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At least 937 records · Page 52Linked to original sources
PubMed1999

Diaphragma sellae metastasis from colon carcinoma mimicking a meningioma. A case report.

We describe a rare case of metastatic intra-suprasellar adenocarcinoma from colonic cancer mimicking a meningioma of the "diaphragma sellae". Autopsy studies indicate breast and lung carcinoma to be the most frequent primary tumor metastasizing this site, particularly in patients with systemic spread. While diabetes insipidus is reported to be one of the commonest symptoms in these cases, the only clinical manifestation of the tumor in our patient was a bitemporal hemianopia, while the primary tumor remained asymptomatic. In the available literature are reported only two pituitary metastasis from operated colon carcinoma. In both cases the diagnosis of the colon cancer preceded the pituitary operation. The clinico-pathological and neuroradiological aspects of this unusual lesion are analyzed in the light of the relevant literature on the topic focusing on recent MRI acquisitions.

Adenocarcinoma↗
PubMed2000

Cortical visual impairment in children with infantile spasms.

BACKGROUND: Infantile spasms are often associated with cortical visual impairment. METHOD: We report a series of 10 patients with infantile spasms, hypsarrhythmic electroencephalograms, and developmental delay, (ie, West syndrome), who presented with severe visual inattention despite a normal ocular examination. RESULTS: At follow-up (14 months to 6 years), 5 patients (50%) had no improvement in their visual behaviour. Although some degree of improvement was observed in the others, their visual function remained abnormal. All patients had moderate or severe mental retardation. CONCLUSIONS: The clinical features of West syndrome are reviewed, and the cause of the associated cortical visual impairment is discussed. Cortical visual impairment with infantile spasms is an important association, which pediatric ophthalmologists should recognize.

Diagnosis, Differential↗
PubMed2000

Pneumosinus dilatans of the sphenoid sinus presenting with visual loss.

OBJECTIVE: To report 3 cases of pneumosinus dilatans of the sphenoid sinus associated with visual loss. MATERIALS AND METHODS: Retrospective case series describing history of visual loss, visual examination, visual field deficits, and radiologic imaging. RESULTS: Three patients developed visual loss associated with pneumosinus dilatans of the sphenoid sinus. CONCLUSIONS: Pneumosinus dilatans of the sphenoid sinus is a rare disorder that should be considered in patients presenting with unexplained visual loss.

Adult↗
PubMed2001

Surveying the seen: 100 years of British vision.

Perceptual phenomena and their interpretations have fashioned the course of psychology. This article surveys how theories of visual perception and methodologies have developed during the lifetime of the British Psychological Society. The experimental study of vision was instigated by British natural philosophers in the early nineteenth century but this impetus was not maintained thereafter. Not until the 1930s and 1940s did research on perception resume in earnest within British universities. The adoption of concepts (such as schema) potentially grounded in neural organization, particularly by Bartlett and Craik, accelerated experimental, theoretical and applied vision research. From mid-century the influence of information processing models of perception became increasingly dominant, and they were often integrated with the rapidly expanding understanding of neurophysiological underpinnings. The epitome of these developments was Marr's model of vision which, in our view, marked the start of the modern era of vision research. Computers have transformed the nature of stimulus control and response measurement in perceptual experiments. More naturalistic stimuli can be presented and manipulated, and complex behavioural responses, such as patterns of eye movements, fractionated. Non-invasive recording of brain activity to visual stimulation has similarly been transformed with a variety of methods for imaging brain activity. Neuroimaging has been applied to localizing perceptual and cognitive functions and in studying patients with known deficits in visual recognition. However, the eagerness with which the computer has been adopted by perceptual psychologists is likely to be tempered by a growing awareness of the differences between viewing scenes and simulations of them.

Brain↗
PubMed2001

[Malignant fibrous histiocytoma (fibrohistiocytoma malignum) localized intracranially].

Primary intracranial malignant fibrous histiocytoma (MFH) is an extremely rare occurrence, however this kind of neoplasm is observed among the sarcomas. The aim of this report is to present a case of malignant fibrous histiocytoma in a 22 years-old woman. The control examination performed five years after operation revealed only mild exophthalmus and visual disturbances as presented before surgery.

