Glioma of the optic nerve and chiasm: a case report / Glioma óptico-quiasmático: um relato de caso

ABSTRACT This article reports the case of an 11-year-old male patient with a history of proptosis and low progressive visual acuity in the left eye. He presented with a best corrected visual acuity of 20/25 in the right eye and light perception in the left eye. Exotropia and limitation in adduction were observed in the left eye. On automated perimetry, inferiortemporal quadrantopsia was observed in the right eye, while total scotoma was observed in the left eye. On magnetic resonance imaging, there was an expansive lesion in the left optic nerve, extending to the brainstem with chiasmatic involvement. This article aims to report a case of optic pathway glioma, as well as to discuss its clinical findings and their interconnection with the current literature.

RESUMO Este artigo relata o caso de um paciente do sexo masculino, 11 anos de idade, com história de proptose e baixa de acuidade visual progressiva. Ao exame oftalmológico apresentava melhor acuidade visual de 20/25 em olho direito e percepção de luz em olho esquerdo. Existia exotropia e limitação à adução no olho esquerdo. À campimetria automatizada, observou-se quadrantopsia temporal inferior em olho direito e escotoma total em olho esquerdo. À ressonância magnética, evidenciou-se lesão expansiva em trajeto do nervo óptico esquerdo estendendo-se até região do tronco encefálico, com acometimento quiasmático. O objetivo deste artigo é relatar o glioma de vias ópticas, bem como discutir os achados e sua interligação com a literatura atual.

Resultado a largo plazo de una serie de fetos con agenesia aislada del septum pellucidum / Long-term postnatal outcome of fetuses with isolated agenesis of the septum pellucidum

Objetivo: Reportar el resultado a largo plazo de una serie de fetos con agenesia del septum pellucidum aislada (ASP), con medición de su quiasma óptico mediante neurosonografía fetal (NSG). Método: Se incluyeron todas las pacientes con ASP y NSG evaluadas desde el año 2008 a la fecha y con seguimiento hasta su edad escolar. En todos los casos se consignaron los datos clínicos de NSG y de resonancia magnética (RM), cuando esta se realizó. Se entrevistó telefónicamente a los padres. Resultados: Nueve pacientes cumplieron los criterios: cuatro con displasia septo-óptica (DSO) (rango de seguimiento: 5-14 años) y cinco sin DSO (rango de seguimiento: 7-10 años). Un décimo caso se excluyó por tener solo 6 meses de seguimiento. Ninguna de las ASP tuvo otra anomalía detectada en su seguimiento. Ninguno de los casos con DSO tuvo alteración del tamaño de su quiasma óptico en la NSG ni anormalidad en la vía óptica en la RM. Conclusiones: En nuestra población, el riesgo residual de DSO frente a ASP es del 44,4%. En el seguimiento, nuestra definición de ASP por NSG no tuvo falsos negativos con relación a otras anomalías de aparición posnatal, a excepción de la DSO.

Objective: To report the long-term outcome of a series of fetuses with isolated septum pellucidum agenesis (ASP) with measurement of their optic chiasm by fetal neurosonography (NSG). Method: All patients with ASP and NSG evaluated from 2008 to date and with follow-up until their school age were included. In all cases, clinical, NSG and magnetic resonance imaging (MRI) data were recorded. Parents were interviewed by telephone. Results: Nine patients met the criteria: four with septo-optic dysplasia (SOD) (follow-up range: 5-14 years) and five without SOD (follow-up range: 7-10 years). A tenth case was excluded because only 6 months of follow-up. None of the ASP cases had another anomaly detected in their follow-up. None of the cases with DSO had anomaly of the size of their optic chiasm on NSG or abnormality in the optical pathway in the MRI. Conclusions: In our population, the residual risk of DSO versus ASP is 44.4%. At follow-up, our NSG definition of ASP had no false negatives in relation to other postnatal-onset anomalies, except for SOD.

