[Treatment with ranibizumab for choroidal neovascularization secondary to a pseudoxanthoma elasticum: Results of the French observational study PiXEL]. / Traitement par ranibizumab des néovascularisations choroïdiennes secondaires à un pseudoxanthome élastique : résultats de l'étude observationnelle française PiXEL.

INTRODUCTION: Pseudoxanthoma elasticum (PXE), a rare hereditary connective tissue disorder, may be complicated by angioid streaks (AS) and choroidal neovascularization (CNV), which may lead to irreversible loss of visual acuity (VA). Here we describe the safety and efficacy of ranibizumab in patients with CNV secondary to PXE. METHODS: A multicenter (n=23), observational study of a retrospective/prospective cohort, performed under real world conditions in France in all patients with CNV secondary to PXE who received at least one ranibizumab injection as of October 2011. The study objectives were to describe the mean annual number and reason for ranibizumab injections since initiation, evolution of best-corrected visual acuity (BCVA by Early Treatment Diabetic Retinopathy Study [ETDRS] letters), and safety. RESULTS: Patients (n=72; 98 eyes) had a mean age of 59.6±8.3years and consisted of 54.2% men. The criterion for retreatment was based mainly on loss of VA, progression of CNV and angiographic leakage. CNV was primarily subfoveal or juxtafoveal (73.4%), and the initial mean VA was 64.6 ETDRS letters. On average, visual acuity of all eyes analyzed was relatively stable during the 2-year follow-up (62.3 letters vs 64.6 letters at the first injection), and 88.6% of eyes maintained VA between -15 and +15 letters or gained over 15 letters. No deaths or new intolerances were described. CONCLUSIONS: These results showed that ranibizumab was able to maintain stable VA in clinical practice for at least 2years in patients with CNV secondary to PXE, and to significantly reduce the frequency of neovascularization relapses, with a limited number of injections. The treatment was well tolerated by the patients.

Predicting the biochemical methane potential of wide range of organic substrates by near infrared spectroscopy.

The use of near infrared spectroscopy (NIRS) as an alternative method to predict the biochemical methane potential (BMP) of a broad range of organic substrates was investigated. A total of 296 samples including most of the substrates treated by anaerobic co-digestion were used for NIRS calibration and validation. The NIRS predictions of the BMP values were satisfactory (Root Mean Square Error = 40 ml CH(4) g(-1) VS(fed); r(2) = 0.85). The integration of the entire substrate diversity in the model remained nevertheless difficult due to the specific organic matter properties of stabilised substrates and the high level of uncertainty of the BMP values. The elaboration of a model restricted to "fresh" substrates allows the practical use of the NIR technique to design and operate anaerobic co-digestion plants. The addition of more samples in the dataset in order to perform local calibrations would probably make the elaboration of a global NIR-model possible.