PubMed Health⌕ Search

Biomedical subjects

S Dinakaran

Publications and source records attributed to S Dinakaran.

At least 19 recordsLinked to original sources
PubMed2006

Retinal pigment epithelial changes and choroidal neovascularisation at the edge of posterior staphylomas; a case series and review of the literature.

PURPOSE: To report five myopic patients who presented with a variety of changes at the edge of posterior staphyloma. METHODS: Retrospective, observational case series. The clinical and angiographic records of five patients who showed changes at the edge of posterior staphyloma were reviewed. One of these patients had been referred querying macular dystrophy. RESULTS: On fundus examination, three patients showed retinal pigment epithelial (RPE) changes at the edge of the staphyloma and two showed RPE atrophy with surrounding haemorrhages. Fluorescein angiography revealed areas of hyperfluorescence at the point of change of curvature of the staphyloma suggestive of RPE atrophy in all patients. In two patients, a choroidal neovascular membrane was seen. Indocyanine green angiogram carried out in one patient showed the presence of an occult choroidal neovascular membrane with preservation of the adjacent choriocapillaris. CONCLUSION: This case series illustrates the variety of changes that can occur at the edge of posterior staphylomas, which ranged from RPE disturbance to choroidal neovascular membrane formation. In one of the patients, these changes were mistaken for macular dystrophy. Our observations also support the hypothesis that chorioretinal changes occur at the edge of staphylomas and may predispose to choroidal neovasularisation.

Adolescent↗
PubMed2005

Oral fluorescein angiography with the scanning laser ophthalmoscope in diabetic retinopathy: a case controlled comparison with intravenous fluorescein angiography.

AIM: To compare the performance of oral fundus fluorescein angiography with a confocal scanning laser ophthalmoscope (SLO) with intravenous fundus fluorescein angiography (IVFFA) with a fundus camera in the assessment of sight-threatening diabetic retinopathy. PATIENTS AND METHODS: A total of 25 patients undergoing IVFFA to investigate their diabetic retinopathy were recruited. Participants returned 1 week later and an oral angiogram with the SLO was performed. Six facets of the oral and intravenous angiograms were scored and compared: visualization of the foveal avascular zone (FAZ); branch retinal identification; macular leakage; identification of microaneurysms in areas of macular leakage; peripheral nonperfusion, and leakage from neovascular complexes. RESULTS: Compared to IVFFA, the FAZ was unreliably visualized with oral angiography (Kappa 0.1, 95% CI 0-0.3). In contrast, macular leakage (Kappa 0.78, 95%, CI 0.72-0.83), identification of microaneurysms in areas of macular leakage (Kappa 0.78, 95%, CI 0.72-0.83), and neovascular complexes (Kappa 1.0) were reliably seen. Analysis of the visualization of peripheral nonperfusion was complicated by the finding that profuse dye leakage from neovascular complexes obscured the view of the peripheral retina. If the five angiograms in which this occurred were excluded, oral angiography identified 23 of the 24 eyes in which significant nonperfusion was found on IVFFA. CONCLUSION: Oral angiography with the SLO can provide high-quality angiograms that allow judgments to be made about the presence of treatable diabetic maculopathy, proliferative diabetic retinopathy, and peripheral nonperfusion. In the presence of coexisting macular oedema, it proved to be an unreliable technique with which to investigate foveal ischaemia.

Administration, Oral↗
PubMed2004

Unintentional inversion of corneal buttons during penetrating keratoplasty: clinico-pathological report of two cases.

AIM: This report describes the clinico-pathological features of unintentionally inverted corneal buttons in two patients. METHODS: A clinico-pathological report. RESULTS: Two patients who underwent repeat keratoplasty for failed grafts were found to have inverted corneal buttons on histopathological examination. A detailed description of the pathological features of the inverse keratoplasty and the clinical outcome after repeat keratoplasty is presented. CONCLUSION: Inadvertent inverse keratoplasty should be considered as a rare cause of corneal graft failure. The serious complication of anterior chamber epithelialization seems to be unlikely and the prognosis following repeat penetrating keratoplasty appears to be very good.

Adult↗
PubMed2002

Debris on processed ophthalmic instruments: a cause for concern.

