INTRODUCTIONWith the global outbreak of Zika virus and its association with microcephaly, an up-to-date fetal head circumference (HC) nomogram is crucial to offer a reference standard in order to make an accurate diagnosis. This study was conducted to revise the local fetal HC nomogram.

MATERIALS AND METHODSIn this retrospective study, ultrasound data was used for construction of the fetal HC nomogram from a total of 6155 pregnancies in the ethnic Chinese population with low risk profile at KK Women's and Children's Hospital over a 10-year period. Regression model was fitted to calculate the mean and standard deviation of HC at each gestational age (GA). Comparison of HC between ethnic groups (no significant differences) and genders were made. The revised chart was compared with another commonly used reference chart (Hadlock). In an independent test population, different reference charts were used to estimate number of cases with microcephaly.

RESULTSA statistically significant difference of HC between the genders was observed across all gestational ages. Gender-specific reference charts and equation were computed. Our revised fetal HC chart showed a different distribution from the Hadlock chart. Compared with the gender-specific charts, the Hadlock HC chart would significantly under-report microcephaly cases in male fetuses, and tend to over-report in female fetuses.

CONCLUSIONThis study provides a new set of gender-specific fetal HC charts in the Singaporean population for antenatal ultrasound surveillance of microcephaly.

INTRODUCTION: Cast immobilisation remains the mainstay of treatment for various fractures in paediatric patients, yet patients commonly complain of skin irritation and discomfort. This study aimed to perform a qualitative and quantitative evaluation of the effects of cast immobilisation on the skin of children and adolescents. MATERIALS AND METHODS: Patients aged 6-17 years of age with a fracture treated in a fiberglass short-arm or short-leg cast were recruited. Transepidermal water loss (TEWL), stratum corneum (SC) hydration, hair density and presence of any skin signs were assessed before and after cast. Patients were required to complete a weekly questionnaire to rate itch, malodour, warmth, and dampness of the skin under the cast. RESULTS: A total of 60 subjects completed the study. Thirty-six patients received a short-arm cast; 24 received a short-leg cast. Upon cast removal, TEWL was significantly increased on the volar surface of the arms and legs ( <0.05), and the dorsal surface of the arm ( <0.05). Likewise, SC hydration was significantly increased at most sites ( <0.05), except the volar surface of the leg ( = 0.513). There was no change in hair density. Throughout the duration of casting, there was an increase in itch and malodour scores. CONCLUSION Moderate but significant changes in TEWL, SC hydration and subjective symptoms were observed during the duration of cast immobilisation, demonstrating that cast immobilisation for up to 4 weeks exerts moderate adverse impact on patients' skin. Further studies to explore the use of better materials for cast immobilisation to improve skin barrier function and overall patient satisfaction are warranted.