Shawn H. Tsai

Visual Acuity, Optical Components, and Macular Abnormalities in Patients with a History of Retinopathy of Prematurity

PURPOSE To examine the optical components and spectral-domain optical coherence tomography (OCT) findings in children with a history of retinopathy of prematurity (ROP) and to identify any associations between the OCT findings and the visual acuities of the patients. DESIGN Prospective, case-controlled study. PARTICIPANTS AND CONTROLS Children who were between 6 and 14 years of age were divided into the following 4 groups: Patients with a history of threshold ROP who had been treated using laser therapy or cryotherapy (group 1), patients with regressed ROP who had not received any treatment (group 2), patients who were born prematurely but who had no history of ROP (group 3), and normal full-term children (group 4). The posterior poles of the eyes of all of the patients seemed to be normal. METHODS Visual acuities, optical components, and macular thicknesses were measured in 4 groups of patients, and comparisons between the groups were made. Macular thicknesses were measured using OCT. MAIN OUTCOME MEASURES Visual acuity (VA), optical components, and OCT findings. RESULTS We enrolled 133 patients in the study. Patients in group 1 had significantly thicker foveas than the other patients, as demonstrated by OCT, and this finding was negatively correlated with gestational age. The incidence of abnormal foveal contours among patients in group 1 was significantly higher than among the rest of the patients. Retention of the inner retinal layers was noted in group 1 patients; however, the structure of the outer retina remained intact. Greater degrees of myopic shift and astigmatism, steeper corneal curvatures, shallower anterior chamber depths, and thicker lenses were noted in previously treated ROP patients. These findings corresponded with poor VA and high refractive errors in group 1 patients. CONCLUSIONS Patients with a history of threshold ROP are more likely to show abnormal foveal development and have a poorer visual prognosis than other patient groups despite a fundus with no macular dragging, disc dragging, or retinal detachment. A steeper corneal curvature, shallower anterior chamber, and greater lens thickness are the main changes in the optical components in these patients.

Choroidal Thickness in Patients With a History of Retinopathy of Prematurity

IMPORTANCE The cause of reduced vision in patients with a history of retinopathy of prematurity (ROP) is not yet fully understood. The role of the choroid in ROP remains unknown and existing studies of choroidal thickness in patients with a history of ROP are limited. It might be helpful to understand the association of the choroid with ROP by measuring the choroidal thickness in patients with a history of ROP and correlating these findings with the visual outcome of these patients. OBJECTIVE To examine choroidal thickness by spectral-domain optical coherence tomography in children with a history of ROP and assess the impact of choroidal thickness on visual acuity. DESIGN A prospective cross-sectional analysis from August 2011 to September 2012. SETTING Institutional referral centers. PARTICIPANTS Children aged 6 to 14 years with a history of ROP were classified into the following 2 groups: patients with a history of threshold ROP and treatment with laser or cryotherapy (treated group) and those with regressed ROP who had not received any treatment (nontreated group). All of the patients had a normal-appearing posterior pole. INTERVENTION Examinations of visual acuity, refractive errors, and optical components and measurement of choroidal thickness. MAIN OUTCOMES AND MEASURES Best-corrected visual acuity, optical components, and optical coherence tomography findings. RESULTS In total, 49 patients were enrolled in the study. Patients in the treated group had a significantly thinner choroidal thickness than the patients in the nontreated group after adjusting for age, axial length, and spherical power. Choroidal thickness was found to be positively associated with spherical power and spherical equivalent and negatively associated with axial length and vitreous depth. In addition, a thin choroidal thickness was associated with a worse best-corrected visual acuity. CONCLUSIONS AND RELEVANCE Choroidal thickness is thinner in patients with threshold ROP compared with the patients with spontaneously regressed ROP. A thinner choroid is associated with worse vision in these patients. This study might imply the association of choroid circulation with ROP.

