An outbreak of acute postoperative endophthalmitis after cataract surgery.

BACKGROUND: Endophthalmitis is one of the most serious complications of ophthalmic surgery, which includes postoperative cataract extraction. Outbreak of acute postoperative endophthalmitis after cataract surgery has been reported in Thailand and other countries. OBJECTIVE: To describe an outbreak of acute postoperative endophthalmitis after cataract surgery that was referred to Chiang Mai University Hospital during March 2006. MATERIAL AND METHOD: Observational case series were made from the records of inpatients and outpatients, who had been referred for treatment of acute postoperative endophthalmitis after cataract surgery at a district hospital in northern Thailand. The surgery was conducted on two consecutive days by volunteer ophthalmologists of a non-profit foundation from Bangkok. RESULTS: In this outbreak, the authors recorded 31 endophthalmitis cases, with 33 eyes (bilateral 2 cases). Of the 33 endophthalmitis eyes, 32 occurred following extracapsular cataract extraction with intraocular lens and one after the secondary intraocular lens implant. Microbiological investigations in the hospital were done with aqueous tapping, vitreous tapping, and vitreous from pars plana vitrectomy. Gram-positive cocci were detected from vitreous tapping in four eyes. Thirty-two cases were managed with intravitreous antibiotics, one with subconjunctival antibiotic only, and all eyes were treated with fortified topical antibiotics. Fifteen eyes underwent pars plana vitrectomy Assessment of visual acuity (VA) before and after treatment showed improvement in 75.8% (25/33), decrease of VA in 9.1% (3/33), while visual acuity remained stable in 15.2% (5/33). CONCLUSION: In high-volume cataract surgery, an outbreak of endophthalmitis is always possible. Prompt and appropriate treatment can improve the visual outcome.

Endogenous endophthalmitis due to Salmonella choleraesuis in an HIV-positive patient.

PURPOSE: To report a case of endogenous endophthalmitis caused by the gram-negative bacterium Salmonella choleraesuis as a first sign of HIV infection in a patient from Thailand. METHOD: Case description and literature review. RESULTS: A 54-year-old male without systemic complaints developed non-painful panuveitis in his left eye accompanied by high intraocular pressure. On investigation, HIV serology was found positive, and aqueous and blood cultures revealed the bacterium Salmonella choleraesuis. Despite aggressive treatment with antibiotics, the affected eye did not improve, and his visual acuity decreased to no light perception. CONCLUSIONS: Endogenous endophthalmitis with the non-typhoidal Salmonellae can occur in the absence of systemic symptoms in an immunocompromised host.

Conjunctival autograft transplantation for primary pterygium.

PURPOSE: To evaluate the success rate of conjunctival autograft transplantation for primary pterygium. MATERIAL AND METHOD: The results of 56 patients with primary pterygia who underwent conjunctival autograft transplantation were retrospectively reviewed. The success rate was evaluated in terms of recurrence percentage of pterygia onto the cornea. RESULTS: Of the 56 patients, 20 were men and 36 women. The mean follow-up was 16.3 +/- 8.2 months. Three (5%) eyes had recurrent pterygium within 1 year. No serious sight-threatening complications were associated with this study. CONCLUSION: Conjunctival autograft transplantation can achieve very low recurrence rates for primary pterygium and may be considered a safe procedure.

Vision screening in schoolchildren: two years results.

