W-M Chan

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 choroidal neovascularisation of pathologic myopia in Chinese eyes: a prospective series of 1 and 2 year follow up

Aims: To evaluate the visual and fluorescein angiographic outcomes of photodynamic therapy (PDT) with verteporfin in patients with subfoveal choroidal neovascularisation (CNV) caused by pathologic myopia in the Chinese. Methods: Prospective, non-comparative, two centre interventional study. Patients with CNV secondary to pathologic myopia of Chinese ethnicity were recruited and treated with a standard regimen of PDT with verteporfin. Results of this study in Chinese eyes with pigmented retinal pigment epithelium were compared with those from the Verteporfin in Photodynamic Therapy (VIP) Study of predominantly white eyes. Results: Thirty one and 22 eyes that completed the 12 month and 24 month follow up studies respectively were analysed. The mean and median best corrected visual acuities (BCVA) could be maintained at the baseline level at the 12 month and 24 month visits. Fourteen (63.6%) eyes had stable or improved BCVA at 24 months and six (27.3%) of them had a moderate gain in vision (improved by three or more lines). Visual results were comparable with that of the VIP study, but the average accumulative PDT treatments required in one and two years were 1.7 and 2.3 respectively, which were significantly less than 3.4 and 5.1 treatments in VIP study. Mean logMAR BCVA of the younger age group (<55 years) at 24 months was 0.41 (SD 0.29), which was significantly better than the older age group (⩾ = 55 years) of 0.82 (SD 0.40) (Mann-Whitney U test, p = 0.029). Conclusions: PDT using the predetermined treatment protocol has achieved similar visual outcomes in the Chinese population as in white people with subfoveal myopic CNV over a 2 year study period. The complete cessation of CNV leakage can be accomplished, on average, with fewer PDT retreatments than reported in the VIP study. The disparity may be due to ethnic differences in these two populations.

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.

Time taken to do external and endoscopic endonasal dacryocystorhinostomy (DCR) surgery

present in the anterior chamber. A thin-walled bleb existed at the upper side of the conjunctiva. However, no opaque or leakage was seen in the bleb. The fundus was invisible because of extreme vitreous opacity. A pars plana vitrectomy was conducted with a tentative diagnosis of bleb-related endophthalmitis. The retina was mostly intact and several exudative lesions with white vessels were observed at the nasal and inferior mid-peripheries of the fundus (Figure 1). Suspecting of a viral infection, vitreous humour was sampled. Whereas the culture examination resulted in no bacterial growth, varicella-zoster virus (VZV)specific DNA was detected by polymerase chain reaction (PCR). The patient was diagnosed as ARNS caused by VZV. Intravenous infusion of acyclovir of 750 mg/day and oral corticosteroid of 40 mg/day with topical corticosteroid were initiated. The white-exudative lesions gradually subsided and became necrotic degeneration. Visual acuity improved up to 160/200 in the right eye 2 months after vitrectomy. To our knowledge, this is the first description of ARNS mimicking bleb-related endophthalmitis. We should be aware that viral infection could masquerade clinical features resembling a bacterial endophthalmitis.

Preoperative videotape sessions and patient satisfaction with cataract surgery

We read with interest the article by Pager.1 The study showed that a preoperative videotape session describing the experience of day stay cataract surgery resulted in a significant increase in overall satisfaction during the immediate postoperative period. Patient satisfaction has drawn increasing attentions in all field of medicine for medical, financial, and litigation reasons. Age, types …

Characteristics and surgical outcomes of paediatric retinal detachment

The therapy of varicella zoster virus (VZV) acute retinal necrosis syndrome by oral valganciclovir was recently reported by Savant et al. This therapy was given to a 30-year-old woman as an alternative treatment option in herpes viral retinitis. Oral therapy has the great advantage to avoid prolonged intravenous (i.v.) drug administration and hospital admission. Valganciclovir, a L-valyl ester prodrug with improved bioavailability, is hydrolysed in the gut and liver and produces ganciclovir exposure similar to i.v. ganciclovir. Ganciclovir differs from acyclovir by the lack of an hydroxyl group on the acyclic side chain, with enhanced activity against cytomegalovirus (CMV), but similar activity against herpes simplex and VZ virus. However, this modification is associated with cytotoxicity and serious adverse effects in humans including neutropenia, anaemia, diarrhoea. In addition, it has been shown to be mutagenic, teratogenic, and carcinogenic in animal models. Ganciclovir has also the potential to permanently affect fertility in animal and humans (Product monograph, Roche Basel, CH, Switzerland). Indeed, ganciclovir and valganciclovir are exclusively registered for the treatment of life or sight-threatening CMV infections. Our treatment option in acute retinal necrosis syndrome is rather high dosage oral valaciclovir. The L-valylester valaciclovir offers an oral bioavailability of 54.2%, which is about 4.5 times higher than oral aciclovir. The recommended dosage in VZV infection is valaciclovir 1000 mg t.i.d. that produces AUC similar to i.v. aciclovir at the dosage of 5 mg/kg t.i.d. However, pilot clinical studies could demonstrate that higher dosage of oral valaciclovir 2000 mg 4 times daily could produce the daily AUC of 109 mg h, which was close to the one obtained by i.v. aciclovir at the dosage of 10 mg/kg t.i.d. (AUC of 107 mg h). The limit of the administration of high dosage of valaciclovir is mostly the renal and CNS toxicity of the drug that can be avoided by adequate hydratation and dose adjustment to creatinine clearance. These high valaciclovir dosages have been indeed well tolerated when prescribed to kidney transplant recipients for the prophylaxis of CMV disease, with only a slight excess in CNS adverse effects such as hallucination and confusion. We suggest that higher dosage of oral valaciclovir could be a good alternative therapy to i.v. aciclovir. References