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Biomedical subjects

K Landau

Publications and source records attributed to K Landau.

At least 19 recordsLinked to original sources
PubMed1998

Topless optic disks in children of mothers with type I diabetes mellitus.

PURPOSE: To determine the prevalence of and risk factors for superior segmental optic nerve hypoplasia in offspring of mothers with type I diabetes mellitus. METHODS: Thirty-four subjects aged between 4 and 37 years, the children of 23 mothers who had type I diabetes mellitus at the time of pregnancy, aged between 4 and 37 years, were recruited from one institution and prospectively examined in search of an optic disk-related anomaly. RESULTS: Of the 34 subjects, three females (8.8%) showed classic ophthalmoscopic and perimetric features of superior segmental optic nerve hypoplasia, bilateral in two patients and unilateral in one. Pregnancies leading to affected children showed a tendency to be shorter, birth weight to be lower, and control of maternal diabetes mellitus to be poorer compared with pregnancies resulting in unaffected children. No variable unique to the affected subjects as opposed to the unaffected majority could be identified. CONCLUSIONS: We found a superior segmental optic nerve hypoplasia, described as a "topless disk," in three of 34 subjects (8.8%) at risk for this condition. Topless disk thus seems to be more common than was previously thought, possibly having been missed because of its subtle signs and only mild impairment of visual performance in affected individuals. Female sex, short gestation time, low birth weight, and poor maternal diabetes control may represent additional risk factors for the development of a topless disk. Its pathogenesis remains obscure, but the responsible pathogenic event may occur in the perinatal period.

Adolescent↗
PubMed1998

Functional evaluation using magnetic resonance imaging of the visual cortex in patients with retrochiasmatic lesions.

OBJECT: The goal of this study was to evaluate the clinical potential of combining functional magnetic resonance (fMR) imaging with conventional morphological MR imaging and to assess its usefulness for objective evaluation of visual function as part of treatment planning in patients harboring space-occupying lesions involving the posterior afferent visual system. METHODS: It was hypothesized that regional activation of the visual cortex during visual stimulation would show an asymmetric response consistent with the well-known retinotopical organization of the human visual cortex. To test this hypothesis, the pattern of regional cortical activity detected by fMR imaging during binocular repetitive photic stimulation (10 Hz) was compared with the findings of conventional visual field testing. Functional mapping of the visual cortex was performed using a noninvasive blood oxygen level-dependent MR technique in 10 patients with intraaxial and two with extraaxial lesions. Experiments involving two of the patients were unsuccessful because of motion artifacts. In all the remaining patients functional activity was demonstrated in the primary visual area that corresponded to the anatomical location of the calcarine cortex. In nine patients, the identified patterns of activation in the visual cortex were consistent with the visual field deficits (seven homonymous hemianopsias, one homonymous central scotoma, and one inferior quadrantanopsia) and with the traditional teaching of retinotopical representation. Discordance between fMR imaging and perimetric findings was observed in one case. CONCLUSIONS: These results demonstrate that fMR imaging can be performed routinely and successfully in patients with visual abnormalities as part of a conventional neuroradiological evaluation. The technique provides essential information about the function-structure relationship specific to an individual patient and holds promise not only for diagnosis and therapy planning, but also for understanding the topography and functional specialization of the human visual cortex.

Adult↗
PubMed1998

[Computer-assisted stress analysis in rehabilitation with ABBA (job requirements and capacity analysis)].

ABBA is a recently devised, ergology-based expert system software for vocational analysis, documentation and evaluation--inter alia in the context of medical and vocational rehabilitation-, drawing on some 20 years of experience in job analysis with the AET (Arbeitswissenschaftliches Erhebungsverfahren zur Tätigkeitsanalyse). Designed for broad and differentiated coverage, a PARADOX data bank comprising the entire data collected enables comparison of job requirements and client performance potential, reaching for beyond individual analysis on account of its integration of job profiles for a given industry or occupation, or for an entire company. The related, and easy-to use, software for data processing and appraisal is now being made available by ABBA along with dialogue-based ergological know-how.

