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At least 883 records · Page 49Linked to original sources
PubMed1987

Looking but not seeing: attention, perception, and eye movements in simultanagnosia.

We studied three subjects who reported the apparent "disappearance" of stationary objects from direct view. They had simultanagnosia caused by CT-verified bilateral superior occipital lobe lesions. They had no abnormalities of visual acuity or fields to explain their defect. EOG with computer analysis showed intact motility and scanning. Most important, the subjects reported intermittent disappearance of a light target during EOG-verified fixation--ie, they were looking but not seeing. Results indicate that attention mechanisms that permit sustained awareness of visual targets depend on the superior visual association cortices and are relatively separate from mechanisms that shift gaze and drive visual search.

Aged↗
PubMed1987

The role of nuclear magnetic resonance imaging in the diagnosis of MS in childhood.

MS in the pediatric age group is a rare condition, often diagnosed after a considerable delay. Nuclear magnetic resonance imaging (NMR) has proven to be the single most useful diagnostic modality in adult MS patients. We present three patients with childhood MS. NMR demonstrated multiple white matter lesions in the supratentorial and posterior fossa regions consistent with those lesions described by NMR in adults. This report suggests that NMR is a valuable diagnostic procedure in children as well as adults.

Brain↗
PubMed1988

Optic neuritis in the elderly: prognosis for visual recovery and long-term follow-up.

We evaluated 14 patients with idiopathic optic neuritis, 50 years of age or older, within 1 month of symptomatic onset from 1980 through 1985. We obtained follow-up information from case records an average of 13 months after initial examination and from telephone interviews an average of 57 months after initial evaluation. Four patients were men and ten were women. Visual loss was monocular in ten cases and binocular in four. Only one of 18 affected eyes initially had an acuity of 20/30 or better. Eleven eyes recovered acuities of 20/30 or better. There was no apparent benefit to those patients treated with corticosteroid agents. Six patients (43%) developed other neurologic sequelae an average of 16 months later; four (28%) had a second bout of optic neuritis and three (21%) developed clinically definite MS. Optic neuritis in the elderly behaves similarly to that disorder in younger age groups.

Aged↗
PubMed1988

Congenital quadrantanopia with occipital lobe ganglioglioma.

A 24-year-old man with recent-onset seizures was found to have an occipital lobe ganglioglioma with homonymous quadrantanopia and trans-synaptic atrophy of retinal nerve fibers. This association indicates that gangliogliomas may arise during neural development and exist for many years before onset of symptoms.

Adult↗
PubMed1989

Hemispatial visual inattention masquerading as hemianopia.

The defect occurring when a patient fails to report a visual stimulus presented in a visual half-field may be attributed to hemianopia (deafferentation) caused by a geniculocalcarine lesion. However, failure to report a stimulus presented in a visual field may also be caused by hemispatial visual inattention. We report a patient with right thalamic and temporo-occipital lesions who had a left visual field defect when her eyes were directed either straight ahead (midsagittal plane) or toward left hemispace. However, this visual field defect abated when her eyes were directed to right hemispace, suggesting that the patient had hemispatial visual inattention rather than hemianopia.

Aged↗
PubMed1979

Trans-sphenoidal removal of a Rathke's cleft cyst.

Symptomatic Rathke's cleft cysts are uncommon. We present a case with suprasellar extension manifested by hypopituitarism and visual disturbances. The treatment was trans-sphenoidal evacuation and partial removal of the capsule. We suggest that the trans-sphenoidal approach to these lesions is usually adequate and that radical removal of the capsule is not necessary.

Confusion↗
PubMed1979

Checkerboard visual evoked response in evaluation and management of pituitary tumors.

As a routine part of the evaluation of patients with pituitary tumor, visual evoked responses (VERs) to checkerboard pattern reversal were recorded from 83 patients with tomographically documented pituitary tumor. VER tests were correlated with examinations of visual acuity, color perception, and visual fields and with computerized tomographic scan evidence of suprasellar extension of the tumor. The purpose of the VER recording was to determine the presence of visual system compression by the tumor and thus contribute to the decision of whether surgery was necessary. Each of the patients who had suprasellar extension of the tumor sufficient to produce a visual field abnormality also had an abnormal VER. In addition, some patients with suprasellar extension had normal visual fields but abnormal visual evoked responses. Thus, the VER provided earlier evidence of suprasellar extension causing visual system compromise than did conventional visual tests.

