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Biomedical subjects

N R Miller

Publications and source records attributed to N R Miller.

At least 73 records · Page 4Linked to original sources
PubMed1998

Familial Axenfeld-Rieger anomaly, atrial septal defect, and sensorineural hearing loss: a possible new genetic syndrome.

OBJECTIVE: To describe the clinical and ocular histopathological findings in multiple members of a family with congenital Axenfeld-Rieger anomaly, atrial septal defect, and sensorineural hearing loss. METHODS: We performed a retrospective review of the medical charts and the ocular histopathological material of multiple members of a family. RESULTS: Congenital Axenfeld-Rieger anomaly and glaucoma were inherited by both the proband and her male half-sibling from a phenotypically positive father and 2 different phenotypically negative mothers, suggesting an autosomal dominant inheritance. The proband's male half-sibling and her father also had atrial septal defects and sensorineural hearing loss. The proband's paternal grandmother had severe glaucoma. Histopathological analysis of blind, painful eyes removed from the proband's father and paternal grandmother showed incomplete development of the anterior chamber angle with iris stromal hypoplasia, prominent posterior embryotoxon with iris adhesions, and abnormal position and insertion of the ciliary muscles. CONCLUSIONS: This is the first description of coexisting Axenfeld-Rieger anomaly, atrial septal defect, and sensorineural hearing loss in multiple members of a single family. The iris, trabecular meshwork, and large portions of the cardiac intraventricular septum all arise from neural crest anlagen, thus supporting the notion that anterior segment dysgenesis represents a developmental disorder of the neural crest.

Abnormalities, Multiple↗
PubMed1998

Spontaneous remission in patients with essential blepharospasm and Meige syndrome.

PURPOSE: To determine the frequency of remission in patients with essential blepharospasm and Meige syndrome. METHOD: Retrospective analysis of patients by means of questionnaire in an institutional setting. RESULTS: Among 238 patients diagnosed in a single institution as having essential blepharospasm or Meige syndrome, 27 (11.3%) claimed to be symptom free without curative surgery. The average time between onset and resolution in the patients who claimed remission was 4.85 years (range, 3 months to 22 years). Among these patients, the duration of remission averaged 6.33 years (range, 1 year to 14 years). CONCLUSION: Patients with essential blepharospasm or Meige syndrome have a small but definite potential for spontaneous remission of symptoms, particularly within the first 5 years after onset of symptoms.

Blepharospasm↗
PubMed1998

Herpes simplex encephalitis and bilateral acute retinal necrosis syndrome after craniotomy.

PURPOSE: Acute retinal necrosis (ARN) syndrome is associated with members of the herpes virus family, but the mechanisms of infection remain unclear. The purpose of this study is to report a unique case of acute retinal necrosis syndrome associated with herpetic encephalitis in order to elucidate possible factors involved in herpetic central nervous system disease. METHOD: Case report. RESULTS: A 64-year-old woman who developed acute herpes simplex virus encephalitis associated with bilateral acute retinal necrosis syndrome after craniotomy for resection of a suprasellar craniopharyngioma is presented. The results of lumbar puncture, magnetic resonance imaging, and ophthalmologic examination are consistent with herpetic infection. The origin of acute retinal necrosis syndrome and the association of acute retinal necrosis syndrome with encephalitis are reviewed. CONCLUSIONS: After craniotomy, we hypothesize reactivation of previously latent herpes simplex virus in the area of the inferior frontal lobe and optic chiasm. Reactivated virus may have migrated to the retina by axonal transport, through the optic nerves, to produce the acute retinal necrosis syndrome.

Acyclovir↗
PubMed1998

Relative afferent pupillary defects in patients with Leber hereditary optic neuropathy and unilateral visual loss.

