Septo-optic dysplasia, first described by de Morsier in 1956, is an uncommon congenital midline structural abnormality of the brain, including agenesis of septum pellucidum, primitive optic ventricle and dysplasia of the optic chiasm, optic nerves, and infundibulum. Agenesis of septum pellucidum, initially thought to be an integral part of this syndrome, is inconstant and not an essential part of the disorder. Also, it reveals a variable spectrum of associated abnormalities in disturbed hypothalamic-pituitary function. We recently experienced 3 patients of septo-optic dysplasia who showed bilateral optic disc hypoplasia clinically and midline structural abnormalities in computerized tomography(CT) or magnetic resonance imaging(MRI).
Brain ; Humans ; Optic Chiasm ; Optic Nerve ; Septo-Optic Dysplasia* ; Septum Pellucidum

PURPOSE: This is study of whether 3-D conformal radiotherapy for carcinomas of the ethmoid sinus were better than those treated with conventional 2-D plan. MATERIALS AND METHODS: The 3-D conformal treatment plans were compared with conventional 2-D plans in 4 patients with malignancy of the ethmoid sinus. Isodose distribution, dose statistics, and dose volume histogram of the planning target volume were used to evaluate differences between 2-D and 3-D plans. In addition, the risk of radiation exposure of surrounding normal critical organs are evaluated by means of point dose calculation and dose volume histogram. RESULTS : 3-D conformal treatment plans for each patient that the better tumor coverages by the planning target volume with improved dose homogeneity, compared to 2-D conventional treatment plans in the same patient. On the other hand, the radiation dose distributions to the surrounding normal tissue organs, such as the orbit and optic nerves are not significantly reduced with our technique, but a substantial sparing in the brain stem and optic chiasm for each patient. CONCLUSION : Our findings represented the potential advantage of 3-D treatment planning for dose homogeniety as well as sparing of the normal tissue surrounding the tumor. However, further investigational studies are required to define the clinical benefit.
Brain Stem ; Ethmoid Sinus* ; Hand ; Humans ; Optic Chiasm ; Optic Nerve ; Orbit ; Radiotherapy, Conformal*

Cavernous malformations (CMs) arising from the optic nerve and chiasm are extremely rare. The authors present a case of 39-year-old woman with CMs of the optic chiasm. She was referred due to sudden onset of bitemporal hemianopsia and headache, the so-called 'chiasmal apoplexy'. MRI findings suggested a diagnosis of hemorrhage and vascular malformation of the optic chiasm. Pterional craniotomy revealed an intrachiasmatic cavernous malformation with hemorrhage. The malformation was totally excised, but field deficits remained unchanged after surgery.
Adult ; Caves ; Craniotomy ; Female ; Headache ; Hemianopsia ; Hemorrhage ; Humans ; Optic Chiasm ; Optic Nerve ; Stroke ; Vascular Malformations

A twenty nine-year-old woman has suffered for ten years from progressive proptosis and loss of vision in the right eye. Her right eye had deviated out-and-upwards, and its visual acuity was tested by hand motions. With the help of a brain and orbit CT, the tumor was found around the optic nerve and in the parasellar area. This tumor was surgically removed twice by Kroenlein operation and craniotomy, and was treated with irradiation(total dose: 5400 RAD). It was histopathologically diagnosed as astracytoma grade I. In the consecutive study, no evidence of recurrence of the tumor in either the orbit or brain was found.
Brain ; Craniotomy ; Exophthalmos ; Female ; Hand ; Humans ; Optic Chiasm* ; Optic Nerve Glioma* ; Optic Nerve* ; Orbit ; Recurrence ; Visual Acuity

The association of abnormalities of the optic nerves, optic chiasm, and optic tracts with anomalies of the midline structures in the brain-an absent septum pellucidum etc was reported and called "septo-optic dysplasia". Also, it was noted that septo-optic dysplasia could be associated with hypopituitary dwarfism. It occurs more commonly in first born children and children born to young or diabetic mothers. We report a case of septo-optic dysplasia with literature, who had complained of severe visual impairment associated with nystagmus, bilateral optic nerve hypoplasia, absent septum pellucidum, and normal range of hormone studies.
Child ; Dwarfism ; Humans ; Mothers ; Optic Chiasm ; Optic Nerve ; Reference Values ; Septo-Optic Dysplasia* ; Septum Pellucidum ; Vision Disorders ; Visual Pathways

