Kenneth Kw Li

Choroidal evaluation using enhanced depth imaging spectral-domain optical coherence tomography in Vogt-Koyanagi-Harada disease.

Background: Current imaging modalities used in the evaluation of Vogt-Koyanagi-Harada (VKH) disease include ultrasound, fluorescein angiogram, indocyanine green angiography, and optical coherence tomography (OCT). However, they all fail to give detailed information on the ultrastructural changes of the choroid. A recent technique using OCT termed “enhanced depth imaging” produces high-resolution cross-sectional images of the whole thickness of the choroid. The purpose of the study was to describe a novel imaging finding in the choroid in cases of VKH uveitis and to assess for interobserver agreement of this new physical sign. Methods: This is an age-matched, sex-matched, and spherical equivalent-matched, case-control, cross-sectional study. Six VKH patients in acute and convalescent stages underwent choroidal imaging using enhanced depth imaging spectral-domain OCT imaging. A horizontal enhanced depth imaging spectral-domain OCT scan across the fovea was selected for each eye and was compared with a scan from an age-matched, sex-matched, and spherical equivalent-matched control subject. A loss of focal hyperreflectivity, represented by a decrease in the number of hyperreflective dots in the inner choroid, was observed. This finding was assessed for interobserver agreement using five masked observers. Mean observed agreement and multirater kappa statistics (κ) were calculated. The average choroidal thickness was also calculated and compared among acute-phase VKH patients, convalescent-phase VKH patients, and control subjects. Results: There was a significant loss of focal hyperreflectivity in the inner choroid of VKH patients compared with control subjects in both acute and convalescent stages. Analysis revealed substantial interobserver agreement on this finding. The mean observed agreement was 95%, and the overall kappa coefficient (κ) was 0.80 (P < 0.01). The choroid of acute-phase VKH patients was thicker than that of convalescent-phase patients by 151 μm (P = 0.043) and control subjects by 137 μm (P = 0.001). There was no statistically significant difference in thickness between convalescent eyes and controls. Conclusion: Enhanced depth imaging spectral-domain OCT highlights a loss of focal hyperreflectivity in the inner choroid of eyes with VKH, a feature that is consistently observed by independent masked observers. The presence of this feature in both acute and convalescent phases could represent permanent structural change to small choroidal vessels caused by VKH uveitis.

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

OBJECTIVEnTo study the safety and efficacy of photodynamic therapy (PDT) with verteporfin in treating subfoveal choroidal neovascularization (CNV) of idiopathic cause.nnnDESIGNnA prospective, noncomparative, consecutive, open-label, two-center, interventional case series.nnnPARTICIPANTSnPatients 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.nnnMETHODSnSeventeen 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.nnnMAIN OUTCOMES MEASURESnThe 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.nnnRESULTSnSeventeen 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.nnnCONCLUSIONSnPDT 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.

Retinal complications after cataract extraction in patients with high myopia

OBJECTIVEnTo assess risk factors and incidence of retinal complications after cataract extraction in patients with high myopia.nnnDESIGNnRetrospective, noncomparative case series.nnnPARTICIPANTSnOne hundred eighteen patients with highly myopic eyes who had an axial length of 26 mm or more (mean axial length, 30.13 +/- 2.08 mm) and who underwent cataract surgery over a period of 6 years were studied.nnnINTERVENTIONnPatients underwent cataract extraction either by extracapsular cataract extraction (ECCE) or phacoemulsification. Prophylactic argon laser photocoagulation was performed in 13 eyes for retinal tears recognized before surgery and in 13 eyes after surgery; neodymium:YAG (Nd:YAG) laser capsulotomy was performed for patients with posterior capsule opacification (PCO) that affected the vision.nnnMAIN OUTCOME MEASURESnIncidence of retinal detachment and PCO and percentage of prophylactic argon laser or of Nd:YAG laser treatments.nnnRESULTSnOf the 118 eyes, 73 (61.9%) underwent ECCE and 45 (38.1%) underwent phacoemulsification. Posterior capsule opacification was the most common complication and was found in 30 eyes (25.4%). Thirteen patients (11%) received prophylactic laser treatment for retinal tears before cataract operation, and 13 more patients (11%) had postoperative retinal tears requiring laser treatments. None of these patients developed retinal detachment. Two patients (1.69%) developed retinal detachment within 6 months after their operations. There were no intraoperative complications, and postoperative Nd:YAG capsulotomy was not performed in these two patients.nnnCONCLUSIONSnActive searching and prophylactic laser treatments for retinal tears developed before and after cataract extraction in patients with high myopia are recommended. This may lower the incidence of postoperative retinal detachment.

