Min Hsiu Shih

Effect of artificial tears on corneal surface regularity, contrast sensitivity, and glare disability in dry eyes

OBJECTIVE To investigate the effects of artificial tears on corneal surface regularity and visual function in dry eyes. DESIGN Nonrandomized, comparative trial. PARTICIPANTS Forty patients (40 eyes) with dry eyes with (group 1, n = 15 eyes) or without (group 2, n = 25 eyes) punctate epithelial keratopathy and a normal control group of 20 individuals (20 eyes) with no ocular abnormalities (group 3). METHODS In both dry and normal eyes, the surface regularity index (SRI), surface asymmetry index (SAI), and potential visual acuity (PVA) were measured by computer-assisted videokeratography (TMS-1; Computed Anatomy, New York, NY). Spatial-contrast sensitivity and glare disability were also measured before and 1 minute after instillation of artificial tears. MAIN OUTCOME MEASURES Differences in SRI, SAI, PVA, spatial-contrast sensitivity, and glare disability between groups, before instillation of tears, and within groups, after instillation of tears. RESULTS Compared with group 3, eyes in group 1 had significantly worse SRI, SAI, PVA, and contrast sensitivity (incomplete glare disability data precluded analysis) before instillation of artificial tears. Differences in corneal surface regularity and visual function between groups 2 and 3 were not significant except for a significantly increased glare disability at low spatial frequency (1.5 cycles per degree [cpd]) in group 2. Significant improvement in SRI, SAI, PVA, and contrast sensitivity were observed after instillation of artificial tears in group 1. In groups 2 and 3, the only significant changes were improvement in glare disability at 1.5 cpd and worsening of the SRI, respectively. CONCLUSIONS Tear film changes in dry eye patients may lead to irregularities on the corneal surfaces, causing glare disability. However, these changes may be too subtle in the early stages of dry eyes to be detected by corneal topography or contrast sensitivity measurements. Significant improvement in SRI, SAI, PVA, and contrast sensitivity were found after instillation of artificial tears in dry eyes with punctate epithelial keratopathy.

Major Pediatric Ocular Trauma in Taiwan

PURPOSE To investigate major pediatric ocular trauma in Taiwan. METHODS Retrospective review of medical records of all patients 15 years and younger who were hospitalized with a primary diagnosis of eye injury at National Cheng Kung University Hospital, Taiwan, between June 1988 and May 2006. RESULTS There were 156 children (156 eyes) 1.1 to 15.0 years (mean+/-standard deviation, 7.1+/-0.3 years; boy: girl ratio: 2.1:1). Objects most often causing penetrating injury were scissors (13.5%), pencils/pens (12.2%), broken eyeglasses/spectacles (7.7%), and knives (6.4%). Most blunt trauma occurred in traffic accidents (5.8%). Most injuries occurred at home, followed by on the street, at school, and at sports venues. Injuries were classified as open globe (71.2%), adnexal only (18.6%), or closed globe (10.3%), and included corneal laceration (40.4%), lens damage (27.6%), hyphema (25.6%), and eyelid laceration (23.7%). Most surgical procedures were primary repair (88.5%) or removal of a damaged lens (22.4%). Additional surgery was performed in 19.9% of cases. After treatment, 56.4% of eyes had corneal opacity/scar and 7.1% became phthitic; 52.6% had good visual outcome, whereas 23.1% had poor final vision. Compared with visual acuity measured on admission, final visual acuity was improved in 76.1%, unchanged in 19.7%, and worse in 4.3%. Predictors of worse outcome were open-globe injury and larger wound size, posterior segment involvement, and presence of an intraocular foreign body. CONCLUSIONS Most of the children hospitalized for major ocular trauma are younger boys with penetrating injuries suffered at home. Most injuries could have been prevented by increased awareness and reduction of risk factors, and the authors urge better public education for improved safety.

