Kenro Sunami

Hypermetabolic state following experimental head injury

AbstractLocal cerebral glucose utilization (LCGU) was studied in 35 conscious rats after a fluid percussion injury (cerebral contusion). The experiments were divided into two parts.(I)Natural course: LCGU was quantitatively measured in 17 rats by the14C-deoxyglucose autoradiographic method (Sokoloff et al. 1977) at 1, 2, 4 and 24 hours after injury. Sham operation was made in six rats.(II)DC-potential and LCGU: LCGU was studied with DC-potential and EEG monitoring in 12 rats. Results were as follows: (I) i) Glucose uptake was reduced at the center of the contusion in all cases. ii) Two different effects were observed in LCGU change two hours after injury: normal or slight increase in four of six rats (type A) and a remarkable increase in the cortex of the injured hemisphere in two of six rats (type B). iii) The pattern of increase in LCGU (type B) resembles that of cortical spreading depression.(II) i) Negative shift of DC-potential concomitant with EEG suppression in the injured hemisphere was observed frequently one to two hours after injury. ii) The increased LCGU pattern during DC-potential negative shift was identical with that of type B. iii) LCGU pattern without DC-potential change resembles that of type A.We concluded that the hypermetabolism occurring in the damaged cortex was due to a spreading depression. The findings obtained here should yield very important information concerning pathogenesis and treatment of human head injury.

MRI Prediction of Fibrous Pituitary Adenomas

Summary The transsphenoidal approach is a less invasive and safer procedure for removing pituitary adenomas. However, this procedure becomes extremely difficult when the tumour consistency is fibrous as encountered in about 10% of pituitary adenomas. In this study, we investigated predicting factors of tumour consistency in magnetic resonance images (MRIs). MRIs of two groups, twenty-one soft and five firm (fibrous) adenomas, were retrospectively evaluated and compared in respect of tumour consistency. To compare the two groups objectively, tumour densities on MRI films and percentage of collagen content on operative specimens were expressed as numerical data using NIH-imageTM. The relationships between collagen content and T1-weighted images, T2-weighted images, grade of enhancement effect, and heterogeneity of enhancement were investigated. Signal intensities on T1-weighted images were not correlated with tumour consistency, whereas those on T2-weighted images were significantly correlated with the percentage of collagen content. Adenomas, showing lower signal intensities on T2-weighted images, contained more collagen. On enhanced images, homogeneously enhanced adenomas tended to include more collagen, even though the grade of enhancement effect showed only weak correlation with the tumour hardness. MRIs give us useful information on tumour consistency. Adenomas may be firm and fibrous if they show low signal intensities on T2-weighted images and homogeneous enhancement. To remove such tumours, a long sized and small-calibred ultrasonic aspirators applicable to transsphenoidal approach must be prepared and multi-staged operations may be more than likely needed.

MRI Findings and Clinical Manifestations in Rathke's Cleft Cyst

Summary We retrospectively analysed patients with histologically proven Rathkes cleft cyst (RCC) in relation to the clinical manifestations and MRI findings, in particular, of cyst size and intensity in order to obtain an insight into their growing mechanisms, clinical presentations and their management. Eleven patients with RCC were divided into two groups based on T1 weighted images(WI). The A group consisted of 4 patients with cyst of low intensity in T1 WI. The age averaged 64.5 years. Their initial complaints were visual field defects(VFD). Their complaints were rather insidious. The maximum cyst size averaged 27.8±2.4 mm. The B group consisted of 7 patients with cyst of iso- or high-intensity in T1 WI. Two patients in the B group showed mixture of low and high and iso- and high-intensity, suggesting the presence of bleeding at the onset of symptoms or growing mechanism of the cysts. In the B group the age averaged 39.9 years, being lower than that in the A group. (P=0.0140 with Mann-Whitneys U test) The 5 patients out of 7 showed headache of insidious type or acute onset and the 3 showed a fluctuation of the VFD. The average size was 21.7±3.5 mm and smaller than that of the A group. (P=0.0298 with Mann-Whitneys U test) Our study has shown that the cyst with iso-to high intensity on T1 WI may cause clinical symptoms with a smaller size than cysts of the low intensity. In the former cyst pattern the onset and growing mechanism may be related to bleeding. The patients with this pattern are more likely to have acute and/or fluctuation of clinical presentations. Knowing these various clinical manifestations based on MRI pattern will be of help in following and managing patients with RCC.

Hemorrhagic type moyamoya disease.

