Surgical Treatment of Traumatic Intracranial Aneurysms: Experiences at a Single Center over 30 Years.

OBJECTIVE: Traumatic intracranial aneurysm (tIA) is rare and is associated with high rates of morbidity and mortality. We describe our experiences with tIA at our institution. METHODS: We retrospectively reviewed records from patients who underwent treatment for tIA between January 1986 and December 2015. RESULTS: Data from 5532 patients with cerebral aneurysms between January 1986 and December 2015 were reviewed. Of these, 13 cases (0.23%) were tIA. Most occurred after blunt brain trauma (12/13; 92%). The most common location was the distal anterior cerebral artery (7/13; 53%) followed by the internal carotid artery (5/13; 38%). One patient had a tIA in the distal middle cerebral artery. Delayed intracerebral hemorrhage was the major presentation at the time of aneurysmal rupture (70%). Most patients underwent surgical treatment (10/12; 83.3%), which included clipping (5/10), trapping (3/10), aneurysmal excision and bypass (1/10), and aneurysmal excision and coagulation (1/10). In 2 cases, tIA located in the internal carotid artery was treated with coil embolization and detachable balloon occlusion, respectively. Most patients had good recovery (5/12; 41.7%); 3 patients and 1 patient had moderate and severe disability, respectively; 1 patient was in a vegetative state; and 2 patients died. CONCLUSIONS: tIA is an uncommon complication of head trauma. tIA should be considered when unexpected new symptoms develop in patients with head trauma. Early diagnosis and prompt treatment could help to improve final clinical outcomes.

Correct Plane of the Sylvian Vein Dissection for Middle Cerebral Artery Aneurysm Using Indocyanine Green Videoangiography.

BACKGROUND: Preservation of the superficial Sylvian veins (SSVs) is essential to prevent neurologic deficits during Sylvian dissection. We describe an appropriate surgical approach for unruptured middle cerebral artery (MCA) aneurysms to preserve these veins by using indocyanine green videoangiography (ICG-VA). METHODS: Between August 2014 and August 2015, we performed microsurgical clipping for 37 unruptured MCA aneurysms in 36 patients. We classified all of the cases into 3 types according to the location between the Sylvian fissure and the SSV. We defined 3 surgical approaches (frontosylvian, intersylvian, and temporo-sylvian) based on the SSV and investigated the proper surgical approach according to the type of case. RESULTS: In our study, most SSVs were located above the Sylvian fissure (fissure type, 64.9%). The SSV was located on the temporal lobe in 10 cases (temporal type) and on the frontal lobe in 3 cases (frontal type). The frontosylvian approach (splitting between the SSV and frontal lobe) was performed in all of the patients with temporal type; the temporo-sylvian approach (splitting between the SSV and temporal lobe) was performed in all of the patients with frontal type and single SSV of fissure type. The intersylvian approach (splitting between the frontal and temporal SSV, or among multiple SSVs) was successfully performed in the patients with double or multiple SSVs of fissure type. No venous complications occurred that were related to the surgical approach. CONCLUSIONS: Correct dissection strategy using intraoperative ICG-VA is greatly useful to define the optimal surgical approach without vein injury.

Brain stem herniation secondary to cerebrospinal fluid drainage in ruptured aneurysm surgery: a case report.

BACKGROUND: A lumbar drainage catheter is frequently placed intra-operatively to decrease fluid pressure on the brain in aneurysmal subarachnoid cases. In rare cases, this catheter placement can lead to intracranial hypotension, resulting in brain stem herniation termed "brain sag" and it can lead to neurological injury and may prove to be fatal. We present our patient with brain sag secondary to intraoperative lumbar drainage. CASE DESCRIPTION: A 56-year-old woman was admitted with a sudden onset of severe headache. A computed tomography (CT) scan revealed diffuse subarachnoid hemorrhage with ruptured anterior communicating artery aneurysm. After general anesthesia, a lumbar drainage catheter was placed intra-operatively to reduce pressure on the brain and 50 cc of CSF was removed during a 5-h period. Three to five days after operation, her neurologic symptoms became worse with an altered mental state and pupillary asymmetry. CT and magnetic resonance imaging (MRI) showed slit lateral ventricles, effacement of the cisterns and an elongated brain stem. After placing the patient in the Trendelenburg position, the patient rapidly recovered to her baseline neurologic state. DISCUSSION: Typical complications of subarachnoid hemorrhage such as vasospasm or hydrocephalus also manifest as neurological deterioration, but their treatments differ greatly from those for brain sag. Thusly, it is important to distinguish between causes. Treatments such as lumbar or extra-ventricular drainage, induced hypertension or administration of mannitol must be stopped once brain sag is suspected. Also, care should be taken for typical imaging features of brain sag on CT or MRI scan. For brain sag, placing the patient in the Trendelenburg position can improve neurological status in a rapid fashion. CONCLUSIONS: Brain sag is a rare but serious condition and can be fatal if not rapidly diagnosed and treated. We therefore recommend including brain sag in the differential diagnosis, along with vasospasm, hydrocephalus or cerebral edema as part of possible complications following subarachnoid hemorrhage treatment. We hope our clinical and imaging data from this case study contribute to the correct diagnosis of brain sag, as its early detection is important.