PURPOSE: It has been suggested that the pupillary light reaction is relatively preserved in the affected eyes of patients with Leber hereditary optic neuropathy (LHON). To test the hypothesis that visual-pupillomotor dissociation exists in LHON, we performed a retrospective study to evaluate the magnitude of the relative afferent pupillary defect (RAPD) in patients who had experienced monocular visual loss. We also compared the size of the measured RAPD with the size of the RAPD that would be expected on the basis of documented visual field loss. METHODS: We identified a cohort of patients with LHON and monocular visual loss, whose pupillary reactions had been quantified using neutral density filters. From a review of the case records, we determined whether an RAPD was present, as well as the magnitude of the documented RAPDs. We also calculated the expected size of the RAPD for each patient, using previously established templates that correlated the size of the RAPD with the degree of visual field loss. RESULTS: An RAPD was identified in all 10 patients in this study. There was no significant difference between the size of the measured and predicted RAPD, nor did the size of the RAPD correlate with visual acuity or the time interval between the onset of visual loss and evaluation. CONCLUSION: The results of this study do not support the hypothesis that visual-pupillomotor dissociation is a common feature of LHON.

Adolescent↗
PubMed1998

Papilloedema, a complication of progressive diaphyseal dysplasia: a series of three case reports.

BACKGROUND/AIMS: Progressive diaphyseal dysplasia (PDD) is a rare, autosomal dominant, osteosclerotic dysplasia affecting both endochondrally and intramembranously derived bones. Severely affected patients can develop progressive stenosis of the optic canals and compressive optic neuropathy. Although raised intracranial pressure (ICP) has been described in patients with PDD in whom visual loss has occurred, the elevation of ICP in those patients has been thought to be either non-contributory or only partially responsible for the accompanying visual loss. METHODS: Three cases were reviewed and the clinical and radiological characteristics are described here. RESULTS: All three patients had bilateral optic disc swelling with no radiological evidence of either compressive optic neuropathy or thrombosis of the intracranial venous sinuses. The aetiology of the disc swelling was proved to be papilloedema in the first two cases and was probably the dominant cause in the third case. CONCLUSION: The visual loss documented in at least two of the three patients reported appears to be solely attributable to raised ICP. Normalisation of the ICP has led to an improvement and stabilisation of the visual function in all three patients. Patients with PDD probably require periodic ophthalmic assessments.

Adult↗
PubMed1998

Vigabatrin-associated retinal cone system dysfunction: electroretinogram and ophthalmologic findings.

OBJECTIVE: To determine the sources of vigabatrin-associated visual disturbances in patients treated for epilepsy. BACKGROUND: Vigabatrin is an extremely effective antiepileptic drug that selectively increases brain gamma-aminobutyric acid (GABA). Several patients recently developed constricted visual fields during vigabatrin treatment in the United Kingdom, indicating the possibility of GABA-associated retinal dysfunction. METHODS: Patients with visual symptoms treated chronically with vigabatrin at our center underwent visual evoked potentials (VEP), electroretinograms (ERG), and visual field and ophthalmologic examinations. RESULTS: Four of 38 patients treated with vigabatrin developed visual symptoms 2 to 40 months after starting the drug. Two patients complained of constricted visual fields and two had blurred vision. ERG demonstrated evidence of bilateral retinal dysfunction consistent with reduced inner retinal cone response in all four patients. Oscillatory potential responses were lost, suggesting impairment of the highly GABAergic amacrine cells. Two of the patients had normal VEPs and minimal findings on clinical ophthalmology examinations despite abnormal ERGs. Abnormal examination findings were narrowed retinal arteries, surface wrinkling retinopathy, and abnormal macular reflexes. One patient also had reduced rod photoreceptor function in the more symptomatic left eye. CONCLUSIONS: Visual field constriction and blurring during vigabatrin therapy is associated with retinal cone system dysfunction. Visual symptoms may represent selective vulnerability of retinas of affected patients to GABAergic effects of vigabatrin. The prevalence and course of retinal changes associated with vigabatrin therapy are important to determine in a larger group of patients.

Adult↗
PubMed1998

Preservation of residual vision 2 years after stereotactic radiosurgery for a presumed optic nerve sheath meningioma.

