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.

Development of the PHASES score for prediction of risk of rupture of intracranial aneurysms: a pooled analysis of six prospective cohort studies.

BACKGROUND: The decision of whether to treat incidental intracranial saccular aneurysms is complicated by limitations in current knowledge of their natural history. We combined individual patient data from prospective cohort studies to determine predictors of aneurysm rupture and to construct a risk prediction chart to estimate 5-year aneurysm rupture risk by risk factor status. METHODS: We did a systematic review and pooled analysis of individual patient data from 8382 participants in six prospective cohort studies with subarachnoid haemorrhage as outcome. We analysed cumulative rupture rates with Kaplan-Meier curves and assessed predictors with Cox proportional-hazard regression analysis. FINDINGS: Rupture occurred in 230 patients during 29,166 person-years of follow-up. The mean observed 1-year risk of aneurysm rupture was 1·4% (95% CI 1·1-1·6) and the 5-year risk was 3·4% (2·9-4·0). Predictors were age, hypertension, history of subarachnoid haemorrhage, aneurysm size, aneurysm location, and geographical region. In study populations from North America and European countries other than Finland, the estimated 5-year absolute risk of aneurysm rupture ranged from 0·25% in individuals younger than 70 years without vascular risk factors with a small-sized (<7 mm) internal carotid artery aneurysm, to more than 15% in patients aged 70 years or older with hypertension, a history of subarachnoid haemorrhage, and a giant-sized (>20 mm) posterior circulation aneurysm. By comparison with populations from North America and European countries other than Finland, Finnish people had a 3·6-times increased risk of aneurysm rupture and Japanese people a 2·8-times increased risk. INTERPRETATION: The PHASES score is an easily applicable aid for prediction of the risk of rupture of incidental intracranial aneurysms. FUNDING: Netherlands Organisation for Health Research and Development.

[Rupture of an internal carotid-posterior communicating artery aneurysm formerly presented with transient pupil-sparing oculomotor nerve palsy in an extremely elderly patient].

We recently encountered experienced a rare case of transient pupil-sparing oculomotor nerve palsy(PSONP)caused by an aneurysm at the junction of the internal carotid-and posterior communicating arteries(IC/PC AN)in an 87-year-old, non-diabetic woman. She initially presented with diplopia 4 years previously, and was diagnosed, based on incomplete right oculomotor paresis without pupil involvement(PSONP), as external ophthalmoplegia. MR-angiography revealed a long protrusion of the IC/PC AN with posterior-inferior projection, for which she chose to receive conservative management. Thirty nine months later, she presented with another transient PSONP. CT angiography(CTA)showed that the aneurysm was enlarged in the posterior-inferior direction. Two days after this last CTA imaging, the aneurysm ruptured with upward enlargement of the bleb. Despite complete external ophthalmoplegia and ptosis, her pupil involvement was still minimal and transient. By reviewing reported cases and our own case, we found that a narrow and long aneurysm body and posterior-inferior projection are characteristic for the IC/PC AN that causes PSONP, implying a possible mechanism for PSONP by upward compression of the oculomotor nerve. Though rare in its incidence, IC/PC AN could present with PSONP prior to their rupture. Therefore, immediate imaging evaluation in patients presenting with PSONP is essential to prevent devastating rupture events.

Ruptured intracranial aneurysms in pediatric polyarteritis nodosa: case report.

Polyarteritis nodosa (PAN) is a rare, systemic necrotizing vasculitis of small and medium size arteries that leads to aneurysms in various organs. Aneurysms associated with PAN are common in visceral arteries, however, intracranial aneurysms are rare, especially in childhood. A pediatric patient with PAN developed serial hemorrhagic strokes from a ruptured superior cerebellar artery aneurysm (subarachnoid hemorrhage) and a de novo aneurysm of the frontoorbital artery (intracerebral hemorrhage) after 9 months. Patients with PAN who present with intracranial aneurysms are candidates for intervention even if the aneurysm is unruptured and still small, and close observation is needed to detect de novo aneurysms in patients with chronic history of PAN.