Rupture of distal anterior cerebral artery aneurysm presenting only subdural hemorrhage without subarachnoid hemorrhage: a case report.

Intracranial aneurysm rupture usually manifests with subarachnoid hemorrhage, often combined with intracerebral hemorrhage with intraventricular hemorrhage extension. In rare cases, however, these aneurysms present only as subdural hematomas. Recently, we treated a 48-years-old female patient who presented only with subdural hematoma. Interestingly, she did not have a history of trauma. Computed tomography angiography and digital subtraction angiography revealed a 5 × 3 mm sized aneurysm at the A3-A4 junction of the left anterior cerebral artery. On admission, emergency operation (clipping and hematoma evacuation) was performed to protect against re-bleeding. Along with postoperative intensive care, the patient returned to normal daily life with only a mild headache. Given that patients may present with atraumatic acute subdural hematoma, the clinician must bear in mind the possibility of intracranial vascular pathology and obtain angiographic scans to evaluate for any underlying conditions to prevent patient deaths.

Reconstructive Endovascular Treatment of an Intracranial Infectious Aneurysm in Bacterial Meningitis: A Case Report and Review of Literature.

BACKGROUND: Intracranial infectious aneurysms (IAs) are rare cerebrovascular lesions that represent only 1%-6% of all intracranial aneurysms. IAs are rare cerebrovascular lesions and pose a significant therapeutic challenge because of their angiographic and pathophysiologic features. We describe a patient with an intracranial IA treated by the use of reconstructive endovascular methods using a balloon-expandable covered stent and discuss the pathophysiologic characteristics of IA based on serial brain imaging findings. CASE DESCRIPTION: A 21-year-old man was admitted to our emergency department with headache and vomiting. Neurologic examination, hematologic workup, and cerebrospinal fluid examination confirmed a diagnosis of bacterial meningitis. Initial brain magnetic resonance angiography revealed no significant stenosis lesions or aneurysm. After 4 weeks of antibiotic treatment, follow-up brain magnetic resonance imaging revealed an 8-mm sized aneurysm on the petrous portion of the right internal carotid artery, and 3 months later, follow-up brain magnetic resonance angiography revealed that the aneurysm had increased in size from 8 to 15 mm. Conventional 4-vessel angiography confirmed the presence of a pseudoaneurysm. Endovascular treatment was then planned via the use of a balloon-expandable covered stent. Postoperatively, the patient was discharged without specific neurologic deficit. CONCLUSIONS: IAs are rare cerebrovascular lesions and pose a significant therapeutic challenge because of their angiographic and pathophysiologic features. Although endovascular treatment is not performed routinely for infectious aneurysms, the covered stent may represent a safe and effective treatment that achieves complete endoluminal reconstruction of the damaged vessel wall.

Specific and helpful intraoperative indocyanine green videoangiography finding of blood blister-like aneurysm of internal carotid artery.

BACKGROUND: Blood blister-like aneurysms (BBAs) account for 0.5-2.0 % of ruptured intracranial aneurysms. Because of their rarity, the natural history and pathophysiology of such aneurysms are not fully understood. We present two patients with BBAs treated with Bemsheets-covered clipping and discuss their pathophysiological characteristics, through the intraoperative and specific indocyanine green (ICG) video angiography (VA) findings. CASE REPORT: A 34-year-old male and a 53-year-old female were admitted to our emergency room with suddenly reduced levels of consciousness. Brain imaging studies demonstrated a blood blister-like aneurysm of the supraclinoid segment of the right ICA. Craniotomy and an attempt of surgical clipping were performed. ICG-VA showed the filling defect of dye in aneurysm in the operative field. The BBAs were clipped after being covered by Bemsheets (Kawamoto Corporation, Osaka, Japan) and then confirmed by the ICG-VA. Postoperatively, both patients showed transient neurological deficit due to vasospasms and recovered to their normal statuses within a few months after their respective operations. CONCLUSIONS: ICG-VA showed the filling defect of dye in BBAs, which supported that BBAs have been a pseudoaneurysm. In addition, although not routinely recommended in the treatment of BBAs, we believe that Bemsheet-covered clipping is a safe and effective treatment option for BBAs.