Adult↗
PubMed2001

Transsphenoidal approaches for the extracapsular resection of midline suprasellar and anterior cranial base lesions.

OBJECTIVE: The transsphenoidal approach is an effective method for treating tumors contained within the sella or extending into the suprasellar cistern. The technique of tumor dissection is predicated on preservation of the integrity of the diaphragma, i.e., intracapsular removal. Gross total extracapsular dissection may, however, be accomplished either by using a standard approach to the pituitary fossa or by extending the exposure to include removal of a portion of the planum sphenoidale and division of the superior intercavernous sinus. METHODS: Included in this series were 14 patients with parasellar or sellar tumors with extension into the anterior fossa and/or suprasellar cistern. For 4 of 14 patients (29%), extracapsular access was gained by broaching the tumor capsule from within the pituitary fossa. For the remaining 10 of 14 patients (71%), the dura of the floor of the sella and the planum sphenoidale was exposed, using neuronavigation to verify the limits of bony dissection; extracapsular tumor resection was performed using the operating microscope and endoscopy as indicated. The dural defect was repaired with abdominal fat, the sellar floor and planum sphenoidale were reconstructed, and in selected cases a lumbar drain was placed. RESULTS: Seven of 14 tumors (50%) were craniopharyngiomas, 3 of 14 (21%) were pituitary adenomas, and 2 of 14 (14%) were meningiomas. There was one case of lymphocytic hypophysitis and one yolk sac tumor. Gross total resection was possible in 11 of 14 cases (79%). Immediate postoperative visual function worsened in 2 of 14 cases (14%), improved in 3 of 14 cases (21%), and was stable in the remainder of cases. Postoperatively, 2 of 14 patients (14%) developed bacterial meningitis. Overt postoperative cerebrospinal fluid rhinorrhea was not observed. CONCLUSION: Gross total extracapsular resection of midline suprasellar tumors via a transsphenoidal approach is possible but is associated with a higher risk of complications than is standard transsphenoidal surgery.

Adult↗
PubMedDate not supplied

[Reversible posterior leukoencephalopathy, severe hypertension, and cocaine abuse].

Reversible posterior leukoencephalopathy syndrome is a brain disorder characterized by headache, nausea, vomiting, visual disturbance, depressed level of consciousness, convulsions and occasionally focal neurologic deficits. It is commonly associated with malignant hypertension, toxemia of pregnancy or the use of immunosuppressive agents. Early diagnosis and specific treatment is essential. We report a case of reversible posterior leukoencephalopathy in the context of a hypertensive crisis in an habitual cocaine sniffer. Reversible posterior leukoencephalopathy must be suspected in every patient with hypertensive crisis and compatible clinic manifestation. Neuroimaging studies show characteristic features which confirm the diagnosis.

Administration, Inhalation↗
PubMed2001

Strabismus due to flap tear of a rectus muscle.

PURPOSE: To present a previously unreported avulsion-type injury of the rectus muscle, usually the inferior rectus, and detail its diagnosis and operative repair. METHODS: Thirty-five patients underwent repair of flap tears of 42 rectus muscles. The muscle abnormality was often subtle, with narrowing or thinning of the remaining attached global layer of muscle. The detached flap of external (orbital) muscle was found embedded in surrounding orbital fat and connective tissue. Retrieval and repair were performed in each case. RESULTS: Fourteen patients had orbital fractures, 7 had blunt trauma with no fracture, and 9 had suspected trauma but did not undergo computed tomographic scan. Five patients experienced this phenomenon following retinal detachment repair. Diagnostically, the predominant motility defect in 25 muscles was limitation toward the field of action of the muscle, presumably as a result of a tether created by the torn flap. These tethers simulated muscle palsy. Seventeen muscles were restricted away from their field of action, simulating entrapment. The direction taken by the flap during healing determined the resultant strabismus pattern. All patients presenting with gaze limitation toward an orbital fracture had flap tears. The worst results following flap tear repair were seen in patients who had undergone orbital fracture repair before presentation, patients who had undergone previous attempts at strabismus repair, and patients who experienced the longest intervals between the precipitating event and the repair. The best results were obtained in patients who underwent simultaneous fracture and strabismus repair or early strabismus repair alone. CONCLUSIONS: Avulsion-type flap tears of the extraocular muscles are a common cause of strabismus after trauma, and after repair for retinal detachment. Early repair produces the best results, but improvement is possible despite long delay.