[Spontaneous dissection of the anterior cerebral artery that simultaneously presented with cerebral infarction and subarachnoid hemorrhage, successfully treated with conservative management: a case report].

We recently encountered a rare case of anterior cerebral artery dissection (ACAD) that accompanied fresh cerebral infarction (CI) and subarachnoid hemorrhage (SAH). An initial head CT showed a thin SAH in the interhemispheric cistern and cortical sulcus of the left frontal surface. Subsequent MRI performed 10 min after head CT scan revealed a fresh infarction in the left ACA region. MR-and digital subtraction angiograms demonstrated a dissection in the A2 portion of the left ACA with a leak of contrast media around the left A3 portion, suggesting that the bleeding occurred in a distal portion of the main dilation. Without anti-thrombotic therapy, the patient recovered without complications by blood pressure control and administration of brain-function protection therapies. We found 11 cases similar to the present case in the literature. All cases presented with lower-extremity dominant hemiparesis; however, sudden onset headache was rare. Blood pressure was not well-controlled in 4 out of the 6 known hypertensive cases. Main sites of dissection were located at the A2 portion in all cases except one A3 lesion, and extended to A3 in 2 cases. Conservative therapy led to favorable outcome in 8 cases, while 4 cases underwent surgical interventions for increasing risk of aneurysm rupture after initial observational therapies. Re-bleeding did not occur in any of the 12 cases reviewed. These data suggest that conservative treatment can be considered for an initial management of ACAD with simultaneous CI and SAH. More evidence needs to be accumulated to establish the optimal therapeutic approach for ACAD associated with CI and SAH.

[Multiple cerebral metastasis of a retroperitoneal leiomyosarcoma].

A 61-year-old woman presented with dementia, 7 years after an operation for retroperitoneal leiomyosarcoma. Magnetic resonance imaging (MRI) revealed enhanced masses with perifocal edema in the bilateral frontal regions and a very small mass in the right medial frontal region. The tumors in the bilateral frontal regions were completely removed surgically, and γ-knife radiotherapy was administered for the very small tumor in the right medial frontal region. The histological diagnosis was metastatic leiomyosarcoma. Postoperatively, an MRI showed that the perifocal edemahad decreased, and the symptoms gradually improved. Cerebral metastasis from a retroperitoneal leiomyosarcoma is very uncommon. Ideally, the tumors should be surgically removed because radiotherapy and chemotherapy are apparently ineffective. A combination of complete surgical removal and γ-knife radiotherapy may be effective in prolonging patient survival.

Shrinkage of a vertebral dissecting aneurysm after stent-assisted coil embolization demonstrated by the three-dimensional driven equilibrium sequence. Case report.

A 61-year-old man with a history of cerebellar infarction was transferred to our hospital for the treatment of vertebral artery (VA) stenosis. The VA dissection was treated with endovascular stent placement followed by coil embolization in which shrinkage of the dissecting aneurysm was confirmed by the three-dimensional driven equilibrium (3D DRIVE) sequence. Using 3D DRIVE, the outer contour of the aneurysm was well visualized, free from the influence of the metallic devices. 3D DRIVE may be useful in the follow-up assessment of the vertebrobasilar artery after stent-assisted coil embolization.

Dolichoectasic anterior cerebral artery and hemodynamics.

Dolichoectasia of the intracranial arteries is a rare condition, and the vertebrobasilar system and the internal carotid artery are the most commonly involved structures. We report a rare case of idiopathic dolichoectasia of the anterior cerebral artery in a 22-year-old female. The patient caused an automobile accident and was brought to our hospital in an ambulance. A computed tomography scan and magnetic resonance imaging revealed no fresh lesions, but showed a prominent serpentine structure with calcification and flow void in the region of the interhemispheric fissure, which was suspicious for arteriovenous malformation or arteriovenous fistula. Cerebral angiography demonstrated extensive dilatation of the anterior cerebral artery, but no evidence of arteriovenous malformation or arteriovenous fistula. Single photon emission computed tomography revealed hypoperfusion of the right frontal lobe at rest. Electroencephalography showed no epileptic discharge. The patient's course was uneventful, and she was discharged with no neurologic deficit. There are few reports of hemodynamic changes in cases of dolichoectasia. In the diagnosis of cerebral dolichoectasia, cerebral hemodynamics should be examined carefully in addition to evaluating vascular disease by angiography.

