Pre-existing Interstitial Lung Abnormalities and Immune Checkpoint Inhibitor-Related Pneumonitis in Solid Tumors: A Retrospective Analysis.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have demonstrated efficacy over previous cytotoxic chemotherapies in clinical trials among various tumors. Despite their favorable outcomes, they are associated with a unique set of toxicities termed as immune-related adverse events (irAEs). Among the toxicities, ICI-related pneumonitis has poor outcomes with little understanding of its risk factors. This retrospective study aimed to investigate whether pre-existing interstitial lung abnormality (ILA) is a potential risk factor for ICI-related pneumonitis. MATERIALS AND METHODS: Patients with non-small cell lung cancer, malignant melanoma, renal cell carcinoma, and gastric cancer, who was administered either nivolumab, pembrolizumab, or atezolizumab between September 2014 and January 2019 were retrospectively reviewed. Information on baseline characteristics, computed tomography findings before administration of ICIs, clinical outcomes, and irAEs were collected from their medical records. Pre-existing ILA was categorized based on previous studies. RESULTS: Two-hundred-nine patients with a median age of 68 years were included and 23 (11.0%) developed ICI-related pneumonitis. While smoking history and ICI agents were associated with ICI-related pneumonitis (P = .005 and .044, respectively), the categories of ILA were not associated with ICI-related pneumonitis (P = .428). None of the features of lung abnormalities were also associated with ICI-related pneumonitis. Multivariate logistic analysis indicated that smoking history was the only significant predictor of ICI-related pneumonitis (P = .028). CONCLUSION: This retrospective study did not demonstrate statistically significant association between pre-existing ILA and ICI-related pneumonitis, nor an association between radiologic features of ILA and ICI-related pneumonitis. Smoking history was independently associated with ICI-related pneumonitis. Further research is warranted for further understanding of the risk factors of ICI-related pneumonitis.

Exploration of postural effects on the external jugular and diploic venous system using upright computed tomography scanning.

PURPOSE: Few studies have investigated the influence of posture on the external jugular and diploic venous systems in the head and cranial region. In this study, we aimed to investigate the effects of posture on these systems using upright computed tomography (CT) scanning. METHODS: This study retrospectively analysed an upright CT dataset from a previous prospective study. In each patient, the diameters of the vessels in three external jugular tributaries and four diploic veins were measured using CT digital subtraction venography in both supine and sitting positions. RESULTS: Amongst the 20 cases in the original dataset, we eventually investigated 19 cases due to motion artifacts in 1 case. Compared with the supine position, most of the external jugular tributaries collapsed, and the average size significantly decreased in the sitting position (decreased by 22-49% on average). In contrast, most of the diploic veins, except the occipital diploic veins, tended to increase or remain unchanged (increased by 12-101% on average) in size in the sitting position compared with the supine position. However, the changes in the veins associated with this positional shift were not uniform; in approximately 5-30% of the cases, depending on each vein, an opposite trend was observed. CONCLUSION: Compared to the supine position, the contribution of external jugular tributaries to head venous drainage decreased in the sitting position, whilst most diploic veins maintained their contribution. These results could enhance our understanding of the physiology and pathophysiology of the head region in upright and sitting positions.

Estimating right atrial pressure using upright computed tomography in patients with heart failure.