Traumatic chiasmal syndrome. Case report / Síndrome quiasmática traumática. Relato de caso

ABSTRACT Traumatic chiasmal syndrome is one of the rare etiologies of chiasmal syndrome, characterized by optic chiasm injury following head trauma. The main visual defect associated is bitemporal hemianopia with macular splitting; however, it can present with a variety of other visual defects and neurologic signs. The authors report a case of complete bitemporal hemianopia after head trauma, with multiple frontal and skull base fractures and no other neurologic deficits, or hypothalamic-pituitary abnormality. Most cases of traumatic chiasmal syndrome are caused by mechanical stretch or compression of the chiasma. Nevertheless, in this case, the radiologic findings excluded macroscopic disruption or external compression of the chiasma, raising the possibility of a contusion necrosis associated with functional impairment of the optic chiasma. Traumatic chiasmal syndrome must be considered in the differential diagnosis of patients presenting with complete bitemporal hemianopia after head injury caused by frontal and skull base fracture.

RESUMO A síndrome quiasmática traumática é uma das raras etiologias da síndrome do quiasma óptico, que se caracteriza pela presença de lesão do quiasma óptico causada por traumatismo craniencefálico. O principal defeito visual associado é a hemianopsia bitemporal com macular splitting. No entanto, pode se manifestar por uma variedade de outros defeitos visuais e sinais neurológicos. Os autores relatam um caso de hemianopsia bitemporal completa após traumatismo craniencefálico com múltiplas fraturas frontais e da base do crânio na ausência de outros défices neurológicos ou alterações do eixo hipotálamo-hipofisário. A maioria dos casos de síndrome quiasmática traumática é causada por estiramento mecânico ou compressão do quiasma. No entanto, no caso apresentado, os achados radiológicos excluíram lesão macroscópica ou compressiva do quiasma, levantando a possibilidade de uma necrose após contusão associada ao compromisso funcional do quiasma óptico. A síndrome quiasmática traumática deve ser considerada no diagnóstico diferencial de doentes que apresentam hemianopsia bitemporal completa após traumatismo craniencefálico, especialmente em casos de fratura do osso frontal e da base do crânio.

Molecular guidance cues in the development of visual pathway

70%-80% of our sensory input comes from vision. Light hit the retina at the back of our eyes and the visual information is relayed into the dorsal lateral geniculate nuclei (dLGN) and primary visual cortex (V1) thereafter, constituting the image-forming visual circuit. Molecular cues are one of the key factors to guide the wiring and refinement of the image-forming visual circuit during pre- and post-embryonic stages. Distinct molecular cues are involved in different developmental stages and nucleus, suggesting diverse guidance mechanisms. In this review, we summarize molecular guidance cues throughout the image-forming visual circuit, including chiasm determination, eye-specific segregation and refinement in the dLGN, and at last the reciprocal connections between the dLGN and V1.

Effects of sevoflurane on expression of Egr-1 and Egr-2 in suprachiasmatic nuclei of sleep-deprived rats / 中华麻醉学杂志

Objective To evaluate the effects of sevoflurane on the expression of early growth response gene 1 (Egr-1) and Egr-2 in the suprachiasmatic nuclei (SCN) of sleep-deprived rats.Methods Forty-eight pathogen-free healthy male Sprague-Dawley rats,were divided into 4 groups (n =12 each) using a random number table:control group (group C),sleep deprivation group (group SD),sevoflurane group (group SEV) and sleep deprivation plus sevoflurane group (group SD+SEV).The rats were subjected to sleep deprivation for 96 h in group SD.The rats inhaled 2.5％ sevoflurane for 3 h in group SEV.The rats inhaled 2.5％ sevoflurane for 3 h after being subjected to sleep deprivation for 96 h in group SD+SEV.The mechanical paw withdrawal threshold (MWT) was measured at 12 h,3 days and 7 days after emergence from anesthesia (T1-3).The animals were sacrificed after blood samples were obtained from the external carotid artery,and the cerebral SCN was removed for determination of Egr-1 and Egr-2 expression by Western blot.Results Compared with group C,the MWT was significantly decreased at T1-3 in SD,SEV and SD+SEV groups,the expression of Egr-1 and Egr-2 in SCN was significantly up-regulated at T1-3 in SD and SD+SEV groups,and the expression of Egr-1 in SCN was significantly up-regulated at T1-3,and the expression of Egr-2 in SCN was up-regulated at T1 in group SEV (P＜0.05).Compared with SD and SEV groups,the MWT was significantly decreased at T1-3 in group SD+SEV,and the expression of Egr-1 and Egr-2 in SCN was significantly up-regulated at T1-3 in group SD+SEV (P＜0.05).Conclusion The mechanism by which sevoflurane aggravates hyperalgesia is related to up-regulation of Egr-1 and Egr-2 expression in SCN of sleepdeprived rats.

