Klin Monbl Augenheilkd
January 1998
Background: Multifocal electroretinography allows simultaneous recording of 61 focal electroretinographic signals from the retina of the posterior pole. The function of the outer retinal layers can be mapped for a visual field of 30.5 degrees radius.
View Article and Find Full Text PDFSpontaneous pupillary-behavior in darkness provides information about a subject's level of sleepiness. In the present work, pupil measurements in complete darkness and quiet have been recorded continuously over 11-minute period with infrared video pupillography at 25 Hz. The data have been analyzed to yield three parameters describing pupil behavior; the power of diameter variation at frequencies below 0.
View Article and Find Full Text PDFPurpose: The purpose of the study was to detect and safely diagnose pneumatocysts by means of computed tomography.
Methods: From September 1995 to May 1996 computed tomography of the pelvis was performed in six patients for various indications. A slice thickness of 8 mm was employed for all studies.
Eur Neuropsychopharmacol
August 1997
Patients taking anticonvulsant drugs display a broad spectrum of side-effects. Particularly, in the beginning of treatment and with increasing doses of carbamazepine, side effects such as dizziness, ataxia, drowsiness and reduction of alertness occur, which improve some days after the dose has reached a stable level. Our aim was to find objective parameters for grading these side effects and to differentiate between neurophysiological and neuropsychological side effects of carbamazepine in a clinical situation.
View Article and Find Full Text PDFKlin Monbl Augenheilkd
June 1997
Unlabelled: The purpose of this study was to test for correlation between relative afferent pupillary defect (RAPD) and visual acuity, central differential light threshold and visual field defect measured by suprasthreshold automated grid perimetry.
Methods: In 98 patients with optic neuropathies of different origin (inflammatory, ischemic, or compressive) in addition to a standard ophthalmological examination, static perimetry of the 30 degrees visual field with a dense grid of test spots, including measurement of the central differential light sensitivity, was done by means of the Tübingen Automated Perimeter. RAPD was tested using the swinging flashlight test quantified with neutral density filters.
Background And Purpose: There are several possible sources of cerebral embolic ischaemia distal to an occlusion of the internal carotid artery (ICA). Our aim was to identify the source of microembolic signals in the ipsilateral middle cerebral artery (MCA) by taking simultaneous bitemporal transcranial Doppler ultrasound recordings of the ipsilateral MCA and the contralateral ACA to find the route of potential microembolic material to MCA.
Subjects And Methods: The study group consisted of 38 patients with an occlusion of the ICA.
To measure vigilance disorders in healthy normals or in patients (narcolepsy, sleep apnea syndrome) is difficult, time-consuming and hardly objective with present methods. Recording and analysis of spontaneous pupillary behaviour in darkness by infrared video pupillography is an objective and time-saving method to measure daytime sleepiness. However, certain external conditions must be satisfied (avoid light, noise, stress) to get reliable results.
View Article and Find Full Text PDFClassically, the pathway serving the pupillary light reflex is considered to be a simple reflex arc consisting of the retinal ganglion cells, intercalated neurons in the midbrain, the oculomotor nerve and short ciliary nerves. Investigations in patients with lesions of the postgeniculate visual pathways showed that the pupillary pathway is more complex than previously assumed. The retrogeniculate visual pathway is also involved in the pupillary light reaction.
View Article and Find Full Text PDFIn suspected Horner's syndrome, cocaine eye drops are applied to verify the diagnosis. Subsequent application of hydroxyamphetamine or pholedrine eye drops allows localization of the site of the interruption in the oculosympathetic pathway. In the present study the influence of cocaine on subsequent pholedrine testing was examined.
View Article and Find Full Text PDFDerived from models of neural networks, a model for the pupillary pathway is introduced that can easily be handled computationally and analytically. To model the binocular pupillary reactions we use a feed-forward network, namely, a multi-layered perception. It is possible to calculate the pupillary reactions analytically as a function of the light stimuli of the retinal hemifields, on the one hand, and the set of neural couplings between the neural layers, on the other.
