Biomedical subjects

S Dimitrakos

Publications and source records attributed to S Dimitrakos.

5 recordsLinked to original sources

PubMed2006

Macular hole surgery without prone positioning.

PURPOSE: To investigate the role of vitrectomy without prone posturing in the anatomic and functional outcome of macular hole surgery (MHS). METHODS: Forty-one consecutive eyes of 41 patients with stage II-IV full-thickness macular holes underwent pars plana vitrectomy and 16% C3F8 tamponade. In 25 cases posturing group (P), subjects were instructed to assume prone positioning for 10 days postoperatively, whereas in 16 cases non-posturing group (NP) patients were advised to avoid lying supine but no other posturing instructions were given. Preoperative, intraoperative and postoperative clinical data were collected, with macular hole closure rate and change in LogMAR visual acuity, contrast sensitivity, metamorphopsia, and 25-Visual Function Questionnaire (VFQ-25) being the primary outcome measures. RESULTS: Over a mean follow-up of 4.21.2 months, anatomical hole closure was noted in 22/25 (88%) and 14/16 (87.5%) in groups P and NP respectively. Visual acuity improved by a mean of eight letters and there was no significant difference in the two groups (P=0.724). Similarly, postoperative prone posturing did not have an effect on the final contrast sensitivity, metamorphopsia, and VFQ-25 composite scores (P=0.238, P=0.472, and P=0.87, respectively). However, eyes in group NP developed significantly more severe cataract in the early postoperative period (P=0.02). CONCLUSIONS: Prone posturing following MHS provides no functional or anatomic benefit but it is associated with slower progression of cataract. Combined phacovitrectomy without face down positioning may be considered for all phakic patients undergoing MHS.

Aged↗

PubMed2006

Visual function following transpupillary thermotherapy with adjusted laser parameters for the treatment of exudative age-related macular degeneration: a pilot study.

PURPOSE: To evaluate the efficacy of transpupillary thermotherapy (TTT) using adjusted laser parameters for the treatment of choroidal neovascularization (CNV) secondary to age-related macular degeneration. METHODS: TTT was performed on patients with CNV using a diode laser (810 nm) for 60 s in a subthreshold manner. Power settings were varied between 460 and 1200 mW, depending on lesion size, presence of pigment epithelial detachment and the amount of fundal pigmentation and subretinal fluid. LogMAR visual acuity, contrast sensitivity (Pelli-Robson) and metamorphopsia (Amsler chart) were assessed prior to and 6 months following treatment. Subjects also self-administered the National Eye Institute 25-Item Visual Function Questionnaire. RESULTS: Thirty occult/minimally classic and eight predominantly classic membranes were treated with TTT. At 6 months, absence or significant reduction of fluorescein leakage was observed in 20 (53%) patients. Stabilization of vision (loss of less than 15 letters) was observed in 25/30 (83%) eyes with occult/minimally classic CNV and 5/8 (63%) eyes with predominantly classic CNV. Improvement of contrast sensitivity was noted in 15 (35%) eyes, in 10 (26%) eyes it remained unchanged and in 13 (34%) eyes it deteriorated. There was no statistically significant effect of TTT on the National Eye Institute 25-Item Visual Function Questionnaire composite or subscale scores. CONCLUSIONS: TTT using adjusted parameters depending on fundal characteristics appears to be effective in stabilizing subjective and objective visual ability in a considerable number of patients with subfoveal CNV due to age-related macular degeneration. Larger-scale studies are required to confirm the benefit of this technique as opposed to the natural history of occult CNV.

Aged↗

PubMed2004

Effect of laser photocoagulation treatment for diabetic macular oedema on patient's vision-related quality of life.

