Endovascular treatment for dural arteriovenous fistula of the anterior condylar confluence involving the anterior condylar vein. A report of two cases.

SUMMARY: Anterior condylar confluence (ACC) dural arteriovenous fistula (AVF) is a rare anomaly. We describe two cases of ACC dural AVF involving the anterior condylar vein that were successfully treated with selective transvenous coil embolization. The first patient presented with headache and right pulse-synchronous tinnitus, and demonstrated abnormal flow medial to the jugular bulb within the right hypoglossal canal on source image of magnetic resonance angiography (MRA). Arterioangiography disclosed a dural AVF in this area, supplied mainly by the meningeal branches of the bilateral ascending pharyngeal artery. We diagnosed ACC dural AVF involving the anterior condylar vein and transvenous embolization was successfully performed. The second patient presented with right pulse-synchronous tinnitus. Views of source image of MRA and arterioangiography were similar to the first case and, again, transvenous embolization was successfully performed. ACC dural AVF is a rare condition and knowledge of the anatomy of the venous system around the craniocervical junction is required for successful treatment.

Risk stratification for in-hospital mortality in spontaneous intracerebral haemorrhage: a Classification and Regression Tree analysis.

BACKGROUND: Risk stratification for mortality in intracerebral haemorrhage (ICH) helps guide care, but existing clinical prediction rules are too cumbersome for clinical practice because of their complexity. AIM: To develop a simple decision tree model of in-hospital mortality risk stratification for ICH patients. METHODS: We collected information on spontaneous ICH patients hospitalized in a teaching hospital in Japan from August, 1998 to December, 2001 (n = 374). All variables were abstracted from data available at the time of initial evaluation. A prediction rule for in-hospital mortality was developed by the Classification and Regression Tree (CART) methodology. The accuracy of the model was evaluated using the area under receiver-operator characteristic curve. RESULTS: Overall in-hospital mortality rate was 20.2%. The CART methodology identified four groups for mortality risk, varying from low (2.1%) to high (58.9%). Level of consciousness (coma) was the best single predictor for mortality, followed by high ICH volume (cut-off 10.4 ml), and then age (cut-off 75 years). The accuracy of our CART model (0.86) exceeded that of a multivariate logistic regression model (0.81). DISCUSSION: ICH patients can easily be stratified for mortality risk, based on three predictors available on admission. This simple decision tree model provides clinicians with a reliable and practical tool.

[Diagnosis of acute phase of venous infarction by diffusion-weighted image: case report and review of the literature].

Diffusion-weighted imaging (DWI) can diagnose early stage not only of the arterial infarction but also of venous infarction. We successfully diagnosed a case as acute venous infarction by DWI. The patient, an infant of one year and ten months, presented disturbance of consciousness and left hemiparesis two weeks after dehydration and infections. Computed tomographic scan revealed a cerebral hemorrhage in the right parietal lobe. Cerebral angiography revealed no contrast filling of the posterior side of superior sagittal sinus, straight sinus and transverse sinus. DWI demonstrated a large hyperintensity lesion around the hematoma, suggesting venous infarction in the early stage. We thought that venous infarction was caused by secondary extension of thrombus to cerebral cortical veins and deep cerebral veins. External decompression and postoperative hypothermia therapy were performed because of rapidly deteriorating intracranial hypertension. Intracranial hypertension was, however, uncontrollable. The patient died four days after the onset. Diagnosis of the venous infarction by DWI was discussed along with other recent reports. Diffusion hyperintensity was displayed in almost all subjects with acute venous infarction. DWI pattern of venous infarction is more heterogeneous than that of arterial one because pathway from venous obstruction to infarction is complicated.

Thickening of sphenoid sinus mucosa during the acute stage of pituitary apoplexy.

