Barbara S.M. Tam

Choroidal vascular remodelling in central serous chorioretinopathy after indocyanine green guided photodynamic therapy with verteporfin: a novel treatment at the primary disease level.

Aims: To evaluate the changes in the choroidal vasculature in central serous chorioretinopathy (CSC) after photodynamic therapy (PDT) with verteporfin and to assess its potential role as a treatment option. Methods: A prospective, non-comparative, interventional study was performed in eyes with persistent CSC or chronic CSC that had fluorescein leakage at the fovea. All eyes received one single session of PDT with verteporfin (6 mg/m2 body surface area) followed by application of 50 J/cm2 laser at 689 nm. The laser spot size was guided by findings in ICG-A. Results: Six eyes from six patients with a mean follow up of 12.7 months were analysed. Narrowing of the original dilated choroidal vessels and decrease in extravascular leakage could be demonstrated in all (100%) PDT treated eyes. 3 months after PDT, the mean diameter of the dilated choroidal vessel reduced from 546 μm to 371 μm (p = 0.028). Five (83%) patients had improvement in visual symptoms and best corrected visual acuity. Fluorescence leakage stopped at the 1 month follow up in five eyes (83%) and at 3 months in all six eyes (100%). One eye developed choroidal neovascularisation at 3 month follow up. There was no other serious ocular or systemic complication. Conclusions: PDT is successful in stopping the fluorescein leakage in all six patients without recurrence of CSC. The ICG-A findings of choroidal vascular remodelling and decreased choroidal permeability after PDT are encouraging. As the sample size is small and the mean follow up period is short, further trials of PDT with verteporfin for CSC are required to address the optimal parameters in ensuring longer term safety and efficacy outcome.

Photodynamic therapy with verteporfin for subfoveal idiopathic choroidal neovascularization: one-year results from a prospective case series.

OBJECTIVE To study the safety and efficacy of photodynamic therapy (PDT) with verteporfin in treating subfoveal choroidal neovascularization (CNV) of idiopathic cause. DESIGN A prospective, noncomparative, consecutive, open-label, two-center, interventional case series. PARTICIPANTS Patients aged 50 years or younger with the diagnosis of idiopathic CNV by exclusion of other related causes together with the CNV extending under the geometric center of the foveal avascular zone. METHODS Seventeen eyes from 17 patients received PDT with verteporfin according to a standardized protocol. Retreatment was considered if fluorescein leakage from the CNV was shown in fluorescein angiography at every 3-month follow-up. The visual, clinical, and angiographic responses were observed. Complications from treatment were monitored and documented. MAIN OUTCOMES MEASURES The changes in the best-corrected visual acuity (BCVA) at the 1-year follow-up. The proportion of patients with improved (gained 2 lines or more), stable, and dropped (lost 2 lines or more) vision and the mean number of treatments required during the 1-year interval were measured. Complications were monitored and tabulated. RESULTS Seventeen eyes with complete 1-year follow-up were analyzed. The mean logarithm of the minimum angle of resolution BCVA improved from 0.64 to 0.41 (Wilcoxon signed-ranks test, P = 0.007). Sixteen eyes (94%) had stable or improved vision. Only one patient (6%) had moderate loss of vision. The mean number of PDT treatment was 1.8 per eye over the 1-year period. Patients with smaller lesion size or active vascular CNV on presentation were more likely to have a final BCVA of 20/100 or better (Fishers exact test, P = 0.006 and P = 0.015, respectively). No serious local or systemic complications were encountered. CONCLUSIONS PDT seems to be a promising treatment strategy in achieving a stable or improved vision for subfoveal idiopathic CNV. The treatment was well tolerated. Further studies and longer follow-up are warranted to assess the long-term safety and efficacy of PDT compared with observation or other treatment modalities.

Prevalence and characteristics of peripheral retinal degeneration in chinese adults with high myopia : A cross-sectional prevalence survey

Purpose. The purpose of this study was to study the prevalence of peripheral retinal findings in adult Chinese patients with high myopia (refraction ≤-6.00 D) and to investigate the correlation between the retinal lesions and the severity of myopia or axial length. Methods. A cross-sectional prevalence survey screening was conducted in high ethnic Chinese myopes with refractions equal to or less than -6.00 D. The examinations included cycloplegic refraction, A and B scan ultrasonography, and retinal examinations by indirect ophthalmoscopy with scleral indentation and Goldmann three-mirror contact lens examination. Results. Two hundred thirteen eyes in 213 patients with a mean refraction of -10.10 ± 4.23 D (range = -6.00 to -27.00 D) were examined. The mean axial length was 26.69 ± 1.68 mm (range = 25.18–33.62 mm) and the mean age was 33.5 ± 10.6 years (range = 18–73 years). The most common peripheral retinal finding was pigmentary degeneration (51.2%), followed by lattice degeneration in 12.2% and retinal holes in 7.5% of eyes. A positive correlation was noted between axial length and the lesions of pigmentary degeneration and pavingstone degeneration. The prevalence of retinal holes was 6.4% and 30.0% in eyes with axial length of <30 mm and ≥30 mm, respectively (chi-squared test, p = 0.006). Conclusion. A high prevalence of peripheral retinal degenerations was found in adult Chinese high myopes. The presence of retinal holes was positively correlated with very high myopia of an axial length of ≥30 mm.

