Biomedical subjects

I K Petropoulos

Publications and source records attributed to I K Petropoulos.

9 recordsLinked to original sources

PubMed2006

[Recurrence after primary vitrectomy for pseudophakic retinal detachment].

INTRODUCTION: The aim of this study was to evaluate the incidence of pseudophakic retinal detachment (RD) recurrence after primary vitrectomy. PATIENTS AND METHODS: This was a prospective nonrandomized consecutive case series study, evaluating two series presenting to our clinic with pseudophakic RD from 1998 to 2004 (103 eyes of 97 patients). The study included 24 consecutive pseudophakic eyes treated with gas vitrectomy surgery with placement of an encircling band from January 1998 to December 2000 (group A) and 79 consecutive pseudophakic eyes treated with gas vitrectomy surgery with no encircling band from January 2001 to December 2004 (group B). Pre- and postoperative characteristics were analyzed in both groups. In the cases of postoperative RD recurrence, we particularly analyzed the pre- and postoperative risk factors, as well as the anatomic and functional outcome. RESULTS: Visual acuity improved in 74/103 (71.8%) eyes from both groups postoperatively. Recurrence of RD after primary vitrectomy occurred in eight of 103 (7.8%) eyes in both groups. More specifically, two of 24 (8.3%) eyes in group A and six of 79 (7.6%) eyes in group B presented a recurrence after gas vitrectomy with encircling band and gas vitrectomy alone, respectively. Among these eight eyes, four eyes (50%) presented proliferative vitreoretinopathy (PVR) at the time of initial vitrectomy, while all eyes presented PVR at the time of recurrence (one grade B, seven grade C). These eyes required two additional interventions on average. Five eyes (62.5%) required silicone-oil tamponade for a good anatomic reapplication. DISCUSSION: These results show that recurrence after primary vitrectomy for pseudophakic RD is most often related to the presence of PVR before or after the first intervention. This series reports a success rate of 91.7% and 92.4%, respectively, for group A and B, thus demonstrating the efficacy of vitrectomy in the treatment of pseudophakic RD. This study also shows a nonsignificant difference in the recurrence rate among patients treated by gas vitrectomy and those undergoing gas vitrectomy in association with encircling band placement, which raises the question of the usefulness of an additional encircling band in pseudophakic RD.

Humans↗

PubMed2006

[Pseudophakic inferior retinal detachment or detachment with inferior breaks: clinical outcome and recurrences after primary vitrectomy-gas].

BACKGROUND: This study aims to evaluate the outcome of primary vitrectomy/gas for pseudophakic retinal detachment (RD) located inferiorly or associated to inferior breaks. PATIENTS AND METHODS: We performed a retrospective, non-randomised study comprising 18 pseudophakic RD eyes with inferior RD (group A) and 19 pseudophakic RD eyes with inferior breaks (group B) treated with primary vitrectomy and gas tamponade (SF (6) 20 %). Pre- and postoperative characteristics were analysed, focusing on RD recurrences. RESULTS: In group A, RD recurred in 2/18 eyes (11 %) and was associated to proliferative vitreoretinopathy (PVR) both at first intervention and on recurrence. In group B, RD recurred in 4/19 eyes (21 %). One eye presented PVR at first intervention and all at re-intervention. Anatomic reapplication was achieved after second vitrectomy/gas in 2/4 eyes of group B, whereas long-term silicon oil tamponade was needed in 2 eyes of each group. CONCLUSIONS: This series shows a high success rate of primary vitrectomy/gas in pseudophakic RD patients with inferior RD or detachment associated to inferior breaks. Recurrences after vitrectomy are most often related to the presence of PVR.

Aged↗

PubMed2005

[Proliferative diabetic retinopathy: vitreo-retinal complications are often related to insufficient retinal photocoagulation].

INTRODUCTION: Panretinal photocoagulation proved to be effective in preventing complications related to vasoproliferative diabetic retinopathy. Surgery is most often a last resort in cases of recurrent or persistent vitreous hemorrhage or retinal detachment. The aim of our study is to point out that eyes requiring surgery for complications related to vasoproliferative diabetic retinopathy are often insufficiently photocoagulated. PATIENTS AND METHODS: Retrospective analysis of operating protocols and surgical results for a series of 39 eyes of 36 patients with complications of vasoproliferative diabetic retinopathy. RESULTS: The mean age at the intervention was 57 years. Eighty-five percent of the eyes had a vitreous hemorrhage, 17% a retinal detachment. Eighty-five percent of the eyes had undergone a partial retinal photocoagulation before surgery. All eyes underwent a vitrectomy with segmentation of fibrovascular membranes. In 85% of the eyes studied, endolaser photocoagulation was necessary, sometimes even in the mid-periphery. After 39+/-26 months of postoperative follow-up, 97% of eyes showed improvement of the anatomical state of the retina and improvement or stabilization of visual acuity. CONCLUSION: Our results confirm the benefit of vitreoretinal surgery in complications related to vasoproliferative diabetic retinopathy. Moreover, it should be emphasized that complications requiring surgery often result from incomplete preoperative photocoagulation. To be effective, photocoagulation has to destroy more than 35% and up to 50% of photoreceptors. An intraoperative laser extension can reduce the risk of regrowth of fibrovascular membranes.

