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PubMed2004

[A case of adenocarcinoma of the lung presenting symptoms of choroidal metastasis as the initial clinical manifestation].

A 51-year-old woman was referred to our hospital with a complaint of disturbance in vision. Ophthalmologic examination revealed multiple choroidal tumors. High-resolution CT showed a nodular shadow in the left lower lobe. Transbronchial biopsy and right supraclavicular lymph node biopsy specimens showed a poorly-differentiated adenocarcinoma. We concluded that the choroidal tumors had metastasized from the lung. Combined chemotherapy (CDDP + CPT-11) followed by irradiation of both eyes and brain were performed. Nevertheless, she died 6 months after the initial presentation. It is important to notice ophthalmologic symptoms because lung cancer may metastasize to the choroids.

Adenocarcinoma↗

PubMedDate not supplied

Unilateral exophthalmos associated with severe fibrous dysplasia.

Fibrous dysplasia is a benign developmental anomaly of bone, often affecting craniofacial bones. We report on a 9-year-old boy, who presented for routine checkup. Clinical examination revealed unilateral exophthalmos of his left eye without decrease of visual acuity or double vision. Radiologic studies showed characteristic extensive changes of fibrous dysplasia involving the left frontal bone, left orbital bones, maxillary and sphenoid bones. The patient was started on conservative therapy and the condition of the affected eye remained stable. As fibrous dysplasia of the orbital bones can be a cause of significant dysfunction and a treatable cause of blindness, early diagnosis is very important. These patients are most likely to present with complaints of facial asymmetry, including axial, vertical, or horizontal displacement of the globe, or visual loss. Therefore the ophthalmologist plays an important role in the early diagnosis of fibrous dysplasia.

Antineoplastic Agents↗

PubMed2002

Vision recovery following nasopharyngeal angiofibroma excision.

'Juvenile' nasopharyngeal angiofibroma is a locally aggressive, yet histologically benign, vascular neoplasm. This neoplasm accounts for less than 0.5% of head and neck neoplasms. We report an unique case of a 14-year-old male with a nasopharyngeal angiofibroma compressing the optic nerve and causing great visual impairment. The tumor was a red lobulated mass in left nostril, invading maxillary sinus, anterior and posterior ethmoid sinus, sphenoid sinus, and cavum area. Midfacial degloving approach and total excision of the tumor resulted in almost completely visual recovery. Optic nerve decompression was not performed. We consider that an early diagnosis, an adequate approach, total tumor excision, and efforts by a team of sub-specialists are most likely to yield optimal results.

Adolescent↗

PubMed1998

Presumed bilateral occipital neurosarcoidosis. A case report.

A 37-year-old man with a history of sarcoidosis, hypertension, asthma, depression and prior intravenous drug use presented with complaints of difficulty in finding his way around the house, headache, and blurred vision in both eyes. The symptoms had been increasing in severity over the prior several months. Physical examination showed normal visual acuity, pupil reactions, and fundi but severe, circumferential constriction of the visual fields bilaterally. The visual fields enlarged appropriately on increasing the distance from the patient to the tangent screen. Neuroimaging revealed bilateral, occipital meningeal involvement and parenchymal lesions consistent with sarcoidosis. Treatment with oral corticosteroids produced a mild subjective improvement in the patient's symptoms and stabilized the visual fields, without improving them. This case represents an unusual presentation of presumed neurosarcoidosis involving the visual pathways at the level of the occipital lobes.

Adult↗

PubMed1989

Surgical treatment of progressive visual loss in traumatic optic neuropathy. Report of two cases.

In two patients with traumatic optic neuropathy progressive visual loss was reversed by surgical decompression of the optic nerve sheath. The first patient with hemorrhage beneath the optic nerve sheath had progressive loss of vision from counting fingers to no light perception within 24 hours after the injury. Surgical evacuation of the hematoma improved visual acuity to 8/30. The second patient had progressive visual loss from 20/20 to 20/400 within the 1st week after injury. Drainage of an arachnoid cyst of the optic nerve sheath improved visual acuity to 20/25. Computerized axial tomography disclosed the hemorrhage in the first case and enlargement of the optic nerve sheath in the second. While the management of traumatic optic neuropathy is controversial, surgical intervention for an arachnoid cyst and hematoma involving the optic nerve is clearly beneficial.