To demonstrate the effect of diaschisis and to evaluate its possible mechanism in acute unilateral infarction, the changes of regional cerebral flows(rCBF's) on the both MCA territories and both cerebellum were measured by the hydrogen clearance method using the unilateral cerebral and cerebellar infarction model. Cerebral infarction model was made by left middle cerebral artery(MCA) occlusion through the transorbital approach and cerebellar infarction was made by coagulation of cerebellar vessels through retromastoid craniectomy. Experimental groups consisted of left MCA occlusion group-12cats, left MCA occlusion with callosal section group-15cats and cerebellar infarction group-13cats. After measurement of rCBF for 8 hours at fixed intervals the animals were sacrificed and immediately thereafter 50ml of 2% triphenyl tetrazolium chloride(TTC) solution was immediately injected in order to examine the size of infarction. The results were as follows ; 1) After occlusion of left MCA, the rCBF of ipsilateral MCA territory decreased abruptly and significantly(p<0.001), reaching unmeasurable value 1 hour after occlusion. The rCBF of contralateral cerebellum decreased 25.5~32.6% of control value. On the ipsilateral MCA territory the rCBF decreased 18.5~41.0% and the rCBF of ipsilateral cerebellum decreased 19.0~30.0% of control value(p<0.01). 2) In the group of left MCA occlusion with callosal section, the rCBF of contralateral MCA territory decreased 4.8~16.4% of control value but it is less marked and not significant statistically(p>0.05). 3) In the group of cerebellar infarction, the rCBF of contralateral cerebellum and both MCA territories did not decrease significantly in either group of cerebellar blood flow less than 10ml/ 100g/min or 10~20ml/ 100g/min. 4) In the experimental group of left MCA occlusion, infarction revealed 40.2+/-2.8% of coronal plane through the optic chiasm showing high percentage of infarction yield with small standard deviation. In the cerebellar infarction model the extent of infarction was 36.0+/-10.0% of horizontal planes of cerebellum in the group of rCBF below 10ml/100g/min. In the group of rCBF of 10~20ml/100g/min the extent of infarction was 22.0 +/-12.0%. These findings show the crossed cerebellar as well as interhemispheric diaschisis and support the importance of neural pathway in the mechanism of diaschisis. However further studies for long-term results and mechanism of diaschisis are needed.
Animals ; Cerebellum ; Cerebral Infarction* ; Corpus Callosum ; Hydrogen ; Infarction ; Middle Cerebral Artery ; Neural Pathways ; Optic Chiasm

To demonstrate the effect of diaschisis in acute unilateral cerebral infarction, the changes of regional cerebral and cerebellar blood flow(rCBF) following experimental occlusion of one middle cerebral artery(MCA) were studied in 15 mongrel cats, following occlusion of left MCA by coagulation using transorbital approach, rCBF's of both MCA trerritories and both cerebellum were measured simultaneously by the hydrogen clearance technique. Sham operation group consisted of 5 cats, in which transorbital exposure of left MCA was performed and the rCBF's were measured in the same manner as the experimental group without cauagulation of left MCA. After measurement of rCBF for 8 hours at fixed intervals, the animals were sacrificed and immediately thereafter 25 ml of 2% triphenyl tetrazolium chloride(TTC) solution was injected through each common carotid artery. The brain was removed and immersed in 10% buffered fomalin solution for two weeks, then the coronal plane through optic chiasm was examined for the cerebral infarction. As results, contralateral MCA territory and both cerebellum showed diaschisis after occlusion of left MCA, and contralteral cerebellar rCBF decreased more, showing characteristics of crossed cerebellar as well as interhemispheric diaschisis. Sham operation group showed no infarction, and in experimental group 40.2+/-1.3% of the coronal plane through the optic chiasm was infracted, showing high percentage of infarction with small standard deviation.
Animals ; Brain ; Carotid Artery, Common ; Cats ; Cerebellum ; Cerebral Infarction* ; Hydrogen ; Infarction ; Middle Cerebral Artery ; Optic Chiasm

