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At least 649 records · Page 36Linked to original sources
PubMed1986

The anatomy of unilateral neglect after right-hemisphere stroke lesions. A clinical/CT-scan correlation study in man.

The anatomical correlates of extrapersonal visual neglect were investigated in 110 right-handed stroke patients with lesions confined to the right hemisphere. Neglect is much more frequently associated with retrorolandic damage, as compared with frontal lesions. The inferior parietal lobule appears to be the area most frequently involved in patients with cortical lesions showing signs of neglect. When the cerebral lesion is confined to deep structures, neglect occurs much more frequently when grey nuclei such as the thalamus and the basal ganglia are damaged; a remarkable number of negative cases were, however, found. Conversely, lesions limited to the subcortical white matter are rarely associated with neglect. The relevance of these results to anatomophysiological models of directed attention and neglect is discussed.

Adult↗
PubMed1991

Impaired metabolic activation in Alzheimer's disease: a PET study during continuous visual recognition.

Regional cerebral metabolic rate of glucose (rCMRGl) was studied in 21 patients with probable Alzheimer's disease (AD) and nine age-matched normal controls by positron emission tomography (PET) of 2(18F)-fluoro-deoxy-D-glucose (FDG) at rest and during stimulation with a continuous visual recognition task. While global metabolism at rest was comparable in both groups, rCMRGl in the temporo-parietal junction area, the mid-temporal and the frontal cortex was typically decreased in the AD patients. The continuous visual recognition task adapted to the individual performance capacity increased the global metabolic rate in the controls by 21 +/- 18%, while in the AD patients the metabolic change (5.7 +/- 11.1%) during activation was significantly weaker (P = 0.023). Due to the tasks chosen the activation of rCMRGl in both groups was most prominent in the visual cortex and the temporo-parietal association areas, although the recognition task additionally involved widespread brain structures with varying rCMRGl. A significant correlation was found between rCMRGl in areas usually severely affected by AD pathology, e.g. the temporo-parietal cortex, and GDS scores, and became stronger during metabolic activation. Neither at rest nor during stimulation was there a relationship between the rCMRGl of structures usually less involved in AD, e.g. the sensorimotor cortex, and the severity of dementia as assessed by the global deterioration scale (GDS). From these results it can be concluded that metabolic rate at rest reflects the extent of morphologic damage, while PET studies during activation indicate the brain's reserve capacity to respond to functional tasks. Since metabolism in AD patients during activation is more severely impaired than at rest, PET studies during functional tests could help in the selection of patients with a potential to benefit from therapeutic intervention.

Alzheimer Disease↗
PubMed1995

Generating visual mental images: deficit after brain damage.

This is the first non-retrospective neuropsychological group study using a componential task analysis for the study of imagery. Seventy unilaterally brain damaged patients were tested on a series of tasks with the intent of isolating genuine deficits of the image generation process. The main finding is that the image generation seems to be more frequently disturbed after a left posterior damage. Suggestions are provided for further investigations.

Adult↗
PubMedDate not supplied

Diagnosis of the empty sella with intrathecal metrizamide computed tomography.

The empty sella syndrome can be diagnosed with high resolution computed tomography. The addition of intrathecal metrizamide defines the degree of extension of the subarachnoid space into the sella turcica, demonstrates the relationship of surrounding structures, and differentiates the empty sella from other isodense or hypodense intrasellar lesions. Photographs from a case of primary empty sella demonstrate the details of anatomy seen with metrizamide computed tomography combined with sagittal reconstruction.

Adult↗
PubMedDate not supplied

Visual loss "at stool".

A 25-year-old white man presented with a history of loss of consciousness and visual loss associated with a Valsalva maneuver. Examination revealed a visual acuity of "no light perception" in his right eye with a flat visual evoked potential. The patient was subsequently found to have a giant aneurysm of the anterior communicating artery which was treated by direct clipping via a transfrontal craniotomy. The patient slowly recovered good visual function in his right eye.

