Peter Wanger

A 5‐year follow‐up study of disease incidence in men with an abnormal hormone pattern

Abstract Rosmond R, Wallerius S, Wanger P, Martin L, Holm G, Björntorp P (The Cardiovascular Institute, Sahlgrenska University Hospital, Göteborg; and Huddinge University Hospital, Huddinge; Sweden). A 5‐year follow‐up study of disease incidence in men with an abnormal hormone pattern. J Intern Med 2003; 254: 386–390.

Early detection of macular changes in patients with diabetes using Rarebit Fovea Test and optical coherence tomography

Aim: To evaluate central retinal thickness and foveal function using optical coherence tomography (OCT) and the Rarebit Fovea Test (RFT) in patients with diabetes without previously known retinopathy or maculopathy. Method: Forty-two patients with diabetes mellitus (DM) were selected from the screening records at St Erik Eye Hospital. Inclusion criteria were absence of macular or other retinal changes at previous screening examination and best corrected visual acuity ⩾1.0. These patients and 42 healthy controls were examined with the recently developed RFT, and retinal thickness was measured using OCT. Lens thickness and light scatter were evaluated by Scheimpflug photography. Results: Significantly more DM subjects (12/42) had a subnormal RFT result compared with the controls (2/42) (p = 0.007). None of the 12 DM subjects had maculopathy, one had mild non proliferative diabetic retinopathy, and five had minimal non-proliferative diabetic retinopathy. The retinal thickness in the pericentral zone was significantly (p<0.05) thinner in DM patients with subnormal RFT compared with the controls. Conclusion: Decreased RT and subnormal RFT results were found in a subgroup of diabetes patients, despite normal screening results. Prospective studies are under way to evaluate the prognostic implications.

New perimetric techniques: a comparison between rarebit and frequency doubling technology perimetry in normal subjects and glaucoma patients.

Purpose:To compare rarebit microdot perimetry (RB) with frequency doubling technology (FDT) perimetry in normal subjects and a group of patients with ocular hypertension or glaucoma, with age-matched controls. Materials and Methods:Eighty-one subjects (age 17–88 years) were examined. Twenty-seven of these were patients, aged 50 to 88 years, with ocular hypertension or suspected/manifest glaucoma in at least one eye. All subjects were examined with the RB and FDT perimetry, using the standard procedures, recommended by the respective manufacturer. Results:All patients were able to perform the RB perimetry, but three patients could not perceive the strongest FDT stimulus. The concordance in RB and FDT classifications as normal/outside normal limits was 96% (Cohens kappa = 0.90). A curvilinear (quadratic) relationship (Rsq = 0.75) was found between RB hit rate and FDT MD. All patients, who could perform both examinations, preferred the RB perimetry. Conclusion:In the current study, the information from the RB and FDT perimetry was almost completely equivalent. However, RB perimetry was preferred by the patients and seemed to have a larger dynamic range than FDT. The RB hit rate is apparently a straightforward and efficient measure of visual field function.

Automated quality evaluation of digital fundus photographs

Purpose:  Retinal images acquired by means of digital photography are often used for evaluation and documentation of the ocular fundus, especially in patients with diabetes, glaucoma or age‐related macular degeneration. The clinical usefulness of an image is highly dependent on its quality. We set out to develop and evaluate an automatic method of evaluating the quality of digital fundus photographs.

Macular changes in diabetic patients with no or mild retinopathy

Aim: To evaluate central retinal thickness and foveal function using optical coherence tomography (OCT) and the Rarebit Fovea Test (RFT) in patients with diabetes without previously known retinopathy or maculopathy. Method: Forty-two patients with diabetes mellitus (DM) were selected from the screening records at St Erik Eye Hospital. Inclusion criteria were absence of macular or other retinal changes at previous screening examination and best corrected visual acuity ⩾1.0. These patients and 42 healthy controls were examined with the recently developed RFT, and retinal thickness was measured using OCT. Lens thickness and light scatter were evaluated by Scheimpflug photography. Results: Significantly more DM subjects (12/42) had a subnormal RFT result compared with the controls (2/42) (p = 0.007). None of the 12 DM subjects had maculopathy, one had mild non proliferative diabetic retinopathy, and five had minimal non-proliferative diabetic retinopathy. The retinal thickness in the pericentral zone was significantly (p<0.05) thinner in DM patients with subnormal RFT compared with the controls. Conclusion: Decreased RT and subnormal RFT results were found in a subgroup of diabetes patients, despite normal screening results. Prospective studies are under way to evaluate the prognostic implications.