OBJECTIVES: Upright computed tomography (CT) can detect slight changes particularly in the superior vena cava (SVC) volume in healthy volunteers under the influence of gravity. This study aimed to evaluate whether upright CT-based measurements of the SVC area are useful for assessing mean right atrial pressure (mRAP) in patients with heart failure. METHODS: We performed CT in both standing and supine positions to evaluate the SVC (directly below the junction of the bilateral brachiocephalic veins) and inferior vena cava (IVC; at the height of the diaphragm) areas and analyzed their relationship with mRAP, measured by right heart catheterization in 23 patients with heart failure. RESULTS: The median age of enrolled patients was 60 (51-72) years, and 69.6% were male. The median mRAP was 3 (1-7) mmHg. The correlations between the standing position SVC and IVC areas and mRAP were stronger than those in the supine position (SVC, ρ = 0.68, p < 0.001 and ρ = 0.43, p = 0.040; IVC, ρ = 0.57, p = 0.005 and ρ = 0.46, p = 0.026; respectively). Furthermore, the SVC area in the standing position was most accurate in identifying patients with higher mRAP (> 5 mmHg) (SVC standing, area under the receiver operating characteristic curve [AUC] = 0.91, 95% confidence interval [CI], 0.77-1.00; SVC supine, AUC = 0.78, 95% CI, 0.59-0.98; IVC standing, AUC = 0.77, 95% CI, 0.55-0.98; IVC supine, AUC = 0.72, 95% CI, 0.49-0.94). The inter- and intraobserver agreements (evaluated by intraclass correlation coefficients) for all CT measurements were 0.962-0.991. CONCLUSIONS: Upright CT-based measurement of the SVC area can be useful for non-invasive estimation of mRAP under the influence of gravity in patients with heart failure. KEY POINTS: • This study showed that the superior vena cava (SVC) area in the standing position was most accurate in identifying patients with heart failure with higher mean right atrial pressure. • Upright computed tomography-based measurements of the SVC area can be a promising non-invasive method for estimating mean right atrial pressure under the influence of gravity in patients with heart failure. • Clinical management of patients with heart failure based on this non-invasive modality may lead to early assessment of conditional changes and reduced hospitalization for exacerbation of heart failure.

Association between 1-year changes in urinary albumin-to-creatinine ratio and kidney disease progression in Japanese individuals with diabetes: a historical cohort study.

BACKGROUND: The National Kidney Foundation recently proposed a ≥ 30% decrease in urinary albumin-to-creatinine ratio (UACR) over 0.5-2 years as a surrogate endpoint for chronic kidney disease (CKD) progression in individuals with baseline UACR > 30 mg/g. This historical cohort study aimed to determine the applicability of a decrease in UACR, within as little as 1 year, as a surrogate endpoint for Japanese individuals with type 2 diabetes mellitus (T2D). METHODS: A total of 5067 individuals with T2D were divided into three groups based on 1-year change in UACR: ≥ 30% decrease (UACR decreased group), < 30% decrease and < 30% increase (UACR unchanged group), or ≥ 30% increase (UACR increased group). The primary endpoint was a composite of a ≥ 30% decline in estimated glomerular filtration rate (eGFR) or the initiation of kidney replacement therapy, whichever occurred first. RESULTS: At baseline, the proportions of individuals with normoalbuminuria, microalbuminuria, and eGFR ≥ 60 mL/min/1.73 m2 were 68.1%, 22.1%, and 75.5%, respectively. During a median follow-up of 6.8 years, 926 individuals (18.3%) reached the composite endpoint. Adjusted hazard ratios (vs. the UACR unchanged group) for the UACR decreased and increased groups were 0.758 (95% confidence interval [CI], 0.636-0.905; P = 0.002) and 1.304 (95% CI, 1.108-1.536; P = 0.001), respectively. CONCLUSIONS: These findings support the use of 1-year changes in UACR as a surrogate endpoint for the progression of CKD and the implementation of a ≥ 30% decrease in UACR as a positive efficacy endpoint in Japanese individuals with T2D and early-stage kidney disease.

Changes in urinary albumin as a surrogate for kidney disease progression in people with type 2 diabetes.