Adenoma, Chromophobe↗
PubMed1980

Benign intracranial hypertension without papilledema: role of 24-hour cerebrospinal fluid pressure monitoring in diagnosis and management.

Nine patients whose history suggested increased intracranial pressure (ICP), but whose funduscopic examination did not reveal papilledema, are described. Cerebrospinal fluid monitoring in seven of the cases showed abnormal pressure waves ranging from 22 to 40 mm Hg. The findings of computed tomography and isotope cisternography and the response to therapy supported the clinical diagnosis of benign intracranial hypertension (BIH). Fluorescein angiography, which was performed in five cases, was normal. None of the patients had enlargement of the blind spot; all had normal intraocular pressure. The clinical spectrum of BIH may need to be enlarged to include cases of increased ICP without clinically evident papilledema. (Neurosurgery, 7: 326-336, 1980).

Adolescent↗
PubMed1985

Visual recovery after transsphenoidal removal of pituitary adenomas.

We reviewed the records of 100 consecutive patients with histologically verified pituitary adenomas who underwent transsphenoidal decompression of the optic nerves and chiasm. The patients' ages ranged from 18 to 80 years, with a median of 52 years. Preoperatively, all patients had objective signs of visual acuity or field defects. Postoperatively, visual acuity was normal or improved in 79% of the eyes and the visual fields were normal or improved in 74%. The visual outcome (for both acuity and fields) was better in younger patients and those with a shorter duration of symptoms. Patients with lesser degrees of preoperative visual acuity compromise had better postoperative visual acuity outcome. However, the severity of preoperative visual field defects did not seem to predict postoperative field outcome, and even patients with severe preoperative field defects often had striking postoperative improvement. Patients who had undergone prior operation were less likely to have either visual acuity or visual field improvement after reoperation. Postoperative deterioration in visual acuity was noted in only 5 patients (6 eyes). Complications were few. There were 4 instances of cerebrospinal fluid rhinorrhea, but only 2 patients needed operative repair. There was no instance of permanent diabetes insipidus, although 17 patients developed transient diabetes insipidus. In most cases, visual improvement was sustained. The average duration of follow-up was 26 months. Three patients required a subsequent operation to correct visual loss in the immediate postoperative period, but only 1 patient has undergone late operation for recurrence of tumor. There was no operative mortality.

Adenoma↗
PubMed1986

Metamorphopsia and permanent cortical blindness after a posterior fossa tumor.

A case of posterior fossa tumor associated with supratentorial symptoms is presented. The pattern of symptoms that developed after operation follow the description of metamorphospsia. The condition progressed to permanent cortical blindness. Tumoral vasospasm is suggested as a possible etiological mechanism for the clinical picture.

Blindness↗
PubMed1987

Visual hallucinations associated with pituitary adenoma.

Visual hallucinations were the presenting symptom in three patients with pituitary adenoma. One patient reported only simple unformed hallucinations, which are a well-documented phenomenon occurring in lesions compressing the optic nerves and chiasm. The other two patients, however, experienced complex formed visual hallucinations believed to be of the release type. No evidence of seizure activity responsible for the hallucinations was found; the mechanism producing them is discussed with correlation to operative findings and electrophysiological studies.

Adenoma↗
PubMed1987

Primary myxoma in the pituitary fossa: case report.

A case of primary myxoma in the pituitary fossa is described. The tumor presented as an intrasellar and suprasellar mass and was successfully removed during a transsphenoidal operation. It was verified as a myxoma by histopathological studies, and there was no evidence that it was a metastasis. This is thought to be the first report of this tumor occurring in the pituitary fossa.

Adult↗
PubMed1992

Radiologic characteristics and results of surgical management of Rathke's cysts in 43 patients.