Characteristics of Peripapillary Choroidal Cavitation Detected by Optical Coherence Tomography

PURPOSE To evaluate the clinical features of peripapillary choroidal cavitation (PCC) detected by optical coherence tomography (OCT). DESIGN Retrospective, observational case series. PARTICIPANTS One hundred twenty-two eyes from 83 patients diagnosed with PCC by OCT database review were included in this study. METHODS Stereoscopic color fundus photographs from eyes with PCC were reviewed by 2 independent ophthalmologists. They were masked to the refractive error, axial length, and OCT findings. MAIN OUTCOME MEASURES Chart review and data analysis included gender, age, best-corrected visual acuity (BCVA), refractive error, axial length, clinical appearance of the peripapillary area, and associated funduscopic abnormalities. RESULTS One hundred twenty-two eyes with PCC from 83 patients were analyzed. Among the patients, 41.8% were men and 58.2% were women. The mean age was 48.2 ± 12.6 years and mean BCVA in logarithm of the minimum angle of resolution units was 0.23 ± 0.43. The mean refractive error in spherical equivalent was -9.03 ± 5.11 diopters (D) and mean axial length (AL) was 27.36 ± 2.09 mm. With respect to refractive error, 90 eyes (73.8%) were highly myopic (≥-6.00 D), 24 eyes (19.7%) had low myopia (<-6.00 D), 5 eyes (4.1%) were emmetropic (1.00 to -1.00 D), and 3 eyes (2.6%) were hyperopic (>1.00 D). Forty eyes (32.8%) with PCC had AL of less than 26.50 mm (mean, 25.11 ± 1.07 mm; range, 22.51-26.42 mm). Patients with eyes with PCC that had low myopia, were emmetropic, and were hyperopic also were significantly older than patients with highly myopic eyes (P<0.05). Stereoscopic fundus photographs demonstrated a yellow-orange, localized, well-circumscribed peripapillary lesion in 57 (46.7%) eyes with PCC. A PCC with opening was observed in 14 (26.4%) of 53 eyes with excavated myopic conus and in 5 (7.2%) of 69 eyes without excavated myopic conus (P<0.05). CONCLUSIONS This study demonstrated that peripapillary choroidal cavitation is common and not exclusive to highly myopic eyes. The funduscopic finding of a yellow-orange peripapillary abnormality may not be evident in all eyes with demonstrable PCC by OCT. Although its pathogenesis and pathologic significance require further investigation, PCC may be a degenerative change in aging eyes.

Natural history of retinopathy of prematurity: two-year outcomes of a prospective study.

Purpose: To investigate the 2-year outcomes of the natural history of retinopathy of prematurity (ROP) in Taiwan. Methods: A prospective study was conducted at two tertiary medical centers. Premature infants were screened and examined for ROP. The postmenstrual ages of developing each stage of ROP and the associated risk factors were recorded. Results: A total of 698 infants were included. The incidences of ROP and treatment-requiring ROP in all patients with ROP were 29.7% and 37.2%. When only including patients with birth weight of 1,250 g or less, the incidences were 62.2% and 39.1%, respectively. In patients with ROP with birth weight over 1,250 g, 25% of them developed treatment-requiring ROP. The median postmenstrual ages for the development of Stage 1, Stage 2, and Type 1 ROP were 33.0, 34.0, and 34.7 weeks, respectively. Gestational age at birth and birth weight were the most important factors associated with treatment-requiring ROP (hazard ratios of 0.3 and 0.6). Conclusion: Our hospital-based study reveals an earlier postmenstrual age of developing ROP in this Asian population than in the Early Treatment for ROP study. Infants with birth weight over 1,250 g could still develop treatment-requiring ROP. Suboptimal oxygen control, different genetic dispositions among different races, inconsistencies in ROP diagnosis, and earlier screening might account for such a phenomenon.

Half-Dose Verteporfin Combined with Half-Fluence Photodynamic Therapy for Chronic Central Serous Chorioretinopathy

PURPOSE This study evaluated the safety and efficacy of half-dose verteporfin combined with half-fluence photodynamic therapy (half-half photodynamic therapy (PDT) for chronic central serous chorioretinopathy (CSC). METHODS This was a retrospective case series. Fourteen eyes with chronic CSC receiving half-half PDT were included in group 1. Another 28 eyes receiving half-dose verteporfin combined with standard fluence PDT were included in group 2 as a control group. Main outcome measures were the success rates, major complications, best-corrected visual acuity (BCVA), and central subfield foveal thickness (CFT) on optical coherence tomography (OCT) at 6 months in both groups. Success of treatment was defined as complete resolution of subretinal fluid on OCT after treatment without recurrence. RESULTS There was no significant difference between groups in their age, gender, duration of symptoms, baseline BCVA, baseline CFT, PDT spot size, and follow-up duration. The success rate was 64% (9/14 eyes) in group 1 and 93% (26/28 eyes) in group 2 at 6 months (P=0.031). No major complications were found in either group. Mean CFT showed significant reduction at 6 months in both groups (-115 μm and P<0.001 in group 1; -150 μm and P<0.001 in group 2). The mean BCVA in group 2 improved significantly (P<0.001) at 6 months. The mean BCVA in group 1 showed a trend of improvement but was not statistically significant (P=0.25) at 6 months. CONCLUSIONS Half-half PDT is a feasible treatment for chronic CSC. However, there was a lower success rate at 6 months compared with the control group.

