Opportunistic use of chest low-dose computed tomography (LDCT) imaging for low bone mineral density and osteoporosis screening: cutoff thresholds for the attenuation values of the lower thoracic and upper lumbar vertebrae.

Background: Osteoporosis remains substantially underdiagnosed and undertreated worldwide. Chest low-dose computed tomography (LDCT) may provide a valuable and popular opportunity for osteoporosis screening. This study sought to evaluate the feasibility of the screening of low bone mineral density (BMD) and osteoporosis with mean attenuation values of the lower thoracic compared to upper lumbar vertebrae. The cutoff thresholds of the mean attenuation values in Hounsfield units (HU) were derived to facilitate implementation of opportunistic screening using chest LDCT. Methods: The participants aged 30 years or older who underwent chest LDCT and quantitative computed tomography (QCT) examinations from August 2018 to October 2020 in our hospital were consecutively included in this retrospective study. A region of interest (ROI) was placed in the trabecular bone of each vertebral body to measure the HU values. The correlations of mean HU values of lower thoracic (T11-T12) and upper lumbar (L1-L2) vertebrae with age and lumbar BMD obtained with QCT were performed using the Pearson correlation coefficient, respectively. The area under the curve (AUC) of the receiver operator characteristic (ROC) curve was generated to determine the cutoff thresholds for distinguishing low BMD from normal and osteoporosis from non-osteoporosis. Results: A total of 1,112 participants were included in the final study cohort (743 men and 369 women, mean age 58.2±8.9 years; range, 32-88 years). The mean HU values of T11-T12 and L1-L2 were significantly different among 3 QCT-defined BMD categories of osteoporosis, osteopenia, and normal (P<0.001). The differences in HU values between T11-T12 and L1-L2 in each category of bone status were statistically significant (P<0.001). The mean HU values of T11-T12 (r=-0.453, P<0.001) and L1-L2 (r=-0.498, P<0.001) had negative correlations with age. Positive correlations were observed between the mean HU values of T11-T12 (r=0.872, P<0.001) and L1-L2 (r=0.899, P<0.001) with BMD. The optimal cutoff thresholds for distinguishing low BMD from normal were average T11-T12 ≤157 HU [AUC =0.941, 95% confidence interval (CI): 0.925-0.954, P<0.001] and L1-L2 ≤138 HU (AUC =0.950, 95% CI: 0.935-0.962, P<0.001), as well as distinguishing osteoporosis from non-osteoporosis were average T11-T12 ≤125 HU (AUC =0.960, 95% CI: 0.947-0.971, P<0.001) and L1-L2 ≤107 HU (AUC =0.961, 95% CI: 0.948-0.972, P<0.001). There was no significant difference between the AUC values of T11-T12 and L1-L2 for low BMD (P=0.07) and osteoporosis (P=0.92) screening. Conclusions: We have conducted a study on low BMD and osteoporosis screening using mean attenuation values of lower thoracic and upper lumbar vertebrae. Assessment of mean attenuation values of T11-T12 and L1-L2 can be used interchangeably for low BMD and osteoporosis screening using chest LDCT, and their cutoff thresholds were established.

Retrolaminar migration as a complication of intraocular silicone oil injection detected on unenhanced CT.

AIM: To describe the clinical and radiologic features of retrolaminar migration silicone oil (SiO) and observe the dynamic position of ventricular oil accumulation in supine and prone. METHODS: For this retrospective study, 29 patients who had a history of SiO injection treatment and underwent unenhanced head computed tomography (CT) were included from January 2019 to October 2022. The patients were divided into migration-positive and negative groups. Clinical history and CT features were compared using Whitney U and Fisher's exact tests. The dynamic position of SiO was observed within the ventricular system in supine and prone. CT images were visually assessed for SiO migration along the retrolaminar involving pathways for vision (optic nerve, chiasm, and tract) and ventricular system. RESULTS: Intraocular SiO migration was found in 5 of the 29 patients (17.24%), with SiO at the optic nerve head (n=1), optic nerve (n=4), optic chiasm (n=1), optic tract (n=1), and within lateral ventricles (n=1). The time interval between SiO injection and CT examination of migration-positive cases was significantly higher than that of migration-negative patients (22.8±16.5mo vs 13.1±2.6mo, P<0.001). The hyperdense lesion located in the frontal horns of the right lateral ventricle migrated to the fourth ventricle when changing the position from supine to prone. CONCLUSION: Although SiO retrolaminar migration is unusual, the clinician and radiologist should be aware of migration routes. The supine combined with prone examination is the first-choice method to confirm the presence of SiO in the ventricular system.

An inverted U-shaped relationship between parathyroid hormone and body weight, body mass index, body fat.

PURPOSE: To investigate the relationship between parathyroid hormone (PTH) levels and body weight, body mass index (BMI), lipid profiles, and fat distribution in subjects with primary hyperparathyroidism (PHPT) and controls. METHODS: This was a cross-sectional study in 192 patients with PHPT and 202 controls. Serum concentrations of calcium, 25-hydroxyvitamin D (25(OH)D), PTH, lipids profiles, and other hormones were quantified. Bone mineral density was assessed by dual-energy X-ray absorptiometry. Fat distribution evaluation utilizing quantitative computed tomography was conducted in another 66 patients with PHPT and 155 controls. RESULTS: PHPT patients were older (P < 0.001) and had less body weight (P < 0.001), lower BMI (P = 0.019), lower serum concentrations of 25(OH)D (P < 0.001), total cholesterol (P = 0.036), low-density lipoprotein-cholesterol (P = 0.036), and higher circulating concentration of free fatty acid (FFA) (P = 0.047) as compared with controls. After adjusting multiple confounders, PTH was positively correlated with weight (r = 0.311, P < 0.001), BMI (r = 0.268, P < 0.01), and visceral adipose tissue area (VAA) (r = 0.191, P < 0.05) in the first tertile of PTH. However, these associations were not observed in the second tertile. While in the third tertile, PTH was negatively correlated with weight (r = -0.200, P < 0.05), BMI (r = -0.223, P < 0.05) and marginally with VAA (r = -0.306, P = 0.065), it showed positive association with FFA (r = 0.230, P < 0.05). CONCLUSIONS: The inverted U-shape relationship between PTH and body weight, BMI, VAA found in this study is helpful to explain the conflicting results among these parameters, and extend our understanding of the metabolic effects of PTH.

The clinical features and reproductive prognosis of ovarian neoplasms with hyperandrogenemia: a retrospective analysis of 33 cases.

The aim of this study is to review the natural course, clinical features, and reproductive prognosis of ovarian tumors associated with hyperandrogenemia. We retrospect 33 patients of ovarian tumors with hyperandrogenemia. Thirty cases (91%) were sex cord-stromal tumors. Sertoli-Leydig cell tumors, Leydig cell tumors, and steroid cell tumors were the most common types. It is not possible, to predict the pathological subtypes based on androgen levels alone. Most of these tumors were solid masses, with an average diameter of 3.9 cm. These tumors are soft or fragile, no clear boundary with normal tissue, thus excision is superior to exfoliation. The average disease course of the top three tumors was 32.6, 35.4, and 67.7 months, respectively. Among 11 married women with a desire to get pregnant, nine cases resumed menstrual periods after surgery and became pregnant naturally. Hyperandrogenemia might predict a better prognosis. The asynchronism of hyperandrogenemia and undetectable tumor may cause irreversible change and emotional depress, the methods of early diagnosis need further study.