[Hypertensive intracerebral hemorrhage in isolated islands in Nagasaki Prefecture: a remote teleradiology and helicopter transportation system].

Hypertensive intracerebral hemorrhage (HICH) causes significant morbidity and mortality. The time required to transport the patients to a specialized hospital can influence the prognosis. In the isolated islands in Nagasaki prefecture, there is no medical institution which can offer emergent neurosurgical intervention. We reviewed the cases of HICH in this region from January 2006 to September 2010, who were transferred to Nagasaki Medical Center by a helicopter after consultation via teleradiology. Eighty four cases (23%) were transferred via helicopter to our institution from isolated islands. In three of them (4%), re-hemorrhage was demonstrated on computed tomography after helicopter transportation, and one of three had been administered an anti-coagulant agent. Only one case (1%) has deteriorated during helicopter transportation because of acute obstructive hydrocephalus. The outcome at discharge was as follows: modified Rankin Scale (mRS) I: 3 cases (4%), II: 5 cases (6%), III: 3 cases (4%), IV: 30 cases (36%), V: 31 cases (37%), VI: 12 cases (14%), 43 cases (51%) showed poor outcome (mRS V, VI). For medical management in isolated islands, a remote teleradiology system is indispensable to decide a strategy of treatment rapidly, and a helicopter transportation system is very useful in cases requiring emergent neurosurgical intervention, particular in cases of impending cerebral herniation or acute hydrocephalus. However, we may need to expand logistical supporting hospitals or secure other transportation facilities because many of the patients with poor outcome can not return to their home islands.

[Trigeminal neuralgia in an elderly patient associated with a variant of persistent primitive trigeminal artery].

An 86-year-old woman presented with a 10-year history of right paroxysmal facial pain. The trigger zone was the right maxilla. Magnetic resonance (MR) angiography and MR cisternography sourse images showed an aberrant artery originating from the right internal carotid artery anastomosed to the anterior inferior cerebellar artery territory (AICA) of the cerebellum, and it was closed at the root entry zone of trigeminal nerve. The patient underwent microvascular decompression (MVD), and her pain resolved after the operation. Most of the offending vessels that cause trigeminal neuralgia are the superior cerebellar artery (75-80%) and AICA. Although persistent primitive trigeminal artery (PTA) is the most common type of persistent carotid-basilar anastomosis, trigeminal neuralgia associated with PTA or a PTA variant is very rare, and particularly, a PTA variant is an uncommon, anomalous, intracranial vessel. It is necessary to inspect MR imaging scans carefully prior to MVD surgery because they are frequently associated with intracranial aneurysms. During surgery, we must be careful not to injure the perforating arteries from the PTA variant. MVD for trigeminal neuralgia in elderly patients is effective if the patients can have a tolerate general anesthesia. However, when we plan surgery for elderly patients, we must take care that it does not to lead to unexpected complications.

Early intervention to promote oral feeding in patients with intracerebral hemorrhage: a retrospective cohort study.

