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PubMed1986

Contusion injuries of the optic nerve.

Indirect trauma to the optic nerve with secondary optic atrophy may result from minor trauma and has traditionally been associated with a poor visual prognosis. The case of a 32-year-old man who suffered a blow to his left supraorbital region and eyebrow in an automatic closing door is reported to draw attention to the uncommon but trivial nature of this injury which may result in profound visual loss. He suffered an initial inferonasal visual field loss which was related to vascular changes in the optic nerve head. Over the ensuing year there was deterioration in his central vision and visual field due to arachnoiditis. Current trends in the management of optic nerve contusion injuries are discussed. There is currently a move towards primary medical management with high-dose corticosteroids as in this case; surgery is reserved for those patients who fail to respond to steroids or deteriorate as the steroid dose is reduced.

Adult↗
PubMed1985

Optic nerve involvement in Graves' ophthalmopathy: a case report and review.

Optic neuropathy in Graves' disease is an uncommon, but potentially treatable cause of disabling visual loss. Optic nerve damage is probably secondary to compression by swollen extraocular muscles at the apex of the orbit. The visual loss is usually bilateral and insidiously progressive, although accelerated visual loss, fluctuations in vision, and features mimicking orbital cellulitis may occur. Ocular congestive symptoms and proptosis have no direct relationship to the severity of visual loss. Early diagnosis is facilitated by orbital CT scanning. Oral corticosteroids and radiotherapy, alone or in combination, are the primary modalities of medical treatment. Surgical decompression of the orbit can be used where medical approaches have failed.

Aged↗
PubMed1988

Primary intracranial plasma-cell granuloma. Case report.

The authors report the fourth case of primary intracranial plasma-cell granuloma. The patient was a 16-year-old girl who presented with loss of vision as the major clinical feature. The tumor resembled a meningioma both preoperatively and grossly at surgery. Because the tumor did not respond to steroid treatment following subtotal surgical excision, radiation therapy was administered to the affected area. Major considerations in the differential diagnosis of this neoplasm are discussed.

Adolescent↗
PubMedDate not supplied

Intravascular thrombosis as a possible cause of transient cortical brain lesions: CT and MRI.

Cortical brain lesions were identified on MRI and CT in 14 patients with a variety of diseases. Each of these patients developed neurologic symptoms, the most prominent of which were seizures, depressed mental status, and blurred vision or cortical blindness. Both the imaging and the neurologic abnormalities resolved spontaneously within a period ranging from 5 to 30 days. Due to location and evolution of the lesions over time we hypothesize that they are secondary to small cortical venous thromboses.

Adolescent↗
PubMed1993

Traumatic optic neuropathy in children: a prospective study.

Fifty children with indirect optic nerve injury were prospectively studied over an 8-year period. They constituted 20% of all patients with optic nerve injury managed on a slightly different protocol. Half of these children were injured due to fall from a height, followed by road traffic accidents in 40% of the cases. Forty-three children had unilateral and 7 children had bilateral visual impairment. Five children had definite history of delayed-onset visual involvement, which ranged from 12 to 72 h following injury. Fifty percent of these children had fractured skulls and 14% had optic canal fracture. Visual evoked potentials were performed in 43 patients of which wave formation was normal in 7 and abnormal in 14 patients. The remaining 22 patients had no wave formation. All the patients were managed conservatively and received corticosteroids for a period of 3 weeks. In 7 children an optic nerve decompression was performed between 4 and 6 weeks following injury. Spontaneous visual improvement was observed in 20 (40%) children. In all the patients onset of visual recovery was noticed within 3 weeks. Of the 7 children who had optic nerve decompression, 4 had minimal spontaneous recovery and their vision remained static. All these 4 children benefited by surgery and the vision improved further following the decompression. Three children had no perception of light prior to surgery and none of these patients showed visual improvement following surgery. The present study brings out the clinical profile of children with optic nerve injury and the indications of surgery in these patients.

Adolescent↗
PubMedDate not supplied

Optic nerve shadow enlargement in the Klippel-Trenaunay-Weber syndrome.

A 10-year-old girl with Klippel-Trenaunay-Weber syndrome (KTWS) showed neuroradiologic signs of enlarged optic nerve and medial rectus shadows. In 3 years of follow-up, her vision has remained normal. This is the first report of optic nerve enlargement in this syndrome. The case demonstrates that enlargement of the optic nerve shadows is not inevitably associated with visual deterioration. Optic nerve enlargement may be part of a hamartomatous process that involves other orbital contents.

Angiomatosis↗
PubMed1995

A brain-damaged patient with an unusual perceptuomotor deficit.

When interacting with objects, the pattern of movements is influenced by such object characteristics as size and position. Little is known about the effect of higher level categorical encoding of objects upon movements. Here we present evidence for an approval-for-action process which takes into account such encoding. For the brain-damaged subject L.P., the ability to complete actions involving two objects in central vision is influenced by the semantic or functional relationship between the objects. Even though she perceives only one object, she can integrate two related objects into a coordinated action. If the objects are not related she is unable to integrate them into a single motor act. We propose that selection-for-action systems include processes which gate conceptually the behavioural disposition to action.

