RESUMO
BACKGROUND AND OBJECTIVE: Head injury is the leading cause of fatalities and disabilities in children. Characterizing the variation in cranial size/shape and thickness during growth is important for developing finite element models of child heads and evaluating head injury risk at different ages. However, the quantitative morphological features of the cranial vault (size/shape and non-uniform thickness distribution) have not been accounted for in children aged between 3 and 10 years old (YO). METHODS: Geometrically equivalent discrete points were identified on 42 head CT scans of 3-10 YO children by separation, curve dividing, and point fitting. Based on discrete points, the principal component analysis and regression (PCA&R) method was used to develop a statistical model of the cranial vault as a function of age and head circumference. RESULTS: The ontogeny of three-dimensional cranial morphology and non-uniform thickness from 3 to 10 years of age was quantified and cranial vault morphologies for 3-10 YO children were generated in 1 year intervals. CONCLUSIONS: The automatic method, the procedure of identifying discrete points from CT scans, and the developed quantitative cranial vault model are reliable and accurate.
Assuntos
Modelos Estatísticos , Crânio , Cefalometria , Criança , Pré-Escolar , China , Cabeça , Humanos , Lactente , Crânio/diagnóstico por imagemRESUMO
PURPOSE: In this randomized phase II study, we evaluated the efficacy of semustine added to CEOP regimen as induction chemotherapy in patients with stage I(E)/II(E) extranodal NK/T-cell lymphoma, nasal type in the upper aerodigestive tract. PATIENTS AND METHODS: Seventy-five eligible patients were randomized to receive either CEOP or CEOP plus semustine followed by involved-field radiotherapy. RESULTS: The overall response rate of induction chemotherapy was 57.9% in CEOP arm compared with 62.2% in CEOP plus semustine arm (P=0.71). With a median follow-up of 30.1 months, 2-year overall survival was 73.3% and 62.2%, respectively (P=0.37). Toxicities in both arms were comparable and manageable. Through univariate and multivariate analysis, PS of 2, Stage II(E) and elevated LDH level were identified to be adverse prognostic factors. A new prognostic index categorized three groups of patients (low risk, no adverse factors; intermediate risk, one factor; and high risk, 2 or 3 factors) with highly significant difference of prognosis. Two-year overall survival was 87.5%, 60.6% and 30%, respectively (P=0.0002). CONCLUSIONS: The addition of semustine to CEOP regimen was not associated with improved efficacy. More effective treatment needs to be explored in patients with intermediate or high risk.