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Biomedical subjects

N R Miller

Publications and source records attributed to N R Miller.

At least 181 records · Page 10Linked to original sources
PubMed1985

The risk of cerebrovascular and cardiovascular disease in patients with anterior ischemic optic neuropathy.

Of 217 patients in whom anterior ischemic optic neuropathy (AION) was diagnosed during the period from 1975 to 1985, verifiable medical information was obtained for 212 (98%). Over a median follow-up period of three years, no group of patients had an increased mortality rate over that of age-, sex-, and race-matched controls; however, patients with "idiopathic" AION and patients with systemic hypertension who developed nonarteritic AION had a statistically significant increased risk of experiencing cerebrovascular events and myocardial infarctions compared with appropriately matched control groups. In view of the findings of our study, we suggest that patients with idiopathic AION and hypertensive patients who develop nonarteritic AION undergo a complete physical examination, cardiac evaluation, tests of carotid artery patency, and careful medical follow-up to attempt to prevent subsequent cerebrovascular or cardiovascular events.

Adult↗
PubMed1985

Visual function following optic canal decompression via craniotomy.

Visual function was assessed in 15 eyes of 11 patients who underwent unilateral (seven patients) or bilateral (four patients) optic canal decompression for presumed compressive optic neuropathies. Both immediate and long-term postoperative vision was evaluated in all eyes. Over 90% of the eyes that had undergone nerve decompression had either the same or improved visual acuity and visual field immediately following surgery. In this group of patients there were no deaths and there was only one postoperative complication, a transient dysphasia caused by an epidural hematoma that was evacuated. Long-term follow-up evaluations revealed that most of the eyes retained their immediate postoperative visual function or showed gradual visual improvement with time. The results of this series as well as a review of the available literature indicate that optic canal decompression via craniotomy can be a safe procedure and that it appears to have lasting visual benefit in many patients.

Adolescent↗
PubMed1984

Pseudotumor cerebri.

Two young women with idiopathic pseudotumor cerebri were treated successfully with lumboperitoneal shunts. Their shunts were removed electively several years later, following which there was rapid increase of cerebrospinal fluid pressure. In one patient, rapid increase of intracranial pressure resulted in bilateral visual loss. These cases provide further evidence that idiopathic pseudotumor cerebri may not be a self-limited condition.

Adult↗
PubMed1984

Visual results after microsurgical removal of meningiomas involving the anterior visual system.

Visual results were evaluated in 20 patients after microsurgical removal of intracranial meningiomas that had produced visual loss from damage to the anterior visual system. Patients were evaluated preoperatively, immediately postoperatively, and several months to years after surgery. Visual acuity either improved or remained normal in 68.75% (22/32) of eyes examined and worsened in 25% (8/32) of eyes examined. Visual field changes generally paralleled visual acuity changes. Visual results were most closely related to duration of visual symptoms and not to either tumor size or preoperative visual findings.

Adult↗
PubMed1984

Neuroretinitis.

Twelve patients had neuroretinitis characterized by optic disc swelling with marked peripapillary and macular exudates. Individual cases demonstrated bilateral involvement, associated chorioretinitis, and symptoms and signs indicating extraocular CNS involvement. Detailed diagnostic investigation, performed in half of the cases, failed to demonstrate a cause. A temporal relationship to viral disease was present in five of 12 cases, although clinical findings in some cases indicated the condition does not simply represent a monophasic response to viral illness. Regardless of the degree of initial visual impairment or the severity of disc swelling and retinal involvement, ultimate visual outcome was generally excellent, but visual impairment persisted in some patients.

Adolescent↗
PubMed1984

Evaluation of nerve fiber layer assessment.

More than 1,400 eyes with either ocular hypertension glaucomatous visual field loss, or normal pressures and fields (controls) were studied prospectively in standardized, masked fashion. The appearance of the nerve fiber layer was evaluated independently from red-free photographs with the discs blocked-out by two observers. The vast majority of photographs could be evaluated, the proportion varying with the observer and with the age and clinical status of the subject. Sensitivity (proportion of glaucomatous eyes with nerve fiber defects) and specificity (proportion of normal control eyes without defects) averaged 80% to 94%, varying with the observer and with the age, race, and severity of field loss. In two thirds of presumed false-positive eyes, but only 5% of true-positive eyes, the abnormalities were limited to focal slitlike defects. The prevalence of nerve fiber defects in eyes with elevated pressure and normal visual fields was similar to that in control eyes, approximately 10%. However, the proportion of eyes in which these defects included diffuse loss was considerably higher among the hypertensive eyes.

Adult↗
PubMed1984

Capillary hemangioma of the sphenoid bone.

A capillary hemangioma in the body of the sphenoid bone produced unilateral optic atrophy in a 13-year-old boy. The typical reticulated appearance of an osseous hemangioma was clearly demonstrated only on direct magnification radiographs. At angiography, patchy filling occurred through vessels arising from the internal carotid and internal maxillary arteries bilaterally. The few other reports of sphenoid hemangiomas are reviewed.

Adolescent↗
PubMed1984

Brain tumors of owl monkeys inoculated with JC virus contain the JC virus genome.