Adolescent↗
PubMed2001

Surveying the seen: 100 years of British vision.

Perceptual phenomena and their interpretations have fashioned the course of psychology. This article surveys how theories of visual perception and methodologies have developed during the lifetime of the British Psychological Society. The experimental study of vision was instigated by British natural philosophers in the early nineteenth century but this impetus was not maintained thereafter. Not until the 1930s and 1940s did research on perception resume in earnest within British universities. The adoption of concepts (such as schema) potentially grounded in neural organization, particularly by Bartlett and Craik, accelerated experimental, theoretical and applied vision research. From mid-century the influence of information processing models of perception became increasingly dominant, and they were often integrated with the rapidly expanding understanding of neurophysiological underpinnings. The epitome of these developments was Marr's model of vision which, in our view, marked the start of the modern era of vision research. Computers have transformed the nature of stimulus control and response measurement in perceptual experiments. More naturalistic stimuli can be presented and manipulated, and complex behavioural responses, such as patterns of eye movements, fractionated. Non-invasive recording of brain activity to visual stimulation has similarly been transformed with a variety of methods for imaging brain activity. Neuroimaging has been applied to localizing perceptual and cognitive functions and in studying patients with known deficits in visual recognition. However, the eagerness with which the computer has been adopted by perceptual psychologists is likely to be tempered by a growing awareness of the differences between viewing scenes and simulations of them.

Journal Article↗
PubMed2002

The neurology of eclampsia : some observations.

Nineteen patients admitted with diagnosis of eclampsia in a large general hospital between 1996 - 1999, were analyzed. Eight patients were referred to neurologists for assessment and management. All these patients had recurrent generalized seizures. Five patients developed visual disturbance. Neuroimaging (CT and/or MRI) revealed symmetrical occipital lesions in all. One patient had a large pontine lesion. Seizure control was achieved in all with intravenous phenytoin. All patients recovered fully without any residual neurological deficit and their radiological brain lesions resolved completely, in all except one case. The neurological manifestations and neuroimaging features in cases of eclampsia have been reviewed. A brief note on the pathogenesis of the cerebral lesions is included and the controversial aspect of seizure control in eclampsia highlighted.

Adult↗
PubMed2002

Correlation between CT scan and automated perimetry in supratentorial tumors.

An attempt was made to correlate various types of visual field defects on automated perimetry with the findings of computed tomography in 44 patients of supratentorial tumors. All the patients above the age of 10 years were subjected to complete neurological examination including investigations like plain X-rays and CT scan, however, MRI and angiography were performed wherever indicated. Ocular examination particularly pertaining to neuro-ophthalmological profile was carried out with special emphasis on automated perimetry on Humphrey field analyser. The results indicated that automated perimetry was capable of reliably detecting and quantitating the visual field defects and thus established the location of the tumor in 72% patients when compared to CT scan. Hence, any patient with neuro-ophthalmic features should be subjected to automated perimetry for early diagnosis and probable location of intracranial space occupying lesion affecting visual pathways.

Adult↗
PubMedDate not supplied

[Neuro-ophthalmological symptoms in patients with para-clinoid aneurysms].

Neuroophthalmological symptoms in patients with large and giant paraclinoid aneurysms is presented, based on analysis of case histories, examination of visual functions, and evaluation of ophthalmoscopic picture. Variants of paraclinoid aneurysm location with respect to optic tract structures and the visual function are discussed. Methods of modulating the peripheral and central neurons of the optic tract are described.

Adolescent↗
PubMed2003

[Postoperative visual improvement in spheno-orbital meningioma: a case report].

A 59-year-old woman complained of right eye proptosis and visual impairment (20/100) lasting 2 months. CT and MRI scans disclosed a right spheno-orbital meningioma ranging over the optic foramen and cavernous sinus. Histopathology revealed transitional meningioma. Visual acuity (20/25), visual field, and proptosis were improved after surgery at the time of the ophthalmologic examination 6 months later. We present an additional case and review the available literature concerning postoperative visual outcome.

Cavernous Sinus↗