BACKGROUND: Stroke is a major cause of dysphagia, but little is known about when and how dysphagic patients should be fed and treated after an acute stroke. The purpose of this study is to establish the feasibility, risks and clinical outcomes of early intensive oral care and a new speech and language therapist/nurse led structured policy for oral feeding in patients with an acute intracerebral hemorrhage (ICH). METHODS: A total of 219 patients with spontaneous ICH who were admitted to our institution from 2004 to 2007 were retrospectively analyzed. An early intervention program for oral feeding, which consisted of intensive oral care and early behavioral interventions, was introduced from April 2005 and fully operational by January 2006. Outcomes were compared between an early intervention group of 129 patients recruited after January 2006 and a historical control group of 90 patients recruited between January 2004 and March 2005. A logistic regression technique was used to adjust for baseline differences between the groups. To analyze time to attain oral feeding, the Kaplan-Meier method and Cox proportional hazard model were used. RESULTS: The proportion of patients who could tolerate oral feeding was significantly higher in the early intervention group compared with the control group (112/129 (86.8%) vs. 61/90 (67.8%); odds ratio 3.13, 95% CI, 1.59-6.15; P < 0.001). After adjusting for baseline imbalances, the odds ratio was 4.42 (95% CI, 1.81-10.8; P = 0.001). The incidence of chest infection was lower in the early intervention group compared with the control group (27/129 (20.9%) vs. 32/90 (35.6%); odds ratio 0.48, 95% CI, 0.26-0.88; P = 0.016). A log-rank test found a significant difference in nutritional supplementation-free survival between the two groups (hazard ratio 1.94, 95% CI, 1.46-2.71; P < 0.001). CONCLUSIONS: Our data suggest that the techniques can be used safely and possibly with enough benefit to justify a randomized controlled trial. Further investigation is needed to solve the eating problems that are associated with patients recovering from a severe stroke.

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.

[Pilomyxoid astrocytoma presenting in an elderly patient: a case report].

A 77-year-old man presented with progressive visual disturbance. MR images revealed a mass lesion mainly spreading in the left basal cistern, sylvian fissure and to the left hypothalamic region, with ventricular enlargement. To obtain precise diagnosis of the mass lesion, an open biopsy was performed. The pathological diagnosis was pilomyxoid astrocytoma (PMA). The patient was discharged without adjuvant therapy. A Ventriculoperitoneal shunt procedure was performed afterwards because his hydrocephalic symptoms progressed. PMA is a rare tumor newly added to the glioma section by the WHO classification renewed in 2007, and generally develops in infancy. To our knowledge, there are only four adult cases being reported. In those cases, the symptoms of the disease developed during the second to fourth decade of life. The onset at a more advanced age as in the present case seems to be extremely rare. The treatment strategy described in infant cases is similar to that for pilocytic astrocytoma, but there are only few reports. To establish a treatment protocol for adult patients, further more cases are needed to accumulate knowledge of this rare brain tumor.

Symptomatic syringomyelia associated with a dermoid tumor in the posterior fossa.

A 28-year-old female presented with a dermoid tumor in the posterior fossa associated with symptomatic syringomyelia. Magnetic resonance (MR) imaging revealed cervical syringomyelia and tonsillar herniation concomitant with an intradural posterior fossa tumor which was totally removed. The histological diagnosis was dermoid tumor. Her symptoms subsided and MR imaging demonstrated complete resolution of the syrinx 12 months after tumor removal. Benign congenital intracranial tumor may cause tonsillar herniation resulting in symptomatic cervical syringomyelia. However, both tonsillar herniation and cervical syrinx may clinically and radiologically resolve following removal of the intracranial lesion and posterior fossa decompression.

Coexistence of Chiari 2 malformation and moyamoya syndrome in a 17-year-old girl.

A 17-year-old female with Chiari 2 malformation developed cerebral infarction with angiographically typical bilateral moyamoya vessels manifesting as sudden onset of moderate left hemiparesis. Magnetic resonance imaging revealed multiple infarcts in the right frontal lobe, agenesis of the corpus callosum, upward herniation of the dorsal cerebellum, tectal beak of the midbrain, and downward herniation of the cerebellar vermis. Cerebral angiography demonstrated occlusion of the bilateral internal carotid arteries and basal moyamoya vessels. Single photon emission computed tomography showed significantly reduced regional cerebral blood flow in the right frontoparietal cortex. The cerebral vascular reactivity to acetazolamide was diminished in both cerebral hemispheres. She underwent superficial temporal artery-middle cerebral artery anastomosis combined with encephalo-myo-synangiosis on the right, and on the left 6 months later. Cerebral angiography performed 4 months after the second operation showed good patency of the bypasses and substantial collateral vessels in both cerebral hemispheres. This association may have happened by chance, and a common etiology is uncertain, but a currently undetermined genomic component might have contributed to the disease progression.