PURPOSE: To evaluate the effect of laser photocoagulation for diabetic macular oedema (DME) on patients' Vision Related Quality Of Life (VR-QOL) and to investigate associations between changes in self reported VR-QOL and changes in visual acuity following application of laser treatment. METHODS: Prospective cohort study of 55 subjects who underwent laser treatment for DME. Eligible patients with no history of previous laser photocoagulation self-administered the 51-item field-test version of the National Eye Institute Visual Function Questionnaire (NEI-VFQ) prior to treatment and 3 months following the last session of laser application. Visual acuity was measured by means of the Early Treatment of Diabetic Retinopathy (ETDRS) chart. Multi-item scales rating different aspects of VR-QOL were compared prior and after photocoagulation and the change in questionnaire's composite score following treatment was correlated to change in visual acuity and other determinants previously reported as risk factors in the diabetic population. RESULTS: Scale scores associated with general vision, near vision, distance vision, peripheral vision, vision-specific social functioning, vision-specific mental health, expectations for visual function and dependency due to vision were significantly improved following laser treatment. Multivariate models revealed that improvement of the NEI-VFQ composite score was significant in subjects younger than 65 years of age (p = 0.04) who received more laser burns (p = 0.02) and had worse vision-related QOL prior to laser treatment as expressed by the baseline NEI- VFQ composite score (p = 0.03). There was no statistically significant association between change in the composite score following laser treatment and stage of diabetic retinopathy, duration of diabetes or laser settings used during photocoagulation. CONCLUSIONS: Photocoagulation for DME has a beneficial effect on patients' subjective perception of visual function. The use of vision-targeted health status questionnaires in conjunction with the clinical examination appears to provide a more comprehensive overview of individuals' daily well- being following laser treatment.

Aged↗

PubMed1993

[Highly restricted detachment surgery without puncture: long-term results on the topic of postoperative "residual detachment" and late re-detachment].

BACKGROUND: Detachment surgery without drainage, a surgery limited to area of break, implies minimization of procedure and complications. In a 1st study (1970-1977) 1,000 consecutive detachments were treated with favorable results (primary reattachment in 83%, after reoperation in 91%, follow-up 4 months-7 1/2 years). A prospective 2nd study (8/1979-1/1980) followed to answer the questions: (1) Differential diagnosis between postoperative "residual detachments" and surgical failure. (2) Is rate of "late" redetachment after minimal segmental buckling greater than after cerclage? PATIENTS AND METHODS: Prospective study of 107 detachments operated 8/1979-1/1980 with follow-up of 11-11 1/2 years. Detachments: 21 eyes with aphakia, 1 with pseudophakia, 16 with PVR stage C1/C2. TREATMENT: cryopexy and segmental buckling or balloon in area of break without drainage, no vitrectomy, no cerclage. Orientation of buckles: 76 radials, 20 circumferentials, 11 radials with circumferentials. RESULTS: After 1 operation retina was reattached in 99 eyes (92.6%), after reoperation of primary failure (confined to original or to previously undetected break) the retina reattached in 104 eyes (97%). Types of postoperative "residual detachments" after non-drainage: (1) convex residual detachment (delayed absorption) or (2) concave residual detachment (traction), both of them with no hole (to observe) and (3) convex residual rhegmatogenous detachment (to reoperate). Longterm results (follow-up 11 years) of 104 reattached retinas: "early" redetachment (2-4 months postoperatively) in 6 eyes or 5.6% because of PVR and "late" redetachment (3 to 7 years postoperatively) in 7 eyes or 6.5% because of new breaks. After reoperation reattachment in 99 eyes (92.6%); only 1 of 107 eyes had 2 reoperations. Reasons for final failure: PVR (3.7%), no hole found (2.8%), massive choroidals (0.9%). CONCLUSION: After detachment surgery without drainage there can be: (1) convex or (2) concave "residual" detachment and (3) rhegmatogenous residual detachment with new contour (reoperation needed). Favorable longterm results after minimal surgery (6.5% "late" redetachment during 11 years postoperatively) and use of minimal surgery as reoperation (50% a balloon) for reattaching the retina do not support the necessity of a prophylactic cerclage as primary operation, even not as reoperation per se. A simple alternative to a surgical prophylaxis represents a so-called "passive" prophylaxis consisting in explaining the visual field to the patient and asking him to test it regularly.

Adolescent↗

PubMed1985

[Photocoagulation-induced macular scotoma and automated perimetry (Octopus)].

The size of macular scotomata is determined numerically by a series of parallel F2 programs of the Octopus Perimeter. As long as useful foveolar fixation is maintained, the results are reproducible within the limits due to fluctuation of the retinal sensitivity. The scotomata can be mapped on a fundus photograph either by direct calculation or after perimetric determination of a reference distance, e.g., foveola-disc or between angioscotomata. This method furnishes useful information which can facilitate evaluation of different types of lasers in macular photocoagulation.

Adult↗