View Article and Find Full Text PDFKlin Monbl Augenheilkd
March 1996
A 49-year-old patient suffered from a binocular perforating trauma with metal foreign bodies in 1974. During an MRI examination in 1992 for a lumbar spine herniation a metal foreign body was mobilised from the deeper vitreal and retinal area, now causing optical disturbances freely floating in the anterior vitreous. Refusing an operation, the patient, an electrical engineer, tried himself to remove the foreign body out of the optical axis by exposing his head to the electro-magnetic field of an induction coil (pulsed magnetic induction B at t0 of 0.
View Article and Find Full Text PDFInfrared video pupillography (IVP) allows continuous recording of spontaneous pupillary oscillations in darkness which change characteristically with fatigue. Pupil size in darkness is age-related, has its maximum in the second decade and subsequently decreases during life time. Normally, the pupil oscillates in darkness with a frequency of about 1 Hz and amplitudes of less than 0.
View Article and Find Full Text PDFEugen Bleuler's letter of recommendation for Carl Gustav Jung's appointment as a lecturer In January 1905, Eugen Bleuler (1857-1939) wrote a letter of recommendation to the Medical Faculty of the University of Zurich, urging them to accept the application of Carl Gustav Jung (1875-1961) as a lecturer there. Bleuler's letter mentions the contribution to Jung's writing made by Franz Riklin (1878-1938), although he does not define it precisely. It is safe to say that, judging from the way in which Bleuler expresses his opinions in this letter, this may be regarded at the very least as an early sign of his receptiveness to the psychoanalytical ideas of the time.
View Article and Find Full Text PDFThis paper presents three case reports as a basis for discussing the differential diagnosis of retroperitoneal processes and for describing the possibilities and limitations of diagnostic imaging procedures. A definitive differentiation is not possible by CT and MRI alone, but always requires histologic confirmation. Nevertheless, imaging procedures are indispensable for assessing the extent of a lesion and for follow-up.
View Article and Find Full Text PDFInt Angiol
December 1995
Two-dimensional ultrasound is a widely used technique for the clinical assessment of carotid atherosclerosis. We measured volumes of atherosclerotic plaques in carotid arteries in 70 patients with a newly developed and tested three-dimensional ultrasound method over a period of twelve months to determine the relation between progression or regression of plaque volume and vascular risk factors. In multiple regression analysis of age, size, smoking, total cholesterol, HDL-cholesterol, HDL/total cholesterol ratio, LDL-cholesterol, triglycerides, HbA1, diastolic and systolic blood pressure, the strongest predictor of plaque progression (p < 0.
View Article and Find Full Text PDFKlin Monbl Augenheilkd
November 1995
History And Clinical Data: A 67-year-old woman experienced acute unilateral visual loss accompanied by pain with eye movements. There was a marked relative afferent pupillary defect and a nerve fiber bundle defect in the upper half of the visual field. Optic discs were normal.
View Article and Find Full Text PDFBackground And Purpose: Investigations regarding arteriosclerosis of carotid arteries showed an association between increased intima-media thickness and vascular risk factors. A newly developed three-dimensional ultrasound method increases the reproducibility of plaque volume measurements because more exact volume measurements can be performed with a reduction of the disadvantages of two-dimensional measurements. In a pilot study the influence of vascular risk factors on carotid artery plaque progression was examined.
View Article and Find Full Text PDFPatients with circumscribed visual field defects are able to perceive the scotomata immediately while looking at randomly distributed black and white squares (12' x 12') flickering on a VDU with a high frequency (approximately 30 Hz), resulting in a stimulus field comparable to the white-noise field on a TV screen without reception. In 368 eyes of 368 patients with varying lesions of the visual pathway the results of white-noise field campimetry were compared with those of conventional threshold-related, slightly suprathreshold automated grid perimetry. Rate of detection (sensitivity) was 84.
View Article and Find Full Text PDFOphthalmologe
February 1995
A new transportable miniaturized flicker test equipped with green LEDs is contrasted with the conventional Tübingen flicker test, based on brightness perception of intermittent white light. The results are compared with those of former studies. In this study we examined 45 eyes suffering from florid optic neuritis.
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