Formation of a Large Fusiform Aneurysm near a Medullary Infarction Caused by Dissection of the Posterior Inferior Cerebellar Artery.

Infarction of the posterior inferior cerebellar artery (PICA) can lead to ischemic stroke in the lateral medullary oblongata. PICA dissection can also elicit an ischemic event in this region, but its detection on radiological images is difficult because of the small diameter of the vessel. We report a case of Wallenberg syndrome due to PICA dissection in a 48-year-old man, which was difficult to diagnose on first admission. He reported sudden onset of sensory disturbance on the right side of his face, ataxic gait, and headache. Brain magnetic resonance imaging (MRI) revealed a fresh cerebral infarct in the right lateral medulla oblongata. Magnetic resonance angiography (MRA) performed at the time of his admission showed no cerebral vessel abnormalities. An MRI study 18 months after the event revealed a fusiform aneurysm on the lateral medullary segment of the PICA, which was extremely close to the cerebral infarct. We concluded that the infarct was due to PICA dissection because of the sudden onset of symptoms and because the infarcted territory of the occluded penetrating branch of the dissecting aneurysm was consistent with Wallenberg syndrome. The aneurysm was trapped and an occipital artery-PICA bypass was placed. At the latest follow-up, 1 year after the procedure, he had no neurological symptoms. Imaging findings at the time of his first admission indicated that the PICA was intact. However, 18 months later, MRI revealed enlargement of an aneurysm at the site of the dissection. A cerebral infarct with headache may indicate PICA dissection.

Meralgia Paresthetica Caused by Surgery in the Park-Bench Position.

OBJECTIVE: Meralgia paresthetica (MP) is an entrapment neuropathy of the lateral femoral cutaneous nerve (LFCN). We report a rare case of MP after microvascular decompression (MVD) surgery in the park-bench position in a patient with hemifacial spasm. CASE: The patient was a nondiabetic 46-year-old woman (height: 155 cm, weight: 42 kg) who consumed alcohol infrequently. After a first MVD for right hemifacial spasm, the symptom recurred and she underwent a second MVD procedure in the park-bench position, after which hemifacial spasm resolved. However, she reported right anterolateral thigh pain and dysesthesia without motor weakness. The pain was limited to the LFCN area, and a pelvic compression test elicited a positive Tinel-like sign. Our preliminary diagnosis was MP. Because conservative therapy was ineffective, she underwent LFCN block 9 months after the second MVD procedure. Her pain improved dramatically and we made a definitive diagnosis of MP. There has been no recurrence after 30 months of observation, although she reported persistent mild dysesthesia in the LFCN area. CONCLUSION: MP is a rare complication after MVD surgery in the park-bench position. LFCN block can resolve symptoms and hasten diagnosis.

The meningeal branches of the superior cerebellar artery: a surgical observation study.

OBJECT The tentorial branch of the posterior cerebral artery was first identified in a cadaver dissection study. However, the tentorial branch of the superior cerebellar artery (SCA) has not been clearly described in autopsy or normal anatomical studies. In this study, a dural branch of the SCA that was found during the surgical treatment of trigeminal neuralgia is described. METHODS Between April 2011 and March 2014, 70 patients with idiopathic trigeminal neuralgia underwent microvascular decompression. The records of 58 patients were reviewed to investigate the meningeal branch of the SCA. RESULTS The meningeal branch of the SCA was visualized in 15 of the 58 patients (25.9%). In 4 patients, it was necessary to divide this branch in order to achieve decompression of the trigeminal nerve without eliciting postoperative neurological deficits. CONCLUSIONS This is the first identification of the meningeal branch of the SCA in living subjects, and such branches were rather frequently found. Recognition of this branch is important for the management of lesions in the cerebellopontine angle and tentorial lesions, using either an open microsurgical or endovascular method.

Successful treatment of a ruptured flow-related aneurysm in a patient with hemangioblastoma: Case report and review of literature.