Retinopathy of prematurity in southern Taiwan: A 10-year tertiary medical center study

BACKGROUND/PURPOSE Retinopathy of prematurity (ROP) is a leading cause of childhood blindness. This retrospective study investigated ROP, including incidence, demographic information,risk factors, treatments, and refractive outcomes, in southern Taiwan over a 10-year period. METHODS The authors retrieved the National Cheng Kung University Hospital database between the years 2000 and 2009 for newborns with a gestational age less than 32 weeks and/or with a birth weight less than 1500 g who had been screened for ROP. We recorded sex, birth weight, gestational age, in-hospital versus out-of-hospital birth, paternal and maternal ages, whether there were multiple gestations, parity, Apgar scores, length of hospital stay, risk factors, presence and severity of ROP and whether it was treated, and refraction at the last visit. Regression analyses were performed to identify risk factors for ROP. RESULTS A total of 503 live births were included. ROP was identified in 190 (37.8%) and met criteria for treatment in 59 (11.7%).ROP was diagnosed as stage 1, 2, 3, 4, and 5 in 61 (12.1%), 36 (7.2%), 81 (16.1%), 11 (2.2%), and 1 (0.2%) infant, respectively. Lower birth weight and younger gestational age were risk factors for greater severity of ROP (p < 0.001). Of the 167 with extremely low birth weight (<1000 g), 118 (70.7%) had ROP and 49 (29.3%) required treatment. On univariate analysis, low birth weight, younger gestational age, and risk factors such as respiratory distress syndrome, chronic lung disease, patent ductus arteriosus, surfactant usage, indomethacin usage, sepsis, upper gastrointestinal bleeding, blood transfusion, and necrotizing enterocolitis were associated with ROP. Multivariate logistic regression analysis showed that only lower birth weight was a significant and independent risk factor for ROP. Myopia (76%)and anisometropia (28%)were common in advanced ROP. CONCLUSION Low birth weight is a major risk factor for ROP. Infants with extremely low birth weight had a higher risk of severe ROP. Common ocular sequelae of advanced ROP were myopia and anisometropia.

A cluster of endophthalmitis caused by Mycobacterium abscessus after cataract surgery

We report two cases of postoperative endophthalmitis after cataract surgery caused by the same strain of Mycobacterium abscessus confirmed by arbitrarily primed polymerase chain reaction, sequencing of the erythromycin ribosome methyltransferase gene and pulsed-field gel electrophoresis. The outcomes were poor despite aggressive treatments. This is the first report of nontuberculous mycobacteria as a causative pathogen for a cluster of endophthalmitis.

Paederus-induced keratitis

Purpose: To report the clinical picture and management of 4 cases of presumed paederus-induced keratitis. Methods: The clinical characteristics of the anterior segment and periocular area were presented. The outcomes and healing course of the corneal lesions were recorded. Results: Each patient sustained an accidental eye injury from a beetle while riding a motorcycle. Three cases were complicated by periocular dermatitis. All patients had diffuse punctate epithelial erosions or large epithelial defects on the unilateral cornea. Prolonged corneal epithelialization was noted after lubrication with artificial tears and wearing a contact lens. Reepithelialization was promoted after topical supplementation with 20% autologous serum. All 4 patients had good visual outcomes. Two patients healed with a faint corneal scar. Conclusions: Paederus-induced keratitis could result in extensive involvement of the corneal surface. Keratitis with a large epithelial defect mimicking the corrosive lesion of a chemical burn requires aggressive therapy, such as autologous serum combined with a bandage contact lens. Avoiding contact with the crushed body of the beetle while rubbing the eye is mandatory to prevent this type of keratitis.