PURPOSE: MR is the most useful imaging method in evaluating the anatomic changes of the optic chiasm (OC). The purpose of this study is to investigate the relationship between the OC displacement and visual manifestations. MATERIALS AND METHODS: We retrospectively reviewed 44 patients who showed displacement of OC on brain MR. The pattern of OC displacement was classified into 3 groups according to following criteria: group A included the patients with OC displacement only due to empty sella;group B represented the patients with OC displacement by a lesion and the border between the lesion and OC was distinct;and group C was the patients with OC displacement by a lesion and had a indistinct border or thinning of the OC. RESULTS: Visual symptoms and signs were noted in 12 patients and the most common sign was bitemporal hemianopsia. In group A(7 patients), the visual symptoms and signs were seen in only one patient(14%), in whom contracted visual fields persisted since previous pituitary apoplexy had developed. In group B(30 patients), the visual symptoms and signs were seen in 4 patients(13%) who had tumorous conditions except one case of cysticercosis. In group C(7 patients), the visual symptoms and signs were seen in all patients (100%). CONCLUSION: The more OC is compressed, the more the prevalence of visual symptoms and signs increases. However, there was no correlation between the occurrence of visual symptoms and the presence of OC displacement only without compression.
Brain ; Cysticercosis ; Hemianopsia ; Humans ; Optic Chiasm* ; Pituitary Apoplexy ; Prevalence ; Retrospective Studies ; Visual Fields

PURPOSE: Total scalp irradiation (TSI) is a rare but challenging indication. We previously reported that non-coplanar intensity-modulated radiotherapy (IMRT) was superior to coplanar IMRT in organ-at-risk (OAR) protection and target dose distribution. This consecutive treatment planning study compared IMRT with volumetric-modulated arc therapy (VMAT). MATERIALS AND METHODS: A retrospective treatment plan databank search was performed and 5 patient cases were randomly selected. Cranial imaging was restored from the initial planning computed tomography (CT) and target volumes and OAR were redelineated. For each patients, three treatment plans were calculated (coplanar/non-coplanar IMRT, VMAT; prescribed dose 50 Gy, single dose 2 Gy). Conformity, homogeneity and dose volume histograms were used for plan. RESULTS: VMAT featured the lowest monitor units and the sharpest dose gradient (1.6 Gy/mm). Planning target volume (PTV) coverage and homogeneity was better in VMAT (coverage, 0.95; homogeneity index [HI], 0.118) compared to IMRT (coverage, 0.94; HI, 0.119) but coplanar IMRT produced the most conformal plans (conformity index [CI], 0.43). Minimum PTV dose range was 66.8% –88.4% in coplanar, 77.5%–88.2% in non-coplanar IMRT and 82.8%–90.3% in VMAT. Mean dose to the brain, brain stem, optic system (maximum dose) and lenses were 18.6, 13.2, 9.1, and 5.2 Gy for VMAT, 21.9, 13.4, 14.5, and 6.3 Gy for non-coplanar and 22.8, 16.5, 11.5, and 5.9 Gy for coplanar IMRT. Maximum optic chiasm dose was 7.7, 8.4, and 11.1 Gy (non-coplanar IMRT, VMAT, and coplanar IMRT). CONCLUSION: Target coverage, homogeneity and OAR protection, was slightly superior in VMAT plans which also produced the sharpest dose gradient towards healthy tissue.
Brain ; Brain Stem ; Hemangiosarcoma ; Humans ; Mycosis Fungoides ; Optic Chiasm ; Radiotherapy, Intensity-Modulated* ; Retrospective Studies ; Scalp*

PURPOSE: Pilocytic astrocytoma is a benign tumor predominantly arising from cerebellum in pediatric age. But it occasionally arises in supratentorium. We describe radiologic findings of supratentorial pilocytic astrocytoma. MATERIALS AND METHODS: Eleven CT and 7 MR examinations in 11 patients were retrospectively reviewed with attention to location, CT density, MR signal intensity, and degree and pattern of contrast enhancement on CT and MR. RESULTS: The tumors were located around the third ventricle (hypothalamus in three cases, optic chiasm in three cases) and in cerebral hemisphere (temporal lobe in three cases, frontal lobe in one case, thalamus in one case). On CT, the tumors were all sharply demarcated and rarely associated with edema. The tumors showed moderate to strong contrast enhancement. Necrosis appeared frequently in tumors around the third ventricle in contrast to frequent cyst formation in hemispheric masses. On MR, the tumors appeared hypo- or isointense on T1- weighted images and hyperintense on T2- weighted images. After administration of contrast agent, the tumors showed intense enhancement more than that of CT. CONCLUSION: The typical location and radiologic findings described above are helpful in the diagnosis of the supratentorial pilocytic astrocytoma.
Astrocytoma* ; Cerebellum ; Cerebrum ; Diagnosis ; Edema ; Frontal Lobe ; Humans ; Necrosis ; Optic Chiasm ; Retrospective Studies ; Thalamus ; Third Ventricle