OBJECTIVE: To assess the prevalence of visual impairment and ocular abnormalities among schoolchildren in Chiang Mai. DESIGN: A community-based survey. SUBJECTS AND METHOD: The vision screening project was conducted from June 2000 to March 2002. Students in grade I in the Chiang Mai municipal area were examined for visual acuity (VA), color vision, ocular alignment, anterior segment and fundus. Subjective refraction was done in students with subnormal vision (VA 20/30 or less). Referral to the hospital for further evaluation and treatment was made for students with strabismus, amblyopia and other ocular abnormalities. RESULTS: A total of 3,431 and 3,467 students were enrolled in 2000 and 2001, respectively. The prevalence of normal vision (VA 20/20), VA 20/30 or better in at least one eye and 20/40 or less in at least one eye were similar in both years (87%, 5.7%, 7.3% and 85%, 6.4%, 8.7%, respectively). There was no statistically significant difference in visual acuity among boys and girls in either year (p = 0.6 and p = 0.2). Prevalence of abnormal color vision was 4.2%. Other causes of visual impairment in both years included strabismus (1.5% and 6.2%), amblyopia (1.1% and 1.4%) and some congenital abnormalities. Most cases of amblyopia were due to uncorrected refractive errors. CONCLUSION: The authors found that over 10% of school-aged children had subnormal vision. The important causes of visual deterioration came from refractive errors, strabismus and amblyopia. The authors concluded that vision screening is a cost-effective way of reducing visual morbidity from preventable visual impairment, which is a tragedy that cannot be ignored.

Normative database of retinal nerve fiber layer and macular retinal thickness in a Thai population.

PURPOSE: To investigate the distribution of retinal nerve fiber layer (RNFL) and macular retinal thickness measured by optical coherence tomography (OCT) in a Thai population. METHODS: We studied one eye each of 250 healthy subjects [age > or = 18 years; spherical refractive error within +/-6 diopters (D); astigmatism < or =3 D; no ocular pathology]. A complete eye examination, standard automated perimetry, and fast RNFL and macular thickness measurement by OCT were performed, and a disc photograph was taken. The distributions of both thicknesses, including their relationship with demographic data, were analyzed. RESULTS: The mean +/- SD age of the study population was 44.7 +/- 12.2 years. The mean +/- SD RNFL thickness was 109.3 +/- 10.5 m, which was 10% thicker than that in the OCT normative database. RNFL decreased 2.3 m per decade (P < 0.001). Sex and spherical equivalent were not associated with RNFL thinning. The mean +/- SD central foveal thickness was 183.2 +/- 1.3 m. The macular thickness in the outer area was significantly thinner than that in the inner area (P < 0.001). The temporal regions were the thinnest among the four quadrants (P < 0.001). Thinning of all macular areas, except the center, was found to be associated with advancing age (P < 0.05). CONCLUSIONS: RNFL thickness in the measured Thai population was about 10% thicker than that in the original normative database. Macular thickness and RNFL thickness in the superior and inferior quadrants decreased with advancing age.

Blindness and low vision in a tertiary ophthalmologic center in Thailand: the importance of cytomegalovirus retinitis.

PURPOSE: To determine the causes of blindness and low vision in patients consulting a tertiary ophthalmologic center in northern Thailand. METHODS: The study population included 2,951 new consecutive patients from the Department of Ophthalmology at University Hospital in Chiang-Mai, Thailand. Main outcome measures were blindness and low vision, which were defined according to World Health Organization criteria. RESULTS: Of 2,951 patients, 369 (12.5%) had blindness and/or low vision (bilateral blindness in 73, unilateral blindness in 129, bilateral low vision in 77, and unilateral low vision in 90). Of the etiological causes of visual loss, age-related ocular disease was the most frequent (128 patients [35%]) followed by infections (66 patients [18%]) and trauma (43 patients [12%]). Although infections and trauma were the predominant causes of blindness, age-related disorders were frequently found in patients with low vision. Of anatomical sites, the lens (134 patients [36%]) was the main location of visual loss, closely followed by disorders of the retina and/or uvea (126 patients [34%]). Blindness and low vision were considered avoidable in 70% of cases. Of 73 patients with bilateral blindness, 14 had active cytomegalovirus retinitis, accounting for 19% of all patients with bilateral blindness. CONCLUSION: The most common causes of blindness and low vision in a tertiary center in northern Thailand were age-related ocular disorders and infections, which were predominantly cases of cytomegalovirus retinitis in human immunodeficiency virus-infected patients.