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At least 721 records · Page 40Linked to original sources
PubMed1996

Rhabdomyosarcoma presumed metastatic to the orbit.

BACKGROUND: Orbital metastasis from rhabdomyosarcoma is a rare disorder with a poor prognosis for long-term survival. Only one other detailed account of this disorder has appeared in the ophthalmic literature. METHODS: The authors report the clinical features of four patients with presumed orbital metastasis from alveolar and embryonal rhabdomyosarcoma. RESULTS: The most common ophthalmic manifestations of orbital metastasis from rhabdomyosarcoma in these patients included proptosis, reduced visual acuity, orbital pain, and motility disorders. Computed tomography documented orbital masses in all of the patients. In those patients with a primary tumor of the maxillary sinus, there was no evidence of direct extension into the orbit. Despite combination chemotherapy and radiation, all four patients died of their illness within 6 months of orbital metastasis. CONCLUSIONS: Although uncommon, rhabdomyosarcoma should be considered in the differential diagnosis of metastatic tumors to the orbit in children and adults. Despite the poor prognosis, prompt diagnosis and palliative radiotherapy may improve the quality of life for these patients with terminal disease.

Adolescent↗
PubMed1998

The cupped disc. Who needs neuroimaging?

OBJECTIVE: To determine the incidence of positive neuroradiologic studies in consecutive patients with glaucoma associated with normal intraocular pressure and to compare the psychophysical and clinical characteristics of these eyes with eyes with disc cupping associated with intracranial masses. DESIGN: Retrospective case-controlled study. PARTICIPANTS: Fifty-two eyes of 29 patients with glaucoma associated with normal intraocular pressure and 44 eyes of 28 control patients with compressive lesions were reviewed. INTERVENTION: The medical records of consecutive glaucoma patients with normal intraocular pressure who underwent brain magnetic resonance imaging or computed tomography scanning as part of a diagnostic evaluation between January 1, 1985, and July 1, 1995, were reviewed. A masked reading of optic nerve photographs and visual fields was performed by one observer. A similar analysis was performed on a control group of consecutive patients with nonglaucomatous optic nerve cupping with known intracranial mass lesions. MAIN OUTCOME MEASURES: The neuroradiologic findings, clinical characteristics, optic nerve head appearance, and patterns of visual field loss were compared between groups. RESULTS: None of the patients diagnosed with glaucoma had neuroradiologic evidence of a mass lesion involving the anterior visual pathway. Compared to control subjects, patients with glaucoma were older (P = 0.0001), had better visual acuity (P = 0.002), greater vertical loss of neuroretinal rim tissue (P = 0.0001), more frequent optic disc hemorrhages (P = 0.01), less neuroretinal rim pallor (P = 0.0001), and more nerve fiber bundle visual field defects aligned at the horizontal midline (P = 0.0001). Visual acuity less than 20/40, vertically aligned visual field defects, optic nerve pallor in excess of cupping, and age younger than 50 years were 77%, 81%, 90%, and 93% specific for nonglaucomatous cupping associated with compressive lesions, respectively. CONCLUSIONS: Anterior visual pathway compression is an uncommon finding in the neuroradiologic evaluation of patients with a presumptive diagnosis of normal-tension glaucoma. Younger age, lower levels of visual acuity, vertically aligned visual field defects, and neuroretinal rim pallor may increase the likelihood of identifying an intracranial mass lesion.

Adolescent↗
PubMed1992

A visual suppression test using post-rotatory nystagmus.

The visual suppression test is one method for examining the function of visual fixation and visual influence on vestibular nystagmus. In this study the visual suppression test using post-rotatory nystagmus was investigated in 65 normal subjects and 142 clinical cases with cerebellar lesions. In 65 normal subjects the mean +/- standard deviation of visual suppression of the slow phase velocity on post-rotatory nystagmus was 69 +/- 11%. As to the stimulation for visual suppression test, the post-rotatory method using rotatory stimulation is milder than caloric stimulation. This method is far simpler to analyze than the visual suppression test using pendular rotatory nystagmus and other vestibulo-ocular reflex tests. In the 142 patients with cerebellar lesions, reduced or abolished visual suppression on post-rotatory nystagmus was seen in 89 patients with radiologically confirmed disturbances in the vestibulo-cerebellum. And this method could identify the lesion side in the cerebellum. These results showed a correlation between the visual suppression test using post-rotatory nystagmus and one using caloric nystagmus in 65 normal subjects and 142 clinical cases with cerebellar lesions.

Caloric Tests↗
PubMed2000

A sighting of orbital pseudotumor.

A 39-year-old woman developed bilateral proptosis, photophobia, and pain with extraocular movements over the course of 5 days. Her findings initially were ocular pain and photophobia which progressed to periorbital edema and nasal discharge ultimately resulting in proptosis with vertical globe displacement and decreased visual acuity. She was diagnosed with corneal abrasion and sinusitis respectively during two initial emergency department visits. On her third visit to the emergency department within 4 days, she developed acute visual deficits. The patient was subsequently diagnosed with orbital pseudotumor after computed tomography scan revealed inflammation of orbital structures bilaterally.

Adult↗
PubMed1998

Clinical and radiologic evaluation of optic pathway lesions.

