Amyloid Deposits in Supratentorial Meningiomas: Clinicopathological and Immunohistochemical Study

Amyloidosis is the definition for a group of diseases that have, in common, the infiltration of one or more tissues by an abnormal protein material-the amyloid substance, which is detected histologically by their green polarization color after Congo red staining. Despite increased interest on basic nature of amyloidosis by recent immunohistochemical or experimental study, the knowledge about the incidence and neurotoxic effect of cerebral amyloid or concomitant occurrence with brain tumor is still inchoate. We examined the incidence and clinico-pathologic characteristics of the patients with amyloid deposits in supratentorial meningiomas. Particularly about their neurotoxic effect to adjacent brain is considered one of the possible cause of seizure in 33 patients who underwent resection surgery for meningioma at the Keimyung University during the past three years. The pathological review and subgrouping by histologic type were done in all 33 specimens with sufficient size of paraffin block, defined by their morphology and polarization color after Congo red staining for diagnosis of amyloid deposits localized in the tumor. Immunohistochemical studies using monoclonal antibodies for amyloid-A protein(AA) and beta-amyloid(A beta) were evaluated to identify subtypes of amyloidosis. The rate of incidence of amyloid deposit in meningioma was 21%, i.e. seven out of thirty three cases. All laboratory findings and clinical studies did not suggest a systemic form. Seizure occurrence was one out of seven cases(14%), which was of no statistical significance. Immunohistochemical study for AA subtype was all negative, but showed all positive for A beta protein around the vessels. Recent reports has also demonstrated that Amyloid precusor protein(APP) and A beta is related in Alzheimer's disease, hereditary cerebral hemorrhage with amyloidosis-Dutch type(HCHWA-D) and amyloid angiopathy. Our research data indicates that the incidence of amyloid deposit is as high as 21% in supratentorial meningiomas. It seems that it is one of the possible cause of seizure. Nonsystemic microdeposits of amyloid and their subtype and it's relationship to neurotoxic effect in meningiomas remain to be confirmed by immunoelectron microscopic examination or immunohistochemical methods.

Cerebral Infarction Size According to the Duration of the Middle Cerebral Artery Occlusion in the Reversible and Irreversible Ischemic Infarction Models in the Rat

To establish a simple recirculation model in rats without craniectomy and to determine the recirculation time necessary to benefits the infarction area with restoration of the blood flow in a series of 30 adult rats, the authors induced irreversible ischemia(group I) in 15 rats through unilateral occlusion of the middle cerebral artery(MCA) by inserting a 16mm length of 4-0 nylon surgical thread through the internal carotid carotid artery(ICA). Reversible ischemia(group II) was induced by pullin the thread that occluded the MCA with hours recirculation in 5 rats. The author again divided the rats into 4 hours(Ia and Iia), 6 hours(Ib and Iib) and 12 hours(Ic and Iic) groups designated as according to the sacrifice time of rats in group I and the starting time of recirculation in group II following the MCA occlusion. The percentage of the infarction area to the total brain was calculated by a computer image analysis system, and the infarction size between reversible and irreversible groups were compared. The results showed that although the total average infarction sizes of irreversible ischemic groups were larger than those of reversible ischemic groups, the difference of the infarction size between each group o irreversible and reversible ischemia was not significant(group Ia Vs. Iia:7.78+/-8.37% Vs. 3.28+/-1.98%; group Ib Vs. Iib: 9.07+/-4.72% Vs. 6.61+/-3.19;group Ic Vs. Iic: 8.35+/-4.47% Vs. 6.90+/-6.07%. p>0.05, one-way ANOVA test). However, the degree of difference of the infarction size between irreversible and reversible ischemia decrease along with the prolongation of ischemic duration(difference between group Ia and IIa:4.5%;group Ib and Iib:2.46%;group Ic and Iic:.45%. The author concludes that ischemic brain injury may be decreased by making a restoration of the blood flow within 4 hours after occlusion of a blood vessel in rats, and this kind of reversible ischemic model may be useful in various studies on the focal cerebral ischemia without manipulation of the brain tissue and blood vessel.

Result of Surgical Management of Pituitary Tumor

The authors report results of surgical management in seventy-four cases of pituitary tumor who were treated in the department of neurosurgery, Keimyung University from Jan. 1987 to Dec. 1992. The composition of cases are prolactinoma in twenty-six cases, growth hormone(GH) secreting tumor in twenty, adrenocorticotropic hormone(ACTH) secreting tumor in three, thyrotropic hormone(TSH) secreting tumor in one and nonsecreting tumor in twenty-four cases. Fourty cases(54.1%) showed suprasellar and/or parasellar extension in the radiological studies. The modialites of management were surgery only in fourty-seven cases and surgery with radiation therapy in twenty-seven cases. Bromocriptin was medicated in twenty-two cases postoperatively. The management results in cases of prolactinoma, thirteen(50.0%) cases were cured and eight(30.8%) cases were improved. In the cases of GH secreting tumor, ten(50%) cases were cured and five(25%) cases were improved. Among three cases of ACTH secreting tumor, two cases were cured and there was one case of TSH secreting tumor which was cured. The worst management result were noticed in the cases of GH secreting tumor which extended suprasellar and/or parasellar region. of the thirty-five cases who had preoperative visual impairment(twenty-one cases of functional tumor and fourteen cases of nonfunctional tumor), twenty-seven(77.1%) cases were improved, sex(17.1%) cases not improved and two(5.7%) cases aggravated. The common complications after surgical management were hypopituitarism(eleven cases) and transient diabetes insipidus(nine cases). Recurrence was noticed in one case during follow-up period and three cases were expired, wtih one case during perioperative period and two during follow-up period. We conclude that an extensive effort should be made to diagnose early and advance surgical technique so as to improve the results of surgical management of the pituitary tumor.