Neuro-Ophthalmology

Lyme disease is a multisystem disorder caused by infection with the Borrelia burgdorferi spirochete. The diagnosis of Lyme disease usually is based on several clinical criteria, with supportive data from laboratory testing. The presence of the bullseye skin lesion, erythema migrans, is the single pathognomonic criterion. In the 20 years since the initial description of Lyme disease in the United States, B. burgdorferi has been implicated as an etiologic agent in numerous ophthalmic and neuro-ophthalmic syndromes, involving most structures from the cornea to the cranial nerves. Neuro-ophthalmic and ocular manifestations of Lyme disease include meningitis with papilledema, cranial neuropathies, follicular conjunctivitis, nummular keratitis, and intraocular inflammation. Although an association with Lyme disease has been purported for numerous other syndromes, a definite causal relationship has not been proved in many cases. During a period of rapidly increasing awareness of Lyme disease, a high index of suspicion and poorly defined criteria for its presence have resulted in over-diagnosis of Lyme disease. In the authors' experience, the incorrect diagnosis of Lyme disease initially has been made in patients with allergic conjunctivitis, keratoconus, morning glory syndrome, craniopharyngioma, meningioma, CNS lymphoma, paraneoplastic syndrome, multiple sclerosis, sarcoid, syphilis, and functional illness. Nevertheless, this treatable infection must be an important consideration in the differential diagnosis of certain ocular or neurologic diseases.

Authors' abstract, J Neuro-ophthalmol
Hospital of the University of Pennsylvania,
Philadelphia,PA

Neuro-Ophthalmology

PURPOSE: To report bilateral congenital optic nerve head pits in monozygotic siblings.

METHOD: Case reports.

RESULTS: Pits were found in abnormally large optic disks in both eyes of two otherwise healthy female monozygotic siblings aged 15 years. Pit size increased and visual acuity decreased with increased optic disk area. In one eye, nonrhegmatogenous retinal detachment developed that eventually necessitated pars plana vitrectomy. The siblings' parents were unremarkable.

CONCLUSIONS: Congenita optic nerve head pits can occur bilaterally in otherwise healthy monozygotic siblings with ophthalmologically unremarkable parents. Associated nonrhegmatogenous retinal detachment may be treated by pars plana vitrectomy. Pit size is positively correlated with disk area.

Authors' abstract, AJO
Friedrich-Alexander-University Erlangen-Nurnberg.

Neuro-Ophthalmology

Objective:
Diplopia is not frequently associated with Arnold-Chiari I malformation. We reviewed our cases of Arnold-Chiari I malformation in which acquired esotropia with diplopia was the main neuro-ophthalmologic finding early in the clinical course.

Materials and Methods:
Five patients were studied, all female, ranging in age from 17 to 36 years, who were treated by the neuro-ophthalmology service of urban teaching hospitals. Eye movement recordings using magnetic search coil technique were performed in two patients.

Results: All patients reported onset of horizontal diplopia due to acquired esotropia as an initial manifestation of the Arnold-Chiari I malformation. All had full abduction of each eye. In addition, all five had gaze-evoked nystagmus, two skew deviations, and one bilateral internuclear ophthalmoparesis. Oculography in two patients showed normal abducting saccadic peak velocities. This supports divergence palsy as a mechanism of acquired esotropia and provides evidence against subtle sixth nerve palsy in these patients. Four patients underwent neurosurgical decompression of their Chiari malformations, and neuro-ophthalmologic signs and symptoms improved in all.

Conclusions: Acquired esotropia, often in association with other eye movement abnormalities, may be an early sign of Arnold-Chiari I malformation. This quantitative study indicates that divergence palsy is the cause of esotropia in some patients. Neurosurgical suboccipital and upper cervical decompression may lead to improvement or resolution of diplopia.

Authors' abstract, JNO
Birmingham, AL

Neuro-Ophthalmology

BACKGROUND:
A lesion affecting the optic radiations may produce a quadrantanopia based on the topographical arrangement of the geniculocalcarine tract.

OBJECTIVE:
To determine the localizing associations of a quadrantic visual field defect.

DESIGN:
Retrospective study of case records of 41 patients with inferior quadrantanopia and 30 patients with superior quadrantanopia caused by disorders affecting the posterior visual pathway. The responsible lesion was identified with neuroimaging techniques.

SETTING:

Neuro-ophthalmology referral practice in a large multispecialty clinic that provides primary, secondary, and tertiary medical care.

RESULTS:

Cerebrovascular disorders accounted for most lesions. The location (and frequency) of lesions causing inferior quadrantanopia was occipital lobe (76%), parietal lobe (22%), and temporal lobe (2%). Other localizing signs were associated with 6%, 89%, and 0% of lesions located in the occipital, parietal, and temporal lobes, respectively. The location (and frequency) of lesions causing superior quadrantanopias was occipital lobe (83%), parietal lobe (3%), and temporal lobe (13%). Other localizing signs were associated with 4%, 100%, and 0% of lesions located in the occipital, parietal, and temporal lobes, respectively.

CONCLUSIONS:
A patient with a neurologically isolated quadrantanopia is likely to have a lesion in the occipital lobe, although, in the case of a superior quadrantanopia, the possibility of a temporal lobe lesion can not be excluded using clinical criteria only. Quadrantanopias caused by lesions of the parietal lobe usually are associated with other localizing signs.

Author's abstract, Arch Neurol
Marshfield Clinic, Wisconsin

Neuro-Ophthalmology

Cutaneous carcinomas of the face, and some nasopharyngeal carcinomas, may present with facial dysesthesias and/or facial nerve palsies in the absence of visible masses. Even with frank ophthalmoplegia, occult tumors that present in this matter may elude detection, for which reason specific diagnostic studies must be employed. We report seven cases of trigeminal nerve infiltration by occult tumors (five squamous cell carcinomas, one basal cell carinoma, and one adenoid cystic carcinoma), and outline the clinical course, diagnostic investigations, and the subsequent managementof these patients. The importance of establishing an early diagnosis before the tumor has transgressed the basal foramina is emphasized, as tumor infiltration of the cavernous sinus carries a more guarded prognosis. The use of magnetic resonance imaging to identify involved peripheral nerve branches that may then be biopsied is suggested. The pathophysiological mechanisms of neurotropic spread of tumor are reviewed.

Author's abstract, JNO
Kingston, Ontario

Neuro-Ophthalmology

A 42-year-old immune-competent woman with orbital pseudotumor and presumed intracranial extension into the temporal lobe responded well clinically and radiologically to high-doses of corticosteroids. Five months later, she developed worsening headaches and recurrence of the temporal lobe lesion. Biopsy revealed a central nervous system (CNS) lymphoma with severe reactive gliosis abutting an area of subarachnoid lymphocytic infiltrate.

Authors' abstract, JNO
Doheny Eye Institute,
Los Angeles, CA