Hideaki Nukui

Postoperative intracerebral hemorrhages: A survey of computed tomographic findings after 1074 intracranial operations

We surveyed computed tomographic findings after 1074 intracranial operations to determine the incidence and etiology of postoperative intracerebral hemorrhages. Medium or large hemorrhages occurred after 42 operations (3.9%). Larger hemorrhages, hemorrhages in the suprasellar region, and hemorrhages associated with other types often preceded a poor outcome. Major etiologies underlying postoperative intracerebral hemorrhages were uncontrolled bleeding from a blind area, difficult dissection of a tumor from the brain, retraction injury, vessel injury from a needle, bleeding from a residual tumor, local hemodynamic changes after removal of a tumor, premature rupture of an aneurysm, and hypertensive putaminal hemorrhage. Hypertension during recovery from anesthesia was another important factor.

Postoperative Extradural Hematomas: Computed Tomographic Survey of 1105 Intracranial Operations

We reviewed the computed tomographic findings after 1055 intracranial operations to determine the incidence of postoperative extradural hematomas. There were 11 medium and 5 large hematomas after 1055 operations (1.0%). Ten of the 16 hematomas were operated upon (10/1055, 0.9%). Four of the 10 hematomas were seen after 278 brain tumor removals (1.4%), another four after 190 aneurysmal operations (2.1%), one after 14 intracerebral hematoma removals (7.1%), and the last one after 251 ventricular shunting or drainage procedures (0.4%). In 4 of the 10 operated hematomas, sites were regional, in five sites were adjacent, and in one the site was distant. All of the five adjacent hematomas extended downward from a lower rim of the operative locus. Causes were analyzed in the three types of the hematomas. In case of the regional hematomas, the causes were incomplete hemostasis of the dura mater or the bone in all four patients, nonperformance of central stay sutures in three, systemic hypertension in one, and hypofibrinogenemia in one. In the adjacent hematomas, we could find dural separation at an edge of craniotomy in all five patients, abrupt collapse of the brain in all, ventricular dilatation in two, and systemic hypertension during immediate postoperative period in two. In one distant hematoma, ventricular dilatation and ventricular shunting procedure were themselves thought to be the causal factors.

Postoperative subdural fluid collections in neurosurgery

After introduction of computed tomography (CT) scanning, subdural fluid collections (SFCs) have been more frequently detected. We encountered 1013 operated cases in which CT scans were performed at an early postoperative stage. Postoperative SFC occurred in 165 of the 1013 operated cases (17%). The incidence of SFC was highest in aneurysm surgery (47%), followed by neurovascular decompression (27%) and brain tumor surgery (22%). In aneurysm surgery, preoperative ventricular dilatation seemed to promote the occurrence of SFC. In tumor surgery, SFC occurred more frequently when the tumor existed in the sellar region. The SFCs decreased or disappeared in most cases on sequential CT scans, but increased in 27 cases. In the latter, maximum thickness of the SFC was seen between 20 and 30 postoperative days. Nineteen of the 27 cases had preoperative ventricular dilatation. Operation for SFC was performed in four cases with clinical symptoms and signs. Three of 169 cases developed into chronic subdural hematomas.

Psychiatric symptoms in ruptured anterior communicating aneurysms: social prognosis

Pre‐ and postoperative psychiatric symptoms were compared in 85 patients with anterior communicating aneurysms and 73 of these cases were followed up to determine the long‐term results. Psychiatric symptoms of varying severity were present preoperatively in 61 % of the cases, which decreased to 34 % after surgery. Use of the microsurgery microscope resulted in a no change: aggravation:mortality ratio of 27:5:0, as compared with 33:204 when the microscope was not used.

Immediate postoperative seizures: incidence and computed tomographic findings

Convulsive seizures within 48 hours after intracranial operations using a craniotomy were reviewed. Incidence was 8.9% (44 of 493 operations): 13.5% of brain tumor operations and 3.8% of aneurysmal operations. We demonstrated that preoperative seizures, sites of lesion, sub-therapeutic anticonvulsant levels, and postoperative local organic lesions were important factors causing the immediate postoperative seizures. Among them, a survey of postoperative computed tomography scans disclosed nine intracerebral hemorrhages, eight cases of cerebral edema, and four cerebral infarctions in the 44 patients; such major complications had a significant correlation with postoperative seizures (p less than 0.005).

Epidermoid tumors of Meckel's cave: case report and review of the literature.

Lesions of Meckels cave are extremely uncommon and difficult to diagnose. The symptoms and signs are variable, and the lesions may not appear on routine roentgenographic or computed tomographic examination. A patient with a small epidermoid tumor of Meckels cave that was diagnosed by magnetic resonance imaging is herein reported. The epidermoid appeared as a low-intensity mass on the T1-weighted image and as a high-intensity mass on the T2-weighted image. Coronal sections defined the anatomic relationship to the trigeminal nerve. Preoperative recordings of the trigeminal sensory evoked response may be predictive of postoperative recovery of neurological deficits. Furthermore, intraoperative recording was extremely useful in avoiding inadvertent neurological injury. Review of the literature confirms the rarity of this lesion and the usefulness of magnetic resonance imaging in diagnosing it, although based on a limited number of cases.

Long-term observations in cases with spontaneous carotid-cavernous fistulas

Twenty-six cases with spontaneous carotid-cavernous fistulas were followed up for periods ranging between 4 months and 9 years 8 months. A complete regression of symptoms without reappearance for more than 6 months was noted in 19 cases, a marked improvement in 2 cases, and a moderate regression in 3 cases. In 2 cases, symptoms have continued for 9 years 8 months and for 1 year. The regression of symptoms was usually delayed in patients less than 60 years old, in cases in which the symptoms developed slowly, and in cases with multiple draining veins. According to our observations a regression of symptoms may occur after very slight changes of haemodynamics. Compression of the cervical carotid artery for a short time or a temporary occlusion of the carotid artery by a balloon catheter should be considered as the treatment of choice in the first instance in cases with spontaneous carotid-cavernous fistulas showing relatively low pressure and low flow shunt.