The clinical evaluation can often suggest the level of a visual pathway lesion; however, several different types of pathological processes, can produce the same visual field deficit. Imaging evaluation with CT and/or MRI can help to localize and characterize these diverse types of pathology. A radiological differential diagnosis can then be suggested which, in turn, facilitates patient management. In certain instances, the specific cause of a visual field defect can be identified with the radiological evaluation.

Brain Diseases↗
PubMed1998

Imaging of sella and parasellar disease.

The sella and parasellar region may be affected by a variety of disease states. Diseases of this region often result in visual disturbances because of the proximity of the sella to the optic pathways and cranial nerves. Knowledge of the pathological conditions affecting the sella and surrounding structures is important for the orbital imager.

Aneurysm↗
PubMed2000

Compressive optic nerve atrophy resulting from a distorted internal carotid artery.

An 18-month-old female with right compressive optic nerve atrophy caused by an ipsilateral distorted internal carotid artery is reported. She was referred to an ophthalmologist at 8 months of age with the complaint of unilateral visual loss. Neuroimaging studies should contribute markedly to the determination of the causes of visual problems in young children.

Carotid Artery, Internal↗
PubMed1994

Preoperative difficulties in differentiating intraosseous meningiomas and fibrous dysplasia around the orbital apex.

Intraosseous meningiomas and fibrous dysplasia affecting the roof and apex of the bony orbit may be successfully treated using craniofacial techniques. Although both are usually benign conditions, meningiomas require complete excision to prevent recurrence whereas symptomatic and cosmetic correction of fibrous dysplasia may be achieved with partial removal only in the absence of progressive disease. Differentiating the two conditions is therefore important. Errors in diagnosis due to an excessive reliance on diagnostic imaging have occurred on three occasions in this series of 25 patients. This review evaluates the clinical and investigational features that are most helpful in differentiating the two conditions.

Adolescent↗
PubMed2003

[Pituitary apoplexy].

Pituitary apoplexy is an infrequent complication of pituitary adenomas, caused by hemorrhagic or ischemic infarction in the tumor, with typical clinical presentation: severe headache of sudden onset, visual disturbances, sleep tendency or comma. Along the last ten years we have treated eight patients with pituitary apoplexy. The diagnostic was clinically established in all of them. Seven cases complained of severe headache and vomiting. Eight patients reported visual disturbances. In one case low level of consciousness and meningeal irritation were the only findings. In six cases the apoplexy was the first pituitary adenoma manifestation. MRI and CT studies demonstrated the pituitary stroke in seven patients. Surgical trans-sphenoidal decompression was performed in seven patients, requiring urgent management in only one case. All patients experienced a marked visual improvement, but there was no amelioration of endocrine preoperative disturbances in any case. We conclude that quick diagnosis, early onset of hormonal therapy and urgent or delayed trans-sphenoidal surgery, depending on clinical manifestations, constitute the principies of the appropriate treatment of pituitary apoplexy.

Adenoma↗
PubMed2000

Visual target detection paradigm for the study of selective attention.

The current protocol can be used to examine selective attention. It has been used to acquire behavioral performance data in neurologically healthy normal control subjects and schizophrenic patients. A modified version, also described here, has been used to acquire functional neuroimaging data in normal subjects using positron emission tomography. Subject response accuracy and reaction times are recorded while subjects detect visual stimuli in either hemifield (left vs. right of a fixation point) or along the vertical meridian (above or below fixation). The lateralized presentation of stimuli permits the study of hemispheric specialization for selective attentional processes. Attentional load is manipulated by presenting larger-sized target stimuli alone (i.e., the letter 'O') or smaller-sized target stimuli surrounded by flanking letters. This protocol report includes a description of subject exclusion criteria, procedural details, relevant experimental conditions and variables, suggestions for data analysis, expected results, and a discussion of the protocol's significance for attentional research along with suggestions for future research.

Attention↗
PubMed1990

Visual dysfunction: abnormal sign of benign sphenoethmoidal lesions.

Isolated visual dysfunction with or without proptosis is rarely described as a sign of benign sphenoethmoidal lesions. Five patients with benign swelling of the sino-orbital region and related visual defects are reported. Cases include one patient with fibrous dysplasia, two patients with mucocoeles and two patients suffering from aspergillosis of the sinuses. A review of the literature and discussion of the cases is presented.

Adolescent↗
PubMed1998

Delayed massive epistaxis due to traumatic intracavernous carotid artery pseudoaneurysm.

Recurrent epistaxes after head injury may rarely be due to a traumatic intracavernous carotid artery pseudoaneurysm. The head injury is usually associated with fracture of the skull base and the epistaxes are severe with the first episode generally occurring one to three months after the initial trauma. We present a case which illustrates the role of high resolution computed tomography (CT) scanning and also magnetic resonance angiography (MRA) in achieving the diagnosis.

Adult↗
PubMed1986

Unusual vascular events in the territory of the posterior cerebral artery.

There is an unusual type of vascular episode in the territory of the posterior cerebral artery which remains relatively unknown. Ten cases are presented in which a posterior cerebral artery deficit developed suddenly in dramatic fashion with headache, visual symptoms, sensory and motor deficits and signs of third nerve involvement. Nine of the patients were female and one was male. Seven were under the age of 33. In all instances there was a permanent neurologic sequela, usually a hemianopia. A similar case was described in 1901. The nature of the underlying process remains obscure, but the evidence favors accompanied migraine in which a particularly severe attack results in permanent damage. The term "catastrophic migraine" is suggested.

Adolescent↗