COMPARISON OF FAST PERIMETRIC STRATEGIES USING G2 PROGRAM ON OCTOPUS 101 PERIMETER

Background. The duration of the perimetric examination was significantly shortened by development of fast perimetric strategies. By analyzing the results of normal, dynamic and TOP strategy we studied the differences in determination of MD, LV, in determination of number of all points with a deficit and number of points with a significant deficit of p &lt; 0.5%.Methods. 22 normal visual fields of 17 subjects (mean age 33 ± 15 years) and 22 visual fields with defects of 17 patients (47 ± 16 years) having different types and degrees of visual lesions were examined. All visual fields were examined once with each strategy in alternating order using Octopus 101 perimeter with the G2 program.Results. No statistically significant differences were measured in MD values. In abnormal visual fields group, TOP strategy showed 11 ± 14 dB2 lower LV values compared to dynamic strategy (p &lt; 0.01) and 9.8 ± 16 dB2 lower LV values compared to normal strategy (p = 0.02). In the abnormal visual fields group the dynamic strategy measured in average 3 points with the deficit less compared to the other two strategies (p &lt; 0.05). There were no significant differences between strategies in the number of points with a deficit of p &lt; 0.5%.Conclusions. With the exception of lower LV values measured with TOP strategy, the differences between TOP, dynamic strategy results are small and the time sparing benefits are substantial. Therefore the usage of fast perimetric strategies is clinically justified.</p

COMPARISON OF FAST STRATEGIES WITH NORMAL THRESHOLD STRATEGY USING OCTOPUS PROGRAMME M2 IN CENTRAL FIELD DEFECTS

Background. Fast test strategies are relatively new methods for assessing differential light sensitivity threshold in computer assisted perimetry. The purpose of our study was to compare and evaluate the accuracy of normal threshold strategy, dynamic strategy and TOP (Tendency Oriented Perimetry) strategy by testing central visual field with programme Octopus M2, which has the greatest concentration of test points (81 test points in the central 10 degrees area). A similar comparative study with programme Octopus M2 has not been done yet.Methods. 30 normal eyes and 30 eyes with central field defects of different degrees and etiology were tested. The testing was performed with Octopus 101 perimeter in standard conditions. The programme M2 was used. Each eye was tested three times – once with normal, once with dynamic and once with TOP strategy. Each subject had at least 20 minutes of break between each testing. The sequence of the strategies was equally alternated for all three strategies.Differences between strategies were statistically evaluated regarding examination time, parameters MS (Mean Sensitivity), MD (Mean Defect) and LV (Loss Variance), the extent and depth of a field defect, sensitivity and specificity.Results. Fast strategies significantly reduce examination time. There were no statistically significant differences in any of the observed parameters in the group of eyes with field defects. There were statistically significant differences in MS and MD in the group of normal eyes (p &lt; 0.01), but these differences were not clinically important. All three strategies are well comparable regarding sensitivity and specificity.Conclusions. Fast test strategies (especially TOP strategy) represent a good alternative to normal threshold strategy. Better efficiency of fast strategies justifies their greater clinical application.</p

Spontaneous full thickness macular hole development and closure in a patient with nucleus dislocation due to hypermature cataract: a case report

Spontaneous posterior capsule rupture with lens-nucleus dislocation is a very rare entity, as is the development and spontaneous closure of a full thickness macular hole (FTMH) after vitrectomy. The occurrence of these two entities in one eye has not been previously described. A 79- year-old woman was referred because of the right eye intermittent pain and progressive visual loss. Best corrected visual acuity (BCVA) with correction for aphakia was 20/20. Intraocular pressure was normal with therapy. The cornea, anterior chamber, and vitreous were clear. Gonioscopy was normal. The capsular bag was clear, with rolled-up anterior and posterior lens capsule, and the nucleus dislocated in the vitreous. As surgery waiting time was prolonged due to administrative problems, the patient’s intraocular pressure (IOP) increased and cystoid macular edema (CME) with lamellar macular hole developed. The patient underwent pars plana vitrectomy with endophacofragmentation and epiretinal membrane peeling. Postoperative optical coherence tomography was normal, BCVA was 20/40, and IOP was normal with topical therapy. One month after surgery, the eye was without signs of inflammation and IOP started rising in spite of maximum therapy. CME reoccurred and progressed to a FTMH, which started closing spontaneously in one month. One year after surgery, IOP normalized and FTMH closed completely. A dislocated crystalline lens in a quiet eye with normal BCVA, which rapidly developed into intractable glaucoma and FTMH, is an unusual finding. The deterioration was followed by spontaneous IOP normalization and macular hole closure. Such unexpected disease course, suggesting a possible autoimmune reaction, has not yet been describe