Diagnosis, Computer-Assisted↗
PubMed1997

Follow-up in children with Joubert syndrome.

Although Joubert syndrome (JS) was first reported in 1969 by Joubert et al (21), the long-term outcome is not yet documented. We report 19 children (4 pairs of siblings) from a single institution diagnosed with JS. Nine children were last seen between ages 10 and 18 years, seven between ages 1 and 4 years. Three children died before 3 years of age, showing marked breathing problems and minimal development. The 16 surviving children showed variable motor development, walking was typically achieved between 2 and 10 years, two children did not learn to walk. Cognitive development showed four with development quotient (DQ) of 30 or less and nine with DQ of 60-85, the others could not be judged confidently. Siblings did not show similar development and sex was not predicting outcome. The following oculomotor problems were seen: mystagmus in 11, ocular motor apraxia in six, isolated ptosis in two, and vertical gaze palsy in three. Additional features were retinal involvement in eight and kidney involvement in four, in one of them after normal previous ultrasound. In conclusion development of children with JS can be split into distinct subgroups, with one group dying at a young age. Those who survive show variable motor and cognitive development and can be grouped into those with DQ of less than 30 or those with DQ between 60 and 85. Ophthalmological and renal involvement may change or develop over the years and should be followed carefully.

Adolescent↗
PubMed1996

[The bane of giant cell arteritis from an ophthalmological viewpoint].

We report a series of 21 consecutive patients seen at the Ophthalmology Department of the University Hospital Zurich, Switzerland, with the arteritic form of anterior ischemic optic neuropathy (AION). 19 patients had giant cell arteritis, one had periarteritis nodosa and one had cP-arteritis. They comprised 11 men and 10 women, ranging in age between 66 and 88 years. The median age was 80. We analyzed the course of events in each case before and after involvement of the first eye, as well as the frequency and possible causes of involvement of the second eye. The diagnosis was regarded as delayed when, despite typical signs, symptoms amd laboratory abnormalities, systemic vasculitis was not considered in the differential diagnosis. Treatment was considered inadequate if, following visual loss in one eye and diagnosis of a systemic vasculitis, a dose of 1 mg/kg prednisone or less was given, and/or the initial dose was reduced by more than 50% during the first month. Of 21 patients, 10 suffered bilateral visual loss. 8 of these 10 patients became legally blind. In 13 out of 21 cases there was no delay in diagnosis and treatment was adequately given. All 11 patients with unilateral involvement, who did not suffer a substantial loss in quality of life, belong to this subgroup. In 8 cases diagnosis was either delayed or treatment was inadequate. All of these patients had bilateral ocular involvement. In one patient, visual loss in the second eye could not be avoided despite correct diagnosis and treatment (M.A., No. 1). In this patient the interval between involvement of the first and second eye was very short (3 days). One patient had a mature cataract in the first affected eye and sought medical help only after his good eye became involved (K. F., No. 15). In this report we would like to draw attention to the extremely poor visual prognosis due to frequent bilateral ocular involvement in giant cell arteritis. Corticosteroid treatment cannot restore vision in the already affected eye, but it is, in the majority of cases, highly effective in preventing visual loss in the second eye. Thus, it is crucial to begin treatment immediately, to start with a high dose (preferably 1 g methyl-prednisolone i.v.), and to continue high-dose oral treatment long enough to prevent delayed visual loss in the second eye. The most vulnerable period appears to be the first month following involvement of the first eye. Caring for patients with giant cell arteritis who have lost vision in one eye is a challenge to all involved physicians. It resembles a "high-wire act" with the threat of blindness on the one hand and the dangers of long term corticosteroid treatment on the other. An interdisciplinary approach with ongoing communication between the family physician and the ophthalmologist is required.

Aged↗
PubMed1996

[Increasing vision disorder].