Adult↗

PubMed1986

Circulatory parameters of the retina in patients with lacunar stroke.

Ophthalmological data were obtained in 40 patients presenting with lacunar stroke. The stroke was verified clinically as well as by computed tomography. Vision was tested and the visual field, intraocular pressure, retinal arteriovenous passage time, arm-retina time, and erythrocyte flow velocity in the conjunctival capillaries were all determined; ophthalmoscopy was also carried out. Microcirculatory parameters were obtained from 21 patients. Significant disturbances of the retinal arteriovenous passage time were observed, but there were no significant disturbances of the conjunctival erythrocyte flow velocity. The concurrently measured haemorheological parameters were all pathological with the exception of the haematocrit. Ophthalmoscopic examination revealed arteriosclerotic alterations in 38 of 40 patients. These angiological and rheological findings confirm the importance of disturbed microcirculation in lacunar stroke.

Aged↗

PubMed1988

Sneddon's disease presenting with visual loss and dementia.

A 51-year-old woman with Sneddon's disease presented with transient right hemifield loss of vision and transient right-sided weakness. Over the preceding decade she had experienced a slow decline in mental function. She also had hypertension, migraine, and a mixed seizure disorder. She had skin changes typical for generalized livedo reticularis but she did not have Raynaud's phenomenon or winter ulcerations. Her disease was not understood until the stroke-related symptoms were associated with the skin abnormalities. We review the neuro-ophthalmic manifestations of Sneddon's disease and add data from our case to the growing body of fact that suggests that Sneddon's disease may be an immunologically mediated vasculopathy.

Cerebrovascular Disorders↗

PubMed1995

Live cell image segmentation.

A major requirement of an automated, real-time, computer vision-based cell tracking system is an efficient method for segmenting cell images. The usual segmentation algorithms proposed in the literature exhibit weak performance on live unstained cell images, which can be characterized as being of low contrast, intensity-variant, and unevenly illuminated. We propose a two-stage segmentation strategy which involves: 1) extracting an approximate region containing the cell and part of the background near the cell, and 2) segmenting the cell from the background within this region. The approach effectively reduces the influence of peripheral background intensities and texture on the extraction of a cell region. The experimental results show that this approach for segmenting cell images is both fast and robust.

Algorithms↗

PubMed2006

Three-dimensional reconstruction and quantitative analysis of the brain stem nuclei based on fast centroid auto-registration.

This paper introduces a three-dimensional (3D) reconstruction algorithm of the brain stem nuclei based on fast centroid auto-registration. The research is based on methods and theories of computer stereo vision, and by image information processing three-point pattern local search, registration and auto-tracing for the centroids of the brain stem nuclei were accomplished. We adopt two-peak threshold, edge detection and grayscale image enhancement to extract contours of the nuclei's structures. The experimental results obtain the spatial structure information and 3D image of the brain stem nuclei, show spatial relationship between 14 pairs of nuclei, and quantitate morphological parameters of each type of nuclei's 3D structure. This work is significant to neuroanatomy research and clinic applications. Furthermore, a software system named BRAIN.HUK is established.

Algorithms↗

PubMed1994

Endovascular treatment of giant aneurysms which cause visual loss.

BACKGROUND: Progressive visual loss that results when a giant cerebral aneurysm compresses the anterior visual pathway requires treatment. When surgical clipping is not safely feasible, percutaneous methods of embolization of the aneurysm can be visual or life saving. METHODS: Endovascular techniques were used to treat 19 of 26 consecutive inoperable giant aneurysms in patients with visual loss, which included optic neuropathy (monocular in 13 patients and bilateral in 8) and optic tract dysfunction in five patients. Embolization of the aneurysm was performed with detachable balloons in 12 patients and with Guglielmi detachable electrocoils in 7. RESULTS: After treatment, vision improved in 7 patients, was unchanged in 11, and worsened in 1. Neurologic complications with balloons were temporary in four patients and severe and permanent in three. In contrast, only one temporary complication occurred with Guglielmi detachable electrocoils. The treatment results are contrasted with the outcome in the seven patients who refused intervention: three hemorrhaged (1 death); monocular blindness with dementia developed in two; a complete homonymous hemianopia and dementia developed in one; and one became bilaterally blind. CONCLUSION: Inoperable symptomatic giant aneurysms can be successfully treated with endovascular treatment.