Aged↗
PubMed2002

Pituitary apoplexy presenting with an orbital bruit.

Pituitary apoplexy is a sight-threatening syndrome in which a pituitary adenoma undergoes sudden enlargement as a result of haemorrhage, infarction or both. Classic features of the syndrome include sudden severe headaches, reduced consciousness, visual impairment, ophthalmoplegia and/or endocrinological disturbance. Pituitary apoplexy has been reported following cardiac bypass surgery. The case is reported of a 68-year-old man who presented with left external and internal ophthalmoplegia, complete ptosis, mild chemosis, reduced vision, and an orbital bruit following coronary artery bypass grafting. Carotid angiography showed the left internal carotid artery to be bowed anteriorly and narrowed. Magnetic resonance imaging demonstrated features consistent with pituitary apoplexy. It is believed that an orbital bruit has not previously been reported in pituitary apoplexy.

Adenoma↗
PubMed2005

Primary orbital melanoma associated with a blue nevus.

A 43-year-old white woman presented with a sudden pain and protrusion of the right eye, along with decreased vision. Orbital CT revealed a well-demarcated lesion in the right intraconal space. After surgical excision, the histopathologic examination revealed a malignant melanoma with a predominant epithelioid cell type, probably arising in a blue nevus. The patient was treated with exenteration followed by radiotherapy.

Adult↗
PubMedDate not supplied

Vision despite tomographic absence of the occipital cortex.

A 14-month-old boy with developmental delay showed microcephaly, spastic diplegia, central visual fixation and an esotropia. A head tomographic scan disclosed absence of normal occipital cortex and electroencephalography showed markedly reduced voltages over the occipital region. Visual development in this patient may be related to heterotopic occipital cortex of a functioning non-striate system of visual processing. Visual function cannot be predicted when severe developmental anomalies of the occipital cortex are detected with computerized tomography.

Abnormalities, Multiple↗
PubMed1988

Suprasellar meningiomas: the effect of tumor location on postoperative visual outcome.

The authors reviewed 38 cases of suprasellar meningioma to determine the correlation between tumor site and postoperative visual outcome. Progressive visual loss, the most frequent initial complaint (94.7%), occurred over a mean of 24 1/2 months, was most often unilateral (18 patients) or bilateral but asymmetrical (14 patients), and was severe (20/200 vision or worse) in 23 patients; 24 patients had visual field abnormalities. Computerized tomography or magnetic resonance studies clearly delineated the lesions but did not appear to permit earlier diagnosis. Eleven patients had tumors limited to the tuberculum sellae; the tumor extended from the tuberculum sellae onto the planum sphenoidale in nine patients, into one optic canal in eight, onto the diaphragma sellae in seven, and onto the medial sphenoid wing in three. Patients with tumors affecting the optic canal had severe unilateral visual loss more often than those with tumors at other sites. Tumors limited to the tuberculum sellae were most often completely resected; postoperative recovery of vision was also most frequent in patients with tumors at this site. Tumors involving the diaphragma sellae or the medial sphenoid wing were least often completely removed and most likely to be associated with postoperative visual deterioration. Overall, 42% of patients had improved vision postoperatively, 30% remained unchanged, and 28% were worse. After a mean follow-up period of 38 months, 24 patients are doing well, four have significant visual disability, and three are blind or doing poorly. Two patients died of causes unrelated to their tumor. Three patients have had tumor recurrence.

Adult↗
PubMed2006

Perspective on strabismus, 2006.

During the last half of the 20th century, the field of strabismus did not undergo as many major advances as other areas of ophthalmology. In recent years, an increase in basic science research has fostered important advances in our understanding and treatment of disorders of binocular vision. This article identifies 4 important questions that need to be addressed by the pediatric ophthalmology and adult strabismus community: (1) What terms should be used to describe muscle dysfunction? (2) By what mechanism does strabismus surgery work? (3) What is the role of orbital imaging in the management of strabismus? (4) What is the role of refractive surgery in the treatment of patients with amblyopia and strabismus?

Adult↗
PubMed1984

[Eye symptoms in hypophyseal adenomas, craniopharyngiomas and meningiomas of the anterior and middle cranial fossa].