We performed stereotactic radiosurgery on a patient with a presumed optic nerve sheath meningioma with a progressive optic neuropathy and an intact peripheral visual field. The patient's visual acuity and visual field have remained stable for 2 years following treatment, and the appearance of the tumor has not changed by neuroimaging. We believe that stereotactic radiosurgery is a viable option for treating optic nerve sheath meningioma.

Adult↗
PubMed1998

Pachymeningitis with multiple cranial neuropathies and unilateral optic neuropathy secondary to Pseudomonas aeruginosa: case report and review.

Hypertrophic cranial pachymeningitis is a rare disorder that frequently presents with multiple cranial neuropathies. This disorder, which is characterized by thickening and infiltration of the cranial dura, can result from a variety of inflammatory and infectious conditions. A patient with hypertrophic cranial pachymeningitis is described in whom meningeal biopsy and bacterial cultures of the biopsy specimen revealed Pseudomonas aeruginosa. The authors believe this to be the first documented case of pachymeningitis secondary to this organism.

Ceftazidime↗
PubMed1998

Bilateral internuclear ophthalmoplegia related to chronic toluene abuse.

A 36-year-old woman exhibited slurred speech, progressive ataxia, blurred vision, and oscillopsia. Examination showed dysconjugate torsional nystagmus and bilateral internuclear ophthalmoplegia (INO). Further investigation revealed evidence of chronic toluene abuse. The neurologic findings in toluene abuse and the causes of bilateral INO are discussed.

Adult↗
PubMed1997

Fourth nerve palsy caused by Ehrlichia chaffeensis.

Two human ehrlichioses occur in the United States: human monocytic ehrlichiosis (HME), which is caused by Ehrlichia chaffeensis that infects mononuclear phagocytes in blood and tissue, and human granulocytic ehrlichiosis (HGE), an infection of granulocytes that is caused by a similar but phylogenetically distinct organism. The clinical features of both forms of human ehrlichiosis are identical and include nonspecific constitutional manifestations, such as fever, headache, malaise, nausea, vomiting, myalgia, and anorexia; however, rare patients develop neurologic symptoms and signs. Few cases of human ehrlichiosis have been described in detail, and focal neurologic deficits have only rarely been reported in such cases. We describe a patient with HME who developed a trochlear nerve paresis associated with evidence of lymphocytic meningitis during the course of her illness. We believe this to be the first well-documented case of a focal neurologic complication of human ehrlichiosis.

Adult↗
PubMed1996

Visual field loss following vitreous surgery.

OBJECTIVE: To assess possible causes of visual field loss following vitreous surgery. DESIGN: Charts of 8 patients prospectively identified, who developed visual field loss following vitreous surgery, were reviewed to characterize this newly recognized syndrome and assess possible causes. RESULTS: Two patients had preexisting chronic open-angle glaucoma and 1 had ocular hypertension. Indications for surgery included 4 eyes with macular holes, 1 eye with epiretinal membrane, 2 eyes with rhegmatogenous retinal detachment, and 1 eye with retinal detachment and giant retinal tear. All patients received retrobulbar anesthesia. Seven of 8 patients had fluid/gas exchange with installation of long-acting bubbles. In 1 patient with a macular hole, a small hemorrhage was noted along a vessel coming off the nerve superotemporally while attempting to engage the posterior cortical vitreous intraoperatively. This patient developed an inferior visual field defect. No intraocular pressure (IOP) measurements greater than 26 mm Hg were recorded in any eye perioperatively. Visual field defects included 4 eyes with inferotemporal defects, 2 eyes with inferior altitudinal defects, 1 eye with a cecocentral scotoma, and 1 eye with a superonasal defect. Only 1 patient had worsened visual acuity. A relative afferent pupillary defect was observed in 4 eyes and disc pallor in 5 eyes. CONCLUSIONS: Central or peripheral visual field loss can now be recognized as a possible complication of vitreous surgery. In some cases, a relative afferent pupillary defect and optic disc pallor are present, suggesting that the optic nerve is the site of injury. Possible mechanisms include ischemia due to elevated IOP or fluctuations in IOP, optic nerve damage from retrobulbar injection, direct intraoperative mechanical trauma to the optic nerve, indirect injury from vigorous suction near the optic nerve leading to shearing of peripapillary axons or vessels, or a combination of these. Certain optic nerves may be more susceptible to injury because of preexisting compromise from glaucoma or vascular disease.

