Critical Appraisal of Paediatric Embryonal Cancers Treated with Image-guided Intensity-modulated Proton Therapy.

AIM: To carry out a comprehensive critical appraisal of image-guided intensity-modulated proton therapy practice for craniospinal irradiation (CSI). MATERIALS AND METHODS: An image-guided intensity-modulated proton therapy database of 45 consecutive paediatric patients with central nervous system embryonal malignancies treated between January 2019 and April 2022 were critically appraised for demography, diagnosis, treatment planning strategy and treatment delivery accuracy. RESULTS: Most patients (median age: 7.5 years; male:female ratio: 34:11) had medulloblastoma (56%), followed by recurrent ependymoma (19%), pinealoblastoma (5%), germ cell (5%) and others (15%). The dose to the planning target volume-craniospinal (PTV-CS; length 39.06-79.59 cm) varied from 21 to 35 GyRBE, whereas the combined median dose to craniospinal and boost was 54 GyRBE. In all patients, the 95% isodose line covered the cribriform plate completely and optic nerves mostly, with a median V95% of 100% and 82.96%, keeping Dmax to the lens <3.9 GyRBE. In skeletally immature patients (88.38%), the anterior vertebral body was completely covered in 18.18% and underdosed in 70.15% of the cases, resulting in a median Dmean of 10.11 GyRBE to the oesophagus. Lateral spine coverage was maintained on the edges of the vertebral body in 52.2%, whereas it extended beyond in 48.8%. The median V98% for clinical target volumes and V95% for PTVs of the brain, spine and craniospinal were >97%, with excellent conformity (0.89) and homogeneity (0.07) indices for PTV-CS. All neurological organs at risk received a median Dmax ranging from 36 to 44 GyRBE from the combined CSI and boost regimens. Analysis of patient-specific quality assurance results revealed that 545 (97.67%) planar dosage verification had gamma (3% at 3 mm) values >95%. The online patient set-up verification showed translational and rotational deviation within 2 mm and 0.5° in 88-94% and 97% of the cases. Systematic and random error were within 0.90 mm and 1.71 mm in translation and 0.1° and 0.2° in rotation. CONCLUSION: A change in practice pattern was observed. The findings from our comprehensive critical appraisal add to the growing library of CSI practice and may serve as a reference for inter-institutional comparison.

Comparative evaluation of a novel fluorescent marker and environmental surface cultures to assess the efficacy of environmental cleaning practices at a tertiary care hospital.

BACKGROUND: Cleaning high-touch surfaces serves as a crucial step towards controlling the transmission of multidrug-resistant pathogens in hospital environments. The process can be made most effective if scientifically monitored using a simple, feasible and reliable technique, especially in resource-poor settings. AIM: To identify a novel florescent marker (FM) comparable to the already existing commercial FM systems and to assess its efficacy in evaluating cleaning of high-touch surfaces in a hospital environment. METHODS: A liquid detergent used for washing purposes was identified as a novel FM. Pre- and post-cleaning sampling were performed from 250 high-touch surfaces in different patient-care areas using this marker and aerobic colony counts. Concordance between the two methods was assessed and compared by Cohen's kappa coefficient. The sensitivity, specificity, positive predictive and negative predictive values for the new FM method were calculated against the microbiological method. FINDINGS: A good correlation (κ = 0.60) with overall concordance of 79.6% was observed between the two methods. The sensitivity, specificity, positive predictive value and negative predictive value of the FM were 79.58% (95% confidence interval (CI): 72-85.85%), 79.63% (95% CI: 70.79-86.78), 83.70% (95% CI: 76.38-89.50) and 74.78% (95% CI: 65.83-82.38), respectively. CONCLUSIONS: The FM used in the present study proved to be a simple and cost-effective alternative to commercially available FMs for assessing environmental cleaning practices on a daily basis in resource-poor settings. Additional studies making direct comparisons of the FM used here with the established FMs are warranted before it can be generalized for use.

Experimental studies (in vitro) on polyene macrolide antibiotics with special reference to hamycin against Malassezia ovale.

Hamycin activity (in vitro) against Malassezia ovale was studied and compared with old and newly discovered polyene antifungal antibiotics. Hamycin showed a marked anti-M. ovale activity which was enhanced in the presence of divalent cations like Cu++ and Zn++. Furthermore, the absorption of hamycin onto the cell membrane or cell surface of M. ovale was also increased in the presence of divalent cations. It is suggested that hamycin alone or along with metal ions, specifically Cu++ may be useful clinically in the treatment of dandruff or seborrheic dermatitis.