Adolescent↗

PubMed1987

Myxoedema presenting with chiasmal compression: resolution after thyroxine replacement.

A 60-year-old woman presented with deteriorating vision. A computed tomography (CT) scan showed pituitary enlargement with chiasmal compression. Serum prolactin levels were normal but assessment of thyroid function showed a serum thyroxine level of 25 nmol/l (normal range 76-160 nmol/l) and a thyroid-stimulating hormone (TSH) level of 60 mU/l (normal range 0.5-5.0 mU/l). After 8 weeks of thyroxine replacement therapy (0.05 mg daily increasing to 0.1 mg daily after 3 weeks) the visual defects had resolved, serum TSH had fallen to 0.7 mU/l, and the CT scan showed pronounced reduction in the size of the pituitary gland. Measurement of TSH as well as prolactin is essential in all patients with pituitary enlargement, to avoid unnecessary pituitary surgery.

Female↗

PubMed1997

Vision without knowledge.

A brain-damaged patient (D.F.) with visual form agnosia is described and discussed. D.F. has a profound inability to recognize objects, places and people, in large part because of her inability to make perceptual discriminations of size, shape or orientation, despite having good visual acuity. Yet she is able to perform skilled actions that depend on that very same size, shape and orientation information that is missing from her perceptual awareness. It is suggested that her intact vision can best be understood within the framework of a dual processing model, according to which there are two cortical processing streams operating on different coding principles, for perception and for action, respectively. These may be expected to have different degrees of dependence on top-down information. One possibility is that D.F.'s lack of explicit awareness of the visual cues that guide her behaviour may result from her having to rely on a processing system which is not knowledge-based in a broad sense. Conversely, it may be that the perceptual system can provide conscious awareness of its products in normal individuals by virtue of the fact that it does interact with a stored base of visual knowledge.

Adult↗

PubMed1997

Chewing-induced visual impairment from a dumbbell dermoid cyst.

A 29-year-old woman presented with a 1-year history of blurred vision in her left eye while chewing. Examination revealed a rubbery mass with ill-defined borders in the superotemporal brow region. Imaging studies demonstrated a cystic lesion extending from the temporal fossa into the orbit through a bony defect in the lateral orbital wall, assuming a dumbbell configuration. Histopathology of the excised specimen confirmed the clinical diagnosis of a dermoid cyst of cutaneous origin. We believe that the patient's visual disturbance was caused by transient displacement of orbital contents by the dermoid cyst as it was compressed into the orbit during mastication. Dermoid cysts are frequently associated with bony defects, which may require preoperative imaging and may produce unexpected symptoms.

Adult↗

PubMed1999

Human cortical areas activated in relation to vergence eye movements-a PET study.

Human cortical areas activated in relation to vergence eye movements were determined using positron emission tomography. Binocular disparity-driven visual stimuli were presented using a head-mounted display. Eye movements were monitored continuously by an infrared limbus tracker. A combination of a bar and a cross was used as the target. In the vergence task, subjects were instructed to follow an approaching bar, while ignoring a stationary cross. Activation in relation to vergence eye movement was discriminated from activation in relation to motion vision by using the ignore-bar task as the control. In the ignore-bar task, subjects were instructed to fixate on a stationary cross, while ignoring an approaching bar. The fixation task was used as the basic control for both the vergence and the ignore-bar tasks. Areas of activation in relation to vergence eye movements were found in the bilateral temporooccipital junction, the left inferior parietal lobule, and the right fusiform gyrus by comparing regional cerebral flow between the vergence and ignore-bar tasks and by the conjunctive analyses of vergence-vs-ignore comparison with vergence-vs-fixation comparison.

Accommodation, Ocular↗

PubMedDate not supplied

Impaired capacity of cerebellar patients to perceive and learn two-dimensional shapes based on kinesthetic cues.