Astigmatism in children with epiblepharon

Purpose: To study the relationship between astigmatism and epiblepharon in Taiwanese children that need surgical correction. Methods: In a retrospective case-control study, a total of 254 eyes in 134 children surgically treated for lower-lid epiblepharon were studied. A further 205 eyes in 104 children 4-7 years of age were included as controls. Data on age, sex, severity of preoperative corneal erosion, best-corrected visual acuity, and preoperative and postoperative refractive errors were recorded. The data of astigmatism were decomposed into P90 (at 90 °) and its oblique meridian Pobl. Nonparametric tests were used to compare the severity of astigmatism. Results: No significant difference between age group (<4, 4-7, >7 years) in P90 was shown in children with epiblepharon. Pobl was trivial in each group of epiblepharon. Children with epiblepharon 4-7 years of age had significantly (P < 0.001) greater P90 than controls (1.12 vs. 0.47 D). P90 and Pobl were not significantly changed postoperatively. In the same individual, the eye with the more severely affected cornea had greater astigmatism (P = 0.002), even after the corneal erosion healed. Conclusions: Children with epiblepharon who needed surgery had greater with-the-rule astigmatism than controls. More severe corneal erosion was associated with higher astigmatism. Surgical correction of skinfold and promotion of reepithelialization did not attenuate astigmatism significantly.

Ischemic ophthalmoplegia in diabetes mellitus

Purpose : To analyze the natural course of ischemic diabetic palsies of the 3 rd , 4 th , and 6 th cranial nerves and their correlations with the status of diabetic control and retinopathy. Materials and methods : Twenty-nine patients with diabetic ophthalmoplegia, treated in Kaohsiung Medical University Hospital during the period 1996-1999, were included in the study. Data on clinical characteristics of the patients were obtained by chart review and the natural course of the cranial nerve palsies was analyzed. Laboratory studies, neuroimaging, and fundus studies were also performed. Results : Thirty-six episodes of ischemic ophthalmoplegia were recorded in 29 patients. Seventeen episodes of ophthalmoplgia occurred in patients with poor diabetic status. Third cranial nerve involvement occurred in 21 episodes, six of which (28.6%) had pupil involvement. Four patients had 4 th cranial nerve palsy and 11 episodes in nine patients involved 6 th cranial nerve palsy. Four patients had recurrent or alternate cranial nerve involvement, and three had simultaneous multiple cranial nerve involvement.The mean duration of paralysis was 2.8 ± 1.5 months with a significant difference ( p = 0.009) between the complete and incomplete palsy groups. Most of the cases had either no diabetic retinopathy ( No-DR )(55.2%) or only background diabetic retinopathy ( BDR )(34.5%). Except for average age, no significant difference was found between No-DR , BDR , and proliferative diabetic retinopathy ( PDR ) groups with respect to the duration of the palsies and fasting blood sugar levels. Age was significantly higher in the less severe diabetic retinopathy group (especially in the No-DR group). Conclusion : Cranial neuropathy with ophthalmoplegia is benign and self-limited. The oculomotor nerve was the most frequently involved in our group. Recovery time was dependent on ophthalmoplegia severity.The status of diabetic retinopathy and blood sugar level was not significantly related to the prognosis. Older diabetics (age > 63 years) had less severe retinopathy during attacks of ophthalmoplegia (p < 0.05). There might also be other risk factors, such as arteriosclerosis, inflammation, or anatomic variation, intervening in the pathogenesis of diabetic ophthalmoplegia.

Ophthalmologic abnormalities in high school students with mental retardation in Taiwan

BACKGROUND AND PURPOSE Visual and ocular disorders are common in mental retardation (MR), and can influence sensory-motor development and learning. This study investigated visual and ocular abnormalities in a population of high school students with MR. METHODS All students with MR in their first year at a special education high school who underwent ophthalmic examinations in December 2001 were included. Data were collected by retrospective review of hospital records and student health records. RESULTS A total of 68 students with MR, including 45 males and 23 females, completed ophthalmologic examinations. Abnormal ophthalmologic findings in these 68 students (15-23 years old) included astigmatism (74.4%), myopia (53.7%), amblyopia (29.3%), exodeviation (23.5%), anisometropia (22.0%), blepharoconjunctivitis (20.6%), hyperopia (18.2%), cataract (13.2%) and suspected glaucoma (11.8%). Amblyopia was mainly attributed by refractive errors and strabismus. Myopia was less prevalent than in the general population of the same age in Taiwan, but astigmatism and anisometropia were more prevalent. More than one-third of the exodeviations were large-angle exotropia. The presence and type of cataract were highly associated with Downs syndrome. CONCLUSION The prevalence of visual and ocular disorders in teenage and young-adult students with MR is high. Because these disorders can be detrimental to learning, early and regular ophthalmic examinations of children with MR are mandatory, with particular attention to screening for refractive error, amblyopia, strabismus and cataract and treatment of these conditions when identified.

