Surgical management and immunohistochemical study of corneal plaques in vernal keratoconjunctivitis.

Two children with shield ulcer in vernal keratoconjunctivitis unresponsive to steroid therapy received plaque removal by superficial keratectomy, followed by amniotic membrane transplantation (AMT). Hematoxylin and eosin staining of the excised corneal specimen revealed a thick layer of eosinophilic material attached to the Bowman's layer. These deposits were positive for eosinophil granule major basic protein, as confirmed by an immunohistochemical study. The shield ulcer healed after the amniotic membrane was removed. No recurrent corneal plaque developed, although corneal opacity complicated in both cases. Lamellar keratectomy with AMT offers an effective management by removing the cytotoxic plaques and protecting the denuded stroma from deposition of inflammatory debris.

Orbital development in survivors of retinoblastoma treated by enucleation with hydroxyapatite implant.

AIMS: To determine the impact of enucleation with hydroxyapatite implant on bony orbital development in survivors of retinoblastoma (RB) by measuring orbital volume based on CT imaging. METHODS: The authors used CT images obtained at a median age of 6 years to measure orbital volume of RB and contralateral orbits in 18 patients who underwent enucleation with hydroxyapatite implant for RB. Comparison of the orbital volume of RB and contralateral orbits was done using the Wilcoxon rank sum test. RESULTS: The mean age at diagnosis and operation was 29±23 months, and the mean follow-up was 49±31 months. The mean volume difference between RB and contralateral orbits was 0.93±1.13 cm(3). RB orbits with hydroxyapatite implant were statistically significantly smaller than contralateral orbits (p=0.002). The age at operation was significantly negatively correlated with orbital volume difference (p=0.033). Orbital volume differences for children treated by enucleation before the age of 12 months were also statistically significantly larger than those treated later. (p=0.03). CONCLUSION: Significant orbital growth retardation remained after enucleation, even with a hydroxyapatite implant for the RB orbit. Orbital growth retardation was correlated with operation age and also more prominent in children treated in the first year of life.

Pharmacokinetics of nifedipine in Taiwanese.

To elucidate the pharmacokinetics of nifedipine in Taiwanese, a retrospective review of nifedipine bioequivalence studies completed in Taiwan in the past 5 years was conducted. A total of 198 healthy male volunteers were given a single dose of a 10 mg Adalat capsule as a reference drug after overnight fasting. Pharmacokinetic parameters derived from Adalat administration were calculated by non-compartmental analysis with the WinNonlin program. After oral administration of an immediate-release dosage form of a 10 mg nifedipine capsule to Taiwan residents, a skewed distribution with no clear evidence of bimodality of pharmacokinetic parameters was observed. The mean Cmax was 143.12+/-53.48 ng/ml, the mean AUC was 293.77+/-115.62 ng.h/ml, the mean T1/2 was 3.08+/-1.61 h, and the median value of Tmax was 0.61 h. Compared with other published studies, the Cmax and AUC of nifedipine after 10 mg administration were significantly higher in Taiwanese than in British and American subjects. However, the Cmax and AUC were similar to those of Indian and Mexican subjects. According to the antimode of AUC distribution of 22.5 ng.h/ml/mg proposed by Kleinbloesem, 69.7% of Taiwanese can be categorized as slow metabolizers. Based on the results in this study, the majority of Taiwanese show lower activity of nifedipine metabolism.