This study addresses the issue of the role of the cerebellum in the processing of sensory information by determining the capability of cerebellar patients to acquire and use kinesthetic cues received via the active or passive tracing of an irregular shape while blindfolded. Patients with cerebellar lesions and age-matched healthy controls were tested on four tasks: (1) learning to discriminate a reference shape from three others through the repeated tracing of the reference template; (2) reproducing the reference shape from memory by drawing blindfolded; (3) performing the same task with vision; and (4) visually recognizing the reference shape. The cues used to acquire and then to recognize the reference shape were generated under four conditions: (1) "active kinesthesia," in which cues were acquired by the blindfolded subject while actively tracing a reference template; (2) "passive kinesthesia," in which the tracing was performed while the hand was guided passively through the template; (3) "sequential vision," in which the shape was visualized by the serial exposure of small segments of its outline; and (4) "full vision," in which the entire shape was visualized. The sequential vision condition was employed to emulate the sequential way in which kinesthetic information is acquired while tracing the reference shape. The results demonstrate a substantial impairment of cerebellar patients in their capability to perceive two-dimensional irregular shapes based only on kinesthetic cues. There also is evidence that this deficit in part relates to a reduced capacity to integrate temporal sequences of sensory cues into a complete image useful for shape discrimination tasks or for reproducing the shape through drawing. Consequently, the cerebellum has an important role in this type of sensory information processing even when it is not directly associated with the execution of movements.

Adult↗

PubMed1998

Neurological deterioration following head injury: the eyes had it.

A 17-year-old male presented with confusion following a mild head injury. Repeated CT scans of the head were normal. There was a 3 year history of decreased vision, associated with a focal pigmentary retinopathy. On assessment he demonstrated visual agnosia and early dementia. An MRI scan showed symmetrical demyelination of the white matter, particularly of the occipital lobes. The diagnosis of subacute sclerosing panencephalitis (SSPE) was confirmed by the typical EEG findings and the presence of measles antibodies in the CSF. The head injury was the precipitating factor which led to a diagnosis of SSPE. This disease should be considered in young patients who have persisting cognitive dysfunction out of keeping with the severity of the initial trauma. A focal pigmentary retinopathy, especially with macular involvement, should also raise the possibility of SSPE, despite the absence of neurological symptoms initially. We report the longest interval to date between the visual symptoms and onset of neurological signs of SSPE.

Adolescent↗

PubMed1985

Otolaryngologists' role in diagnosis and treatment of orbital pseudotumor.

Patients with pseudotumor of the orbit often present with proptosis, inflammatory changes of the orbital structures, loss of vision, and abnormalities of extraocular motility. Because these signs and symptoms mimic more common disorders of the paranasal sinuses, the otolaryngologist often plays an important role in the diagnosis of this clinical entity. Also, since orbital pseudotumor can be secondary to an inflammatory disease of the paranasal sinuses, appropriate medical and surgical treatment must be rendered by the otolaryngologist. The experience of orbital pseudotumor at Indiana University Medical Center in the Department of Otolaryngology-Head and Neck Surgery is presented. Appropriate diagnostic workup is discussed, including the importance of the CT scan. The differential diagnosis of space-occupying orbital processes is examined. It is important that the otolaryngologist become more familiar with this clinical entity and its appropriate treatment.

Adult↗

PubMed1995

[Intra-orbital hydatid cysts. 10 cases].

Ten cases of intra-orbital hydatid cysts were operated from January 85 to December 91. The aim of this retrospective study is to show the importance of this pathology with regard to other intra-orbital expansive processes and to discuss the efficiency of neurosurgical approaches. The mean age was 25 years, with 5 women and 5 men. The symptoms consisted in progressive unilateral exophthalmia in 8 cases and acute one in 2 cases. Visual deterioration was observed in 7 cases: a reduced vision acuity in 6 cases and blindness in one case. Fundus oculi showed papillary oedema in 4 cases and optical atrophy in one case. Slight disturbance of ocular mobility was observed in 5 cases. CT Scan gave positive diagnosis and predicted the hydatid nature in 9 cases. Fronto-orbital approach, taking away the squamous portion of the frontal bone, orbital arc and roof, was made in 9 cases. It permitted to remove the cyst without rupture of the capsule in all cases. Fronto-temporal approach was used in one case. The evolution was excellent after 8 months to 6 years in 4 patients. Five patients were improved with reduction of exophthalmia, stabilisation of visual acuity and eye movements. Blindness remained unchanged in one patient.

Adolescent↗