A 62-year-old patient complained about slowly increasing, intermittent vision disorders. Ophthalmologic investigation revealed choked disks in both eyes. A neurologic investigation performed thereafter disclosed increased cerebrospinal fluid pressure without recognizable cause. Internistic investigation was inconspicious; in particular, there were no indications for a systemic disease. The distinct findings of choked disks on both sides and increased cerebrospinal fluid pressure without detectable organic causes finally lead to the diagnosis of benign intracranial hypertension or pseudotumor cerebri. Not until the nerve sheath of the right optic nerve was split did the visual field defects in the right eye diminish. Splitting of the left optic nerve sheath is planned.

Humans↗
PubMed1996

24-hour blood pressure monitoring in patients with anterior ischemic optic neuropathy.

OBJECTIVE: To define parameters of ambulatory diurnal blood pressure in patients who had experienced anterior ischemic optic neuropathy (AION) in a case-controlled study. PARTICIPANTS AND METHODS: Twenty-four patients with AION and 24 control subjects who were matched for age, gender, medical diagnoses, and medications underwent ambulatory automated blood pressure monitoring for 24 hours. RESULTS: The overall diurnal pattern of blood pressure appeared to be normal in all subjects, showing lower blood pressures at night than during the day, an overnight nadir, and an ascending blood pressure curve in the morning to reach daytime levels. Also, patients with AION did not differ from control subjects with respect to the nighttime diastolic nadir or daytime peak systolic blood pressure. However, during the daytime, patients with AION had lower mean systolic and diastolic blood pressures than did matched control subjects. The widest difference between their blood pressure curves occurred after awakening in the morning, when patients with AION had a less steep and more irregular rise of blood pressure. Patients who had signs of vertebrobasilar insufficiency in addition to AION had lower mean diastolic blood pressure during both daytime and nighttime and a lower minimum daytime diastolic blood pressure. CONCLUSIONS: On ambulatory measurements of diurnal blood pressure, patients with AION consistently had a lower mean blood pressure than did control subjects and a lag in the usual rise in blood pressure in the morning to meet increasing daytime demands for perfusion. Chronic hypoperfusion of small end-arterial vessels that supply the optic nerve head may predispose to AION, and may be caused by relative hypotension owing to overtreated hypertension or to abnormal vascular autoregulation. Internists should be asked to monitor blood pressure carefully when treating hypertensive patients who are at risk for AION, to avoid hypotension, especially on awakening in the morning.

Aged↗
PubMed1996

Cerebral tuberculosis presenting as complex febrile convulsions.

Complex febrile convulsions were the initial clinical manifestation of miliary tuberculosis in a 4-year-old immigrant girl. The cerebral lesions were visible only after contrast-enhanced cranial computed tomography (CT) while native CT scan as well as cell count and glucose concentration in the cerebrospinal fluid were normal. Mycobacterium tuberculosis was cultured from gastric aspirate and liver biopsy tissue. Treatment with isoniazid and rifampin for 12 months, pyrazinamide for 9 months, and ethambutol for the initial 6 weeks resulted in resolution of the cerebral lesions but a retinal scar after granuloma formation in the right eye caused reduced visus. This case demonstrates the importance of thorough search for tuberculosis even in the absence of overt clinical pulmonary signs especially in high-risk individuals such as immigrants.

Antitubercular Agents↗
PubMed1995

The missing temporal crescent.

PURPOSE: We studied clinically the representation of the monocular temporal crescent in the human visual cortex and noted the importance of using the perimetric techniques best suited to detect this visual field defect and to study patients in whom the temporal crescent is missing. METHODS: Goldmann perimetry and high-resolution magnetic resonance imaging were performed in two patients with vascular lesions located in the anterior striate cortex. RESULTS: A monocular visual field defect, the missing temporal crescent, was found on the side contralateral to the lesion. CONCLUSIONS: The perimetric-magnetic resonance imaging correlation is in exquisite agreement with recent information about the representation of the visual field in the human primary visual cortex. Reports of this specific perimetric finding are rare, in part because of underdetection with currently used perimetric techniques that concentrate on the central 30 degrees of the visual field.