Although Rathke's cysts are a relatively common autopsy finding, rarely have they been reported as a clinical entity. Because of recent improvements in neuroradiological imaging, cystic intrasellar and suprasellar lesions are discovered often, leading to questions about proper management. Against this background, we reviewed the data from 43 patients with Rathke's cysts treated by one neurosurgeon over a 13-year period, and present the results here. The 43 patients had a mean age of 34 years, and 77% were female. Headache was the most common symptom, followed by galactorrhea, visual field loss, and hypopituitarism. Computed tomographic (CT) scans were reviewed in 20 cases, magnetic resonance (MR) images were reviewed in 15, and both CT and MR studies were reviewed in 5 cases. Although all Rathke's cysts were discrete and well-defined by both CT and MR imaging, the diversity of locations, CT attenuations, and MR signal intensity make it difficult to establish the diagnosis by radiological criteria. Forty patients underwent transsphenoidal surgery and three underwent craniotomy. There was one recurrence at 25 months requiring a second operation, and the mean follow-up period was 62 months. Seven patients had persistent headaches. For symptomatic lesions suspected to be Rathke's cysts, the recommended treatment is simple drainage of the cyst with biopsy of the wall, when this can be done safely. Follow-up imaging should be minimal for asymptomatic patients, and radiation therapy is not indicated.

Adolescent↗
PubMed1994

Surgical management of orbital cavernous angiomas: prognosis for visual function after removal.

The authors report the outcome of surgical treatment in a group of 25 patients with cavernous angioma of the orbital cavity. In the majority of cases, good esthetic results were appreciable within a few days of surgery. However, the onset or deterioration of preexisting visual deficits, in spite of the complete preservation of the optic nerve in a third of these patients, draws attention to the need for accurate surgical timing.

Adult↗
PubMed2003

Meningiomas involving the optic nerve: technical aspects and outcomes for a series of 50 patients.

OBJECTIVE: Surgical strategies and results for 50 patients with meningiomas involving the optic nerves are discussed and evaluated. Factors affecting the degree of resection and patient outcomes are presented. We emphasize our surgical techniques for resection of these tumors and we discuss the advantages of different approaches, depending on the relationship of the tumor to the optic nerves. METHODS: Data for 50 patients with meningiomas involving the optic nerves who were surgically treated between 1991 and 2002 were reviewed, by using patient files, operative notes, and pre- and postoperative imaging and ophthalmological examination findings. RESULTS: Thirty-one female patients and 19 male patients, with a mean age of 53 years, were treated. Thirty-one patients (62%) underwent complete tumor removal (Simpson Grade 1 or 2), and 19 patients underwent subtotal removal (Grade 4). Factors affecting the grade of resection were tumor size (P = 0.01), location (P = 0.007), and internal carotid artery encasement (P = 0.019). Patients who underwent Grade 1 or 2 resection exhibited a mean tumor size of 3.0 cm, and patients who underwent Grade 4 resection exhibited a mean tumor size of 4.1 cm. Only three patients had residual tumor on the optic nerve; all others had tumor in the cavernous sinus or at the orbital apex or exhibited vascular involvement. Visual outcomes were influenced predominantly by tumor size, preoperative visual function, and optic nerve encasement. CONCLUSION: Meningiomas that involve the optic nerves require special considerations and surgical techniques. Early decompression of the optic nerve within the bony canal allows identification and separation of the tumor from the nerve, permitting removal of the tumor from this area with minimal manipulation of the optic nerve.

Adult↗
PubMed1996

Intracranial arterial calcification and ectasia in visual failure.

Calcification of the major intracranial arteries is frequently observed on computed tomography (CT), particularly in the carotid siphon, and has been implicated as a causative factor in low tension glaucoma. Ectasia of the carotid siphon has also been postulated as a possible cause of compressive optic neuropathy. 153 patients, in whom high resolution CT of the orbits and parasellar region had been performed for suspected anterior visual pathway pathology, were retrospectively reviewed. The presence and severity of calcification and ectasia of the major intracranial arteries was recorded. There was a high occurrence of carotid siphon calcification, increasing with age, and independent of sex or race. Calcification was very rare in anterior cerebral, middle cerebral and basilar arteries in all age groups. The amount and degree of ectasia also increased with advancing age, and was more frequently observed in carotid and basilar than anterior and middle cerebral arteries. There was no correlation between the degree of calcification or ectasia and ophthalmological or neurological deficit.

Adolescent↗