Early diagnosis of retinal changes in diabetes: A comparison between electroretinography and retinal biomicroscopy

Abstract. The present study was undertaken in order to find out whether electroretinographic examinations could reveal signs of functional abnormalities before morphological changes are detected in the diabetic retina. Pattern‐reversal and flash electroretinograms (ERG) and oscillatory potentials (OP) were recorded in 24 diabetics and 10 age‐matched normal controls. The diabetic group consisted of 11 patients without retinopathy and 13 patients with background retinopathy. No significant changes in pattern‐reversal or flash ERG or OP amplitudes were observed in the diabetic group with normal fundus or with background retinopathy. The findings imply that ERG examination with the described techniques does not reveal retinal dysfunction in diabetics before retinopathy can be detected by means of retinal biomicroscopy.

Pattern-reversal electroretinograms in squint amblyopia, artificial anisometropia and simulated eccentric fixation.

Pattern‐reversal electroretinograms were recorded in 10 normals and 10 adult patients with squint amblyopia (visual acuity 0.3 or less). The effects of artificial anisometropia and simulated eccentric fixation were tested in normals. The pattern‐reversal ERG amplitude was reduced linearly with increased defo‐cusing (0 to + 3 D). A significant amplitude reduction was observed when defocusing amounted to + 1 D. The amplitudes were not reduced below the range of normal variability at 4° of simulated eccentric fixation. In the amblyopic patients, refractive errors were corrected. None had eccentric fixation of more than 4°. Yet, the pattern‐reversal ERGs were lower in all amblyopic eyes compared with the opposite normal eyes. The difference in amplitude means was statistically significant. The finding supports the view that retinal function is impaired in human squint amblyopia.

Concordance of high-pass resolution perimetry and frequency-doubling technology perimetry results in glaucoma : no support for selective ganglion cell damage.

PurposeTo compare the results of frequency-doubling technology perimetry (FDT), assumed to test the magnocellular visual pathway, and high-pass resolution perimetry (HRP), assumed to test the parvocellular visual pathway, in patients with ocular hypertension or glaucoma. Patients and MethodsForty-eight consecutive patients with glaucoma or ocular hypertension, covering the entire range of optic nerve function from normal to severely damaged, were examined on the same day using FDT and HRP. ResultsThere was a linear correlation between both global and local indices in FDT and HRP (r = −0.84 P <0.0001 and r = 0.8 P <0.001, respectively). The HRP and FDT classifications agreed in 32 of the 48 (67%) eyes (Cohen &kgr; = 0.5). There was no significant difference between the ability of the different techniques to detect abnormality. ConclusionThe observations in the present study indicate either that both cell populations are similarly affected by glaucomatous damage or that both methods measure activity in the same cell populations.

Measurement of optic disc parameters on digital fundus photographs: algorithm development and evaluation

Purpose:  To develop and evaluate a simple and rapid algorithm for optic disc measurements on digital fundus photographs, relying on the macula–disc centre distance as a reference when converting length expressed in pixels to metric distance.

Perception of very small visual stimuli in the fovea: normative data for the Rarebit Foveal Test

Background:  Conventional visual tests are not sensitive enough to detect low degree neural damage, as 6/6 (1.0) visual acuity can be upheld with less than two‐thirds of the normal number of optic nerve axons. The aim of the current study was to evaluate the physiologic properties of a new computerised test, the Rarebit Fovea Test (RFT), using very small stimuli, by quantifying the effect of age and binocular summation in relation to stimulus luminance.