Use of fundus perimetry (microperimetry) to quantify macular sensitivity.

The advances in retinal imaging technologies have led to enormous innovation towards diagnostic in current ophthalmology, enabling the practitioner to detect early retinal changes and to document treatment effects. While, in the past, retinoscopy, visual acuity testing and perimetry played the major role in functional diagnostics, today, laser-based systems like laser scanning imaging systems especially for fluorescein-angiography, optical coherence tomography, electrodiagnostic systems and the analysis of retinal vessels may be used as well. However, the challenge to correlate subjective alterations or clinical changes with visual function, still remains. Micro- or fundus perimetry offers the option to test retinal sensitivity while directly observing the fundus. In this paper, we review the literature encompassing the results of more than 25 years of fundus perimetry, i.e. perimetry under simultaneous visualization of the fundus. During this time, results on known diseases and reproducibility of the technique were published, but a lot of work was also performed on the combination of different examination methods, allowing a synopsis of long-term results and new approaches by combining different methods and improving each of them. The first part of this review attends to improvements of the method. The second part addresses the clinical and diagnostic values. The final part is dedicated to diagnostic and long-term observation of fundus perimetric results beginning with common and rare diseases like age-related macular degeneration, macular holes and diabetic retinopathy, various types of macular dystrophies ending with challenges in conventional perimetry like glaucoma and malingering. Due to the experience and progress in the field of fundus perimetry and retinal imaging, the method has long passed its role of observing and has all the potential for prediction, early detection and treatment-monitoring of macular diseases.

Fundus perimetry with the Micro Perimeter 1 in normal individuals: comparison with conventional threshold perimetry.

PURPOSE: To determine differential light threshold values obtained with the Micro Perimeter 1 (MP1) in healthy volunteers and to correlate them with conventional automated static threshold perimetry using the Octopus 101 Perimeter. DESIGN: Prospective comparative observational study. PARTICIPANTS: Thirty healthy volunteers. METHODS: In 30 eyes of 30 healthy volunteers, static threshold perimetry was performed with the MP1 Micro Perimeter (Nidek Inc., Italy) and the Octopus 101 (Haag-Streit AG, Switzerland) in the same eye in random order. MAIN OUTCOME MEASURES: Differential light threshold values obtained with the MP1 and their difference to differential light threshold values with the Octopus. Differential light sensitivity was compared for 21 matching points in a rectangular test grid using similar examination settings with Goldmann III stimuli, stimulus presentation time of 100 msec, and white background illumination (1.27 cd/m2). RESULTS: For the 21 matching locations, mean differential light thresholds with the MP 1 and the Octopus were 15.5+/-0.8 decibels (dB) (range, 13.0-17.1) and 30.2+/-1.2 dB (range, 27.7-32.0), respectively. On the average, the Octopus showed higher threshold values for all test locations than the MP1. The mean difference between both examinations was 14.6+/-1.8 dB for all locations and 14.8+/-1.7 dB excluding the test locations at the blind spot. With a considerably high grade of variation according to the test point location, the difference between the 2 devices varied from 11.4 to 18.3 dB, showing a vertical asymmetry with a larger difference in the lower part of the visual field. Linear regression of the perimetric results for each test point location, excluding the area of the blind spot and the lower line of the test grid, showed significant correlation (r = 0.56; P = 0.036). CONCLUSIONS: The results show that the MP1 provides reproducible threshold values with a systematic difference compared with standard Octopus perimetry of approximately 15 dB. With a larger difference in the lower part of the visual field, differential light sensitivity values in microperimetry with the MP1 are comparable to the threshold values obtained with the Octopus 101 using a correction factor of 11.4 to 18.3 dB according to stimulus location.

Microperimetry--comparison between the micro perimeter 1 and scanning laser ophthalmoscope--fundus perimetry.

PURPOSE: To compare microperimetry using the scanning laser ophthalmoscope (SLO, Rodenstock, Germany) and the recently introduced Micro Perimeter 1 (Nidek Technologies, Italy). DESIGN: Prospective comparative observational study. METHODS: Fundus perimetry with static threshold perimetry was performed using the SLO and the MP1 in 68 eyes of 40 consecutive patients with different retinal diseases for example, central serous chorioretinopathy, macular dystrophy, and age-related macular degeneration. With both instruments, an automated 4-2-1 staircase strategy with Goldmann III stimuli and a comparable number of stimuli were applied. The depth and size of the detected scotomata as well as the location and stability of fixation were compared between both instruments. RESULTS: There was good concordance of results, with 75% (51 of 68 eyes) showing an equal defect. Whereas the MP1 showed larger defects (depth and size) in 23.5% (16/68) of eyes studied than the SLO, the defects appeared larger with the SLO in 1 eye. Concerning fixation analysis, similar results were found for fixation stability with stable fixation in 47.1% (MP1: 32/68) and 48.5% (SLO: 33/68) and likewise for the location of fixation with foveal fixation in 54.4% (37/68) with the MP1 and the SLO. Whereas the average number of stimuli was similar for both instruments (MP1 56.8 +/-16.1, SLO 62.9 +/- 17.0), examination time was prolonged with the MP1 (MP1: 11m 35s +/- 3m 47s, SLO: 10m 29s +/- 3m 23s). Throughout all examinations, fundus visualization with the SLO was superior to the MP1. CONCLUSIONS: For automated threshold microperimetry the MP1 provides results comparable to our SLO perimetry. Both instruments enable detection of sensitivity loss of the central visual field and an analysis of fixation behavior during microperimetry. Nevertheless, the MP1, with its automated real-time image alignment, facilitates examination. Additionally, the enlarged field allows testing in an area of 44 x 36 degrees instead of the 33 x 21 degree-area of the SLO. However, in comparison to our SLO-software, the current software of the MP1 requires improvements before exact measurements of defined retinal diseases are possible.

