Albert L. Rhoton Jr., Shigeaki Kobayashi and W. Henry Hollinshead
Kenichiro Sugita, Shigeaki Kobayashi, Akira Shintani and Naomi Mutsuga
✓ The authors report microsurgical treatment in 32 cases of basilar artery aneurysms, operated on with good results in 28 cases, fair results in one, and poor results in one; there were two deaths. Twenty-nine patients (91%) were able to return to social activities. Characteristics of the surgical techniques include 1) taking a transsylvian route; 2) retracting the M1 portion of the middle cerebral artery (occasionally the C1 portion of the internal carotid) medially with tapered brain retractors; and 3) approaching the aneurysm through and between perforators arising from the posterior cerebral artery in cases of high-placed basilar bifurcation. With regard to instrument improvements, tapered brain retractors, a multipurpose head frame, and bayonet clips (Sugita design) proved very helpful.
Kenichiro Sugita, Shigeaki Kobayashi, Toshiki Takemae, Koichi Matsuo and Akira Yokoo
✓ A new technique of direct retraction of an aneurysm or major arteries using tapered brain retractors is introduced. The system requires three separate instruments: 1) a tapered brain retractor, 2) a flexible self-retaining retractor of light weight, and 3) a multipurpose head frame.
Koichi Matsuo, Shigeaki Kobayashi and Kenichiro Sugita
✓ A case of bitemporal hemianopsia in a 68-year-old woman is reported. Surgical exploration revealed bilateral compression of the optic nerves by the arteriosclerotic internal carotid arteries. Microsurgical decompression with unroofing of the optic canals resulted in prompt recovery of the visual fields.
Kenichiro Sugita, Shigeaki Kobayashi, Toshiki Inoue and Tatsuo Banno
✓ New angled fenestrated clips are introduced for surgery of certain difficult aneurysms. Their usefulness was proven in two cases of fusiform vertebral artery aneurysms. The aneurysms were obliterated, new parent arteries were reconstructed, and the inclusion of adjacent vital nerves and vessels in the clips was avoided. Technical problems associated with the application of these clips are discussed.
Related and unrelated to grade of patient, type of aneurysm, and timing of surgery
Thoralf M. Sundt Jr., Shigeaki Kobayashi, Nicolee C. Fode and Jack P. Whisnant
✓ Data from 722 consecutive cases with intracranial aneurysms were stored in a computer and later retrieved for analysis. Results and complications (including preoperative death and morbidity) of the surgical management of these patients were correlated with the Botterell grade of the patient in individuals with a recent subarachnoid hemorrhage (SAH), with the type of aneurysm, and with the timing of the surgical procedure. Patients with no SAH within 30 days prior to hospital admission were classified as “no SAH.” Approximately 30% of all patients had sustained more than one hemorrhage. Death and morbidity rates prior to surgery in good-grade patients with a recent SAH exceeded the risk of surgery itself. Rebleeding was the primary cause for death and morbidity in Grade 1 patients: 3% of Grade 1 patients died from a recurrent hemorrhage and 7% deteriorated to a lower grade. Deterioration from ischemia produced by vasospasm related or unrelated to rebleeding exceeded the risks of rebleeding in Grade 2 patients. There was an operative morbidity of 2% and mortality of 2% in patients who were classified as Grade 1 at the time of surgery, but an overall management morbidity of 3% and mortality of 6% in patients who were in Grade 1 at the time of hospital admission. Early surgery in Grade 1 patients was not associated with an increased incidence of delayed ischemia postoperatively. In Grade 2 patients, the operative morbidity and mortality was 7% and 4%, respectively, and the management morbidity and mortality 16% and 11%, respectively. Early surgery in this group was associated with a high frequency of postoperative delayed ischemia (particularly in patients with more than one SAH). Epsilon-aminocaproic acid appeared to protect against a rebleed, but was associated with a higher incidence of postoperative pulmonary emboli. Intraoperative complications were related both to the size of the aneurysm and to its location. Repair of multiple aneurysms did not adversely affect the result. The surgical approach, the importance of using a self-retaining brain retractor, and the technical complications in these cases are discussed.
Kenichiro Sugita, Shigeaki Kobayashi, Kazuhiko Kyoshima and Fukuo Nakagawa
✓ Twenty-four different kinds of fenestrated clips are introduced for the obliteration of unusual aneurysms. The clips were used for eight aneurysms of the internal carotid artery and 10 aneurysms of the vertebral artery. All but one of the aneurysms were successfully obliterated. Recommendations are made concerning the actual use of the clips.
Akira Yokoo, Kenichiro Sugita, Shigeaki Kobayashi and Koichi Matsuo
✓ A new hemostatic method has been devised that uses a metal shield for treating accidentally injured major cerebral arteries. The metal shield is made of stainless steel, and has a small plate on its outer surface that allows it to be held in a regular aneurysm clip holder. Three different sizes of shield are available. The metal shield is applied to an injured artery with Oxycel and Biobond and held for a few minutes. Bleeding stops instantaneously. This is a simple and effective hemostatic method for an injured artery of small size. Experimental results and clinical application of this method are described.
Kenichiro Sugita, Shigeaki Kobayashi and Akiro Yokoo
✓ The authors describe a method for preserving large bridging veins during neurosurgical procedures by stripping them from the cortex. This technique was used in 81 procedures involving a subtemporal, interhemispheric, infratentorial supracerebellar, and transsylvian approach. Although a small amount of the cortex was often sacrificed, preservation of the vein was easy, and postoperative morbidity was minimized.
Kenichiro Sugita and Shigeaki Kobayashi
✓ Microsurgical removal of large acoustic neurinomas, more than 3 cm in diameter, has been performed by the lateral suboccipital transmeatal approach with the patient in the lateral position in 68 cases in the past 5 years. Sixty-two patients (91%) returned to their former occupations and two died: one in the immediate postoperative period and the other 16 months later. The postoperative follow-up examination showed satisfactory facial nerve function in 70% of the patients. Hearing was preserved in six of 14 patients who had preoperatively retained their auditory function. The authors emphasize the usefulness of bipolar forceps for intraoperative stimulation of the facial nerve and for facial muscle monitoring. The value of the four-pronged hook and the multipurpose head-frame in this procedure is also discussed.