BACKGROUND: No cerebral aneurysms on the feeder associated with hemangioblastomas that ruptured before resection have been reported. We report a patient with a ruptured flow-related aneurysm associated with cerebellar hemangioblastoma and a tumor feeder treated simultaneously by a single procedure of embolization using N-butyl cyanoacrylate before tumor removal. CASE DESCRIPTION: A 36-year-old female with a cerebellar tumor was admitted to our institute. Four days later, she suffered a massive subarachnoid hemorrhage mainly in the posterior fossa. Left vertebral angiograms showed an aneurysm on the feeding artery, posterior inferior cerebellar artery. Both the aneurysm and its main feeder were simultaneously treated by a single procedure of embolization using N-butyl cyanoacrylate. Their complete obliteration was confirmed angiographically. Four days after the procedure, we removed the tumor and the embolized aneurysm. The pathological diagnosis was hemangioblastoma and flow-related ruptured aneurysm. CONCLUSION: Cerebral angiography should be performed to rule out vascular abnormalities such as cerebral aneurysms adjacent to the tumor in patients with hemangioblastoma who present with intracranial hemorrhage. We emphasize the usefulness of embolization with N-butyl cyanoacrylate for hemangioblastoma with ruptured feeder aneurysm, by which the aneurysm and the feeder could be simultaneously embolized.

Occlusion of the ascending pharyngeal artery during carotid artery surgery: importance and technique.

AIM: In surgeries involving clamping, opening and repairing the carotid artery such as carotid endarterectomy (CEA) and proximal anastomosis at radial artery (RA) grafting, back-bleeding, often due to insufficient occlusion of the ascending pharyngeal artery (APA), must be avoided. In 96% of cases the APA originates at the dorsal side of the external carotid artery, while in 2% each it arises at the carotid bifurcation or the internal carotid artery. We developed a method to prevent back-bleeding from the APA irrespective of its origin. MATERIAL AND METHODS: For CEA we dissect the internal carotid artery and clamp the APA and the external carotid artery together. For RA grafting we dissect the external carotid artery and if the APA branches directly from this vessel, the APA is clamped directly. RESULTS: We used our new surgical technique in 54 cases (22 CEA and 32 RA grafts) and encountered no major back-bleeding. CONCLUSION: We consider this method to be simple and useful for improving the safety and success of carotid artery surgeries.

Hemothorax after the intravenous administration of tissue plasminogen activator in a patient with acute ischemic stroke and rib fractures.

A 79-year-old man experienced sudden-onset left hemiparesis and disturbance of consciousness. Diffusion-weighted magnetic resonance imaging showed an acute ischemic stroke in the territory of the right middle cerebral artery. He underwent systemic thrombolysis via the intravenous administration of tissue plasminogen activator (t-PA). Chest radiography and computed tomography performed the following day showed severe hemothorax with atelectasis of the left lung and multiple rib fractures; the initial chest radiogram had revealed rib fractures but we did not recognize them at the time. Conservative treatment with the placement of chest tubes was successful, and the patient recovered without further deterioration. Although systemic thrombolysis with t-PA is an accepted treatment for acute cerebral ischemic stroke, posttreatment intracranial hemorrhage has a negative effect on prognosis. Extracranial bleeding is a rare complication, and our search of the literature found no reports of hemothorax after treatment with t-PA in patients with cerebral ischemic stroke. We have reported a rare case of severe hemothorax after systemic thrombolysis with t-PA. This important complication indicates the need to rule out thoracic trauma with radiography and computed tomography of the chest.

Target-controlled infusion technique with indocyanine green videoangiography for radial artery graft.

OBJECT: To understand the relationship between the parent artery and its distal arteries, blood vessels running through the subarachnoid space need to be extensively dissected, which is time-consuming. We examined the efficacy of temporary clipping with the indocyanine green (ICG) technique (target-controlled infusion (TCI) technique), in which the parent artery is occluded using a temporary clip, and ICGV (videoangiography) is performed to clarify the relationship between the distal M4 and proximal M2. METHODS: Thirteen radial artery grafts (RAGs) for internal carotid aneurysm underwent TCI to confirm the relationship between M2 and cortical M4. To monitor the perfusion pressure of the cortical middle cerebral artery, superficial temporal artery (STA) to M4 anastomosis was performed before RA-M2 anastomosis. We performed anastomosis of the recipient of STA- M4 that was distal and downstream of the M2 segment that is the recipient of RA-M2 anastomosis. To select the proper recipient M4 of the STA-M4 anastomosis, the ICGV image range was set sufficiently wide to accommodate the possibility that the distal artery was not the one anticipated. ICGV followed complete occlusion by temporary clipping of the recipient M2. RESULTS: In 2 of the 13 cases, the relationship between the M2 and M4 could not be clarified. CONCLUSIONS: In cases with developed collateral circulation or small perfusion area of the occluded M2, it was difficult to ascertain the relationship by TCI. Nevertheless, TCI was useful in 11 of the 13 cases, suggesting that unnecessary dissection in the subarachnoid space may be reduced using this technique.