A Large Ruptured Anterior Communicating Artery Aneurysm Presenting with Bitemporal Hemianopsia

Anterior communicating artery (ACoA) aneurysms sometimes present with visual symptoms when they rupture or directly compress the optic nerve. Giant or large ACoA aneurysms producing bitemporal hemianopsia are extremely rare. Here we present an unusual case of bitemporal hemianopsia caused by a large intracranial aneurysm of the ACoA. A 41-year-old woman was admitted to our neurosurgical department with a sudden-onset bursting headache and visual impairment. On admission, her vision was decreased to finger counting at 30 cm in the left eye and 50 cm in the right eye, and a severe bitemporal hemianopsia was demonstrated on visual field testing. A brain computed tomography scan revealed a subarachnoid hemorrhage at the basal cistern, and conventional cerebral catheter angiography of the left internal carotid artery demonstrated an 18x8 mm dumbbell-shaped aneurysm at the ACoA. Microscopic aneurysmal clipping was performed. An ACoA aneurysm can produce visual field defects by compressing the optic chiasm or nerves. We emphasize that it is important to diagnose an aneurysm through cerebrovascular study to prevent confusing it with pituitary apoplexy.

Bitemporal Hemianopsia in Ethambutol-Induced Optic Neuropathy

PURPOSE: To report three cases with bitemporal hemianopsia after using ethambutol to treat tuberculosis. CASE SUMMARY: A 50-year-old male with chronic renal failure and tuberculous pleurisy, a 57-year-old male with diabetic retinopathy and pulmonary tuberculosis, and a 59-year-old male with diabetes and pulmonary tuberculosis were referred for evaluation due to decreased visual acuity for several months after taking ethambutol to treat tuberculosis. All 3 patients had abnormal color vision and visual evoked potential in both eyes. Visual field showed bitemporal hemianopsia with or without central scotoma. Brain imaging tests were normal. Although ethambutol was discontinued in all three patients, one patient with renal disease showed further decrease in visual acuity and visual field worsened to total field defect. CONCLUSIONS: Ethambutol-induced optic neuropathy is a wide spectrum disorder and based on our cases, can present as bitemporal hemianopsia mimicking compressive chiasmal lesions. A thorough history should be taken and immediate discontinuation of ethambutol is recommended in cases when bitemporal hemianopia occurs.

Bilateral acute visual loss from Rathke's cleft cyst apoplexy in a patient with dengue fever / Perda visual aguda secundária a apoplexia de cisto de Rathke em paciente com dengue

Hemorrhagic complications of optic pathway diseases are extremely rare causes of acute visual loss associated with dengue fever. In this paper we report a patient presenting with dengue fever and bilateral acute visual loss caused by chiasmal compression due to Rathke's cleft cyst apoplexy. Considering the importance of early diagnosis and treatment to visual recovery, apoplexy of sellar and suprasellar tumors should be considered in the differential diagnosis of patients with acute visual loss and dengue fever.

Complicações hemorrágicas de doenças da via óptica são causas extremamente raras de perda aguda de visão em pacientes com dengue. Nesse trabalho, documentamos um caso de paciente com dengue apresentando perda de visão bilateral aguda secundária a compressão quiasmática por quadro hemorrágico em cisto de Rathke. Considerando a importância do diagnóstico e tratamento precoces para um bom prognóstico visual, a apoplexia de tumores da região selar e suprasselar deve ser incluída como um raro, porém importante, diagnóstico diferencial de perda visual aguda nesses pacientes.