The authors treated two patients with pituitary apoplexy in whom magnetic resonance (MR) images were obtained before and after the episode. Two days after the apoplectic episodes, MR imaging demonstrated marked thickening of the mucosa of the sphenoid sinus that was absent in the previous studies. The relevance of this change in the sphenoid sinus was investigated. Retrospective evaluations were performed using MR images obtained in 14 consecutive patients with classic pituitary apoplexy characterized by acute onset of severe headache. The mucosa of the sphenoid sinus had thickened predominantly in the compartment just beneath the sella turcica, in nine of 11 patients, as ascertained on MR images obtained within 7 days after the onset of apoplectic symptoms. This condition improved spontaneously in all four patients who did not undergo transsphenoidal surgery. The sphenoid sinus mucosa appeared to be normal on MR images obtained from three patients at the chronic stage (> 3 months after onset). The incidence of sphenoid sinus mucosal thickening during the acute stage was significantly higher in the patients with apoplexy than that in the 100 patients without apoplexy. A histological study conducted in four patients who underwent transsphenoidal surgery during the early stage showed that the subepithelial layer of the sphenoid sinus mucous membrane was obviously swollen. The sphenoid sinus mucosa thickens during the acute stage of pituitary apoplexy. This thickening neither indicates infectious sinusitis nor rules out the choice of the transsphenoidal route for surgery.

A modified burr-hole method in galeoduroencephalosynangiosis for an adult patient with probable moyamoya disease--case report and review of the literature.

A 49-year-old woman with probable moyamoya disease was surgically treated by combined direct and indirect methods, superficial temporal to middle cerebral artery anastomosis and galeoduroencephalosynangiosis by a burr-hole method developed by Kawamoto et al. Transient ischemic attacks and motor weakness of bilateral lower extremities disappeared completely within 1 month and never recurred during 1-year follow-up. Galeoduroencephalosynangiosis by a burr-hole method appears useful for preventing ischemic damage of the territory of the anterior cerebral artery in adult patients with probable moyamoya disease.

Quantitative MR evaluation of intracranial epidermoid tumors by fast fluid-attenuated inversion recovery imaging and echo-planar diffusion-weighted imaging.

BACKGROUND AND PURPOSE: Quantification of MR can provide objective, accurate criteria for evaluation of a given MR sequence. We quantitatively compared conventional MR sequences with fast fluid-attenuated inversion recovery (fast-FLAIR) and echo-planar diffusion-weighted (DW) MR imaging in the examination of intracranial epidermoid tumors. METHODS: Eight patients with surgically confirmed intracranial epidermoid tumors were examined with T1-weighted MR sequences, fast T2- and proton density-weighted dual-echo sequences, fast-FLAIR sequences, and DW echo-planar sequences. We measured the MR signal intensity and apparent diffusion coefficient (ADC) of epidermoid tumors, normal brain tissue, and CSF and calculated the tumor-to-brain and tumor-to-CSF contrast ratios and contrast-to-noise ratios (CNR). Results were compared among the five MR methods. RESULTS: On fast-FLAIR imaging, the mean signal intensity of epidermoid tumors was significantly higher than that of CSF but significantly lower than that of the brain; the contrast ratio and CNR of tumor-to-CSF were 4.71 and 9.17, respectively, significantly greater than the values with conventional MR imaging. On echo-planar DW imaging, epidermoid tumors showed a remarkably hyperintense signal relative to those of the brain and CSF; the mean contrast ratio and CNR of tumor-to-CSF were 13.25 and 19.34, respectively, significantly greater than those on fast-FLAIR or conventional MR imaging. The mean ADC of epidermoid tumors was 1.197 x 10(-3) mm(2)/s, significantly lower than that of CSF but higher than that of brain tissues. CONCLUSION: Fast-FLAIR imaging is superior to conventional MR imaging in depicting intracranial epidermoid tumors. Echo-planar DW imaging provides the best lesion conspicuity among the five MR methods. The hyperintensity of epidermoid tumors on echo-planar DW imaging is not caused by the diffusion restriction but by the T2 shine-through effect.

[Dissecting aneurysm of the anterior cerebral artery with persistent pearl & string sign on cerebral angiograms over a period of eight years].

We present a rare case of a dissecting aneurysm of the left anterior cerebral artery (ACA) with persistent pearl & string sign on cerebral angiograms over a period of 8 years. A 43-year-old woman with disturbance of consciousness and right sided hemiparesis was conservatively treated. Computed tomographic (CT) scan revealed a low-density area in the left frontal lobe. Initial angiography, which was performed at 6 months after the onset, showed a pearl & string sign at the A2 portion of the left ACA. After 8 years, repeat angiography again showed persistent pearl & string sign at the same portion of the left ACA. We discussed the changes in findings usually obtained in cerebral angiography concerning dissecting aneurysms in ACA.

Dissecting aneurysm of the peripheral posterior inferior cerebellar artery.

