高津 安男

OBJECTIVES: Insulin-derived amyloidosis (IDA) reduces insulin absorption, increasing the risk of poor glycemic control; however, early detection remains challenging. Although ultrasound can identify IDA, the effectiveness of portable pocket-sized devices has not been evaluated. This study was performed to evaluate the detectability of findings suggestive of IDA using a pocket-sized ultrasound device on the abdominal region, the most common site for stable insulin absorption in patients with diabetes mellitus. METHODS: This cross-sectional observational study was conducted in the diabetes ward of a university hospital between July and December 2024. The participants were inpatients with diabetes who had been receiving insulin injections for more than 1 month. Findings suggestive of IDA were assessed through visual inspection and palpation, magnetic resonance imaging (MRI), high-performance ultrasonography, and a pocket-sized ultrasound device. The concordance rate between the pocket-sized ultrasound device and other assessment methods was calculated. RESULTS: Of the 20 participants enrolled, 5 met the exclusion criteria; thus, data from 15 participants were included in the final analysis. Findings suggestive of IDA were identified in nine patients (60.0%) by visual inspection and palpation and in eight patients (53.3%) by the pocket-sized ultrasound device, high-performance ultrasound, and MRI. The concordance rate among the pocket-sized ultrasound device, high-performance ultrasound, and MRI was 100%, while the concordance rate between visual inspection with palpation and the pocket-sized ultrasound device was 80%. CONCLUSIONS: These findings suggest that a pocket-sized ultrasound device has the potential to detect findings suggestive of IDA and may be suitable for use in clinical practice.

Background Relaxation time of female reproductive organs affects the tissue contrast of magnetic resonance image (MRI), and is used for quantitative analysis. Purpose To evaluate the relaxation times of normal female reproductive organs in the luteal phase of the menstrual cycle. Material and Methods On a 1.5-T MRI, relaxation times were measured in pelvic tissues (endometrium, junctional zone, myometrium, follicle, and stroma) of 32 female healthy volunteers (33.5 ± 6.8 years). The Look–Locker sequence was used to measure T1 relaxation times. Furthermore, a multiple spin-echo method with 32 different echo times was used to measure T2 relaxation times. The images were obtained in the luteal phase of each volunteer’s menstrual cycle. Results The measured relaxation times (means ± standard deviations) were as follows: endometrium (T1, 1703 ± 147 ms; T2, 214 ± 35 ms), junctional zone (T1, 1168 ± 63 ms; T2, 72 ± 12 ms), myometrium (T1, 1314 ± 103 ms; T2, 138 ± 20 ms), follicle (T1, 2267 ± 249 ms; T2, 603 ± 68 ms), and stroma (T1, 1481 ± 129 ms; T2, 126 ± 29 ms). Conclusion Reliable MRI measurements of T1 and T2 relaxation times of normal female reproductive organs in the luteal phase of the menstrual cycle are useful as references to recognize the normal value.