Quality controls for two heel bone ultrasounds used in the Swiss Evaluation of the Methods of Measurement of Osteoporotic Fracture Risk Study

Because of the important morbidity and mortality associated with osteoporosis, it is essential to detect subjects at risk by screening methods, such as bone quantitative ultrasounds (QUSs). Several studies showed that QUS could predict fractures. None, however, compared prospectively different QUS devices, and few data of quality controls (QCs) have been published. The Swiss Evaluation of the Methods of Measurement of Osteoporotic Fracture Risk is a prospective multicenter study that compared three QUSs for the assessment of hip fracture risk in a population of 7609 women age >/=70 yr. Because the inclusion phase lasted 20 mo, and because 10 centers participated in this study, QC became a major issue. We therefore developed a QC procedure to assess the stability and precision of the devices, and for their cross-calibration. Our study focuses on the two heel QUSs. The water bath system (Achilles+) had a higher precision than the dry system (Sahara). The QC results were highly dependent on temperature. QUS stability was acceptable, but Sahara must be calibrated regularly. A sufficient homogeneity among all the Sahara devices could be demonstrated, whereas significant differences were found among the Achilles+ devices. For speed of sound, 52% of the differences among the Achilles+ was explained by the water s temperature. However, for broadband ultrasound attenuation, a maximal difference of 23% persisted after adjustment for temperature. Because such differences could influence measurements in vivo, it is crucial to develop standardized phantoms to be used in prospective multicenter studies.

Quality control for retinal OCT in multiple sclerosis: validation of the OSCAR-IB criteria.

BACKGROUND Retinal optical coherence tomography (OCT) permits quantification of retinal layer atrophy relevant to assessment of neurodegeneration in multiple sclerosis (MS). Measurement artefacts may limit the use of OCT to MS research. OBJECTIVE An expert task force convened with the aim to provide guidance on the use of validated quality control (QC) criteria for the use of OCT in MS research and clinical trials. METHODS A prospective multi-centre (n = 13) study. Peripapillary ring scan QC rating of an OCT training set (n = 50) was followed by a test set (n = 50). Inter-rater agreement was calculated using kappa statistics. Results were discussed at a round table after the assessment had taken place. RESULTS The inter-rater QC agreement was substantial (kappa = 0.7). Disagreement was found highest for judging signal strength (kappa = 0.40). Future steps to resolve these issues were discussed. CONCLUSION Substantial agreement for QC assessment was achieved with aid of the OSCAR-IB criteria. The task force has developed a website for free online training and QC certification. The criteria may prove useful for future research and trials in MS using OCT as a secondary outcome measure in a multi-centre setting.

TREAT-AND-EXTEND REGIMENS WITH ANTI-VEGF AGENTS IN RETINAL DISEASES: A Literature Review and Consensus Recommendations

PURPOSE A review of treat-and-extend regimens (TERs) with intravitreal anti-vascular endothelial growth factor agents in retinal diseases. METHODS There is a lack of consensus on the definition and optimal application of TER in clinical practice. This article describes the supporting evidence and subsequent development of a generic algorithm for TER dosing with anti-vascular endothelial growth factor agents, considering factors such as criteria for extension. RESULTS A TER algorithm was developed; TER is defined as an individualized proactive dosing regimen usually initiated by monthly injections until a maximal clinical response is observed (frequently determined by optical coherence tomography), followed by increasing intervals between injections (and evaluations) depending on disease activity. The TER regimen has emerged as an effective approach to tailoring the dosing regimen and for reducing treatment burden (visits and injections) compared with fixed monthly dosing or monthly visits with optical coherence tomography-guided regimens (as-needed or pro re nata). It is also considered a suitable approach in many retinal diseases managed with intravitreal anti-vascular endothelial growth factor therapy, given that all eyes differ in the need for repeat injections. CONCLUSION It is hoped that this practical review and TER algorithm will be of benefit to health care professionals interested in the management of retinal diseases.