Evaluation of the ear ossicles with photon-counting detector CT

Recently, computed tomography with photon-counting detector (PCD-CT) has been developed to enable high-resolution imaging at a lower radiation dose. PCD-CT employs a photon-counting detector that can measure the number of incident X-ray photons and their energy. The newly released PCD-CT (NAEOTOM Alpha, Siemens Healthineers, Forchheim, Germany) has been in clinical use at our institution since December 2022. The PCD-CT offers several advantages over current state-of-the-art energy-integrating detector CT (EID-CT). The PCD-CT does not require septa to create a detector channel, while EID-CT does. Therefore, downsizing the anode to achieve higher resolution does not affect the dose efficiency of the PCD-CT. CT is an indispensable modality for evaluating ear ossicles. The ear ossicles and joints are clearly depicted by PCD-CT. In particular, the anterior and posterior legs of the stapes, which are sometimes unclear on conventional CT scans, can be clearly visualized. We present cases of congenital anomalies of the ossicular chain, ossicular chain dislocation, tympanosclerosis, and cholesteatoma in which PCD-CT was useful. This short article reports the usefulness of PCD-CT in the 3D visualization of the ear ossicles

Investigation of abdominal artery delineation by photon-counting detector CT

The version of record of this article, first published in La Radiologia Medica, is available online at Publisher’s website: https://doi.org/10.1007/s11547-024-01858-z.Objectives: To evaluate the ability of 50-keV virtual monoenergetic images (VMI) to depict abdominal arteries in abdominal CT angiography (CTA) compared with 70-keV VMI with photon-counting detector CT (PCD-CT). Methods: Fifty consecutive patients who underwent multiphase abdominal scans between March and April 2023 were included. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were quantitatively assessed for the abdominal aorta (AA), celiac artery (CeA), superior mesenteric artery (SMA), renal artery (RA), and right hepatic artery (RHA) at both 50- and 70-keV VMI. In addition, 3D images from CTA were analyzed to measure arterial lengths and evaluate the visualization of distal branches. Results: Significantly higher SNR and CNR were observed at 50-keV compared to 70-keV VMI for all arteries: AA (36.54 and 48.28 vs. 25.70 and 28.46), CeA (22.39 and 48.38 vs. 19.09 and 29.15), SMA (23.34 and 49.34 vs. 19.67 and 29.71), RA (22.88 and 48.84 vs. 20.15 and 29.41), and RHA (14.38 and 44.41 vs. 13.45 and 27.18), all p < 0.05. Arterial lengths were also significantly longer at 50-keV: RHA (192.6 vs. 180.3 mm), SMA (230.9 vs. 216.5 mm), and RA (95.9 vs. 92.0 mm), all p < 0.001. Conclusion: In abdominal CTA with PCD-CT, 50-keV VMI demonstrated superior quantitative image quality compared to 70-keV VMI. In addition, 50-keV VMI 3D CTA allowed better visualization of abdominal artery branches, highlighting its potential clinical advantage for improved imaging and detailed assessment of abdominal arteries

Relationships between Composition of Major Fatty Acids and Fat Distribution and Insulin Resistance in Japanese

Objective. The aim of this study was to evaluate the relationships between the composition of free fatty acids (FFAs) and metabolic parameters, including body fat distribution, in Japanese. Methods. The study subjects were 111 Japanese patients (54 males, 57 females). Metabolic parameters and visceral and subcutaneous fat areas as determined by CT scanning at the umbilical level were measured. Glucose tolerance test (GTT) was performed by administering 75 g glucose orally. Results. The percentage of linoleic acid (C18:2), the greatest constituent among FFAs, was negatively correlated with visceral fat area (r = −0 411, p &lt; 0 0001), fasting glucose (r = −0 330, p &lt; 0 0001), HbA1c (r = −0 231, p = 0 0146), and systolic blood pressure (r = −0 224, p = 0 0184). Linoleic acid percentage was also significantly negatively correlated with HOMA-IR (r = −0 416, p &lt; 0 0001) by simple correlation. Based on the findings of OGTT, the 111 subjects were classified into three groups: 33 with normal glucose tolerance, 71 with impaired glucose tolerance (IGT), and 7 diabetic subjects. The percentage of serum linoleic acid in diabetic subjects was significantly lower than that in normal subjects. Conclusion. We conclude that serum linoleic acid level is negatively correlated with the accumulation of visceral fat in relation to a reduction of insulin resistance in Japanese subjects