Differences in the clinical courses of pediatric and adult pilocytic astrocytomas with progression: a single-institution study.

PURPOSE: Pilocytic astrocytoma (PA) is a World Health Organization grade I neoplasm that generally follows a benign course. However, in some patients, PA exhibits an aggressive clinical course. Here, we examined the clinical course of pediatric and adult PAs with progression at a single institution. METHODS: Between 1995 and 2013, 39 patients with PA were treated. Nineteen were pediatric patients (mean age, 12 years; range, 1-17 years) with a male-to-female patient ratio of 10:9, while 20 were adults (mean age, 36.4 years; range, 19-65 years) with a male-to-female ratio of 9:11. We analyzed and compared tumor location, extent of tumor resection, adjuvant treatment, and clinical course in all patients. RESULTS: In the 19 pediatric patients, tumors were located in the cerebellar vermis, cerebellar hemisphere, optic pathways plus hypothalamus, hypothalamus, brainstem, and the temporal lobe in 6 (31.6%), 5 (26.3%), 3 (15.8%), 2 (10.5%), and 2 (10.5%) patients and 1 (5.3%) patient, respectively. The mass was totally, subtotally, or partially resected in 11 (57.9%), 2 (10.5%), and 4 (21.1%) patients, respectively; biopsies were performed in 2 (10.5%) patients. Immediate postoperative adjuvant treatment was carried out in 6 patients. Tumor progression was detected in 3 patients at 3.0, 4.6, and 5.2 years after treatment, respectively, without significant symptoms. In the 20 adult patients, tumors were located in the cerebellar hemisphere, cerebellar vermis, hypothalamus, brainstem, cerebral hemisphere, and lateral ventricle in 5 (25%), 4 (20%), 3 (15%), 3 (15%), 3 (15%), and 2 (10%) patients, respectively. The mass was totally, subtotally, or partially resected in 11 (55%) and 6 (30%) patients and 1 (5%) patient, respectively; biopsies were performed in 2 patients. Immediate adjuvant treatment was carried out in 2 patients. Progression was detected in 3 patients at 0.3, 0.9, and 2.5 years after treatment, respectively, with progressive neurologic symptoms. There was one case of disease-related mortality during follow-up among the adult patients. CONCLUSION: Most of the PA cases evaluated in this study were benign. However, tumor progression in adult PAs followed a more aggressive clinical course than those in pediatric PAs.

Pediatric brainstem abscess with hemorrhage mimicking diffuse intrinsic pontine glioma: a case report.

PURPOSE: We report a rare case of brainstem abscess with hemorrhage mimicking diffuse intrinsic pontine glioma (DIPG). METHODS: A 7-month-old baby girl presented with lethargy and poor oral feeding. She had the mild fever for 1 month. Brain computed tomography revealed the hypodense lesion in the pons. Brain magnetic resonance images (MRI) showed around 1.4-cm-sized rim-enhanced mass with perilesional edema and internal hemorrhage in the pons. The cerebral blood volume was increased in the rim-enhanced area. The provisional diagnosis was DIPG, but the mass did not show the expansile mass with encasement of the basilar artery on the ventral pons. RESULTS: The biopsy was done via the floor of the fourth ventricle, and the pathologic findings showed the many inflammatory cells and CD68-immunopositive macrophage which were compatible with abscess. The antibiotics with ceftriaxone and metronidazole were administrated for 11 weeks, and the follow-up MRI showed the slightly small enhanced lesion without central necrotic area. Three years later, follow-up MRI revealed the encephalomalacic change and atrophy of the pons. She had the stable neurologic deficit of left facial palsy and right hemiparesis. CONCLUSION: The biopsy could be necessary for pontine lesions without typical radiologic findings of DIPG.

Traumatic Dural Venous Sinus Injury.

OBJECTIVE: The importance of traumatic dural venous sinus injury lies in the probability of massive blood loss at the time of trauma or emergency operation resulting in a high mortality rate during the perioperative period. We considered the appropriate methods of treatment that are most essential in the overall management of traumatic dural venous sinus injuries. METHODS: We conducted a retrospective review of all cases involving patients with dural venous sinus injury who presented to our hospital between January 1999 and December 2014. RESULTS: Between January 1999 and December 2014, 20 patients with a dural venous sinus injury out of the 1,200 patients with severe head injuries who had been operated upon in our clinic were reviewed retrospectively. There were 17 male and 3 female patients. In 11 out of the 13 patients with a linear skull fracture crossing the dural venous sinus, massive blood loss from the injured sinus wall could be controlled by simple digital pressure using Gelfoam. All 5 patients with a linear skull fracture parallel to the sinus over the venous sinus developed massive sinus bleeding that could not be controlled by simple digital pressure. CONCLUSION: When there is a linear skull fracture parallel to the sinus over the dural venous sinus or a depressed skull fracture penetrating the sinus, the surgeon should be prepared for the possibility of potentially fatal venous sinus injury, even in the absence of a hematoma.