A Case of Huge Pilocytic Astrocytoma Causing Eyeball Subluxation

PURPOSE: To report a relatively rare case of huge pilocytic astrocytoma of the optic nerve and optic chiasm causing eyeball subluxation. CASE SUMMARY: An eight-year-old male presented with proptosis and visual loss in the left eye for one year. The radiological findings showed a 2.9 x 2.7 x 4.2-cm tumor on the left optic nerve and optic chiasm. For diagnosis and treatment, the patient underwent tumor resection and enucleation. Pathohistological analysis of the tumor specimen revealed pilocytic astrocytoma, which is classified by the World Health Organization as a grade I astrocytic tumor. CONCLUSIONS: Astrocytoma is a tumor of the brain that affects children more often than adults. In general, gross-total resection of pilocytic astrocytoma is expected to be curative due to the non-invasive feature of the tumor. Considering pilocytic astrocytoma as differential diagnosis of orbital tumor in children with symptoms of rapidly progressive proptosis and decreased visual acuity is important because occurrence in the optic nerve and optic chiasm is possible.

Optochiasmatic tuberculoma as the sole manifestation of late recurrent tuberculosis / Tuberculoma opto-quiasmático como única manifestação de tuberculose recorrente tardia

Brain tuberculomas account for 10-20% of space occupying brain lesions in developing countries. Most lesions are observed at time of tuberculosis diagnosis or soon after starting treatment. We herein describe a 32 year-old patient with a 14-month history of headache and progressive visual loss. Her past medical history revealed pulmonary tuberculosis treated eight years before. A brain MRI showed a T1- and T2-weighted isointense contrast-enhancing lesion in the optic chiasm. A presumptive diagnosis of optochiasmatic tuberculoma was made and isoniazid, rifampin, pyrazinamide, and ethambutol were started. Despite treatment, the patient evolved to blindness. The prompt recognition of this condition is extremely important since the presence of optochiasmal enhancement is associated with blindness in patients with tuberculosis.

Tuberculomas cerebrais são responsáveis por 10-20% das lesões parenquimatosas em países em desenvolvimento. A maioria destas lesões é observada ao diagnóstico de tuberculose ou logo após o início do tratamento. Descrevemos um caso de uma paciente de 32 anos com história de 14 meses de evolução de perda visual progressiva e cefaleia. A história patológica revelou tuberculose pulmonar 8 anos antes. A ressonância magnética do crânio mostrou uma lesão isointensa nas sequências T1 e T2 captantes de contraste no quiasma óptico. Fizemos o diagnóstico presuntivo de tuberculoma ótico-quiasmático e inciamos isoniazida, rifampicina, pirazinamida e etambutol. Apesar do tratamento, a paciente evoluiu para amaurose bilateral. O rápido diagnóstico desta condição é extremamente importante já que a presença de captação de contraste está associada à amaurose em pacientes com tuberculose.

Avaliação da camada de fibras nervosas da retina nas afecções neuroftalmológicas da via óptica anterior / Retinal nerve fiber evaluation in neuro-ophthalmic diseases of the anterior visual pathway

A avaliação da camada de fibras nervosas da retina tem grande importância no diagnóstico e acompanhamento de várias afecções da via óptica anterior. Nesta revisão, discutiremos os principais métodos de análise clínica e instrumental da camada de fibras nervosas da retina e revisamos os principais achados encontrados nas afecções da via óptica anterior incluindo lesões inflamatórias, isquêmicas, tóxicas, hereditárias, compressivas e traumáticas do nervo óptico, as lesões do quiasma óptico, as do trato óptico e aquelas do corpo geniculado lateral.

Retinal nerve fiber evaluation is important in the diagnosis and management of several diseases of the anterior visual pathway. In this report we review the clinical findings and the current techonologies avalilable to analyse the retinal nerve fiber layer. We furthermore review the main findings in several disease of the anterior visual pathways including inflammatory, ischemic, toxics, hereditary, compressive and traumatic optic neuropathies as well as lesion of the optic chiasm, optic tract and lateral geniculate body.

Visual fields in neuro-ophthalmology.