Adult↗
PubMedDate not supplied

A pituitary adenoma with dilated ventricles.

It is generally accepted that postoperatively radiographic examinations be limited to the area of pathology. The patient presented here complained of visual difficulties two years after transphenoidal removal of a pituitary prolactinoma. His endocrinologist ordered what he believed to be the appropriate computed tomography study and the neuroradiologist did not correctly interpret the new finding of dilated ventricles. Subsequently, a second primary tumor was discovered, a pineal gland sarcoma. The patient had refused radiotherapy after removal of his prolactinoma. Had he not, his second tumor would probably have been attributed to radiation. It is interesting to speculate whether radiation scatter from treatment of the prolactinoma would have prevented the pineal gland sarcoma.

Adenoma↗
PubMedDate not supplied

Seeing but not recognizing.

Visual recognition disturbances are caused by lesions that affect visual cortex as well as white matter connections between visual cortex and temporal and parietal cortex. Homonymous visual field defects are often present but do not explain the recognition difficulty. In "alexia without agraphia" (pure alexia), the intact right visual cortex is disconnected from the left parietal language center by a lesion in the splenium. In "prosopagnosia," visual cortex is disconnected bilaterally from temporal cortex. In simultanagnosia, visual association cortex is damaged. The first condition is most commonly caused by left posterior cerebral artery occlusion, the second by bilateral posterior cerebral artery occlusion or head trauma, and the third by watershed infarction, tumors, abscesses, head trauma, leukoencephalopathies and Alzheimer's disease. When such disorders are suspected, the examiner should supplement the routine visual examination with suggested screening maneuvers.

Adult↗
PubMedDate not supplied

Post-traumatic subgaleal hematoma with subperiosteal orbital extension.

Delayed, progressive proptosis is rare following mild head trauma. We describe a case of subperiosteal orbital extension of a subgaleal hematoma and review ten cases from the literature of solitary subperiosteal hematoma and one of subgaleal hematoma with orbital extension. A patient profile, mode of clinical presentation, management options, and an algorithm for management are presented.

Child↗
PubMedDate not supplied

Chiasmal trauma: clinical and imaging considerations.

This report presents a patient who sustained closed head injury with chiasmal trauma. This uncommon injury may not be apparent on routine imaging studies. It is significant, not only from the visual standpoint, but also because of the association with serious conditions, such as panhypopituitarism, traumatic carotid aneurysm, carotid cavernous fistulae, and meningitis associated with leakage of cerebrospinal fluid. This report demonstrates that magnetic resonance imaging (MRI) is the best method for identifying chiasmal abnormalities.

Accidents, Traffic↗
PubMedDate not supplied

Gliomas of the anterior visual pathway.

Gliomas of the anterior visual pathway are rare orbital lesions accounting for 65% of all intrinsic optic nerve tumors. These lesions occur principally among children in the first decade of life. They appear to be true neoplasms that characteristically show early growth, followed by stability in many patients. Visual prognosis is fair, and the outlook for life depends upon tumor location. When initially confined to the optic nerve alone, overall mortality is about 5%. Once the hypothalamus is involved, mortality rises sharply to over 50%. With involvement of the chiasm or hypothalamus, no form of therapy significantly alters the final outcome. Because of their indolent course, gliomas may be followed conservatively when confined to the optic nerve. In these cases, surgery is indicated only when blindness and pain or severe proptosis intervene. However, all such patients should be followed radiologically for evidence of posterior extension. When the chiasm is threatened, surgical excision via a craniotomy approach is warranted to prevent subsequent hypothalamic or third ventricle involvement. Malignant optic glioma is a distinct disease primarily affecting middle-aged adults. The chiasm is always involved, and although one eye may be spared initially, rapid progression to bilateral blindness is usual. The disease is uniformly fatal.

Adult↗
PubMed1981

Rathke's cleft cyst.