Perioperative complications of superficial temporal artery to middle cerebral artery bypass for the treatment of complex middle cerebral artery aneurysms.

OBJECT: Only a few studies have reported the risk of ischemic complications occurring when superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis is performed during surgery for complex MCA aneurysms. SUBJECTS AND METHODS: This is a retrospective study of 10 patients (age 52-73) with MCA aneurysms treated with revascularization surgery. The aneurysms were 10-50mm in size (mean: 21mm). We studied the causes and frequency of ischemic complications by analyzing postoperative magnetic resonance imaging. RESULTS: Postoperative diffusion-imaging confirmed ischemic complications in six of the 10 patients (in two of the five ruptured aneurysms and in four of the five unruptured). The ischemic complications that observed were infarction of the lenticulostriate artery territory in three cases, cortical infarction in two cases, and cerebral infarction that was likely to be due to cerebral vasospasm in one case. In one case, both cortical infarction and infarction of the lenticulostriate artery territory were observed. The Glasgow Outcome Scale (GOS) scores at the time of discharge indicated good recovery (GR) and moderate disability (MD) in seven cases, severe disability (SD) in two cases, and death (D) in one case. CONCLUSIONS: The present study suggests the possibility that STA-MCA anastamosis in surgeries for MCA aneurysms can be performed with comparatively better safety. However, the temporary occlusion time with this surgery is longer than that with a temporary clipping for aneurysmal surgery; thus, we believe that adequate countermeasures are required to prevent ischemic complications.

Ischemic complications after radial artery grafting and aneurysmal trapping for ruptured internal carotid artery anterior wall aneurysm.

OBJECTIVE: Treatment of ruptured internal carotid artery anterior wall (ICAW) aneurysms presents a surgical challenge because limitations and difficulties are encountered with either clipping or endovascular treatment. The present study examined clinical outcomes after aneurysmal trapping followed by radial artery grafting for management of these difficult lesions. METHODS: Radial artery grafting was followed immediately by parent artery occlusion in five sides of five patients with acute ruptured ICAW aneurysm (3 men, 2 women; mean age 55.2 years). All patients underwent postoperative angiography and computerized tomography to assess graft patency and ischemic complications including vasospasm. RESULTS: Of the five patients, only one had a poor outcome. However, temporary ischemic complications due to vasospasm developed in four (80%) of the five patients. Long-term results of radial artery grafting and internal carotid trapping for acute stage ruptured ICAW were satisfactory, but detailed analysis indicated a high risk of ischemic complications. CONCLUSIONS: The long-term result was satisfactory, but there was a high rate of acute stage ischemic complications due to delayed vasospasm and low perfusion from the radial artery graft. Based on these results, the investigators recommend that, in addition to intraoperative anticoagulation therapy, in cases where the cerebral blood flow study in the early postoperative period indicates low cerebral perfusion or in cases with World Federation of Neurological Societies grade III-V, the patients should be placed under the highest level of intensive care to detect ischemic complications.

Dissecting aneurysm of the anterior temporal artery: case report.

A 65-year-old woman presented a rare dissecting aneurysm of the anterior temporal artery (ATA) manifesting as headache. Computed tomography and magnetic resonance imaging revealed a mixed-density mass in the horizontal segment of the middle cerebral artery. Emergent angiography demonstrated aneurysmal dilatation and a thrombosed mass in the sylvian fissure. Infectious aneurysm was excluded. She underwent emergent surgery to reduce the risk of repeated infarction and hemorrhage. The distal side of the ATA manifested occlusive changes suggestive of arterial dissection. The proximal side of the ATA was ligated and the lesion was excised. Histological examination confirmed that the aneurysmal dilatation was attributable to arterial dissection due to disruption of the internal elastic lamina. Distal dissecting aneurysms may occur in the absence of infectious disease. We recommend that ruptured distal dissecting aneurysms be treated surgically in the acute stage immediately after detection.

Radial artery grafts for symptomatic cavernous carotid aneurysms in elderly patients.