Visual field assessment is important in the evaluation of lesions involving the visual pathways and should be performed at baseline and periodically in the follow-up. Standard automated perimetry has been shown to be adequate in neuro-ophthalmic practise and is now the technique of choice for a majority of practitioners. Goldman kinetic visual fields are useful for patients with severe visual and neurologic deficits and patients with peripheral visual field defects. Visual fields are useful in monitoring progression or recurrence of disease and guide treatment for conditions such as idiopathic intracranial hypertension (IIH), optic neuropathy from multiple sclerosis, pituitary adenomas, and other sellar lesions. They are used as screening tools for toxic optic neuropathy from medications such as ethambutol and vigabatrin. Visual field defects can adversely affect activities of daily living such as personal hygiene, reading, and driving and should be taken into consideration when planning rehabilitation strategies. Visual field testing must be performed in all patients with lesions of the visual pathway.

Relationship between visual field sensitivity loss and quadrantic macular thickness measured with Stratus-Optical coherence tomography in patients with chiasmal syndrome / Correlação entre defeito de campo visual e espessura macular quadrântica avaliada através da tomografia de coerência óptica em pacientes com compressão quiasmática

PURPOSE: To correlate visual field sensitivity (VFS) loss on standard automated perimetry (SAP) and quadrantic macular thickness on optical coherence tomography (OCT) in patients with permanent temporal hemianopia from chiasmal compression. METHODS: Forty eyes from 40 patients with chiasmal compression and 40 healthy eyes were submitted to standard automated perimetry and Stratus-OCT scanning. Raw data of the fast macular thickness scanning protocol were exported and macular thickness measurements were recorded and averaged for each quadrant and half of the central area. The correlation between visual field sensitivity loss and optical coherence tomography measurements was tested with Pearson's correlation coefficients and with linear regression analysis. RESULTS: A significant association was found between each macular thickness parameter and the corresponding central VF mean sensitivity. The strongest association was observed between superonasal macular thickness and the inferotemporal mean defect measured both in decibel (R=0.47; p=0.001) and in 1/Lambert (R=0.59; p<0.0001) units. CONCLUSION: Stratus-OCT-measured macular thickness was topographically related with visual field sensitivity loss in patients with temporal hemianopia from chiasmal compression. Such measurements could prove clinically useful in the diagnosis and follow-up of patients with chiasmal compression. ClinicalTrial.gov identifier number: NCT0039122.

OBJETIVO: Avaliar a correlação entre o defeito de campo visual ao exame de perimetria computadorizada e a espessura macular quadrântica ao exame de tomografia de coerência óptica (OCT) em pacientes com hemianopsia temporal permanente causada por compressão quiasmática. MÉTODOS: Quarenta olhos de 40 pacientes com compressão quiasmática e 40 olhos de 40 indivíduos controles foram submetidos aos exames de perimetria computadorizada e tomografia de coerência óptica. Dados não processados foram exportados e as medidas de espessura macular foram calculadas para cada quadrante e metade da área macular central. A correlação entre o defeito campimétrico e as medidas de espessura macular foi avaliada por coeficiente de correlação de Pearson e por análise de regressão linear. RESULTADOS: Associação significante foi encontrada entre os parâmetros de espessura macular e seus respectivos defeitos campimétricos. A correlação mais forte foi encontrada entre o parâmetro espessura macular nasal superior e o defeito campimétrico médio temporal inferior medido em decibel (R=0,47; p=0,001) e em 1/Lambert (R=0,59; p<0,0001). CONCLUSÃO: Medidas de espessura macular avaliada através da tomografia de coerência óptica foi topograficamente relacionada ao defeito campimétrico em pacientes com hemianopsia temporal por compressão quiasmática. Estas medidas podem provar a importância clínica no diagnóstico e seguimento dos pacientes com compressão quiasmática. ClinicalTrial.gov identifier number: NCT0039122.

Infraoptic Course of Both Anterior Cerebral Arteries

A 28-year-old woman was referred to our hospital with a sudden, very severe headache. Brain computed tomographic angiography showed a saccular cerebral aneurysm at the bifurcation of the left middle cerebral artery and infraoptic courses of both anterior cerebral arteries. The anterior cerebral arteries were seen to arise from the ipsilateral internal cerebral arteries at the level of the origin of the ophthalmic artery, passed underneath the ipsilateral optic nerve, and turned upward at ventral portion of the optic chiasm.