Anatomical success rate of pars plana vitrectomy for treatment of complex rhegmatogenous retinal detachment

BACKGROUND: Pars plana vitrectomy (PPV) is preferred surgical procedure for the management of complex rhegmatogenous retinal detachment (RRD). The purpose of this study was to evaluate the anatomical results of primary PPV for the treatment of primary complex RRD and to determine the influence of lens status, tamponading agent, preoperative proliferative vitreoretinopathy (PVR) and axial length (AL) of the eye upon the anatomical outcome. METHODS: A retrospective consecutive chart analysis was performed on 117 eyes from 117 patients with complex RRD managed with PPV. Fifty-nine eyes were phakic and 58 pseudophakic eyes. All patients had a minimum follow-up period of 12 months. Eyes were classified into groups using independent variables (first classification based upon lens status and tamponade used, second classification based upon lens and PVR status and third classification based upon AL of the eye). The groups were compared for anatomical outcomes (dependent variables) using nonparametric- or, in case of normally distributed data, parametric- statistical tests. RESULTS: Retinal reattachment rate in phakic eyes was 94.9% compared to 93.1% in pseudophakic, with no statistically significant difference between the two. The overall retinal reattachment rate with single surgery was 94.0%. Final reattachment rate was 97.4%. In case of established PVR >/= C1, the reattachment rate was not statistically different (92.6%) from eyes with no PVR (91.1%) irrespective of lens status. A statistically significant difference was found between redetachment rates only between phakic eyes with gas tamponade compared to silicon oil (SO) (p = 0.001). Reattachment rate proved to be similar in both AL groups ( 24 mm). CONCLUSIONS: High anatomical success rate of primary vitrectomy for complex RRD with either gas or SO tamponade was achieved in phakic as well as pseudophakic eyes irrespective of AL of the eye

POLYMORPHISMS OF DOPAMINE RECEPTORS IN PATIENTS WITH RETINITIS PIGMENTOSA

Background. Dopamine (DA) has a specific role in modulation of retinal function, renewal and phagocytosis of shed discs by the retinal pigment epithelium. Animal model of RCS (Royal College of Surgeons) rats which have impaired retinal phagocytosis has shown an appearance similar to the clinical picture seen in patients with advanced retinitis pigmentosa (RP). Based on RCS rats’ studies and the fact that DA has an important role in retinal renewal we assume that certain DA receptor polymorphisms might play a role in pathogenesis of RP.Materials and methods. We compared a group of 65 RP patients and 80 healthy individuals. Using PCR method and restriction with DdeI, TaqI or MspI restriction enzymes (DRD1, DRD2, DRD3 respectively) we determined the polymorphisms of DRD1, DRD2 and DRD3. Three models of expression (codominant, dominant, recessive) were statistically compared with χ 2-test.Results. We found an evidence for association between DRD2 TaqI RFLP, OR = 1.9 (95% CI: 1.7–2.3), p = 0.08, under autosome recessive model of inheritance. Other models for any of the DRD polymorphisms did not show a significant association with RP.Conclusions. A potential association was found between RP and DRD2 polymorphism. Further investigation is needed to confirm potential implication of DRD2 in the pathogenesis of RP.</p

