showed a ring-enhanced mass lesion in the pituitary. Fluid-attenuated inversion recovery MR imaging showed high-intensity lesions in the optic nerves, hypothalamus, and thalamus. The histological diagnosis was pituitary abscess. The blurred vision was caused by inflammation, but not compression, of the optic nerves due to the pituitary abscess outside the hypophysis.

Glioblastoma multiforme metastasis to the axis. Case report.

Extracranial bone metastasis from glioblastoma multiforme (GBM) has rarely been reported in the literature, and most metastatic GBMs are multiple bone metastases. The authors describe the first case of a GBM with metastasis only to the axis. This 42-year-old man presented with a 2-month history of headache, nausea, vomiting, and disorientation. Magnetic resonance imaging demonstrated a right temporal tumor, which was diagnosed as a GBM based on tumor resection. The patient was treated using radiation (6000 cGy) and the intravenous administration of nimustine hydrochloride. Eighteen months thereafter, he experienced the sudden onset of neck pain. Magnetic resonance studies revealed a tumor in the axis that was diagnosed as GBM based on biopsy procedure.

Biopsy of brain stem glioma using motor-evoked potential mapping by direct peduncular stimulation and individual adjuvant therapy. Case report.

A 23-year-old man presented with a brain stem glioma manifesting as a 6-month history of right hemiparesis and diplopia. Serial magnetic resonance imaging showed an intrinsic diffuse brain stem glioma that gradually localized to the left cerebral peduncle after initial adjuvant therapy. Surgery was performed through a left subtemporal transtentorial approach under motor-evoked potential (MEP) mapping by direct peduncular stimulation. The lateral aspect of the midbrain was exposed, a train of five bipolar 25 mA pulses was applied, and MEPs recorded from the extremities. MEPs were only recorded from the left extremities even with left cerebral peduncular stimulation. Partial resection of the tumor was safely performed, with slight temporary neurological worsening. The histological diagnosis was anaplastic astrocytoma. Individual adjuvant therapy based on the results of real-time reverse transcription-polymerase chain reaction of O6-methylguanine-deoxyribonucleic acid methyltransferase achieved an almost complete tumor response. Surgery under pyramidal tract mapping and intensive postoperative adjuvant therapy resulted in a good outcome despite the presence of a generally intractable intrinsic brain stem glioma.

Prolactinoma with a high adrenocorticotropic hormone level caused by meningitis--case report.

A 69-year-old man was admitted semicomatose with high-grade fever and meningeal signs. Magnetic resonance imaging showed a supra- and intrasellar lesion. Hormone studies on admission showed increased serum prolactin, adrenocorticotropic hormone (ACTH), and cortisol titers. However, the serum ACTH and cortisol levels returned to normal after treatment of meningitis with an antimicrobial agent. The histological diagnosis was pituitary adenoma. Immunohistological staining showed positive reaction for prolactin but not for ACTH. This is a rare case of prolactinoma with a high serum ACTH level caused by meningitis.

Nevoid Basal cell carcinoma syndrome with medulloblastoma and meningioma--case report.

A 35-year-old man presented with a rare case of nevoid basal cell carcinoma syndrome, or Gorlin's syndrome, associated with both medulloblastoma and meningioma, manifesting as visual field constriction due to multiple parasellar tumors. He had undergone resection of a medulloblastoma at the age of 1 year 9 months, followed by adjunctive irradiation with a total dose of 40 Gy. He presented with multiple subcutaneous nodules on his face and neck. Histological examination of biopsy specimens established the diagnosis of nevoid basal cell carcinoma syndrome. Tuberculum sellae meningioma was removed through a craniotomy, and his symptoms improved. Meningioma is known to occur in the field of therapeutic irradiation, so chemotherapy may be a better option for medulloblastoma associated with nevoid basal cell carcinoma syndrome.

Late-onset multiple sclerosis mimicking brain tumor: a case report.

Multiple sclerosis (MS) is a demyelinating disease that predominantly affects those aged in their twenties to their forties. We recently observed a case of rapidly progressive late-onset MS in an elderly patient with a large, single lesion on magnetic resonance imaging (MRI), which was difficult to distinguish from a brain tumor. This case is reported here with a review of the literature. A 69-year-old woman who presented with left hemiparesis was admitted to our institute. A tumor lesion was strongly suspected from the MRI finding of a large solitary lesion adjacent to the right lateral ventricle. Her left hemiparesis became rapidly worse, so we decided to perform stereotactic biopsy. Histopathological examination indicated that the patient had a demyelinating disease such as multiple sclerosis. Steroid pulse therapy was started after the operation and led to a marked improvement of the symptoms. With follow-up for more than 1 year after discharge, she has shown no sign of relapse. Late-onset MS should be suspected if edema or mass effect is not visualized around the lesion on MRI, bearing in mind that late-onset MS can have a progressive course in elderly patients.