The clinical picture of hemorrhagic type Moyamoya disease was analyzed in 20 cases. Hematoma at the basal ganglia was noted in 40% of cases, intraventricular hemorrhage (IVH) in 30%, thalamic hemorrhage with ventricular rupture in 15% and subcortical hemorrhage in 5%. The location was undetermined in two cases (10%) due to bleeding in the pre-computed tomography (CT) era. The frequencies shown above were correlated well to previous reports. In magnetic resonance imaging (MRI) performed 1 year or more after IVH, the primary bleeding site was demonstrated at the lateral wall of lateral ventricle, in portion density weighted and T2 weighted images. MRI can detect the site of old bleeding points and its chronological change if the study is repeated. In a follow-up period of 6.2 years, 35% of the cases had rebleeding once or twice. The second bleeding occurred seven times and the third twice. IVH occurred five times and the most common, basal ganglia hematoma three times while thalamic hemorrhage once. As a result, the rate of good outcome was 60% after the first bleeding and 40% after rebleeding. The mortality rate was 5% after the first 25% after rebleedings. Factors related to rebleedings and their poorer outcome are sex (with women being more susceptible), massive ICH and early recurrence. Rebleeding worsened the outcome. Therefore, prevention of rebleeding is important. From a therapeutic viewpoint, although a close relation between rebleeding and untreated hypertension could not be established, blood pressure control is critical at the both acute and chronic stages. Bypass surgery for bleeding type of Moyamoya disease seems to be less promising than ischemic type, even though a definite answer may not be obtained from our small number of cases.

Changes of local cerebral glucose utilization, DC potential and extracellular potassium concentration in experimental head injury of varying severity

SummaryThe negative shift of DC potential was associated with an increase of extracellular potassium and energy metabolism. Therefore this dramatic phenomenon following the trauma to the brain was thought to be identical to spreading depression.1.Spreading depression was most frequently observed between one and two hours after injury.2.Spreading depression can be elicited in the deep structures as well as in the cortex. The more severe the injury, the more frequently the negative shifts were observed. The DC index seems to correlate well with the severity of the experimental model. It is concluded that the energy metabolism after the brain contusion was different from structure to structure and was changing continuously in the course of time.

Slit ventricle syndrome after cyst-peritoneal shunting for temporal arachnoid cyst in children--a clinical entity difficult to detect on neuroimaging study.

Slit ventricle syndrome, known to occur from malfunction of the shunt procedure for hydrocephalus, is reported after cyst-peritoneal shunt for temporal arachnoid cyst. Two children aged 12 and 10 years, who underwent cyst-peritoneal shunting for a large temporal arachnoid cyst at the age of 10 and 5 years, respectively, recently experienced several episodes of severe headache. Prior to admission, repeated CT scans did not reveal any morphological change in either of these two patients. Evidence of high intracranial pressure by lumbar tap revealed shunt malfunction. Both patients became free of neurological complaints and deficits after shunt revision. Despite elevated intracranial pressure due to shunt malfunction, neuroimaging studies showed no morphological changes in slit ventricle syndrome. Delay in both the diagnosis and prompt treatment may result in complete loss of visual acuity and even death. It is important to suspect this complication in patients with persistent elevated intracranial pressure symptoms and signs after any shunting procedure, regardless of unchanged neuroimaging studies. Once this is suspected, lumbar tap may be necessary and the choice of treatment is shunt revision.

Heavily T2 weighted MR images of anterior optic pathways in patients with sellar and parasellar tumours - prediction of surgical anatomy.

Summary Objective. Location of anterior optic pathways in sellar and parasellar tumours was preoperatively evaluated, by use of heavily T2 weighted MR images. Methods. Heavily T2 and conventional T1 weighted images were studied in 20 patients with sellar and parasellar tumours who underwent craniotomy. Pathology revealed pituitary adenoma in 5 patients, craniopharyngioma in 8 and parasellar meningioma in 7. Maximum sizes ranged from 15 mm to 58 mm. Sequence parameters of TR/TE for heavily T2 weighted and T1 weighted images were 5800/220 msec and 600/20 msec, respectively, and slice thickness was 3 mm for both. Results. The anterior optic pathway was detected in 95% on heavily T2 weighted images and 50% on T1 weighted images. All preoperative heavily T2 weighted images were compatible with operative findings. The optic chiasms were most commonly supero-posterior in pituitary adenomas, anterior (prefixed) in craniopharyngiomas and posterior in meningiomas. The optic nerves were commonly located superior or lateral to the tumours. However, parasellar meningiomas, off the midline, revealed the optic nerves in various locations, depending on the tumour origin. In such tumours, heavily T2 weighted images provided surgical information on the width of the working space through prechiasmal and/or optico-carotid spaces in the pterional approach. Spatial relation of the tumours to the lamina terminalis, anterior commissure and anterior communicating artery complex was clearly shown in craniopharyngioma patients, who underwent the anterior interhemispheric approach. Conclusion. Heavily T2 weighted MR images are useful in determining the location of optic pathways and surgical approach and in individual prediction of the anatomy for even large sellar and parasellar tumours.