A week in neuro-ophthalmology: The Singapore experience

Objective@#To report the frequency of neuro-ophthalmologic cases seen over one working week by a senior neuro-ophthalmologist in Singapore and to determine a pattern in the incidence of neuro-ophthalmic diseases.@*Methods@#A retrospective review of 57 consecutive neuro-ophthalmologic cases seen by one senior neuro-ophthalmologist from June 14 to 18, 2010 was done. All patients underwent a complete neuro-ophthalmologic examination. Demographic data and clinical diagnoses were gathered.@*Results@#A total of 57 patients were seen. Thirty-one percent (18) of these patients were new consultations while the remaining 61% (39) were follow-up visits. Fifty-two percent were females (30) with a mean age of 53 years while 47% were males (27) with a mean age of 49 years. Nineteen cases involved disorders of the optic nerve followed by disorders of ocular motility (11), optic chiasm, visual pathways, and/or visual cortex (14). Among the cases involving the optic nerve, 5 were ischemic optic neuropathy. In respect to disorders of ocular motility, ocular myasthenia gravis (n=5) was the most common condition seen. Pituitary adenomas comprised the bulk of the disorders of the optic chiasm (4). The remaining neuro-ophthalmic cases were almost evenly distributed. A very rare case of Froin’s syndrome was also seen.@*Conclusion@#Overall, during the five-day neuro-ophthalmologic clinic, majority of cases were ischemic in nature, reminding readers that systemic diseases, such as hypertension, diabetes mellitus, hyperlipidemia, commonly manifest in the eye. Hence, better systemic control of these diseases is necessary.

Tumores intracranianos em pacientes encaminhados para estudos por tomografia de coerência óptica como portadores de glaucoma sem hipertensão ocular: relato de dois casos / Intracranial tumors in patients referred for optical coherence tomography examination as glaucoma suspects: case report

A tomografia de coerência óptica (OCT) tem se mostrado muito útil na avaliação de pacientes com glaucoma. São relatadas duas pacientes referidas com a suspeita de glaucoma sem hipertensão para avaliação por tomografia de coerência óptica que, na verdade, eram portadoras de tumores intracranianos - um cordoma de clivo no primeiro caso e um craniofaringeoma no segundo. Os achados à tomografia de coerência óptica - diminuição difusa da espessura da camada de fibras nervosas circumdiscais desproporcionalmente acentuada nos setores nasal e temporal - levantaram a suspeita de acometimento na região do quiasma e permitiram o diagnóstico destes importantes tumores intracranianos.

Optical coherence tomography (OCT) has proved to be a very valuable tool in the assessment of patients with glaucoma. In this report, intracranial tumors were discovered in two glaucoma suspects referred for diagnostic confirmation by OCT - a clivus chordoma and a craniopharyngeoma. Optical coherence tomography findings - marked asymmetrical diffuse attenuation of the peripapillary nerve fiber layer in nasal and temporal sectors - raised concerns about lesions in chiasmatic region and permitted the timely diagnosis of these intraocular tumors.

Cavernous Malformation of the Optic Chiasm : Case Report

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.

An unusual chiasmal visual defect in a patient with neuromyelitis optica: case report

PURPOSE: To report the unusual visual field finding due to a chiasmal neuritis in a 33-year-old female with the diagnosis of optic neuromyelitis optica (Devic's syndrome). METHODS: We report a case of a 33 years old female with limb paraesthesias, weakness in the legs, bowel and bladder dysfunction that was referred to the "Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo" in October 1995. Six years and four months later she had an acute visual involvement. Ophthalmologic examination, laboratory studies, magnetic resonance imaging (MRI) and a 24-2 threshold visual field in the Humphrey field analyzer were performed. RESULTS: The MRI scan showed enlargement and cavitation on the spinal cord and chiasmal involvement (thickening of the chiasm with contrast enhancement) and no demyelinating lesions in the brain, brainstem, or cerebellum. The central 24-degree threshold field examination showed an inferior visual field defect bitemporally, disclosing a chiasmal involvement. CONCLUSION: Chiasmal involvement may occur in neuromyelitis optica, probably due to a plaque within the chiasm. The authors call attention to the importance of visual field examination with particular regard to quantifying the visual impairment and follow-up of these patients.