Intraoperative Monitoring of the Motor Function: Experimental and Clinical Study

Manipulation of the lesions adjacent to the primary motor area or the motor pathway is troublesome for neurosurgeons because they lack an effective method to determine the primary motor area or to monitor motor function in the operative room. It will be of great value to establish a monitoring method of the corticospinal tract under general anaesthesia. We recorded the motor evoked potential (MEP) from direct motor cortex stimulation in cats and showed that it derives almost purely from the corticospinal tract. Then we used this technique during the operation of the resection of tumours near the primary motor area or the motor pathway. 1. Experimental study: Twenty adult cats were used in this study. Recording electrodes were flexible bipolar catheter electrodes inserted into the spinal epidural space. Stimulating electrodes were silver ball electrode on the cortex (anode) and needle electrode in the temporal muscle (cathode). Stimulation of 4-24 V, 5-10 Hz and 0.2 msec in duration were done and evoked potentials signals were averaged 60 to 512 times. MEP with multiple peaks was obtained that had a 112 msec conduction velocity in the spinal cord. We found the same signals from the stimulation of ipsilateral cerebral peduncle. Radiofrequency lesioning of ipsilateral cerebral peduncle produced a loss of MEP. These results show that MEP derives from the corticospinal tract. Significant wave form change, with components of short latency, was noted by the excessively intense stimuli. We supposed that superimposition of the signals from the extrapyramidal pathways, excited in the brain stem, results in this change.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinicophysiological Aspect and Treatment in Cases with Spontaneous Carotid-cavernous Fistula

Thirteen cases with spontaneous carotid-cavernous fistula found in our clinic during the last 5 years were analyzed. The age ranged from 24 to 74 years, and 12 were women. Initial symptoms were diplopia in 3 cases, severe orbital pain or headache with nausea and vomiting in 3 cases, dull pain around the orbit in 3 cases, red eye in 2 cases and tinnitus in 2 cases. Sings and symptoms at admission were conjuctival injection in 10 cases, chemosis in 5 cases, exophthalmos ranging from 2 to 9 mm, in 10 cases, bruit in 7 cases, disturbance of ocular movement in 7 cases, impairment of visual acuity in 4 cases, orbital pain or headache in 6 cases and tinnitus in 8 cases. Angiograms showed that in all cases dural branches of the internal carotid artery were contributors to the shunt and in at least 5 cases branches of external carotid artery were also contributors. There were positive correlation between angiographic findings and certain signs and symptoms. In all 3 cases with prominent venous drainage, disturbance of visual acuity and ocular movement were noticed. In another 10 cases, disturbance of visual acuity and ocular movements were found in one case and 4 cases, respectively. Furthermore, in 10 cases with posterior venous drainage via the inferior petrosal sinus, 8 cases complainted of tinnitus, but other 3 cases without showing posterior drainage, did not complain of tinnitus. Cerebral hemodynamic study was performed in 8 cases. In 7 cases rCBF values were normal and the relative shunt rate was small (10 ?? 23%). In another one case rCBF could not be measured because the shunt rate of the affected internal carotid artery was 100%. These results coincided with the angiographic findings. Twelve cases were not operated on and follow-up study ranging from 9 months to 5.2 years were carried out. Clinical symptoms were alleviated in 4 cases and completely disappeared in 8 cases. The follow-up angiography in the latter 3 cases showed disappearance of the shunt. Consequently, in cases with small blood deprivation through the shunt and mild clinical symptoms, conservative treatment is recommended unless exacerbation is not noticed.

The Indication for Surgical Treatment in Patients over 60 Years of Age with the Ruptured Intracranial Aneurysm

Fourty-eight cases over 60 years of age with the ruptured intracranial aneurysm were surgically treated. Satisfactory occlusion of the aneurysm with clipping of ligation was attained in 44 cases and plastic coating was performed in 4 cases. In 3 cases with a large intracerebral hematoma, the early operation was carried out and 2 cases died of the gastrointestinal bleeding and progressive cerebral vasospasm after the operation. In 45 cases, the operation was carried out more than 2 weeks after the subarachnoid hemorrhage. In 4 cases (9%), additional neurological symptoms developed after the operation and the occlusion of the main cerebral artery occured in 2 cases out of these cases related to the operative procedure. Three cases (7%) died of rebleeding due to the incomplete clipping, acute emphysema and agranulocytosis respectively. Thirty-five cases were followed up for 3 months to 10 years. At the time of this follow-up study, 25 (71%) were either free from symptoms or only with minor neurological deficits. Seven cases (20%) had moderate to severe symptoms; 4 cases had complications noticed more than 1.5 months after the operation and considered to be unrelated to the surgical maneuvar, 2 cases had various neurological deficits exsisted before the operation and only one case had the deficit related to the operative procedure. Three cases (9%) had died of pulmonary carcinoma and pneumonia 3 months to 10 years after the operation. Eighteen cases, including 10 cases over 65 years of age, were operated with microsurgical techniques more than 2 weeks after the bleeding. In this group, only one case died of agranulocytosis and no case became disabled. These results indicate that the direct intracranial operation using microsurgical techniques should be the first choice of the treatment in aged patients who are able to make a daily living without any complaints and do not have severe complications before the bleeding. Furthermore, even when prolonged initial unconsciousness and arteriosclerosis of intracranial vessels are present, the operation can be performed safely by delicate procedures using microsurgical techniques.