Photodynamic Therapy in Macular Diseases of Asian Populations : When East Meets West

PurposeWe reviewed the indications, safety, and efficacy of photodynamic therapy with verteporfin in various macular diseases and vasculopathies, which are common in Asian populations, and compared the outcomes of photodynamic therapy in Asian patients with the outcomes in Caucasian patients.MethodsRelevant clinical and laboratory original articles, case reports, and review articles that have been published in the literature between January 1999 and October 2004 were searched in Medline. The potential differences in the response to photodynamic therapy between Asian and Caucasian patients were evaluated. Articles in foreign languages with English abstracts were included.ResultsMacular diseases commonly seen in Asian populations, including choroidal neovascularization (CNV) of age-related macular degeneration, secondary to pathologic myopia or from an idiopathic cause, and choroidal vasculopathies such as central serous chorioretinopathy and polypoidal choroidal vasculopathy were included in the review. The results were tabulated and the differences with Caucasian populations were compared and highlighted.ConclusionPhotodynamic therapy has been found to be an effective and noninvasive treatment for various subfoveal CNV and choroidal vasculopathies of the macula. Diverse behavior in different ethnic groups is observed. Jpn J Ophthalmol 2006;50:161–169

Intravitreal triamcinolone for diabetic macular oedema in Chinese patients: six-month prospective longitudinal pilot study

Aim:u2002To evaluate the safety and efficacy of intravitreal triamcinolone (IVTA) in Chinese patients with diabetic clinical significant macular oedema (CSMO).

Pars plana vitrectomy in the management of retained intravitreal lens fragments after cataract surgery

Purpose: To assess the outcome of patients who underwent pars plana vitrectomy for retained lens fragments after cataract surgery.

Use of intravitreal triamcinolone acetonide injection in unilateral idiopathic juxtafoveal telangiectasis

Idiopathic juxtafoveal telangiectasis (IJT) is one of the primary retinal telangiectasia that can result in visual impairment attributed to resultant cystoid macular oedema and rarely, choroidal neovascularization. The authors herein report successful treatment using intravitreal triamcinolone acetonide in a case of unilateral IJT that did not respond to prior laser photocoagulation. Serial optical coherence tomography was used to monitor the effectiveness of intravitreal triamcinolone acetonide in the treatment of IJT.

Avastin in myopic choroidal neovascularisation: is age the limit?

In this study, PDT was shown to be effective in preventing visual loss fewer than eight letters in pathologi- cal myopia in the first year when com- pared with sham treatment. 10 However, 17 They found that patients under the age of 40 had significant better visual outcome than patients over the age of 40. Their results need to be interpreted carefully, as they included both juxtafoveal and sub- foveal cases. The authors nonetheless raised the important point that the visual prognosis of CNV secondary to patholo- gical myopia was not always consistent. The angiographic features of the CNV in patients over the age of 40 had a more profuse angiographic leakage. Other inves- tigators have studied the effect of age on the visual outcome of treatment of CNV secondary to pathological myopia with PDT. Axer-Siegel et al, in a retrospective study, found that 50% of the older age group and 20% of the younger age group had visual loss of 15 letters or more, and the difference was significant; however, 8% of the younger patients in the series of Axer-Siegel et al continued to lose 15 or more letters despite treatment with PDT. 18

Photodynamic therapy with verteporfin in laser-induced choroidal neovascularization

PURPOSEnTo report a case of laser-induced choroidal neovascularization (CNV) treated with verteporfin photodynamic therapy.nnnDESIGNnInterventional case report.nnnMETHODSnA patient developed CNV in the macular area of the left eye 2 years following grid laser for macular edema secondary to branch retinal vein occlusion.nnnRESULTSnThe CNV was controlled with one session of photodynamic therapy. Lesion decreased in size, contracting to a smaller subretinal fibrotic scar. Vision improved from 20/200 to 20/100, and there was no recurrence at 2-year follow-up. No complications were encountered.nnnCONCLUSIONnLaser-induced CNV can be safely and effectively treated by photodynamic therapy.

Factors associated with variability in response of diabetic macular oedema after intravitreal triamcinolone

Purpose:u2002 To identify factors associated with variability in anatomical and functional response of diabetic macular oedema (DMO) after 4u2003mg of intravitreal triamcinolone acetonide (ivTA), and for recurrence of macular oedema.