ELECTROOCULOGRAPHY AND PATTERN ERG IN THE DIAGNOSTICS OF BEST’S VITELLIFORM DISTROPHY

Background. The aim of the study was to develop electrooculography in accordance with ISCEV standards and to test its accuracy in the diagnosis of Best’s disease, where the EOG results should be invariably abnormal in all affected members. The pathophysiology of Best’s disease is not yet completely understood, so pattern and full field flash ERG responses compared to visual acuity and stage of the disease were used to asses the neurosensory retinal function in different stages of Best’s disease.Patients and methods. The EOG was recorded in accordance with ISCEV standards on 30 healthy individuals to determine normal values of our laboratory. Pattern as well as photopic and scotopic ERG were recorded on 24 eyes of 12 patients with typical Best’s disease with abnormal EOG responses. The results were compared to visual acuity and stage of the disease.Results. Our EOG normative data are comparable with results from other laboratories: the mean value of Arden ratio is 2.32, the range of 2 standard deviations from the mean value is from 1.6 to 3.04. The patients with Best’s disease have statisticaly significant lower values of Arden ratio (the mean value beeing 1.19). 12 patients (24 eyes) with Best’s disease with abnormal EOG values were divided in two groups according to visual acuity. In the first group of 12 eyes with visual acuity &gt; 0.5 PERG P50 and N95 responses were all in the normal range. In the second group of 12 eyes with visual acuity 0.5 or less PERG showed reduced both P50 and N95 responses in 5 eyes, and N95 solely, in two eyes.The photopic and scotopic electroretinographic responses were normal in all patients. Progression of the disease, seen in the deterioration of visual acuity, corresponded well with reduction of both PERG P50 and N95 responses. There was no correlation found between visual acuity and EOG responses.Conclusions. In the study on patients with Best’s disease, it was confirmed that EOG is a very sensitive test for detecting the disease. On the basis of EOG results alone no assumption can be made about the stage of the disease, as EOG is abnormal in all the patients, regardless of the stage of the disease. Pattern ERG is getting abnormal with progression of the disease, indicating relative preservation of neurosensory retina in initial stages of the disease, giving opportunity for electrophysiological determination of the progression of the disease.</p

PATTERN ELECTRORETINOGRAPHY IN RELATION TO KINETIC AND STATIC PERIMETRY AND VISUAL ACUITY IN RETINITIS PIGMENTOSA

Background. This study was conducted to assess whether pattern ERG is a sensitive test in evaluating the retinal function in patients with retinitis pigmentosa. We wanted to determine how pattern ERG, reflecting the activity of inner retinal layers, is related to other psychophysical tests such as perimetry and visual acuity.Methods. An analysis was performed on 50 eyes of 25 patients with typical rod-cone retinitis pigmentosa. The standard Snellen visual acuity was tested. Visual field sensitivity was measured with automated static perimetry (Octopus G2 program) where mean defect was taken as an index of visual field loss. In kinetic perimetry (Goldmann) the average radius of the visual field measured with target II/4 and V/4 was calculated. Transient pattern ERG and all five flash ERG responses were also measured according to ISCEV standards. Amplitudes of pattern ERG P50 and N95 waves were compared to results of visual acuity and visual field testing.Results. In our group of 25 RP patients with visual acuity ranging from 0.16 to 1.0, PERG responses were preserved much better than full field ERGs. 72% of them had still recordable PERG responses, while 48% had cone and only 32% maximal responses. Scotopic rod responses were extinguished in all eyes. The normalized amplitudes of the PERG responses were also much higher (43.5%) than cone (22.5%) or maximal responses (4.5%). A strong correlation of both P50 and N95 amplitudes with Octopus mean defect index was found. In kinetic perimetry the correlation with PERG amplitudes was also high, but it was better with II/4 than with V/4 target. Patients with high preserved ERG responses had good visual acuity. In all patients with visual acuity less than 0.4 both flash and pattern ERG responses were already absent.Conclusions. This study shows that pattern ERG is an objective and sensitive test in evaluating the functional visual loss in retinitis pigmentosa. Amplitudes of P50 and N95 responses are linearly related to the remaining functional retina. The agreement is more pronounced in static than kinetic perimetry. Visual acuity affects the pattern ERG more than flash ERG.</p