OBJETIVO: Relatar o caso de uma mulher de 33 anos de idade, com o diagnóstico de neuromielite óptica (síndrome de Devic) acometendo o quiasma óptico que apresentou um escotoma incomum no exame de campo visual. MÉTODOS: Uma paciente do sexo feminino, portadora de parestesias nos membros inferiores, fraqueza nas pernas, disfunção da defecação e disfunção urinária, foi encaminhada para o Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo em outubro do ano de 1995. Seis anos e quatro meses mais tarde ela sofreu acometimento visual agudo. Foram realizados exame oftalmológico completo, exame de líquor, ressonância nuclear magnética e um exame de campo visual no perímetro de Humphrey. RESULTADOS: A ressonância magnética revelou espessamento e imagens de cavitações na medula espinal, assim como espessamento do quiasma óptico, acompanhado de aumento na captação do contraste. Não apareceu imagem sugestiva de processo desmielinizante no cérebro, tronco cerebral ou cerebelo. O exame 24-2 (campo visual central) demonstrou defeito bitemporal inferior, revelando assim o comprometimento do chiasma. CONCLUSÃO: Comprometimento do quiasma óptico pode ocorrer nos casos de neuromielite óptica, provavelmente devido a uma placa de desmielinização ocorrendo no quiasma. Os autores enfatizam a importância do exame de campo visual para quantificar o comprometimento das vias ópticas e acompanhar a evolução destes pacientes.

Relationship between Location and Size of Pituitary Adenoma and Visual Field Change

PURPOSE: To evaluate the relationship between the location and size of pituitary adenoma and visual field change. METHODS: Fifty-two patients were diagnosed with pituitary adenoma and underwent tumor resection at the Department of Neurosurgery in our hospital between July 1999 and July 2004. Among them, we retrospectively studied that location and size of pituitary adenoma as related to visual field changes in 29 patients who had credible perimetry results and no other ophthalmologic problems that caused visual field changes. We obtained the information about the size and location of pituitary adenoma using MRI, and performed ophthalmologic examination such as perimetry and fundus examination. RESULTS: There were no visual field changes in 18 patients. The visual field changes observed were as follows; bitemporal hemianopsia in 4 patients who had inferior involvement of optic chiasm; scotoma in one eye and temporal hemianopsia in the other eye in 2 patients who had lateral and inferior involvement; bitemporal superior quadranopsia in 2 patients who had anterior and inferior involvement; and 3 patients showed visual field changes, but they had no optic nerve involvement of pituitary adenoma. The size of adenoma was not exactly related to visual field changes. CONCLUSIONS: These results indicate that visual field changes can be influenced by the location and size of pituitary adenoma.

LINAC-Based Radiosurgery of Arteriovenous Malformation involving Visual Pathway: A Report of Two Cases / 대한뇌혈관외과학회지

The authors present two cases of arteriovenous malformation (AVM) involving the visual pathway following linear accelerator (LINAC) stereotactic radiosurgery. Both patients were treated with 18 Gy (marginal dose, 70-80% isodose line, 3 isocenter) delivered to the malformed vascular mass involving the optic tract on the right side. For both patients, however, less than 8 Gy were irradiated onto the ipsilateral optic chiasm and optic nerve, and 4.5 Gy were irradiated onto the contralateral optic nerve (20% isodose line). On the five-year follow-up MRI scan and angiogram, the AVM was totally obliterated in one patient and the AVM was markedly decreased in size in the other patient. Their visual fields were well preserved and visual acuities were even improved for both patients. We report here with on two cases of AVM involving the visual pathway that were effectively and safely treated with 18 Gy using LINAC-based radiosurgery, and we also attempt to define the safe and effective radiation dosage for the patients with AVM involving visual apparatus.