BACKGROUND: It remains unclear whether urinary albumin changes can predict subsequent kidney disease progression in people with diabetes. METHODS: This retrospective cohort study included 4570 Japanese adults with type 2 diabetes (T2D). The exposure was changes in urinary albumin-to-creatinine ratio (UACR) over 3 years, categorized into three categories: ≤ - 30%, minor change, or ≥ 30%. During the exposure period, eGFR decline was also examined and categorized into two categories: < 30% or ≥ 30% decline. The primary outcome was the composite of eGFR halving or initiation of kidney replacement therapy (KRT). The secondary outcome was the initiation of KRT. RESULTS: In the spline model, the hazard ratio for the primary outcome increased linearly on the log2 scale of UACR changes. When classified into six groups based on the categories of UACR changes and eGFR decline, people with a ≤ - 30% UACR change and < 30% eGFR decline had a 38% lower incidence of the outcome compared to those with a minor UACR change and < 30% eGFR decline. Meanwhile, the risk in those with a ≤ - 30% UACR change and ≥ 30% eGFR decline was 2.89 times. People with a ≥ 30% UACR change had the higher risk, regardless of whether a ≥ 30% eGFR decline occurred. Similar results were obtained in the secondary outcome. CONCLUSIONS: UACR changes can be a useful surrogate for kidney disease progression in people with T2D. However, when setting a decrease in UACR as the surrogate, it may be necessary to simultaneously evaluate kidney function decline.

Changes in the lumbar intervertebral foramen between supine and standing posture in patients with adult spinal deformity: a study with upright computed tomography.

OBJECTIVE: To quantitatively assess the impact of supine and standing positions on the morphological changes in the lumbar intervertebral foramen (LIF) in patients with adult spinal deformity (ASD) using upright CT and conventional supine CT. MATERIALS AND METHODS: Thirty patients with ASD were prospectively enrolled in this study. All subjects underwent standing whole spine posterior/anterior radiographs, lateral radiographs, and whole spine CT, both in the supine and upright standing positions. Two orthopedic surgeons independently measured nine radiographic parameters in the radiograph and the lumbar foraminal area (FA) and height (FH) in supine and upright CT. Statistical analyses were performed to evaluate the risk of LIF decrease when standing upright compared to the supine position. The chi-squared, t test, Pearson's coefficients, intra- and inter-rater reliabilities, and ROC curves were calculated. The level of significance was set at p < 0.05. RESULTS: Among the 300 LIFs, both the lumbar FA and FH were either increased or decreased by > 5% in approximately 30% of LIFs each. The FA decreased in the lower lumbar spine. The concave side had a significantly higher rate of decreased FA and FH than the convex side (p < 0.05 and < 0.05, respectively). ROC analysis showed that narrowing of the intervertebral disc (cutoff > 0.05°) is a risk factor for decreased FA and FH. CONCLUSIONS: This study describes the details of the changes in the neuroforamen using a novel upright CT. In patients with ASD, approximately 30% of LIFs either increased or decreased in size by > 5% when standing. The risk factors for LIF decrease are the lower lumbar spine, concave side, and narrow side of the disc wedge.

Kidney outcomes and all-cause mortality in people with type 2 diabetes exhibiting non-albuminuric kidney insufficiency.