Factors affecting rapid growth of unruptured cerebral aneurysms during the acute stage of subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Several unruptured cerebral aneurysms have been reported to grow and rupture. To determine which factors affect the growth of these aneurysms during the acute stage of subarachnoid hemorrhage (SAH), a retrospective review was performed. METHODS: Between January 2000 and January 2003, 130 patients with angiographically proven ruptured cerebral aneurysms were treated at our institution. Of these patients, 32 also had simultaneous unruptured aneurysms, and the total number of the unruptured aneurysms was 40, including two neck remnants which had remained since the past clipping. Seventeen patients had 17 unruptured aneurysms and two neck remnants. The unruptured aneurysms were not treated during the acute stage of SAH but had received a complete short term follow-up. RESULTS: The rapid growth of one unruptured aneurysm and two neck remnants was confirmed by a second angiogram performed on average 40 days after the first angiogram. Several candidate factors responsible for the growth of aneurysm were selected, and the results of a statistical analysis indicate that a systolic blood pressure above 200 mmHg during the acute stage of SAH and vasospasm, confirmed by transcranial Doppler ultrasound (TCD) or neurological examination, and neck remnants, are risk factors that affect the growth. CONCLUSIONS: Short term follow-up angiography is thus important for patients with untreated unruptured cerebral aneurysms after the acute stage of SAH.

Cerebral composite atypical teratoid/rhabdoid tumor and yolk sac tumor in the frontal lobe of an infant. Case report.

A 1-year-old male infant presented with a rare cerebral composite tumor consisting of atypical teratoid/rhabdoid tumor (AT/RT) with epithelial and mesenchymal components and yolk sac tumor (YST) with Schiller-Duval bodies. He was admitted to our medical center with a 2-month history of right hemiparesis. Computed tomography and magnetic resonance imaging revealed a large, intra-axial solid tumor with a cyst in the left frontal lobe. Total resection of the tumor was performed. Histological examination showed two different main growth patterns: solid sheets of undifferentiated polygonal cells and a few rhabdoid cells with rosette structures and rhabdomyoblastic cells; and reticular or papillary structures with occasional Schiller-Duval bodies in a myxoid matrix. The immunohistochemical and electron microscopy findings indicated composite AT/RT and YST. Initial total resection of the tumor was subsequently followed by local recurrence, hydrocephalus, and spinal metastasis. Despite adjuvant chemotherapy, the patient died 9 months after admission. AT/RT is a recently established entity of the central nervous system. The present case of composite AT/RT and YST in the frontal lobe indicates the poor prognosis of such tumors.

Aneurysms of the posterior cerebral artery: retrospective review of surgical treatment.

A series of 10 cases of posterior cerebral artery (PCA) aneurysms were retrospectively reviewed. There were five men and five women aged 38 to 68 years (mean 57.5 years). Seven patients presented with subarachnoid hemorrhage. Two aneurysms were found incidentally during clinical examination for stroke. One aneurysm was associated with moyamoya disease. All aneurysms were saccular. The aneurysms arose from the P1 segment in three patients, the P1/P2 junction in three patients, the P2 segment in three patients, and the P3 segment in one patient. Two patients died before operation and one patient refused surgery. Aneurysmal clipping was performed for seven patients. All aneurysms except the P2 and the P3 aneurysms were treated via the pterional approach. Four patients had excellent outcome, but one patient with a P3 aneurysm developed homonymous hemianopsia due to thrombosis of the parent vessel and another patient with a P2 aneurysm had moderate disability from the initial insult. Coil embolization has been indicated as the first choice of therapy, but PCA aneurysms are good candidates for direct clipping.