Influence of monte carlo variance with fluence smoothing in VMAT treatment planning with Monaco TPS.

INTRODUCTION: The study aimed to investigate the interplay between Monte Carlo Variance (MCV) and fluence smoothing factor (FSF) in volumetric modulated arc therapy treatment planning by using a sample set of complex treatment planning cases and a X‑ray Voxel Monte Carlo–based treatment planning system equipped with tools to tune fluence smoothness as well as MCV. MATERIALS AND METHODS: The dosimetric (dose to tumor volume, and organ at risk) and physical characteristic (treatment time, number of segments, and so on) of a set 45 treatment plans for all combinations of 1%, 3%, 5% MCV and 1, 3, 5 FSF were evaluated for five carcinoma esophagus cases under the study. RESULT: Increase in FSF reduce the treatment time. Variation of MCV and FSF gives a highest planning target volume (PTV), heart and lung dose variation of 3.6%, 12.8% and 4.3%, respectively. The heart dose variation was highest among all organs at risk. Highest variation of spinal cord dose was 0.6 Gy. CONCLUSION: Variation of MCV and FSF influences the organ at risk (OAR) doses significantly but not PTV coverage and dose homogeneity. Variation in FSF causes difference in dosimetric and physical parameters for the treatment plans but variation of MCV does not. MCV 3% or less do not improve the plan quality significantly (physical and clinical) compared with MCV greater than 3%. The use of MCV between 3% and 5% gives similar results as 1% with lesser calculation time. Minimally detected differences in plan quality suggest that the optimum FSF can be set between 3 and 5.

Analysis of common etiology between Takayasus Arteritis and Hyperthyroidism in a middle aged female in Eastern part of India

Takayasu’s arteritis is a chronic, progressive, granulomatous vasculitis involving large arteries especially aorta and its branches. Hyperthyroidism is a condition which involves excess synthesis and secretion of thyroid hormones by the thyroid gland. A 36 year old female patient presented at the General Medicine Outdoor of a tertiary-care hospital situated in the Eastern part of India with clinical features and laboratory reports suggestive of hyperthyroidism. There was also history of ischemic stroke 8 years back leading to right sided weakness in this patient. On careful physical examination left sided radial, brachial, femoral and dorsalis pedis arterial pulses were found to be impalpable. Digital subtraction angiography of aorta and its branches revealed narrowing of left common carotid and left subclavian artery suggestive of Takayasu’s arteritis. This existence of Takayasu’s arteritis and hyperthyroidism may not be just fortuitous. An underlying autoimmune mechanism might be a possible explanation.

Multicentric study of efficacy and safety of growth hormone use in growth hormone deficient children in India.

Growth Hormone being very expensive in India data on use of recombinant human growth hormone (rhGH) is scarce. The authors studied the effect and safety of one year of therapy with rhGH on growth velocity and predicted final height in Indian patients with growth hormone deficiency (GHD). A multicentric, prospective, open trial with rhGH was performed on 15 patients. Patients received rhGH in a dose of 0.7 IU (0.23 mg)/Kg/week. The mean pretreatment height was 111.2 cms {SD 12.4}, height velocity was 3.1 cms per year {1.2} and predicted height was 146.5 cms {10.4} at a mean age of 12.0 (2.8). At the end of therapy mean height was 123.4 {11.9}, height velocity was 12.1 cms per year {2.8} and the predicted height was 153.0 cm {9.4}. The increase in predicted height was thus 6.5 cm (4.2). The increment in height velocity with growth hormone therapy was statistically significant (p value= 0.001). The present study shows that children with growth hormone deficiency in India also benefit from therapy with rhGH even when treatment is started late as compared to the published Western data and there is a potential for increased final height.

Growth hormone in turner syndrome.

We assessed the effect of one year of therapy with recombinant Human Growth Hormone (rhGH) on growth velocity of 16 Indian girls with Turner Syndrome (TS) in a prospective, open trial. Patients received rhGH in a dose of 1 IU (0.3 mg)/kg/week. The mean pretreatment height was 117.1 cms (Z score minus 3.4), height velocity was 3.8 cm per year (Z score minus 2.4), and predicted height was 140 cm. At the end of therapy mean height was 123.9 (Z score minus 3.1), height velocity was 6.7 cm per year (Z score + 1.7), and the predicted height was 142.4 cm. The increment in height velocity with growth hormone therapy was statistically significant (P value = 0.001) and the mean increment in predicted height was 2.4 cm. Our study shows that girls with TS in India benefit from therapy with rhGH.