Pigment epithelium‑derived factor short peptides facilitate full‑thickness cutaneous wound healing by promoting epithelial basal cell and hair follicle stem cell proliferation

A previous study by our group showed that a 44-amino-acid fragment of pigment epithelium-derived factor (PEDF) facilitated corneal epithelial wound healing. In the present study this fragment was shortened to obtain peptides of 18, 20 and 29 amino acids in length, and their promoting effects on the healing of full-thickness skin wounds were assessed. Peptides were delivered periodically by topical application to punch wounds of mice. The wound healing speed was evaluated by measuring the reduction of wound areas at 4 and 7 days after injury. Histological analysis with Massons trichrome staining was used to confirm epithelialization and dermal collagen deposition. Proliferation of epithelial basal cells was documented by 5-bromo-2′-deoxyuridine incorporation. Hair follicle stem cells were identified by immunostaining for leucine-rich repeat-containing G protein-coupled receptor 6. The results indicated that the 20- and 29-amino-acid short peptides significantly reduced the time required for wound healing compared to the vehicle. Histological analysis confirmed faster epithelial cell coverage of open wounds. Treatment with the PEDF peptide fragments also contributed to granulation, tissue formation by increasing the fibroblast population and enhancing collagen deposition in the dermis. Wounds treated with PEDF peptide fragments contained more basal cells proliferated in the epithelium. Moreover, hair follicle stem cells were also stimulated to proliferate by peptide exposure. In conclusion, the present study reported the identification of two short peptides that can enhance the healing of full-thickness skin wounds following topical application. The underlying mechanisms may involve activation of basal cell proliferation and mobilization of hair follicle stem cells.

Eclipse photodynamic therapy for a presumed peripapillary metastatic tumor.

PURPOSE We report a successful use of a modified photodynamic therapy (PDT) termed Eclipse PDT in treating a patient with peripapillary metastatic choroidal tumor. METHODS Optic disk protection effect was measured with different colored paper disk attached to the reflecting mirror of the laser machine. RESULTS Black paper disk was chosen to perform Eclipse PDT because of its maximal blocking effect. A patient with peripapillary metastatic choroidal tumor was treated using this method, and the postoperative outcome was favorable, with improvement in visual acuity and resolution of subretinal fluid. CONCLUSION With the new technique, treatment can be modified according to the lesions shape and location without damaging the optic disk. Eclipse PDT can further extend the indication of PDT treatment to peripapillary choroidal neovascularization as well as choroidal tumors close to the optic disk.

Acquired Ocular Toxoplasmosis in a Patient with Sulfa Allergy-A Case Report

Purpose: To report a rare case of acquired ocular toxoplasmosis in a patient with sulfa allergy.Method: A case report.Result: We report the case of a 55- year-old woman who presented with vitritis and focal chorioretinitis in right eye without a pre-existing scar. She had higher serum titers of anti-toxoplasma immunnoglobluin (Ig)M and IgG, leading to a diagnosis of acquired ocular toxoplasmosis. Because the patient had sulfa allergy, she underwent clindamycin therapy instead for 1 month, but the ocular lesion recurred. Subsequently, she underwent combination therapy with pyrimethamine, azithromycin, folic acid and corticosteroids for 1 month. The chorioretinal lesion reduced to a pigmented scar and the best corrected visual acuity of the right eye returned to 1.0 without recurrence of ocular lesions for 6 months.Conclusion: Acquired ocular toxoplasmosis is a rare disease. Laboratory tests for anti-toxoplasma antibodies can be useful in establishing diagnosis in such cases. Sulfadiazine can be successfully replaced by azithromycin in combination therapy for patients with sulfa allergy.