Periodontal disease as a risk factor for ischemic stroke.

BACKGROUND AND PURPOSE: Chronic infectious diseases may increase the risk of stroke. We investigated whether periodontal disease, including periodontitis and gingivitis, is a risk factor for cerebral ischemia. METHODS: We performed a case-control study with 303 patients examined within 7 days after acute ischemic stroke or transient ischemic attack, 300 population controls, and 168 hospital controls with nonvascular and noninflammatory neurological diseases. All subjects received a complete clinical and radiographic dental examination. The individual mean clinical attachment loss measured at 4 sites per tooth served as the main indicator for periodontitis. RESULTS: Patients had higher clinical attachment loss than population (P<0.001) and hospital (P=0.010) controls. After adjustment for age, sex, number of teeth, vascular risk factors and diseases, childhood and adult socioeconomic conditions, and lifestyle factors, the risk of cerebral ischemia increased with more severe periodontitis. Subjects with severe periodontitis (mean clinical attachment loss >6 mm) had a 4.3-times-higher (95% confidence interval, 1.85 to 10.2) risk of cerebral ischemia than subjects with mild or without periodontitis (

Fundus autofluorescence and fundus perimetry in the junctional zone of geographic atrophy in patients with age-related macular degeneration.

PURPOSE: To investigate retinal sensitivity in the junctional zone of geographic atrophy (GA), with variations in fundus autofluorescence (FAF) in patients with advanced age-related macular degeneration (AMD). METHODS: The spatial distribution and intensity of FAF were recorded with a confocal scanning laser ophthalmoscope (SLO). Eyes had normal background FAF (group 1) or increased FAF (group 2) surrounding the atrophic patches. Retinal sensitivity was assessed by applying light stimuli with static automated full-threshold fundus perimetry with a modified SLO. Threshold sensitivities were compared with age-matched normal sensitivities. RESULTS: Thirty-nine eyes of 39 patients with GA were included. Group 2 had a higher percentage of all test points outside the GA area, with decreased retinal sensitivity (44.9% +/- 28.7%) compared with group 1 (20.7% +/- 12.7%; P = 0.0063; multiple regression model; outcome variable is retinal sensitivity; covariates are group affiliation and GA area). Within group 2, the average percentage of stimuli in areas of normal FAF with reduced sensitivity was 38.0% +/- 33.0%, whereas the average percentage of stimuli in areas of elevated FAF with reduced sensitivity was 52.6% +/- 29.7% (P = 0.023, Wilcoxon signed rank test). CONCLUSIONS: Areas of increased FAF outside GA may be associated with variable degrees of loss of retinal sensitivity and suggest a functional correlate of excessive accumulation of retinal pigment epithelium lipofuscin in AMD. Combining in vivo recording of FAF and retinal sensitivity, using SLO technology, may give important clues in the understanding of mechanisms of disease.

Reproducibility of multifocal ERG using the scanning laser ophthalmoscope.

BACKGROUND: Prior to application of multifocal electroretinography (mfERG) using the scanning laser ophthalmoscope (SLO) in a clinical routine setting it is important to determine the reproducibility of this technique in normals during the use of monochromatic red HeNe laser light. METHODS: Thirty-five eyes of 35 volunteers (visual acuity > or =0.8) were examined using the SLO for mfERG with two test patterns in a 20-deg diameter field. Multifocal ERG was performed using the RETIscan system with a binary m-sequence technique. Evaluation was performed for the first-order kernel concentric ring segments. Three measurements were performed for each type of sequence (six sequences for seven hexagons, eight for 19 hexagons) with removal of electrodes between the recordings. Stimulus intensity for all subjects was set to 235 cd/m2 (background illumination 20 cd/m2). We used gold-foil electrodes to obtain good signal quality while not disturbing corneal transmission and refraction. RESULTS: The coefficient of variation for the P1 amplitudes for the center and surrounding ring(s) was 10.4% and 9.3% for seven hexagons and 15.2%, 9.3% and 7.6%, for 19 hexagons, respectively. The corresponding intraclass correlation coefficients varied between 0.59 and 0.77. The CV for the P1 peak times varied between 1.3% and 1.5% for ring analysis in seven and 19 hexagons. CONCLUSION: Our data shows that the setup of mfERG with the SLO provides a retest variability comparable with conventional CRT examinations. One advantage is the simultaneous visualization of the fundus with observation of fixation during examination, thereby allowing more confidence in pathological results.

The association of gingivitis and periodontitis with ischemic stroke.

OBJECTIVES: The aim of this study was to assess the associations of different periodontal parameters with cerebral ischemia. METHODS: In a case-control study, 303 consecutive patients with ischemic stroke or transient ischemic attack, and 300 representative population controls received a complete clinical and radiographic dental examination. Patients were examined on average 3 days after ischemia. The individual mean clinical attachment loss measured at four sites per tooth was used as indicator variable for periodontitis. RESULTS: Patients had higher clinical attachment loss than population (p<0.001). After adjustment for age, gender, number of teeth, vascular risk factors and diseases, childhood and adult socioeconomic conditions and lifestyle factors, a mean clinical attachment loss >6 mm had a 7.4 times (95% confidence interval 1.55-15.3) a gingival index >1.2 a 18.3 times (5.84-57.26) and a radiographic bone loss a 3.6 times (1.58-8.28) higher risk of cerebral ischemia than subjects without periodontitis or gingivitis, respectively. CONCLUSION: Periodontitis is an independent risk factor for cerebral ischemia and acute exacerbation of inflammatory processes in the periodontium might be a trigger for the event of cerebral ischemia.