Dissecting aneurysms of intracranial posterior circulation have recently been shown to be less uncommon than previously thought. However, those involving the posterior inferior cerebellar artery (PICA) and not vertebral artery at all are extremely rare. We report here a case of a patient with a dissecting aneurysm of the lateral medullary segment of PICA which presented as subarachnoid haemorrhage. The aneurysm was treated by trapping surgery and the distant PICA was anastomosed to the occipital artery. The patient showed a slight ataxia immediately after surgery but recovered fully. Recovery from immediately postoperative cerebellar symptoms due to intra-operative ischemia seemed to be due largely to recovery of flow in the region of cortical branches of PICA.

Transsphenoidal "cross court" approach using a slightly modified speculum to reach pituitary adenomas with lateral growth.

BACKGROUND: The purpose of this study was to evaluate the usefulness of an oblique "cross court" transsphenoidal approach using a speculum with slightly modified projections for pituitary adenomas showing lateral extension. METHOD: The projection of the speculum on the side of the cavernous lesion was shortened by 5 mm. The tip of the longer projection was placed in the sphenoid sinus, while the end of the shorter projection was placed on the concha sphenoidalis. An oblique transsphenoidal view was then easily obtained by opening the speculum. The contralateral nasal incisura had to be widened in some cases to achieve a more oblique view. FINDINGS: Twenty-eight patients diagnosed with pituitary adenoma showing lateral growth underwent adenomectomy under direct observation of the medial portion of the cavernous sinus using this approach. Postoperative normalization of hyperendocrinopathy or gross total removal of the tumour was achieved in the majority of patients. INTERPRETATION: An oblique transsphenoidal approach using this speculum and contralateral minor maxillary osteotomy afforded a direct view of the medial cavernous sinus, sufficient for the removal of adenomas showing minor to moderate lateral growth.

[Two cases with coil embolization following incomplete neck clipping].

We report two cases with embolization (coil embolization) using Guglielumi detachable coils of residual aneurysms following incomplete neck clipping. The first case, a 75-year-old woman suffered from a subarachnoid hemorrhage due to the rupture of a left internal carotid posterior communicating aneurysm in June, 1997. Neck clipping of the aneurysm was performed at day 1. Follow-up angiogram at day 7 showed a residual aneurysm involving the dome of the initial aneurysm. We performed coil embolization of the residual aneurysm following the angiogram. Almost complete obliteration of the aneurysm lasted during the follow-up period of two and a half years. The second case, a 71-year-old woman suffered from a subarachnoid hemorrhage due to the rupture of a right internal carotid posterior communicating aneurysm in May, 1999. Neck clipping of the aneurysm was performed at day 1. Follow-up angiogram at day 7 showed a residual aneurysm involving only a part of the initial aneurysm near the neck. Because no spontaneous thrombosis of the residual aneurysm was obtained after 2 months, we performed coil embolization of the residual aneurysm. Almost complete obliteration of the aneurysm lasted during the follow-up period of 7 months. These patients were discharged with good performance status. We consider the morphologic feature of the residural aneurysm to be most important for determining when to perform coil embolization of such residual aneurysms.

Size-adjustable titanium plate for reconstruction of the sella turcica. Technical note.

A size-adjustable plate constructed of pure titanium is proposed for use in the reconstruction of the sella turcica. The plate is composed of two semicircular pieces that are connected by a hinge located at the top of the plate. Using an applicator, the plate is inserted into the sella turcica in a closed position. The same applicator is then used to open and secure the plate. The titanium causes minimal ferromagnetic artifacts on postoperative magnetic resonance imaging. Preliminary findings indicate a possible clinical use for this plate in the reconstruction of the sella turcica when no suitable piece of bone is available.

The relationship between magnetic resonance imaging findings and clinical manifestations of hypothalamic hamartoma.