Adult↗
PubMed1996

Three cases of spontaneous direct carotid cavernous fistulas associated with Ehlers-Danlos syndrome type IV.

We are reporting three cases of spontaneous direct carotid cavernous fistulas (CCFs) associated with Ehlers-Danlos syndrome (EDS) out of a series of 147 direct CCFs. The internal carotid artery could be preserved in only one case. Two patients had severe bilateral irregularities of caliber of both internal carotid arteries. Two patients had recurrence of their symptoms after a first balloon was detached in the cavernous sinus (CS) necessitating a second treatment. Two patients died several months later from complications associated with their disease. The treatment of direct CCFs associated with Ehlers-Danlos syndrome is more difficult and more risky than most direct CCFs. The permanent occlusion of the ICA, which may be difficult to avoid, increases the risks of development of aneurysm on the contralateral side.

Adult↗
PubMed1996

Pneumosinus dilatans: a sign of intracranial meningioma.

BACKGROUND: Pneumosinus dilatans affecting the sphenoid and posterior ethmoid sinuses has been reported in association with spheno-orbital meningiomas and is believed by some authors be a sign of an adjacent meningioma. METHODS: We report the case of a 57-year-old man who developed progressive neurologic signs and symptoms consistent with a frontal lobe lesion. Neuroimaging studies revealed a large partially cystic mass at the base of the anterior cranial fossa that appeared to be invading the left frontal lobe and that was associated with pneumosinus dilatans of the adjacent left frontal sinus. RESULTS: Although the appearance of the mass by neuroimaging was thought to be most consistent with a malignant glioma, the lesion was found at craniotomy to be a benign meningothelial meningioma. CONCLUSIONS: Many previous cases of progressive optic neuropathy associated with pneumosinus dilatans affecting the sphenoid and posterior ethmoid sinuses have been found to be caused by adjacent optic nerve sheath meningiomas. This case provides further evidence that pneumosinus dilatans is a sign of intracranial meningioma.

Humans↗
PubMed1996

Posterior ischemic optic neuropathy associated with migraine.

Anterior ischemic optic neuropathy is a well-recognized clinical syndrome that has been described in patients after an episode of migraine with visual aura (classic migraine) and, less commonly, after an episode of visual aura without headache (acephalgic migraine). Little emphasis, however, has been placed on migraine-associated retrobulbar or posterior ischemic optic neuropathy. We report two cases of visual loss presumed to be due to posterior ischemic optic neuropathy that occurred in the setting of otherwise typical migraine episodes. We review the English language literature on ischemic optic neuropathy associated with migraine. Although most cases of ischemic optic neuropathy associated with migraine are of the anterior variety, posterior ischemic optic neuropathy should be considered in the differential diagnosis of any patient with acute loss of vision and evidence for a retrobulbar optic neuropathy, during or after an attack of migraine headache or following an otherwise typical episode of visual aura without headache (acephalgic migraine).

Adult↗
PubMed1996

The optic nerve.

Recent articles in the scientific literature have described major advances in our understanding of the anatomy and vascular relationships of the optic nerve (cranial nerve II) and of the diagnosis and treatment of a variety of disorders affecting this nerve, including congenital anomalies of the optic disc, dominant hereditary optic neuropathy, anterior and retrobulbar arteritic and nonarteritic ischemic optic neuropathy, optic neuritis, Cuban epidemic optic neuropathy, toxic and nutritional optic neuropathies, radiation-induced optic neuropathy, AIDS-related optic neuropathy, optic neuropathies caused by tumors, and papilledema.

Humans↗