Biomedical subjects

Kunihiko Umezawa

Publications and source records attributed to Kunihiko Umezawa.

7 recordsLinked to original sources

PubMed2005

[Non-cardiogenic pulmonary edema induced by non-ionic radiographic contrast media during the coil embolization for a ruptured cerebral aneurysm].

We describe a 48(correction of 44) year-old woman, who presents a non-cardiogenic pulmonary edema caused by non-ionic radiographic contrast medium. She suffered from subarachnoid hemorrhage due to dissecting aneurysm of right vertebral artery. Cerebral angiography followed by coil embolization for the aneurysm was performed. During the interventional procedure, saturation of blood oxygen suddenly declined and chest X-ray photography obviously revealed pulmonary edema. At first we dealt with it as neurogenic phenomenon but subsequently interpreted it to non-cardiogenic pulmonary edema induced by radiographic contrast medium, since intra-arterial injection of contrast medium at follow-up angiography led the symptoms into more fulminant status. Intensive care including endotracheal intubation and continuous positive airway pressure ventilation consequently achieved complete remission and the patient discharged without any sequelae. Although low osmolar, non-ionic contrast medium has been regarded as relatively safe, severe reaction such as dyspnea, hypotension and cardiac arrest could emerge at certain intervals. We must perceive the adverse effects of it because the usage of contrast medium will dramatically increase with development of diagnostic radiographical methodology and interventional neurosurgery.

Aortic Dissection↗

PubMed2004

Cavernous angioma presenting as epilepsy 13 years after initial diagnosis.

A 22-year-old man presented with tonic-clonic seizure and was admitted to our hospital. He had suffered from frequent headaches, and had been diagnosed with a brain tumour on MRI 13 years ago. However, neither further examination nor follow-up neuroimaging study have been performed. Computed tomography and magnetic resonance imaging demonstrated an intraaxial tumor with granular calcification in the right frontal lobe, attached to the adjacent dura mater, which was enlarged compared with the lesion on CT 13 years before. The lesion was surgically excised through right frontal craniotomy. Histopathological analysis indicated cavernous angioma. In cavernous angioma in younger children, more aggressive surgical indications than in adults may be favorable both to prevent haemorrhagic complications and to confirm pathologic diagnosis.

Adult↗

PubMed2003

Vertebrobasilar artery dissection presenting with simultaneous subarachnoid hemorrhage and brain stem infarction: case report.

BACKGROUND: Intracranial dissecting aneurysms have been associated with subarachnoid hemorrhage (SAH) or cerebral ischemia. We encountered a patient presenting with simultaneous subarachnoid hemorrhage and brainstem infarction caused by a dissecting aneurysm of the vertebrobasilar artery, which was diagnosed by magnetic resonance imaging (MRI) but did not show abnormal findings on cerebral angiography. CASE DESCRIPTION: A 55-year-old man had sudden onset of headache and left abducens palsy. Computed tomography revealed a subarachnoid hemorrhage localized in the left prepontine cistern and the left cerebellomedullary fissure. Cerebral angiography showed neither a saccular aneurysm nor fusiform dilatation causing the subarachnoid hemorrhage. MRI demonstrated a small infarction in the left dorsal pons, and an intramural hematoma of the left vertebral artery and lower basilar artery. CONCLUSION: This is a rare case of a vertebrobasilar dissecting aneurysm that simultaneously caused both SAH and brain stem infarction. MRI should be performed in the acute phase of SAH of unknown origin to determine the possible coexistence of a dissecting aneurysm, as occurred in this case.

Aortic Dissection↗

PubMed2003

Fatal rupture following intra-aneurysmal embolization for the distal posterior inferior cerebellar artery aneurysm with parent artery preservation.

This 70-year-old female was admitted to our hospital 1 day after a sudden consciousness disturbance. Computed tomography (CT) showed subarachnoid hemorrhage (SAH), and angiogram revealed an irregular-shaped aneurysm at the lateral medullary segment of the left posterior inferior cerebellar artery (PICA). The patient was treated by intra-aneurysmal embolization with Guglielmi detachable coil (GDC) with parent artery preservation. Post-operative angiogram showed obliteration of the aneurysm except for the neck remnant, but she presented with rerupture 19 days after the onset and died 3 days later. Postmortem examination revealed massive hematoma around the aneurysm, which compressed medulla oblongata from behind. Histological assessment showed the 'entry' where the aneurysmal wall lacked internal elastic lamina, providing evidence of dissecting aneurysm. The present case suggests that embolization of distal PICA aneurysm with parent artery preservation should be avoided because radiological evaluation may fail to rule out the possibility of dissection, where the aneurysmal wall is affected not only at the 'entry' but also in the adjacent region.

Aged↗

PubMed2003

Optochiasmal arachnoiditis following cotton wrapping of anterior communicating artery aneurysm treated by surgical removal of granuloma.

We report the case of a 50 year old female who presented with visual disturbance due to optochiasmal arachnoiditis and foreign body granuloma 9 months after cotton wrapping for ruptured anterior communicating artery (AcomA) aneurysm. Magnetic resonance imaging (MRI) revealed enhanced mass lesion around AcomA complex and hyperintense signal on optic chiasm and right optic tract by fluid-attenuated inversion recovery image. Despite the repeated steroid pulse therapy, she deteriorated and MRI showed expansion of the granulomatous lesion over 5 months. Surgical removal of foreign body granuloma resulted in marked improvement of visual disturbance as well as of the MRI findings. We conclude that the use of cotton sheet close to the optic nerve should be avoided, and that surgical removal of the granuloma would be the optimal choice especially for the patient in whom steroid therapy fails to improve clinical symptoms.

Arachnoiditis↗

PubMed2002

A case of calvarial eosinophilic granuloma with rapid expansion and wide skull invasion: immunohistochemical analysis of Ki-67.

A 15-year-old male visited our neurological service with progressive occipitalgia. Computed tomography showed an osteolytic lesion at the occipital cranium, which grew rapidly during a month. Magnetic resonance imaging showed the lesion as low intensity on T1- and high intensity on T2-weighted images. The mass was soft and successfully removed with surrounding cranium. Histological examination revealed an eosinophilic granuloma with wide skull invasion. Immunohistochemical analysis on the specimen disclosed Ki-67 expression with labeling index of 6.2%. Relatively high proliferative activity in the present case indicates that the local replication of Langerhans' cells as well as inflammatory response contributes to the expansion of calvarial eosinophilic granuloma. This is the first report demonstrating the result of Ki-67 expression on calvarial eosinophilic granuloma.

Adolescent↗

PubMed2002

[A case presenting brain abscess with multiple infectious aneurysms].

We report a case presenting a brain abscess with multiple infectious aneurysms. A 59-year-old man was transferred to our hospital suffering from left hemiparesis. MRI demonstrated a huge mass in the right frontal lobe with marked brain edema in the surrounding area. Diffusion-weighted image revealed heterogenous intensity, which is not typical in cases of brain abscess. Surgical removal was planned, and preoperative angiography was performed. Angiography demonstrated aneurysms at the distal branch of both the right middle cerebral artery and the anterior cerebral artery. These aneurysms were surgically resected, and the abscess was totally removed. Postoperative course was uneventful. Left hemiparasis was resolved, and there was no ischemic lesion seen on postoperative MRI. In the treatment of brain abscess, stereotactic aspiration has recently been preferred to removal by craniotomy. We conclude that cerebral angiography might be necessary to evaluate cerebrovascular complications including infectious aneurysms, in cases presenting atypical findings in neuroimaging study.

Aged↗