ASSESSING BODY DOSE RATE CONSTANT AND EFFECTIVE BODY ABSORPTION FACTOR IN TAIWANESE REFERENCE PHANTOMS.

The self-attenuation of a patient's body is an important factor in nuclear medicine for designing radiation shielding. Taiwanese reference man (TRM) and Taiwanese reference woman (TRW) were constructed to simulate the body dose rate constant and the effective body absorption factor for 18F-FDG, 131I-NaI and 99mTc-MIBI using the Monte Carlo technique. For TRM, the maximum body dose rate constants for 18F-FDG, 131I-NaI and 99mTc-MIBI were 1.26 × 10-1, 4.89 × 10-2 and 1.76 × 10-2 mSv-m2/GBq-h, respectively, at heights of 110, 110 and 100 cm. For TRW, the results were 1.23 × 10-1, 4.75 × 10-2 and 1.68 × 10-2 mSv-m2/GBq-h at heights of 100, 100 and 90 cm. The effective body absorption factors were 32.6, 36.7 and 46.2% for TRM and 34.2, 38.5 and 48.6% for TRW. Regional reference phantoms along with the derived body dose rate constant and effective body absorption factor should be used for determining regulatory secondary standards in nuclear medicine.

Patients with obstructive sleep apnea are at great risk of flavor disorders: a 15-year population-based cohort study.

OBJECTIVE: Obstructive sleep apnea (OSA) results from upper airway remodeling, which has been suggested to alter sensory and motor neuron function due to hypoxia or snore vibration. This study investigated whether OSA was associated with the risk of flavor disorder (FD). MATERIALS AND METHODS: Seven thousand and eight hundred sixty-five patients with OSA and 7865 propensity score-matched controls without OSA were enrolled between 1999 and 2013 through a nationwide cohort study. The propensity score matching was based on age, sex, comorbidities including hypertension, hyperlipidemia, chronic obstructive pulmonary disease (COPD), asthma, ankylosing spondylitis, and Charlson comorbidity index, and co-medications during the study period, including statins and angiotensin-converting enzyme (ACE) inhibitors. The adjusted hazard ratio (aHR) of incident FD following OSA was derived using a Cox proportional hazard model. A log-rank test was used to evaluate the time-dependent effect of OSA on FD. Age, sex, comorbidities, and co-medications were stratified to identify subgroups susceptible to OSA-associated FD. RESULTS: Patients with OSA were at a significantly great risk of FD (aHR = 1.91, 95% CI = 1.08-3.38), which was time-dependent (log-rank test p = 0.013). Likewise, patients with hyperlipidemia were at a significant great risk of FD (aHR = 2.99, 95% CI = 1.33-6.69). Subgroup analysis revealed that female patients with OSA were at higher risks of FD (aHR = 2.39, 95%CI = 1.05-5.47). CONCLUSIONS: Patients with OSA were at significantly great risk of incident FD during the 15-year follow-up period, especially in female patients with OSA. CLINICAL RELEVANCE: Timely interventions for OSA may prevent OSA-associated FD.

Use of a rich internet application solution to present medical images.

Browser with Rich Internet Application (RIA) Web pages could be a powerful user interface for handling sophisticated data and applications. Then the RIA solutions would be a potential method for viewing and manipulating the most data generated in clinical processes, which can accomplish the main functionalities as general picture archiving and communication system (PACS) viewing systems. The aim of this study is to apply the RIA technology to present medical images. Both Digital Imaging and Communications in Medicine (DICOM) and non-DICOM data can be handled by our RIA solutions. Some clinical data that are especially difficult to present using PACS viewing systems, such as ECG waveform, pathology virtual slide microscopic image, and radiotherapy plan, are as well demonstrated. Consequently, clinicians can use browser as a unique interface for acquiring all the clinical data located in different departments and information systems. And the data could be presented appropriately and processed freely by adopting the RIA technologies.

A conceptual design of rotating board technique for delivering total skin electron therapy.

PURPOSE: This study presents a novel technique in which a uniform radiation dose to the whole body, soles, and scalp vertex can be achieved in one electron beam treatment fraction. METHODS: The patient was treated at a machine with a home-made rotating board. The patients were treated in two groups in the prone and supine positions by leaning onto an inner rotational board in the prone and supine positions. Each group can further be separated into two subgroups using tilting and rotational positions for treatment. RESULTS: One of the beams was directed 15.5 degrees upward and 15.5 degrees downward from the horizontal axis to provide a field size of as large as 200 cm in height and 140 cm in width. An incline angle of 31.5 degrees anteriorly (forward) or posteriorly (backward) of the outer frame at an angle rotated 60 degrees clockwise or counterclockwise to the inner frame was found to be most appropriate. The output for the rotating board total skin electron therapy (RB-TSET) was 0.046 cGy/MU at ISD of 350 cm. The beam characteristics of the RB-TSET depth dose curves were R50 = 2.48 cm, dmax = 0.7 cm, E0 = 5.78 MeV, and Rp = 3.4 cm. CONCLUSIONS: The RB-TSET technique presented in this study is able to deliver a uniform radiation dose to the patient's skin surface, the scalp vertex, and soles of the feet all at one time, eliminating the trouble of having to further irradiate these two regions separately when using the Stanford six field technique.