Diabetic Retinopathy↗

PubMed2004

Effect of acetazolamide on the optic disc oxygenation in miniature pigs.

BACKGROUND: The purpose of our study was to evaluate the variations of the optic disc PO (2) during normoxia and hyperoxia (100 % O (2)), before and after intravenous administration of acetazolamide. MATERIAL AND METHODS: PO (2) measurements were obtained at intervascular areas of the optic disc in 11 anaesthetized miniature pigs using oxygen-sensitive microelectrodes introduced through the vitreous cavity by a micromanipulator. PO (2) was measured continuously during 10 minutes under systemic normoxia and systemic hyperoxia. Oxygen measurements were repeated under these conditions after intravenous injection of acetazolamide (bolus of 500 mg) in 8 animals. RESULTS: In systemic hyperoxia, the optic disc PO (2) increased moderately (DeltaPO (2) = 4.7 +/- 2.5 mmHg; p < 0.001; n = 11) in parallel with systemic PaO (2). Acetazolamide led to a slow and progressive increase in the optic disc PO (2) (DeltaPO (2) = 2.1 +/- 1.7 mmHg; p > 0.1; n = 8 after 10 min, while DeltaPO (2) = 4.3 +/- 3.2 mmHg; p < 0.05; n = 8 after 30 min), in parallel with a slow and progressive increase in systemic PaCO (2). The optic disc PO (2) increased much more significantly after injection of acetazolamide under systemic hyperoxia (DeltaPO (2) = 13.3 +/- 3.1 mmHg; p < 0.001; n = 8). CONCLUSIONS: Systemic hyperoxia alone is not sufficient to increase substantially the optic disc PO (2) in miniature pigs due to a vasoconstrictor effect. Intravenous injection of acetazolamide can increase the optic disc PO (2) progressively, due to a vasodilatory effect of elevated systemic PaCO (2). The association of acetazolamide injection with systemic hyperoxia can further improve the oxygenation of the optic disc.

Acetazolamide↗

PubMed2004

Clinical outcomes and complications of intraocular lens exchange in patients with opacified hydrophilic acrylic lenses SC600-2.

BACKGROUND: The purpose of this study was to present the outcomes of intraocular lens exchange in patients with opacified hydrophilic acrylic intraocular lenses. PATIENTS AND METHODS: Fifteen patients, who underwent uncomplicated phacoemulsification and hydrophilic acrylic intraocular lens (model SC600-2) implantation with good visual recovery, were re-referred to our department 76 - 188 weeks post-surgery due to progressive visual loss resulting from opacification of the implant. Intraocular lens exchange followed. The method of lens exchange is described. The effect on the best corrected visual acuity and on their refraction, the operative and postoperative complications are reported. RESULTS: All 15 patients underwent intraocular lens exchange. Twelve patients (80 %) had improvement of their best corrected visual acuity, in two cases (13 %) the best corrected visual acuity did not change, and in one case (7 %) the best corrected visual acuity deteriorated, this being attributed to progression of her age-related macular degeneration. None of the patients developed zonular dehiscence; in one patient the exchange was complicated with posterior capsule rupture, and an anterior chamber intraocular lens was implanted. One patient required cutting of the haptics before removal of the opacified intraocular lens. The mean Snellen (decimal) visual acuity was 0.35 (range 0.1 to 0.6) before lens exchange and 0.49 (range 0.1 to 0.6) six weeks after; the difference was significant (P < 0.05). Excluding the patient with the deterioration of her age-related macular degeneration, mean visual acuity of the remaining fourteen patients after the intraocular lens exchange was even better (0.56). CONCLUSION: Exchange of opacified hydrophilic acrylic intraocular lenses seems to be the only currently available effective treatment, leading to improvement of visual acuity.

Acrylates↗

PubMed2004

Comparing phacoemulsification and extracapsular cataract extraction in eyes with pseudoexfoliation syndrome, small pupil, and phacodonesis.