The DNA from astrocytomas that developed in adult owl monkeys 16 to 36 months after intracranial inoculation with JC virus (JCV) was examined for the presence of the JCV genome by hybridization to cloned JCV DNA. The JCV genome was found to be integrated into the cellular DNA in all tumors examined. There was no JCV DNA in normal, uninvolved brain tissue from the same animals. Integration of the genome occurred at a limited number of sites in the cellular DNAs, indicating a clonal origin for the tumors, but none of the tumors had integration sites in common. In all but one of the tumors, there was tandem, head-to-tail integration of two or more copies of the JC genome. In a tumor which had only one integration site and could be analyzed more extensively, there appeared to be a complete copy of the JCV genome present, although deletions of small portions of the genome would not have been detected.

Animals↗
PubMed1984

Optic neuropathy from the use of intracranial muslin.

Following repair of an anterior communicating artery aneurysm with McFadden clips and muslin, a 32-year-old woman developed a steroid-responsive optic neuropathy. When she was explored, a sterile abscess with surrounding fibrotic tissue involving the muslin was found adjacent to the right optic nerve. The patient's vision improved following removal of the abscess.

Abscess↗
PubMed1984

Papilledema and dural sinus obstruction.

We present two cases of meningioma obstructing the posterior sagittal sinus, producing elevated intracranial pressure and papilledema by impairing cerebral venous drainage. In both patients, this mechanism was not recognized preoperatively and resulted in optic atrophy and significant visual loss.

Brain Neoplasms↗
PubMed1983

Monocular polyopia.

A patient with monocular polyopia underwent extensive neurologic investigation over a two-year period. Ocular examination disclosed a corneal degenerative change as the cause, and symptomatic relief was obtained with pilocarpine hydrochloride drops.

Corneal Diseases↗
PubMed1983

Optic tract syndrome. Neuro-ophthalmologic considerations.

A review of the case histories of ten patients with optic tract lesions, an uncommon clinical entity, showed the primary characteristic to be a homonymous visual field defect that may be complete or incomplete. When the defect is incomplete, there is relative incongruity. When it is complete, there is an associated contralateral relative afferent pupillary defect. Visual acuity and color vision are preserved, unless there is bilateral involvement or anterior extension to involve the optic nerve or chiasm. When of sufficient duration, the contralateral fundus demonstrates band or "bow tie" atrophy of the disc and nerve fiber layer.

Adolescent↗
PubMed1983

Chiasmatic and hypothalamic extension of optic nerve glioma.

An 11-year-old boy was found to have a left optic nerve glioma confined to the orbit and optic canal by clinical examination and computed tomographic (CT) scanning. Repeated neuroradiologic examinations demonstrated intracranial extension of tumor to involve the hypothalamus and third ventricle. Following craniotomy and verification of the diagnosis of glioma by biopsy, the patient underwent a course of radiotherapy that resulted in marked tumor regression. The potential for growth of optic nerve gliomas mandates careful neuroradiologic follow-up regardless of whether there is ophthalmologic deterioration. The natural history of "optic gliomas" remains unknown.

Cerebral Ventricles↗
PubMed1983

A clinicopathologic study of optic neuropathies associated with intracranial mass lesions with quantification of remaining axons.

We examined three patients with intracranial mass lesions that damaged the anterior visual pathway and studied this damage histologically after the patients died. Estimation of the number of surviving axons in the six optic nerves generally showed the greatest atrophy to be in the temporal sector in cross sections immediately behind the globe. More posterior to the globe, atrophy appeared greatest in the center of several nerves. This pattern of damage may result from particular vulnerability of macular axons to damage along the anterior visual pathway. Optic disk pallor was present in two eyes that had less than 40% of the normal number of axons remaining, while one optic disk appeared to be normal with 70% of the axons intact. Afferent pupillary defects were observed in two patients who had two to three times as many remaining axons in the contralateral optic nerve as in the nerve on the side of the defect.

Adenoma↗
PubMed1983

Ocular clinicopathologic correlation of Hallervorden-Spatz syndrome with acanthocytosis and pigmentary retinopathy.

We studied the eyes of a 10-year-old girl with retinal degeneration, acanthocytosis, and normal betalipoprotein levels. The ophthalmoscopic pattern was characterized initially by a flecked retina and later by bone-spicule formation and "bull's-eye" annular maculopathy. On ultrastructural study, the retinal pigment epithelium varied in size and contained large, round single-membrane-bound aggregates composed of complex melanolipofuscin granules. Cells that had migrated into the outer retinal layers contained similar melanolipofuscin aggregates; these cells were identified as macrophages and correlated with the flecks and macular annulus seen on ophthalmoscopy. The cells around the retinal blood vessels contained normal melanin pigment, were identified as retinal pigment epithelial cells, and correlated with the bone spicule pigmentation found on ophthalmoscopic examination.

Basal Ganglia Diseases↗
PubMed1983

Sclerosteosis: neurogenetic and pathophysiologic analysis of an American kinship.

We studied an American kinship with sclerosteosis, an autosomal-recessive disorder of bone remodeling and bone overgrowth of the calvaria, skull base, and tubular bones. Unlike osteopetrosis, which is attributed to abnormal immune and osteoclast function as well as bone resorption, sclerosteosis appears to be primarily a disorder of osteoblast (bone formation) hyperactivity. Related to cranial vascular and neural foraminal narrowing and reduced intracranial volume, affected patients with sclerosteosis demonstrate frequent seventh nerve palsy, progressive optic and cranial neuropathies, mixed hearing loss, brainstem compression, intracranial hypertension with increased elastance, and sudden, premature death. Management should involve early childhood identification of homozygotes, monitoring and aggressive treatment of intracranial hypertension, and extensive bone removal from skull, posterior fossa, and cervical spine.

Adult↗