Plasma Antimicrobial Peptide LL-37 Level Is Inversely Associated with HDL Cholesterol Level in Patients with Type 2 Diabetes Mellitus

Introduction. Relation between atherosclerosis and innate immunity has attracted attention. As the antimicrobial peptide, LL-37, could have an important role in atherosclerosis, we supposed that there could be a meaningful association of plasma LL-37 level with risk factors for cardiovascular disease in subjects with type 2 diabetes mellitus. Materials and Methods. We evaluated plasma LL-37 level and other clinical markers in Japanese subjects with type 2 diabetes mellitus (n=133, 115 men and 18 women; age 64.7±11.5 years; HbA1c 8.1±1.6%). Plasma level of LL-37 was measured by ELISA. Results. Mean plasma LL-37 level was 71.2±22.3 ng/mL. Plasma LL-37 level showed significant correlations with HDL cholesterol (r=−0.450, P<0.01), triglyceride (r=0.445, P<0.01), and high sensitive C-reactive protein (r=0.316, P<0.01) but no significant correlation with age, body mass index, HbA1c, estimated glomerular filtration rate, 25-hydroxyvitamin D, or vitamin D binding protein. Multiple linear regression analysis showed significant correlations of plasma LL-37 level with HDL cholesterol (β=−0.411, P<0.01) and high sensitive C-reactive protein (β=0.193, P<0.05). Conclusion. Plasma LL-37 level was positively correlated with inflammatory markers and negatively correlated with HDL cholesterol in patients with type 2 diabetes mellitus

Relationship between Stage of Diabetic Retinopathy and Pulse Wave Velocity in Japanese Patients with Type 2 Diabetes

Objectives. We investigated the relationship between the stage of diabetic retinopathy and pulse wave velocity (PWV). Methods. This was a cross-sectional study of 689 patients (406 men and 283 women) with type 2 diabetes who were admitted to our hospital from 2004 to 2007. Brachial-ankle pulse wave velocity (baPWV) was measured by an arterial pressure measurement device as PWV/ABI. Diagnosis of diabetic retinopathy was made by ophthalmologists based on the Davis classification: no diabetic retinopathy (NDR), simple retinopathy (SDR), pre-proliferative retinopathy (pre-PDR), and proliferative retinopathy (PDR). Results. There was a significant difference in PWV between patients without diabetic retinopathy (1657.0 ± 417.9 m/s (mean ± SD)) and with diabetic retinopathy (1847.1 ± 423.9 m/s) (P < 0.001). In addition, the stage of diabetic retinopathy was associated with aortic PWV (1657.0 ± 417.9 m/s in NDR (n = 420), 1819.4 ± 430.3 m/s in SDR (n = 152), 1862.1 ± 394.0 m/s in pre-PDR (n = 54), and 1901.1 ± 433.5 m/s in PDR (n = 63) (P < 0.001)). Conclusions. In patients with diabetic retinopathy, even in those with SDR, PWV was higher than that in patients without diabetic retinopathy. Physicians should therefore pay attention to the value of PWV and macroangiopathy regardless of the stage of diabetic retinopathy

Plasma 25-Hydroxyvitamin D Is Independently Associated with Hemoglobin Concentration in Male Subjects with Type 2 Diabetes Mellitus

Introduction. It was reported that 25-hydroxyvitamin D level was independently associated with anemia in chronic kidney diseases, but the relation between vitamin D and anemia in diabetes mellitus is not still certain. We analyzed the relation between plasma 25-hydroxyvitamin D level and hemoglobin concentration. Materials and Methods. A cross-sectional study in male patients with type 2 diabetes was performed. Correlation coefficients and standardized partial regression coefficient for the hemoglobin concentration were evaluated. Results. Hemoglobin concentration was positively correlated with body mass index, HbA1c, estimated glomerular filtration rate, cholinesterase, and 25-hydroxyvitamin D level and negatively correlated with age, duration of diabetes mellitus, serum creatinine, and urinary albumin creatinine ratio. Multiple regression analysis revealed the independent relation of 25-hydroxyvitamin D to hemoglobin concentration. Conclusions. Plasma circulating form of vitamin D is significantly associated with hemoglobin concentration in diabetes mellitus independent of the clinical markers for kidney function or nutrition