Adult↗
PubMed1994

Follow-up of optic pathway gliomas in children with neurofibromatosis type 1.

Optic pathway gliomas (OPG) are found in about 15% of patients with neurofibromatosis Type 1 (NF-1). The natural history of OPG is not yet well documented. Treatment in cases with growing tumors is still controversial. Twenty-one patients with NF-1 and OPG, diagnosed over a 20-year period, and followed neuroradiologically and ophthalmologically for at least two years, were reevaluated. The diagnosis of OPG was made at a mean age of 7.1 years (range 0-14.5 years); six children were asymptomatic, 15 were symptomatic. The mean follow-up was 9.0 years (2.0-18.5 (years). In eight initially operated or biopsied patients (three optic nerve and five chiasmal gliomas) tumor regrowth was found in one patient without progression on subsequent follow-up. Improvement of visual acuity occurred in one child after operation of a large suprasellar tumor and deterioration in one patient after biopsy of a chiasmal glioma. The neuroradiological follow-up of the 13 not-operated and not-radiated patients (four optic nerve and nine chiasmal gliomas) was stable in 10, progressive in three, resulting in visual loss in one patient. In 11 children (52%) a second tumor outside the optic pathway was found at a mean age of 4.0 years after the diagnosis of an OPG. Until now they are mostly asymptomatic. Second site tumors were operated in two children because of rapid tumor growth, one child died of a brainstem tumor. OPG are a frequent complication in children with NF-1, appearing within the first decade.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Therapy-resistant papilledema in achondroplasia.

A 20-year-old achondroplastic dwarf developed severe papilledema over a short period of time. Since the age of 3 he had a ventriculoperitoneal shunt for presumed hydrocephalus. Severe ventriculomegaly was never documented, neither in the past, nor at presentation. Intracranial pressure was high, and the shunt was obliterated. Despite prompt shunt revision and subsequent bilateral optic nerve sheath decompression the patient developed postpapilledema optic atrophy with bilateral blindness. The pathophysiology of increased intracranial pressure in achondroplasia is discussed.

Achondroplasia↗
PubMed1993

[Evaluation of visual field defects, motility disorders and diplopia within the scope of accident insurance law].

Visual Field: The determination of the level of compensation for loss of integrity is based on the Goldmann Perimetry. In case of concentric loss of the visual field the SUVA Tables 1989 are used. Hemi- and Quadrantanopsias are still evaluated according to the Rintelen Tables from 1954. No guidelines are available for the evaluation of central and paracentral skotomas. It is uncertain if automatic perimetry can be used routinely in the future for the evaluation of visual function. Motility Disorders and Diplopia: The evaluation of functional loss caused by diplopia is very difficult. Therefore a big variation of 5-30% has been determined. It is up to the specialist to evaluate the extent of the damage. In this study we looked for a correlation between the objective findings and the subjective complaints. Such a correlation could not be found so that an arbitrary classification depending on the extent of the diplopia must be recommended. This would create an analogy to the evaluation of the loss of visual acuity and visual field where no freedom is left to the judgement of the physician. Some reflections are given on the sense and benefit of the unique Swiss law concerning compensation for loss of integrity.

Diplopia↗
PubMed1993

Ocular fundus in neurofibromatosis type 2.

Several ocular findings have been associated with neurofibromatosis type 2 (NF 2) since the identification of this disease as a distinct clinical entity. Juvenile cataracts were reported first, followed by combined pigment epithelial and retinal hamartomas. In a recent report, epiretinal membranes were described in seven of nine patients. Moreover, an association between NF 2 and optic disc gliomas has been suggested based on earlier published reports. Six patients with a confirmed diagnosis of NF 2 were examined. Four patients (six of 12 eyes) had epiretinal membranes and one had an optic disc glioma. In addition, one case of an optic disc glioma in a patient with NF 2 was tracked. It is concluded that epiretinal membranes are frequent in NF 2, and that optic disc glioma is a rare but specific sign of NF 2. Patients at risk for development of this disease should undergo careful examination of the ocular fundus.

Adult↗