OBJECT: Hypothalamic hamartoma is generally diagnosed based on its magnetic resonance (MR) imaging characteristics and the patient's clinical symptoms, but the relationship between the neuroradiological findings and clinical presentation has never been fully investigated. In this retrospective study the authors sought to determine this relationship. METHODS: The authors classified 11 cases of hypothalamic hamartoma into two categories based on the MR findings. Seven cases were the "parahypothalamic type," in which the hamartoma is only attached to the floor of the third ventricle or suspended from the floor by a peduncle. Four cases were the "intrahypothalamic type," in which the hamartoma involved or was enveloped by the hypothalamus and the tumor distorted the third ventricle. Six patients with the parahypothalamic type exhibited precocious puberty, which was controlled by a luteinizing hormone-releasing hormone analog, and one patient was asymptomatic. No seizures or mental retardation were observed in this group. All patients with the intrahypothalamic type had medically intractable seizures, and precocious puberty was seen in one. Severe mental retardation and behavioral disorders including aggressiveness were seen in two patients. The seizures were controlled in only one patient, in whom stereotactically targeted irradiation of the lesion was performed. This topology/symptom relationship was reconfirmed in a review of 61 reported cases of hamartoma, in which the MR findings were clearly described. The parahypothalamic type is generally associated with precocious puberty but is unaccompanied by seizures or developmental delay, whereas the intrahypothalamic type is generally associated with seizures. Two thirds of patients with the latter experience developmental delays, and half also exhibit precocious puberty. CONCLUSIONS: Classification of hypothalamic hamartomas into these two categories based on MR findings resulted in a clear correlation between symptoms and the subsequent clinical course.

[Significance and pitfall of diffusion weighted image in super acute cerebral ischemia: investigation by questionnaire study].

We investigated the findings in diffusion weighted image (DWI) of super acute ischemia examined within 6 hours after onset by questionnaire study. The magnitude of magnetic field of MR machine, method of diffusion weighted imaging, the total number of cases, the number of cases with high signal intensity area on DWI and the number of decrease or disappearance of signal intensity were investigated. Answers were obtained from 16 institutes (64%). Totally, 232 cases of super acute ischemia examined within 6 hours after onset were imaged by DWI. High signal intensity area were detected in 189 cases (81.5%) of all, which disappeared or decreased in 10 cases (4.3%). Follow up DWI revealed a decrease in the area of high signal intensity in 5 (17.9%) of 28 cases who underwent thrombolysis by endovascular treatment. However, 6 (21.4%) or 28 cases resulted in hemorrhagic infarction. We must recognize the diffusion anisotropy, apparent diffusion coefficient, and b value in reading the DWI. In conclusion, high signal intensity area on DWI include not only irreversible infarction but also the reversible ischemia.

Brain metastasis of Merkel cell carcinoma. Case report and review of the literature.

Merkel cell carcinoma (MCC) is a rare primary cutaneous neuroendocrine tumor that is locally aggressive and has potential for metastatic spread. However, brain metastases are rare, and therapy for such tumors has never reported. The authors present a 48-year-old woman with MCC of the left elbow and a right cerebellar metastasis. After the right cerebellar mass was totally resected, radiation treatment and chemotherapy were performed. Eight cases of brain metastasis have been reported in the literature, but only 5 have been presented in sufficient detail for analysis. Therapy for brain metastases has always been palliative whole-brain irradiation and chemotherapy except for our patient, who underwent total removal of the tumor and survived for 11 months without neurological deficit. Except in the case of 1 with a particularly radiosensitive MCC, the patients with brain metastases died within 9 months after detection of the brain lesions. If possible, aggressive excision of brain metastases as well as of the primary lesion should be done.

Apoptosis following gamma knife radiosurgery in a case of acoustic schwannoma.

A 25-year-old woman with a large acoustic schwannoma underwent surgical excision 18 months after Gamma Knife radiosurgery because of transient expansion of the tumor causing ataxia. Histopathologial investigation by the TUNEL method revealed the presence of some apoptotic cells. The findings were compared with findings from a control group of 7 operated cases where radiosurgery had not been used. There was no apoptosis found in any of these cases. In addition, another case which resulted in a regrowing tumor following Gamma Knife treatment also showed no apoptosis. These findings suggest apoptosis may be a possible mechanism in reducing tumor size following Gamma Knife radiosurgery.

[Multivariate analysis of intentional temporary vessel occlusion in aneurysmal surgery].