Delayed postoperative CSF rhinorrhea of intrasellar arachnoid cyst.

Summary CSF rhinorrhea due to a transsphenoidal approach usually follows accidental or intentional arachnoid opening. We report a patient with an intrasellar arachnoid cyst, who developed delayed onset of CSF rhinorrhea. A sixty-two-year-old man presented with bitemporal type visual field defect for the last 3 years. With the diagnosis of arachnoid cyst or Rathkes cleft cyst, based on MRI findings of intra-and supra-sellar cyst with CSF intensity, he successfully underwent transsphenoidal surgery without evidence of intra-operative CSF leakage. He developed CSF rhinorrhea one week later. This needed another operation for sellar floor repair. The pathomechanism of this delayed onset is explained as follows. Incomplete or one-way communication of subarachnoid space to cyst cavity, unrecognized during surgery, might cause delayed onset of CSF rhinorrhea. By using MRI, identification of the residual gland, which was compressed posteriorly, is useful for differentiating an arachnoid cyst from other cystic lesions. In highly suspect cases, even without evidence of intra-operative CSF leakage, peri-operative measures to prevent occurrence of postoperative CSF rhinorrhea are required.

Identification of Cerebral Infarction-Specific Antibody Markers from Autoantibodies Detected in Patients with Systemic Lupus Erythematosus

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease which may be caused by development of the autoantibodies. On the other hand, SLE is a high-risk group of atherosclerosis, so it is possible that some of autoantibodies in SLE are the result of atherosclerosis-related diseases such as cerebral infarction (CI), cardiovascular disease (CVD) and diabetes mellitus (DM). Methods: The initial screening of autoantibodies was performed using the protein array method. AlphaLISA was used to analyze the serum antibody levels using synthetic polypeptides as antigens. Results: After the initial screening using protein array, we identified 67 antigens that were recognized by IgG antibodies in sera of patients with SLE. In the second screening, 170 peptides derived from amino acid sequences of 67 antigens were synthesized and used as antigens for analysis of serum antibody levels by AlphaLISA. The antibody levels for ten peptides were significantly higher in the sera of patients with SLE than in those of healthy donors. Further AlphaLISA analysis of sera of patients with CI, CVD or DM revealed that the serum antibody levels for four peptides derived from SOSTDC1, CTNND1, CLDND1 and CCNG2 were elevated in patients as compared to those of healthy donors. Conclusions: Serum antibody levels against peptide antigens of SOSTDC1, CTNND1, CLDND1 and CCNG2 are useful markers for diagnosis of the progression of CI, CVD and/or DM.

Heavily T2 weighted MR assessment of fornical injury after anterior interhemispheric approach for large suprasellar tumors.

Summary Fornical injury in transforaminal approach is well known. Its injury in the anterior interhemispheric approach (AIA) has been rarely highlighted. We report 2 cases with a large suprasellar tumor who underwent AIA. Postoperative heavily T2 weighted reversed (T2R) MR images demonstrated its unilateral injury. The clinical significance of symptom-free fornical injury after AIA is discussed. Cases 1 and 2 were a 15 year-old girl with a meningioma and a 49-year-old woman with a craniopharyngioma, respectively. They underwent AIA. Postoperative T2R images revealed unilateral fornical crus atrophy. They did not present associated memory deficits. Case 1 had the injury of both fornical column and anterior commissure. They were speculatively torn by intra-operative lateral retraction of the frontal lobes. Case 2 had unilateral atrophy of the mammillary body and postcommissural fornix, which were probably caused by ischemic damage related to surgical manipulation, since case 2 had an associated anterior thalamic infarct. During the operation for large suprasellar tumors, excessive laterally directed brain retraction should be avoided, since such manipulation may easily tear the overstretched anterior commissure and fornical column. Once we notice or suspect fornical injury on MR studies in cases of re-operation, we have to choose a surgical approach and operative manipulation to preserve an intact fornix. The MR evaluation of fornix should be included in the peri-operative radiological assessment, since patients with unilateral fornical injury were free of memory disturbance, and T2R imaging is a useful MR sequence for depicting the anatomy related to the fornix.