Two cases of Rathke's cleft cyst which produced symptoms of compression of the optic chiasm are described. The first case has been followed for five years since the operation. No evidence of recurrence has been noticed. The prognosis after a partial removal of the cyst wall seems to be good with this lesion. In the second case, there was clinical and laboratory evidence of hypopituitarism and the CT scan revealed suggestive findings to differentiate the cyst from a pituitary adenoma.

Craniopharyngioma↗
PubMed1986

Mucocele of the sphenoid sinus with the apex orbitae syndrome.

A mucocele of the sphenoid sinus with visual impairment and headache is presented. Mucocele of the sphenoid sinus is relatively rare. The preoperative diagnosis was uncertain in this case but sphenoid sinus mucocele was considered. The transnasal surgical approach is considered to be best for treatment.

Adult↗
PubMed1987

Intrasellar arachnoid cysts.

Thirteen pathologically documented intrasellar arachnoid cysts treated by transsphenoidal cyst excision and marsupialization were analyzed. Presenting symptoms included headache (7), visual loss (7), galactorrhea (4), and anterior pituitary dysfunction (2). Postoperatively, the 7 patients with visual loss and 4 with hyperprolactinemia improved. The 2 patients with anterior pituitary dysfunction did not improve and 2 additional patients required hormonal supplements. Based on this operative experience, the pathophysiology of these cysts is discussed. The indications for transsphenoidal exploration include the following: to relieve optic chiasm, pituitary stalk or gland compression, and to exclude the possibility of other sellar neoplasms.

Adenoma↗
PubMed1987

Short-term management of macroprolactinomas with a new injectable form of bromocriptine.

Three cases (2 men, 1 woman) of expansive macroprolactinoma treated with a single 50-mg intramuscular dose of a new form of injectable, long-acting bromocriptine are presented. Clinical manifestations included visual disturbances (2 cases), headache (1 case), and hypogonadism (3 cases). Laboratory tests demonstrated high basal serum prolactin (PRL) levels and evidence of involvement of other anterior pituitary hormones in all cases. Treatment was followed by marked improvement of symptoms paralleled by a sharp decrease of serum PRL levels, which normalized in 1 case. Some other anterior pituitary functions also improved. Computed tomography scan revealed shrinkage of the tumor in all cases. There were no local or serious systemic side effects. These initial findings suggest that long-acting injectable bromocriptine has a place in the initial treatment of macroprolactinomas, especially for those with neurological and/or visual manifestations. It can also be used to select patients for surgery, in the cases where clinical and radiological improvement could not be obtained. The effects of long-term use remain to be established by further studies.

Adult↗
PubMed1988

Cortical blindness caused by acute general cerebral swelling.

A 7-year-old girl who suffered from acute general cerebral swelling as a result of a traffic accident showed cortical blindness. Computed tomography (CT) scan on admission revealed marked slitlike ventricles and narrowing of the perimesencephalic cisterns, which indicated general cerebral swelling. While hospitalized, the patient developed transtentorial herniation twice on day 3, and CT scans at herniation episodes showed disappearance of the perimesencephalic cisterns. After recovery of consciousness, the patient showed cortical blindness, and during gradual recovery she showed pure alexia without agraphia. The visual evoked potentials at 8 weeks, 16 weeks, and 3 years 4 months after trauma showed normalization of the pattern, but revealed left occipital inactivity.

Acute Disease↗
PubMed1993

Intraorbital arteriovenous malformation: case report.

A case of intraorbital arteriovenous malformation presenting with visual loss, exophthalmos, and chemosis of the right eye is reported. Enhanced computer tomography and magnetic resonance imaging showed extraocular muscle enlargement and vascular abnormality in the right retrobulbar space. Angiography revealed an abnormal intraorbital vascular stain with an extremely dilated right ophthalmic artery. Total removal of the intraorbital contents was performed after unsuccessful endovascular and surgical treatment of arteriovenous malformation (AVM). Histopathological examination disclosed an AVM in the retrobulbar fatty tissue with extension into the extraocular muscles and optic nerve.

Adult↗