Comparison of refractive outcomes using immersion ultrasound biometry and IOLMaster biometry

Background:  The IOLMaster determines axial length using partial coherence interferometry. This study was designed to compare the refractive outcomes of patients who had been measured preoperatively by both immersion ultrasound and IOLMaster biometry.
Methods:  Patients were recruited from those who had undergone cataract surgery during the preceding 12 months by one surgeon at The Queen Elizabeth Hospital (55 eyes from 55 patients). Each patient underwent measurement of axial length by immersion ultrasound and the IOLMaster. Target refraction was determined using an SRK-T formula and the amount that this differed postoperative refraction was calculated for immersion ultrasound and the IOLMaster. These results were then compared.
Results:  Eyes measured longer by the IOLMaster method compared with immersion ultrasound (23.37 ± 0.87 vs. 23.25 ± 0.90 mm, t  = 4.83; P  < 0.0001). However anterior chamber depth was the similar. Postoperatively, final refractive outcome was 0.01 ± 0.63 dioptres (D) more hypermetropic than the target refraction when using the IOLMaster compared with 0.25 ± 0.73 D more myopic when using immersion ultrasound ( t  = 3.83; P  < 0.0001). Seventy-five per cent of patients were within 0.5 D of target refraction and 93% were within 1.0 D when the IOLMaster was used, compared with 49% and 85% within 0.5 and 1.0 D respectively when using immersion ultrasound (χ² = 8.34; P  = 0.04).
Conclusions:  Biometry performed using the IOLMaster produces a more predictable refractive outcome than immersion ultrasound, with patients' spherical equivalent more likely to be closer to their target refraction.     

Awareness of and compliance with recommended dietary supplement among age-related macular degeneration patients

BACKGROUND: The age-related eye disease study suggested that taking zinc and anti-oxidants supplements could reduce the progression of age-related macular degeneration (AMD). In Australia, the available supplement is Macu-Vision. The study aimed to assess the awareness of and compliance with taking this supplement and the public health implication. METHODS: The fundus photograph database of patients aged 55 years and older at the ophthalmology department of a public teaching hospital in Adelaide, Australia was reviewed. In total, 125 patients with category 3 and 4 AMD were identified. A total of 100 patients participated in this cross-sectional study. RESULTS: In total, 53% of participants were aware of the availability of the formulae available in Australia, 38% were taking the supplement and only 1% were taking the correct dose. Of those taking the supplement 95% (36/38) were taking half the recommended dosage. Among those who were aware of the supplement but not taking it, cost was the most common reason (31%). Another 31% were not taking it because of actual side-effects experienced, fear of potential side-effect and/or fear of interaction with other medications. There was no predictive factor for failing to take the formulae available in Australia among age, sex, smoking status, living arrangement and category of AMD. CONCLUSIONS: Clinicians need to emphasize that the recommended dosage is twice that on the supplement label. If the trend demonstrated here of underutilizing the formulae available in Australia among public hospital patients continues, it is unlikely to have any major public health impact in similar settings in Australia.     

“I May Not Say We Really Have a Method,It Is Gambling Work”: Knowledge and Acceptability of Safer Conception Methods Among Providers and HIV Clients in Uganda

In this qualitative study, researchers assessed knowledge, acceptability, and feasibility of safer conception methods (SCM; timed unprotected intercourse [TUI], manual self-insemination, and sperm washing) among various health care providers (n = 33) and 48 HIV clients with recent or current childbearing intentions in Uganda. While several clients and providers had heard of SCM (especially TUI), few fully understood how to use the methods. All provider types expressed a desire to incorporate SCM into their practice; however, this will require training and counseling protocols, sensitization to overcome cultural norms that pose obstacles to these methods, and partner engagement (particularly by men) in safer conception counseling.     

FIRO-BC normative and psychometric data on 9- through 13-year-old children

Study concerned principally with the need to provide normative and psychometric data for the FIRO-BC questionnaire. Reported are the means, standard deviations, test-retest reliability coefficients, and interscale correlation coefficients. Data are reported separately for boys and girls (N = 282). In addition, techniques of FIRO-BC data analyses are reviewed and alternatives are discussed.     

A semimechanistic and mechanistic population PK-PD model for biomarker response to ibandronate, a new bisphosphonate for the treatment of osteoporosis

AIMS: Ibandronate, a highly potent nitrogen-containing bisphosphonate, is the subject of an ongoing clinical development programme that aims to maximize the potential of simplified, less frequent oral and intravenous (i.v.) administration in osteoporosis. A modelling and simulation project was undertaken to characterize further the clinical pharmacology of ibandronate and identify convenient intermittent oral and i.v. regimens for clinical evaluation. METHODS AND RESULTS: Using selected data from clinical studies involving 174 women with postmenopausal osteoporosis (PMO), a classical multicompartmental pharmacokinetic-pharmacodynamic (PK-PD) model was developed that accurately described the PK of i.v. ibandronate in plasma and urine and urinary excretion of the C-telopeptide of the alpha chain of type I collagen (uCTX), a sensitive biomarker of PD response to ibandronate. To reduce processing times, the classical PK-PD model was simplified using a "kinetics of drug action" or kinetic (K)-PD model (i.e. a dose-response model as opposed to a dose-concentration-response model). The performance of the K-PD model was evaluated by fitting data simulated with the PK-PD model under various dosing regimens. The simplified model produced a virtually indistinguishable fit of the data from that of the PK-PD model. The K-PD model was extended to consider the influence of supplemental therapy (calcium with or without vitamin D) on the PD response and validated by retrospectively simulating the uCTX response in a prior Phase III and Phase II/III study of i.v. ibandronate, given once every 3 months, in 3380 women with PMO. The observed median uCTX responses at the scheduled assessment points in the completed studies were within the distribution of the simulated responses. The K-PD model for i.v. ibandronate was extended further to allow simultaneous fitting of uCTX responses after i.v. and oral administration in 676 postmenopausal women with osteoporosis, and validated by retrospectively simulating the data observed in a Phase I study of oral daily ibandronate in 180 women with PMO. The K-PD model adequately described the uCTX response after oral dosing. CONCLUSIONS: This validated K-PD model is currently being used to evaluate a range of novel intermittent oral and i.v. ibandronate regimens in an ongoing clinical development programme.