Transient Increase in Intraocular Pressure during a Dose-Tapering Regime of Systemic Dexamethasone in Preterm Infants

PURPOSE To determine the intraocular pressure (IOP) profile during and after systemic dexamethasone treatment in preterm very low birth weight (VLBW; <1500 g) infants. DESIGN A cohort study at a university-affiliated tertiary neonatal center. PARTICIPANTS Twenty-seven VLBW infants who received a 3-week dose-tapering course of systemic dexamethasone for treatment of bronchopulmonary dysplasia were consecutively enrolled over a period of 32 months. METHODS Intraocular pressure was assessed using a handheld tonometer immediately before (week 0), during (weeks 1 and 3), and after (weeks 5, 7, and 9) commencement of the dexamethasone course. The mixed-effects models were used to evaluate the longitudinal IOP measurements at different time points. MAIN OUTCOME MEASURES To assess the magnitude and duration of increase in IOP during systemic corticosteroid treatment. RESULTS The IOP at week 1, while the infants were receiving the maximum dose of dexamethasone (0.6 mg/kg/day), was significantly higher than (1) the pretreatment IOP at week 0 (mean [+/- standard deviation]: 19.7 [+/-3.7] vs. 16.4 [+/-3.7] mmHg, respectively) (P<0.0001), (2) the IOP when the infants were receiving the minimum dose of dexamethasone (0.15 mg/kg/day) at week 3 (19.7 [+/-3.7] vs. 15.8 [+/-4.3] mmHg) (P<0.0001), and (3) the IOP after the dexamethasone course had been stopped between week 5 and week 9 (19.7 [+/-3.7] vs. 16.0 [+/-4.0], 15.3 [+/-3.5], and 14.5 [+/-3.3] mmHg for weeks 5, 7, and 9, respectively) (P<0.0001 for all comparisons). In contrast, there was no significant difference between the pretreatment IOP (week 0) and IOP at week 3, 5, 7, or 9 (P = 0.07-0.62) and in the IOP between week 3 and week 5, 7, or 9 (P = 0.27-0.75). CONCLUSIONS The use of a dose-tapering regime of dexamethasone is associated with transient increase of IOP. As IOP was significantly raised during the high-dose but not the low-dose treatment period, we speculate that the physiologic or stress dose of corticosteroids commonly advocated for treatment of serious neonatal conditions should be safe and unlikely to cause significant ocular hypertension in preterm infants.

Precautions in ophthalmic practice in a hospital with a major acute SARS outbreak: an experience from Hong Kong

Many new infectious diseases in humans have been derived from animal sources in the past 20 years. Some are highly contagious and fatal. Vaccination may not be available and antiviral drugs are not effective enough. Infectious control is important in clinical medicine and in Ophthalmology. Severe acute respiratory syndrome (SARS), as an example, is a highly contagious respiratory disease that has recently been reported in Asia, North America, and Europe. Within a matter of weeks, the outbreak has evolved to become a global health threat and more than 30 countries have been afflicted with a novel Coronavirus strain (SARS-CoV) that is the aetiologic agent of SARS. The primary route of transmission of SARS appears involving close person-to-person contact through droplets. Ophthalmologists may be particularly susceptible to the infection as routine ophthalmic examinations like direct ophthalmoscopy and slit-lamp examination are usually performed in a setting that has close doctor–patient contact. Being the Ophthalmology Department of the only hospital in the world that has just gone through the largest outbreak of SARS, we would like to share our strategy, measures, and experiences of preventing contracting or spreading of SARS infection as an infection control model. SARS is one of the many viruses against which personnel will need protecting in an ophthalmic setting. The experiences attained and the measures established might also apply to other infectious conditions spreading by droplets such as the avian influenza with H5N1.

Combined cataract extraction and submacular blood clot evacuation for globe perforation caused by retrobulbar injection

A 45-year-old woman, originally scheduled for cataract surgery in the left eye, was referred for management of a globe perforation noticed after the retrobulbar injection of an anesthetic solution. There was a moderate degree of vitreous hemorrhage, and initial visual acuity was hand movement. A submacular blood clot of about 4-disc diameter was detected when the vitreous hemorrhage gradually cleared. One week after the incident, combined phacoemulsification, intraocular lens implantation, pars plana vitrectomy, and submacular clot removal using tissue plasminogen activator (tPA) as an adjunct were performed. Recovery was uneventful. At the last follow-up 6 months after surgery, best corrected visual acuity was 20/30.