Repetitive methylene blue-mediated photoantimicrobial chemotherapy changes the susceptibility and expression of the outer membrane proteins of Pseudomonas aeruginosa.

BACKGROUND Since bacterial multidrug efflux pumps mediate intracellular photosensitizer methylene blue, a change in the expression alters the susceptibility to photoantimicrobial chemotherapy (PACT) of Pseudomonas aeruginosa, which may occur following repetitive sublethal challenges. MATERIALS AND METHODS We performed 10 consecutive, methylene blue-mediated PACT on one antibiotic-sensitive strain and three antibiotic-resistant strains of P. aeruginosa. Following each therapy, the surviving bacteria were collected for subsequent PACT. The susceptibility was compared for the pre- and the post-treated strains following repetitive PACT. To explore the existence of efflux pumps, one of the inhibitors, namely Phe-Arg β-naphthylamide dihydrochloride (PAβN 25 μg/ml), was added. Profiles of outer membrane proteins were obtained for the pre-treated and the post-treated strains. RESULTS The susceptibility of PACT did not correlate with the antibiotic sensitivity. Following ten PACT, there was no significant change in susceptibility for three tested strains, except for one antibiotic-resistant strain, for which the 10th generation became less susceptible than the original one. With 2-D electrophoresis, a change in the expression of outer membrane proteins was observed. PAβN successfully increased the phototoxicity in all tested strains, especially the less PACT-susceptible 10th generation of the antibiotic-resistant strain. CONCLUSIONS Following repetitive challenges, PACT had a consistent antimicrobial effect on three strains; however, one antibiotic-resistant strain, which was the most vulnerable to PACT, became more resistant after consecutive challenges. In addition, the post-PACT strain had different expression of outer membrane proteins, providing further evidence view that repetitive PACT with methylene blue could change the expression of efflux pumps.

Treatment of early Acanthamoeba keratitis with alcohol-assisted epithelial debridement.

Purpose To study the safety and efficacy of treating early-stage Acanthamoeba keratitis (AK) with 20% alcohol-assisted epithelial debridement. Methods Four consecutive patients (2 wearing orthokeratology lenses and 2 wearing soft contact lenses) presented with pseudodendrites, radial keratoneuritis, and epithelial irregularities. Using a technique similar to laser-assisted subepithelial keratomileusis, we performed alcohol-assisted full-thickness debridement of the corneal epithelium and sent portions for smears, histopathologic and ultrastructural examinations, and culture for evidence of Acanthamoeba. Patients were then started on topical propamidine isethionate and 0.02% polyhexamethylene biguanide. Results Immediately after debridement, minimal underlying anterior stromal infiltrate or haze was seen. Dosages of antiamoebic agents were tapered as corneal defects reepithelialized (in 1–3 weeks) with no evidence of post-debridement corneal infection. At the final follow-up, 1 cornea was transparent and the other 3 corneas had very faint subepithelial haze. Cultures of all epithelial debridement specimens yielded Acanthamoeba trophozoites and cysts, and histopathologic and electron microscopic examinations revealed Acanthamoeba organisms within corneal epithelial layers. Conclusions Alcohol-assisted epithelial debridement facilitates detachment of the full-thickness corneal epithelial layer in a controlled manner and seems to be effective in the treatment of early-stage AK. Unlike the fragile fragmented specimens obtained by mechanical scraping without alcohol soaking, epithelial sheets detached easily and the architectures were well preserved, permitting histopathologic and ultrastructural examinations. Most importantly, 20% alcohol-assisted epithelial debridement did not prevent culturing of Acanthamoeba from the removed epithelial specimens.