Temporary vessel occlusion (TO) for aneurysmal clipping is an effective technique to facilitate dissection between aneurysm and parent vessels, and to place a permanent clip at the aneurysmal neck precisely. However, several unsolved problems remain regarding the overall safety and risk resulting from this technique. The authors examined a series of patients in whom mannitol 500 ml, tocopherol acetate 500 mg, and phenytoin 500 mg were administered intravenously as ischemic protection during TO for the aneurysmal clipping. The study comprises a nonconcurrent retrospective analysis of 144 consecutive aneurysm clippings performed with the aid of intentional TO at the Hiroshima Prefectural Hospital from 1985 to 1995. To identify technical and patient-specific risk factors for perioperative stroke, factors studied included duration, location of the temporary clip application, number of occlusive episodes, patient sex, age, and preoperative neurological status, timing of operation, as well as postoperative, temporary or permanent, neurological deficits (ND) due to TO were used. Overall frequency of postoperative ND due to TO manifested clinically and radiologically were 9.0% and 9.7%, respectively. In both univariate and multivariate analysis there were no significant factors relevant to the ND. However, duration of the temporary occlusion time over 20 minutes was the factor most influential on the ND due to TO. Duration of the temporary occlusion time was shown to have no link with outcome. Based on our findings the authors conclude that temporary vessel occlusion within 20 minutes with anti-ischemic drugs is a relatively safe adjunct to aneurysmal surgery.

Usefulness of two-dimensional time-of-flight MR angiography combined with surface anatomy scanning for convexity lesions.

Thirty-eight patients with convexity lesions were studied prospectively with the two-dimensional time-of-flight (2D-TOF) magnetic resonance angiography (MRA) method. Of these 21 cases had additional surface anatomy scanning (SAS) and 7 cases had three-dimensional phase contrast (3D-PC) MRA. The findings were compared during surgery and the predictability of 2D-TOF evaluated. 2D-TOF was obtained with 2 mm slice thickness after the administration of contrast media for routine magnetic resonance imaging (MRI). Cortical veins were visualized with a good resolution with a scan time of only 5 minutes. The tumor was also visible in the background, due to enhancement, and thus the tumor-vessels relation was shown. Slow-flow vessels were also adequately seen. SAS was done at the same sitting with fast spin echo (FSE) with a scan time of 3 minutes. Once both images were incorporated, information on gyri and their relation to the lesions and vasculature could be obtained from a single image. We found 2D-TOF alone, or at times in combination with SAS, useful for planning of operation for convexity lesions.

Usefulness of three-dimensional phase contrast MR angiography on arteriovenous malformations.

Prospective three-dimensional phase contrast (3D-PC) MR angiography was obtained in 34 patients with arteriovenous malformations (AVM) and comparison was made between digital substraction angiography (DSA) and three-dimensional time-of-flight (3D-TOF) methods. Velocity encoding (VENC) for 3D-PC was adjusted to 60 and 10 cm/sec., and was changed only when adequate information was not obtained. VENC 60 cm/sec, demonstrated the main feeders in 100% of cases and the nidus in 86% of cases whereas VENC 10 cm/sec. showed the draining vein in 78% of cases. The detection rate of feeder, nidus and drainer was 60%, 40% and 13% respectively by the TOF technique. The mean size of the nidus as compared with DSA as standard was 130% with MRI, 108% with 3D-PC and 92% with the TOF technique and this difference was not statistically significant. 3D-PC was clearly superior in detecting AVM in the presence of hemosiderin, hematoma or surgical clips. It also showed gradual disappearance of the lesion after radiosurgery. We found 3D-PC superior to 3D-TOF in the diagnosis, therapeutic planning and follow-up of AVM.

[A case of Rathke's cleft cyst in association with anterior communicating artery aneurysm presenting a rare visual field defect].

We report a case of Rathke's cleft cyst associated with anterior communicating artery aneurysm. The patient was 60-year-old woman who developed visual disturbance two months before admission to our hospital. Visual acuity on the right was 0.06 and on the left was 0.08. The visual fields showed a complete temporal hemianopsia on the left eye and an incomplete temporal hemianopsia of the right eye with a central defect of the temporal visual field. CT and MR imagings showed an intra- and suprasellar mass lesion with no enhancement. Angiography showed bilateral A1 elevations and anterior communicating artery aneurysm. The operation was performed through interhemispheric approach. Suprasellar cystic mass compressed upward the optic nerves and chiasm, and aneurysmal dome stuck in the central region of chiasm. This anatomical disorders affected to the optic chiasm resulted in a rare visual field defect. Neck clipping of aneurysm and opening of the cyst were performed. A diagnosis of Rathke's cleft cyst was made. Following surgery, her visual fields resolved but she suffered from diabetes insipidus.