Among 181 inpatients suffering from pituitary adenoma, craniopharyngioma, or meningioma of the anterior or middle cranial fossa, 112 had ocular symptoms initially or during the course of the disease. Patients' histories were analyzed with regard to ophthalmological, neurological, and radiological diagnostic procedures carried out, and the conclusions drawn from these. Initial symptoms and signs were often misinterpreted and appropriate investigations consequently delayed. The mean duration of the history was 2.67 years (0-13 years) for the pituitary adenomas, 1.44 years (3 months-6 years) for the craniopharyngiomas and 3.73 years (1 month-24 years) for the meningiomas. Typical initial eye symptoms were progressive loss of vision with or without optic nerve atrophy, visual field defects, extraocular nerve palsies, and exophthalmus, the last two occurring if parasellar extension of the tumor was present. Plain skull X-rays were abnormal in nearly all cases of pituitary adenomas, but the incidence of abnormalities was less frequent with cases of craniopharyngiomas and meningiomas. The tumor was demonstrated by computerized tomography in all cases of pituitary adenomas, in 5 out of 6 cases with craniopharyngiomas and, where the examination was performed before and after administration of contrast medium, in all cases of meningiomas. Introduction of CT, however, shortened the duration of the history only in the meningioma group; the mean dropped from 4.38 years to 3.04 years. The chance of achieving a cure by surgical intervention lessened with both increasing length of history and tumor size. Out of 90 patients (15.6%) operated on, 14 died in the postoperative period. Vision improved postoperatively in only 26 patients whereas it remained unchanged or decreased further in 40 patients. In 10 cases there were no postoperative data available. These results emphasize the necessity of making an early diagnosis. This can nearly always be achieved if a careful clinical examination and adequate additional diagnostic procedures are carried out.

Adenoma↗
PubMed1990

Reversible visual loss caused by fibrous dysplasia.

Fibrous dysplasia is a developmental anomaly of bone, often affecting the facial bones. We treated a patient who had fibrous dysplasia involving the right maxillary and sphenoid bones. The patient had a sudden loss of visual acuity to R.E.: counting fingers. Visual fields demonstrated a central scotoma, and retrobulbar neuritis was diagnosed. When vision failed to improve spontaneously, however, radiologic studies were performed. These showed compromise of the optic canal by bony proliferation and an apparent mucocele at the orbital apex. Surgical exploration disclosed fibrous dysplastic bone and a cystic structure overlying the optic nerve. Successful surgical excision of the cyst and debulking of the fibrous dysplasia resulted in visual acuity returning to R.E.: 20/25.

Adult↗
PubMed2005

A web-based remote collaborative system for visualization and assessment of semi-automatic diagnosis of liver cancer from CT images.

We propose a web-based collaborative CAD system allowing for the remote communication and data exchange between radiologists and researchers in computer vision-based software engineering. The proposed web-based interface is implemented in the Java Advanced Imaging Application Programming Interface. The different modules of the interface allow for 3D and 2D data visualization, as well as for the parametric adjustment of 3D reconstruction process. The proposed web-based CAD system was tested in a pilot study involving a limited number of liver cancer cases. The successful system validation in the feasibility stage will lead to an extended clinical study on CT and MR image databases.

Diagnosis, Computer-Assisted↗
PubMed1985

[Visual field defects in hydrocephalus].

Eight patients representing visual field defects associated with hydrocephalus are reviewed. Seven cases had aqueductal stenosis and one had congenital communicating hydrocephalus. We found five cases of defects in visual field typical of a chiasmal or optic nerve lesion: (1) inferior altitudinal hemianopia with inferior nasal quadrantanopia in the opposite eye; (2) inferior binasal quadrantanopia; (3) unilateral inferior nasal depression; (4) unilateral temporal defect; (5) bilateral central scotoma. In these cases CT demonstrated moderate or marked symmetrical dilatation of the third and lateral ventricles. Four out of five cases showed bulging of the third ventricle anteriorly into the sella turcica on CT or ventriculography. Other three patients had incongruous homonymous hemianopia. Characteristic asymmetrical dilatation of the lateral ventricles was noted in all three cases. The more enlarged lateral ventricles were ipsilateral with the affected visual pathways. The sites of lesion responsible for these field defects seemed to be optic tract in one case and optic radiation in two cases. Ventriculoperitoneal shunt was placed in five out of seven cases. Impaired visual field improved in three patients after shunt insertion. A 28-year-old female who had history of blurred vision fos 14 days showed improvement in visual acuity and field when the enlarged ventricles became slit-like by shunting. In the other two patients defects in visual fields improved in spite of consistent ventriculomegaly. These facts suggested that not only the mechanical forces with distended third ventricle but also increased intracranial pressure played an important role in producing visual field defects in hydrocephalic patients.

Adolescent↗
PubMed1996

Ocular findings in children operated on for plagiocephaly and trigonocephaly.

Clinical examination of patients affected by plagiocephaly or trigonocephaly reveals evident malformation of the orbits, and the ocular repercussions are pronounced when children are operated on at an advanced age. Since it is generally accepted that binocular vision is fully developed by approximately 6 months of age, a late correction of plagiocephalic or trigonocephalic skull deformities may be an obstacle to the development of normal visual function. For the present report we investigated astigmatism and strabismus in 53 children, 39 of whom were operated on for plagiocephaly and 14 for trigonocephaly. Traction on the ocular globe induced by the bony deformation caused by the craniosynostosis may explain astigmatism and strabismus.

Astigmatism↗