BACKGROUND: Radial artery grafts (RAG) have been used in the treatment of complex vascular lesions, but not for symptomatic cavernous carotid aneurysms in elderly patients. AIM: To investigate the safety, usefulness, and perioperative complications of RAGs for symptomatic cavernous carotid aneurysms in elderly patients. MATERIAL AND METHODS: Of the 74 consecutive patients, in whom RAGs were used, we retrospectively investigated the postoperative outcomes and complications in eight elderly patients aged over 70 years with symptomatic internal carotid artery aneurysms in cavernous sinus. RESULTS: Postoperative complications included one case of cerebral infarction, one case of symptomatic seizures, and one case of delayed cranial nerve palsy. OUTCOME: Seven patients had an mRS score of 0, and one patient had a score of 2. Postoperatively there was improvement in cranial nerve palsy in seven patients and the patients who had symptoms for one year and eight months had residual deficits. Although it cannot be stated that the frequency of perioperative complications was low, the final outcomes were favorable. CONCLUSION: Even in carotid disease that is difficult to treat among the elderly, RAG would appear to be a useful and safe treatment.

Cerebral artery restenosis following transluminal balloon angioplasty for vasospasm after subarachnoid hemorrhage.

BACKGROUND: Although percutaneous transluminal angioplasty (PTA) is a widely used less invasive method to treat coronary artery stenosis, 10% of treated patients experience restenosis. Restenosis also occurs in approximately 5% of patients subjected to carotid artery stenting. Animal and human data suggested that restenosis is a response to injury incurred during PTA. As PTA has come into wide use to manage symptomatic cerebral vasospasm after subarachnoid hemorrhage (SAH) we studied the incidence of restenosis after PTA for cerebral vasospasm. METHODS: Our study population consisted of 32 patients who had undergone PTA. They were followed by cerebral or 3DCT angiography or MRA for 6 126 months post-PTA (mean 48.65 months) to diagnose restenosis of the cerebral artery. We compared the size of the cerebral artery on the PTA and the contralateral side. RESULTS: All 32 patients underwent successful PTA of 38 vascular territories and all manifested angiographic improvement of vasospasm. None suffered restenosis during the follow up period. CONCLUSION: PTA resulted in a significant improvement in the vessel diameter in patients with vasospasm after SAH and they did not suffer restenosis in the course of prolonged follow-up.

Dissecting posterior inferior cerebellar artery aneurysm presenting with subarachnoid hemorrhage right after anticoagulant and antiplatelet therapy against ischemic event.

BACKGROUND: Dissecting aneurysms with initial ischemic manifestations may present with subsequent subarachnoid hemorrhage (SAH), and their treatment is controversial. This is a case report that illustrates the dilemma when dealing with an immediate post-SAH period dissecting posterior inferior cerebellar artery (PICA) aneurysm initially presenting with an ischemic event. METHODS: We present a 57-year-old man with a dissecting PICA aneurysm who had SAH right after anticoagulant and antiplatelet therapy for cerebral infarction. The aneurysm was not detected by magnetic resonance angiography performed at the time of admission. RESULTS: On admission, he was treated with both anticoagulant and antiplatelet therapy. After the SAH episode, he underwent emergent resection of the dissecting aneurysm and left OA-PICA anastomosis. CONCLUSION: If hemorrhagic transformation occurs at the site of an ischemic dissecting aneurysm, surgical or endovascular intervention should be considered immediately. Although the optimal treatment of dissecting aneurysms with ischemic onset remains controversial, anticoagulant and antiplatelet therapy should not be rejected out of hand.

Expression of GATA-2 in human pituitary adenomas.

Transcription factor GATA-2 contains two copies of a highly conserved zinc finger domain and plays unique roles at an early stage of hematopoietic differentiation. In the mouse pituitary gland, Pit-1-GATA-2 protein-protein interaction has been shown to lead to gene-specific actions to obtain cell-specific roles. In this study, we investigated the expression of GATA-2 and Pit-1 in human pituitary adenomas using reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical techniques. By immunohistochemical analysis, GATA-2 was detected in all of the gonadotropin-subunit (Gn-su)-positive adenomas (n = 8) and in four of five thyroid-stimulating hormone (TSH)-secreting adenomas, but its incidence was low in the other types of adenomas. Pit-1 protein was detected in 4 of 5 TSH-secreting adenomas and in 10 of 10 growth hormone (GH)-secreting adenomas. By RT-PCR analysis, GATA-2 was detected in all Gn-su-positive adenomas and TSH-secreting adenomas, and Pit-1 was detected in all TSH-secreting adenomas and GH-secreting adenomas. These results suggested that GATA-2 contributes to the functional expression and the differentiation of Gn-su-positive adenomas and the TSH-secreting adenomas and that the interaction between GATA-2 and Pit-1 can lead to gene-specific action and differentiation of TSH-secreting adenomas. It is further speculated that GATA-2 and transcriptional interaction with Pit-1 play roles in the functional differentiation of specific pituitary adenomas.