PURPOSE: To assess the quality of processed ophthalmic instruments and look for the presence of foreign material on the surface of these instruments. METHODS: Data were prospectively collected on the presence of debris on processed instruments in the trays used for phacoemulsification surgery. All instruments were examined under an operating microscope before use and details of the types of debris on the various instruments were noted. If debris was found, a new tray was opened to obtain a clean instrument. RESULTS: Forty-seven trays were opened for use during the study period. Deposits on instruments were found in 29 (62%) trays. These were mainly present on the intraocular lens introducers. Loose fibres were found on instruments from eight (17%) trays. Debris was found in the aspiration channels of three (6%) hand pieces. CONCLUSIONS: A significant number of processed ophthalmic instruments had debris on their surfaces. To reduce the risk of intraocular inflammation and of transmission of prion diseases the instruments should go through a thorough decontamination process before sterilization. Routine mechanical cleaning at the end of surgery and ultrasonic cleaning before sterilization should reduce the occurrence of debris on the instruments. Instruments should also be inspected under the operating microscope before use.

Corneal Edema↗
PubMed2001

Topical anesthesia for phacoemulsification and painless subconjunctival antibiotic injection.

Endophthalmitis is a serious postoperative complication of phacoemulsification surgery. Administration of a subconjunctival antibiotic is a common method of prophylaxis in the United Kingdom and other countries. Injection of subconjunctival cefuroxime can be very painful, especially after phacoemulsification under topical anesthesia. Our experience is that this could be the only painful step in the entire operation. We evaluated a technique in which buffered lignocaine is injected into the subconjunctival space before the antibiotic injection. The technique was used in 46 eyes (46 patients) that had phacoemulsification under topical anesthesia. Eighty-seven percent of patients found the injection painless, 6.5% reported that the pain was very negligible, and 6.5% reported a moderate degree of pain.

Aged↗
PubMed2001

Transvitreal fine needle aspiration biopsy: the influence of intraocular lesion size on diagnostic biopsy result.

PURPOSE: To determine the efficacy of transvitreal biopsy in the diagnosis of suspected intraocular malignancy and simulating conditions. METHODS: We performed a retrospective study of the case notes from patients who underwent pars plana transvitreal biopsy from July 1986 to October 1999. We studied the relationship between lesion thickness as measured by A-scan ocular ultrasound and the incidence of a successful diagnostic biopsy. We assessed the diagnostic accuracy by comparing the biopsy result with the histological examination of any subsequently enucleation specimens and noted the incidence and severity of complications attributable to the biopsy. RESULTS: A total of 83 biopsies were performed for choroidal masses. There was insufficient material for cytological examination in 10 cases, and sufficient material in 73 cases (an overall diagnostic report rate was 88%). There was a strong correlation (p = 0.0004, Mann-Whitney U-test) between a diagnostic biopsy result and the thickness of the lesion on A-scan ultrasound: a biopsy was diagnostic in only 40% (4 of 10) of choroidal lesions less than 1.99 mm thick, whereas biopsies taken from lesions between 2.00 and 4.00 mm thick were diagnostic in 90% of cases (27 of 30). In thicker lesions of 4 mm or more the cell aspirate was sufficient to make a diagnosis in 98% (42 of 43). Following diagnostic biopsy 27 patients had their tumours resected, and the histology results following enucleation confirmed the cytological diagnosis of malignancy in 96% of these cases (26 of 27). CONCLUSION: Transvitreal biopsy is a highly accurate diagnostic procedure with a low complication rate. It is a reliable diagnostic tool in suspicious choroidal lesions greater than 2 mm thick.

Biopsy, Needle↗
PubMed2000

Is the first post-operative day review necessary following uncomplicated phacoemulsification surgery?

PURPOSE: To assess the necessity for first post-operative day review in determining the need for post-operative intervention in patients who had uncomplicated phacoemulsification surgery. METHODS: A retrospective study was carried out to review the first post-operative day findings in patients who underwent uncomplicated phacoemulsification surgery by a single surgeon between January 1997 and March 1998. The findings analysed were wound integrity, corneal clarity, anterior chamber activity, intraocular pressure and the intraocular lens status. The need for medical or surgical intervention was also analysed. Those eyes that had coexisting ocular pathology such as glaucoma, ocular hypertension, uveitis, trauma or previous intraocular surgery were excluded from the study. Fisher's exact test was used to compare the difference between the groups. RESULTS: Seventy-one eyes of 71 patients who underwent an uncomplicated phacoemulsification procedure were included in the study. Intraocular pressure of 30 mmHg or greater was found in 7 eyes (10%), all of which also had corneal oedema. These patients received acetazolamide SR 250 mg twice daily for 3 days. Another 21 eyes (30%) had corneal oedema for which no specific treatment was given. The intraocular pressure had returned to baseline and corneal oedema resolved by the first clinic follow-up in 1-2 weeks. None of the 71 patients needed surgical intervention in the post-operative period. CONCLUSION: First post-operative day review is necessary as it gives an opportunity to manage the post-operative rise in intraocular pressure.

Adult↗