Rapid clinical course of cerebral metastatic angiosarcoma from the heart.

We report here one case of rapid and aggressive course of cerebral metastatic angiosarcoma from the heart. A 36-year-old man presented with 10-days history of headache. Magnetic resonance imaging demonstrated subacute hemorrhage with a small region of enhancement in right parietal region and the pathological diagnosis was angiosarcoma. Transthoracic echocardiography demonstrated 3.2×3 cm sized mass on right atrial wall. Newly developed lesion was reoperated, three and four weeks later respectively, and whole brain radiotherapy of total 30 Gy was done. With the interval of two months, gamma knife surgery was done for new lesions two times, which were well controlled. Newly developed lesions rapidly happened even in the adjuvant treatment. He died 9 months after the diagnosis because of the aggravation of primary cancer. The cerebral metastatic angiosarcoma from the heart showed the rapid aggressive behavior and the closed follow-up could be needed for the adjuvant treatment.

Tailored surgical approaches for benign craniovertebral junction tumors.

OBJECTIVE: We report our surgical experience in the treatment of 16 consecutive patients with benign craniovertebral junction (CVJ) tumor, observed from 2003 to 2008 at our department. METHODS: We had treated 6 foramen magnum meningiomas, 6 cervicomedullary hemangioblastomas, 1 accessory nerve schwannoma, 1 hypoglossal nerve schwannoma, 1 C2 root schwannoma, and 1 cavernous hemangioma. Clinical results were evaluated by Karnofsky Performance Scale (KPS) and all patients underwent preoperative neuroradiological evaluation with computed tomography (CT) and magnetic resonance image (MRI). Angiography was performed in 15 patients and preoperative embolization was done in 2 patients. RESULTS: Five far-lateral, 1 supracondylar and 10 midline suboccipital approaches were performed. Gross total removal was achieved in 15 cases (94%) and subtotal removal in 1 patient (6%). None of the patients required occipitocervical fusion. Radiological follow-up showed no recurrence in cases totally removed. Postoperative decrease of KPS scores was recorded in only 1 patient. The treatment of cervicomedullary solid hemangioblastoma presented particular issues : by preoperative embolization, we removed tumor totally without an excessive bleeding or brainstem injury. In one of foramen magnum meningioma, we carried out subtotal removal due to hard tumor consistency and encasement of neurovascular structures. CONCLUSION: : The choice of surgical approaches and the extent of bone resection should be defined according to the location and size of individual tumors. Moreover, we emphasize that preoperative neuroradiological evaluations on presumptive tumor type could be helpful to the surgeon in tailoring the technique and providing the required exposure for different lesions, without unnecessary surgical steps.

Excitatory actions of GABA in the suprachiasmatic nucleus.

Neurons in the suprachiasmatic nucleus (SCN) are responsible for the generation of circadian oscillations, and understanding how these neurons communicate to form a functional circuit is a critical issue. The neurotransmitter GABA and its receptors are widely expressed in the SCN where they mediate cell-to-cell communication. Previous studies have raised the possibility that GABA can function as an excitatory transmitter in adult SCN neurons during the day, but this work is controversial. In the present study, we first tested the hypothesis that GABA can evoke excitatory responses during certain phases of the daily cycle by broadly sampling how SCN neurons respond to GABA using extracellular single-unit recording and gramicidin-perforated-patch recording techniques. We found that, although GABA inhibits most SCN neurons, some level of GABA-mediated excitation was present in both dorsal and ventral regions of the SCN, regardless of the time of day. These GABA-evoked excitatory responses were most common during the night in the dorsal SCN region. The Na(+)-K(+)-2Cl(-) cotransporter (NKCC) inhibitor, bumetanide, prevented these excitatory responses. In individual neurons, the application of bumetanide was sufficient to change GABA-evoked excitation to inhibition. Calcium-imaging experiments also indicated that GABA-elicited calcium transients in SCN cells are highly dependent on the NKCC isoform 1 (NKCC1). Finally, Western blot analysis indicated that NKCC1 expression in the dorsal SCN is higher in the night. Together, this work indicates that GABA can play an excitatory role in communication between adult SCN neurons and that this excitation is critically dependent on NKCC1.