BACKGROUND: This study aims to compare the frequency of intraoperative and postoperative complications between the modern phacoemulsification technique and the extracapsular cataract extraction technique in patients with pseudoexfoliation syndrome. PATIENTS AND METHODS: A prospective randomized study comprised 94 eyes with cataract, pseudoexfoliation syndrome, small pupil and slight to moderate phacodonesis. These eyes were randomly assigned into two groups. In the first group all patients (47 eyes) were operated on using a standard phacoemulsification technique (iris hooks, anterior capsule staining and capsular tension ring after capsulorhexis), while in the second group all patients (47 eyes) underwent a classic extracapsular cataract extraction. The main outcome measures were the frequency of intraoperative zonular tears, capsular rupture, vitreous loss and corneal edema, as well as the best-corrected visual acuity. RESULTS: Intraoperative zonular separation was recorded in one eye (2.1 %) and in 15 eyes (31.9 %) for the first and second groups, respectively (P < 0.001). Posterior capsule rupture with or without zonular separation occurred in two eyes (4.2 %) of the first group and in eight eyes (17.0 %) of the second group (P < 0.05). Vitreous loss also had a higher rate in the second group (17.0 % versus 4.2 %, P < 0.05). The postoperative difference in best-corrected visual acuity was also significant between the two groups, being higher in patients operated on using phacoemulsification technique (P < 0.001). CONCLUSIONS: In the difficult cases of cataract associated with pseudoexfoliation syndrome, small pupil and phacodonesis, the modern small-incision cataract surgery provides better results with a low rate of intraoperative and postoperative complications when compared with the extracapsular cataract extraction technique.

Aged↗

PubMed2003

[Idiopathic polypoidal choroidal vasculopathy associated with central retinal vein occlusion].

We present the case of a 54-year-old man with a previous history of central retinal vein occlusion in the right eye, who developed an idiopathic polypoidal choroidal vasculopathy in the right eye and an epiretinal membrane in the left eye. The patient's medical history disclosed arterial hypertension controlled with medical treatment. Although idiopathic polypoidal choroidal vasculopathy has been associated with several conditions, this is the first time that this entity has been described in the literature in association with central retinal vein occlusion.

Antihypertensive Agents↗

PubMedDate not supplied

Evaluating the management of diabetic retinopathy in a teaching center.

PURPOSE: To evaluate the efficacy of the management of diabetic retinopathy (DR) in the teaching center of the University Eye Clinic of Patras in Greece. METHODS: From 1989 to 1999, 302 patients with type I (5.3%) and type II (94.7%) diabetes mellitus (DM) were examined. Standard examination and treatment protocols were employed. Examinations and laser treatment were done by trainee specialists, under the supervision of the head physician (N.Ph), during their rotation in the retina and vitreous disorders outpatient department. RESULTS: At baseline examination, 17.9% of the eyes had no DR, 71.7% had nonproliferative DR, and 10.4% had proliferative DR. In 34.4%, no laser treatment followed. The other 65.6% underwent focal and/or grid laser and/or panretinal photocoagulation and/or vitrectomy. At the final examination, DR was still the same in 63.1% of the eyes, progression had occurred in 34.1%, and regression in 2.8%. Type I DM patients' eyes had a higher prevalence of proliferative DR at the final examination than type II DM eyes. There was also a significant correlation between progression of DR and duration of DM, insulin treatment for DM, and elevated glycosylated hemoglobin (HbA1c). CONCLUSIONS: Having applied standard examination and treatment protocols, the efficacy of the management of our diabetic patients was consistent with international standards, even though patients were treated mostly by doctors in training.

Adolescent↗

PubMedDate not supplied

Does identification of the causal organism of corneal ulcers influence the outcome?

PURPOSE: To investigate whether identification of the causal organism in corneal ulcers influences their outcome. METHODS: We retrospectively studied 114 patients, 72 males and 42 females aged 6-89 years, admitted to this eye clinic during the years 1994-2000 on account of an infectious corneal ulcer. Their examination included a detailed history, visual acuity measurement, and biomicroscopy in everyday follow-up. The ulcers were classified according to their severity and outcome. We assessed the cases where cultures had been done, reviewed the results, and searched for a possible correlation between the outcome and the fact of culturing the ulcer and identifying the causal organism. RESULTS: Of the 114 corneal ulcers studied, 23 were mild, 49 moderate, and 42 severe. Fifty (44%) had not been cultured, but 64 ulcers (56%) had been cultured, with a positive result in 37 cases (58%), Staphylococcus and Pseudomonas species being the most common organisms found. In moderate and severe ulcers, there was a tendency to a higher proportion of successful outcome for cultured ulcers, but with no significant correlation. CONCLUSIONS: Despite a tendency towards favorable results in culture-positive corneal ulcers, the influence of the detection of the organism on their outcome has not been proved. The role of the initial broad-spectrum antibiotic therapy remains important.

Adolescent↗