Success Rates and their Related Factors in Patients Receiving Radioiodine (I-131) Treatment for Hyperthyroidism.

Background and Objective: The success rate of I-131 therapy for hyperthyroidism is dependent on several factors. The aim of the present study was to evaluate the success rates, and the factors which affected them, in patients with hyperthyroidism at Rajavithi Hospital who received I-131 therapy with doses based on thyroid gland weight (gram), clinical findings, and 3-hour radioiodine uptake (3-hr RAIU). Material and Method: A retrospective study was performed of 305 hyperthyroid patients who received initial I-131 therapy at the Nuclear Medicine Department of Rajavithi Hospital, Bangkok between January 2010 and December 2014. Baseline characteristics, including thyroid gland weight (g), 3-hr RAIU, I-131 dose and all patient outcomes were reviewed. Success after initial I-131 therapy was defined as evidence of stable euthyroid or hypothyroid within 1 yr. Results: A total of 305 hyperthyroid patients were enrolled. The mean (SD) age, gland weight, 3-hr RAIU, and I-131 dose were 44.17 (15.14) years, 51.19 (31.95) grams, 50.62 (24.36) and 14.40 (5.71) mCi. respectively. The success rate within 12 months was 66.3 %, and the factors associated with success were I-131 dose (p = 0.014), gland size (p = 0.044), 3-hr RAIU (p = 0.02) and underlying cardiovascular disease (p = 0.014). Conclusion: The mean (SD) I-131 treatment dose was 14.4 (5.71) mCi., and the success rate within 1 year was 66.3%. I-131 therapy is an effective treatment for hyperthyroidism, and its rate of success rate depends on both patient factors and I-131 treatment dose.

Gestational Gigantomastia: A Case Report.

Gestational gigantomastia is a rare disorder characterized by rapidly progressive hypertrophy of the breast tissue during pregnancy. Its prevalence is approximately 1:100,000, and although the etiology of this condition remains unclear, it may be related to hormonal change. This study reports the case of a 39-year-old pregnant woman at 22 weeks of gestation with massive enlargement of bilateral breasts (gigantomastia) and presents the sonographic findings of this rare condition which shows different parenchymal patterns from those of normal breasts and is uncommonly seen.

Radioiodine (1-131) Dose for the Treatment of Hyperthyroidism in Rajavithi Hospital.

BACKGROUND: The main cause of hyperthyroidism is diffuse toxic goiter (Graves' disease), and the treatment of choice after medical therapy failure is radioiodine (I-131). There are two common methods of determining the optimal I-131 dose: calculated dose or fixed dose. The calculated dose method is based on the following formula: 75-200 microcuri/gram of thyroid gland divided by the percentage of radioiodine uptake at 24 hours (24-hour RAIU). As this is quite complex, some centers use fixed doses, such as 5, 10 or 15 mCi because it is simpler. At Rajavithi Hospital, the applied dose of I-131 is determined based on the thyroid gland weight assessed by palpation and other clinical factors. OBJECTIVE: To study the mean I-131 dose for the initial treatment of hyperthyroidism in Rajavithi Hospital, to find the clinical factors that correlate with I-131 treatment dose, and to devise a formula to predict the optimal I-131 treatment dose. MATERIAL AND METHOD: This was a retrospective study of 510 patients with a diagnosis of hyperthyroidism who received initial I-131 treatment at the Department of Nuclear Medicine in Rajavithi Hospital between January 2014 and June 2015. Baseline characteristics including age, sex, age at diagnosis, duration of antithyroid drug (ATD) therapy, gland weight (g), 3-hour RAIU and I-131 treatment dose were reviewed from medical records. RESULTS: The mean age ± SD was 41.93 ± 14.11 years (range 14-81 years), and the male to female ratio was 4.1:1. The mean duration of ATD therapy was 3.54 ± 4.02 years (min-max, 0.8-40.6 years). The mean gland weight was 54.35 ± 32.95 grams, and the mean 3-hour RAIU was 55.5 ± 23.69%. The mean I-131 treatment dose was 14.84 ± 5.71 mCi (min-max, 7-30 mCi). There was no significant correlation between dose and age, age at diagnosis, duration of A TD therapy or 3-hour RAIU. The study showed a significant correlation between I-131 dose and gland size, r = 0.938 (p < 0.001), and the regression relationship equation was: 1-131 dose = 0.235 gland size, r = 0.938. CONCLUSION: I-131 is the treatment of choice for hyperthyroidism after medical therapy failure, and there are various techniques for determining the optimal dose. At Rajavithi Hospital, the I-131 dose (mean = 14.84 ± 5.71 mCi) is estimated based on the gland weight by palpation and other additional clinical factors. The present study provided a practical formula which is simple and practical for use in determining the I-131 dose for the treatment of hyperthyroidism: Dose of I-131 (mCi) = 0.235 x gland size (g).

Normal Solid Gastric Emptying Values Measured by Scintigraphy Using Asian-style Meal:A Multicenter Study in Healthy Volunteers.

BACKGROUND/AIMS: To report gastric emptying scintigraphy, normal values should be established for a specific protocol. The aim of this study was to provide normal gastric emptying values and determine factors affecting gastric emptying using Asian rice-based meal in healthy volunteers. METHODS: One hundred and ninety-two healthy volunteers were included at 7 tertiary care centers across Thailand. Gastric emptying scintigraphy was acquired in 45 degree left anterior oblique view immediately after ingestion of a 267 kcal steamed-rice with technetium-99m labeled-microwaved egg meal with 100 mL water for up to 4 hours. RESULTS: One hundred and eighty-nine volunteers (99 females, age 43 ± 14 years) completed the study. The medians (5-95th percentiles) of lag time, gastric emptying half time (GE T1/2) and percent gastric retentions at 2 and 4 hours for all volunteers were 18.6 (0.5-39.1) minutes, 68.7 (45.1-107.8) minutes, 16.3% (2.7-49.8%) and 1.1% (0.2-8.8%), respectively. Female volunteers had significantly slower gastric emptying compared to male (GE T1/2, 74 [48-115] minutes vs. 63 (41-96) minutes; P < 0.05). Female volunteers who were in luteal phase of menstrual cycle had significantly slower gastric emptying compared to those in follicular phase or menopausal status (GE T1/2, 85 [66-102] mintes vs. 69 [50-120] minutes or 72 [47-109] minutes, P < 0.05). All of smoking volunteers were male. Smoker male volunteers had significantly faster gastric emptying compared to non-smoker males (GE T1/2, 56 [44-80] minutes vs. 67 [44-100] minutes, P < 0.05). Age, body mass index and alcohol consumption habits did not affect gastric emptying values. CONCLUSIONS: A steamed-rice with microwaved egg meal was well tolerated by healthy volunteers. Gender, menstrual status and smoking status were found to affect solid gastric emptying.