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Yasuhiko Ajimi

Publications and source records attributed to Yasuhiko Ajimi.

3 recordsLinked to original sources

Selective reconstructive options for the anterior skull base.

Carcinomas of the ethmoid, frontal, or maxillary sinuses sometimes invade the anterior skull base. It is necessary to perform en-bloc resection for this invasive carcinoma according to the concepts of surgical treatment for head and neck cancer. The anterior skull base consists of two parts, the orbital roof as the lateral portion and the roofs of the frontal sinus, ethmoid sinus, and/or sphenoid sinus as the central portion. Selective reconstructive options for the anterior skull base depend on the size of the defect of the skull base. A dural defect is repaired by a fascia lata or a pericranial flap. After the dura has been tacked up, reconstruction of the anterior skull base is performed simultaneously with augmentation of the defect of extracranial structures. Larger defects that consist of both central and lateral portions with orbitomaxillary structures are reconstructed by a bulky musculocutaneous flap such as a rectus abdominis or latissimus dorsi flap. The bony reconstruction of supraorbital structures is also to be considered esthetically. On the other hand, intraorbital tissues are basically preserved in cases of central defects of the anterior skull base. These defects are reconstructed by a free forearm flap or a local flap such as a de-epithelialized midline forehead flap or a pericranial flap. We have selected and applied these flaps in 37 patients as reconstructive options for the anterior skull base since 1989. Eleven of the 37 patients had larger defects and 26 had central defects. De-epithelialized midline forehead flaps were used in 20 patients and were recognized to be a very useful and reliable reconstructive option for central defects of the anterior skull base.

Child, Preschool↗

Cortical blindness during coil embolization of an unruptured intracranial aneurysm--case report.

A 62-year-old woman suffered transient cortical blindness during coil embolization for a saccular aneurysm in the posterior circulation, with cerebral angiography using non-ionic contrast material. Just before completion of the procedure, the patient showed abrupt onset of restlessness and blindness. At this point 150 ml of contrast material had been injected into the left vertebral artery. Immediate computed tomography showed persistence of contrast medium in the bilateral occipital lobes and part of the left frontal lobe. Repeat angiography showed no evidence of embolism. Single photon emission computed tomography obtained the next day showed decreased perfusion in the bilateral occipital lobes. Magnetic resonance imaging on the third day showed multiple lesions in the bilateral occipital lobes. Her vision was restored gradually. Transient cortical blindness may be associated with osmotic disruption of the blood-brain barrier in the bilateral occipital lobes. Endovascular neurosurgeons must be aware of this rare complication.

Blindness, Cortical↗

Ruptured dissecting aneurysm of the vertebral artery associated with occlusive internal carotid artery dissection--case report.

A 64-year-old male presented with subarachnoid hemorrhage. Angiography showed a dissecting aneurysm of the right vertebral artery (VA), and severe stenosis of the right internal carotid artery (ICA). He was treated conservatively in the early stage. Repeat angiography showed enlargement of the dissecting aneurysm of the VA and partial resolution of the stenosis of the right ICA. Intraaneurysmal coil embolization with proximal coil occlusion was performed following a balloon occlusion test. The postoperative course was uneventful. Based on the neuroradiological findings, the stenotic lesion of the right ICA was considered to be due to dissection. Analysis of serial changes in dissecting lesions in the craniocervical arteries is important for the correct choice of treatment, especially in patients with multi-vessel dissections. The surgical options should be determined on an individual basis.

Aneurysm, Ruptured↗