AIM/HYPOTHESIS: It remains unclear whether people with diabetes exhibiting non-albuminuric kidney insufficiency have higher risk of kidney function decline and mortality compared with those exhibiting preserved kidney function without albuminuria. Furthermore, information regarding the incidence of albuminuria in people with this unique phenotype is sparse. Here, we aimed to elucidate the risk of the kidney outcomes and all-cause mortality in people with diabetes exhibiting non-albuminuric kidney insufficiency. METHODS: In this retrospective cohort study, 8320 Japanese adults with type 2 diabetes were classified into four groups based on the presence of albuminuria and kidney insufficiency at baseline, defined as urinary albumin/creatinine ratio of equal to or above 30 mg/g and eGFR of less than 60 ml min-1 1.73 m-2, respectively. The primary composite kidney endpoint was a 50% decrease in eGFR from baseline or the initiation of kidney replacement therapy. The annual percentage change in eGFR slope and progression of albuminuria category were evaluated as the secondary and tertiary kidney endpoints, respectively. All-cause death was also set as the endpoint. RESULTS: Compared with people exhibiting non-albuminuric preserved kidney function, those with non-albuminuric kidney insufficiency had the higher risk for the primary kidney endpoint (HR 4.1; 95% CI 2.5, 6.7; p < 0.001), steep percentage change in eGFR slope (-1.96%/year vs -1.36%/year, p < 0.001), incidence of albuminuria (HR 2.1; 1.7, 2.6; p < 0.001) and all-cause mortality (HR 1.5; 1.2, 2.0; p = 0.003). In the sensitivity analyses treating the incidence of albuminuria as a competing risk, people with non-albuminuric kidney insufficiency still had higher risk for the primary kidney endpoint and all-cause mortality than those with non-albuminuric preserved kidney function (subdistribution HR 2.8; 1.4, 5.6; p = 0.004; and 1.6; 1.1, 2.2; p = 0.014, respectively). CONCLUSIONS/INTERPRETATION: People with type 2 diabetes exhibiting non-albuminuric kidney insufficiency had poorer kidney outcomes and life prognosis than those exhibiting non-albuminuric preserved kidney function.

Comparison of Lung, Lobe, and Airway Volumes between Supine and Upright Computed Tomography and Their Correlation with Pulmonary Function Test in Patients with Chronic Obstructive Pulmonary Disease.

BACKGROUND: Correlations between upright CT and pulmonary function test (PFT) measurements, and differences in lung/lobe/airway volumes between supine and standing positions in patients with chronic obstructive pulmonary disease (COPD) remain unknown. OBJECTIVES: The study aimed to evaluate correlations between lung/airway volumes on both supine and upright CT and PFT measurements in patients with COPD, and compare CT-based inspiratory/expiratory lung/lobe/airway volumes between the two positions. METHODS: Forty-eight patients with COPD underwent both conventional supine and upright CT in a randomized order during inspiration and expiration breath-holds, and PFTs within 2 h. We measured the lung/lobe/airway volumes on both CT. RESULTS: The correlation coefficients between total lung volumes on inspiratory CT in supine/standing position and PFT total lung capacity and vital capacity were 0.887/0.920 and 0.711/0.781, respectively; between total lung volumes on expiratory CT in supine/standing position and PFT functional residual capacity and residual volume, 0.676/0.744 and 0.713/0.739, respectively; and between airway volume on inspiratory CT in supine/standing position and PFT forced expiratory volume in 1 s, 0.471/0.524, respectively. Inspiratory/expiratory bilateral upper and right lower lobe, bilateral lung, and airway volumes were significantly higher in the standing than supine position (3.6-21.2% increases, all p < 0.05); however, inspiratory/expiratory right middle lobe volumes were significantly lower in the standing position (4.6%/15.9% decreases, respectively, both p < 0.001). CONCLUSIONS: Upright CT-based volumes were more correlated with PFT measurements than supine CT-based volumes in patients with COPD. Unlike other lobes and airway, inspiratory/expiratory right middle lobe volumes were significantly lower in the standing than supine position.

Relationship between hip joint proximity area and sagittal balance parameters: an upright computed tomography study.

PURPOSE: A close relationship between sagittal spinal alignment and hip osteoarthritis (OA) has been documented. This study aimed to examine the relationship between hip joint proximity area and sagittal balance parameters in healthy subjects. METHODS: This prospective study enrolled 47 healthy volunteers who underwent 320-detector row upright computed tomography. Acquired data were reconstructed in a virtual three-dimensional space. The proximity area was determined by < 1 mm of the Hausdorff distance between the acetabulum and the femoral head. Volunteers were divided into the anterior and posterior proximity groups depending on the position of the closest area. Sagittal balance parameters [sagittal vertical axis (SVA), T1 spinopelvic inclination (T1-SPi), T1-pelvic angle, pelvic tilt, sacral slope, pelvic incidence, lumbar lordosis, thoracic kyphosis), offset distance between the centre of the acoustic meati (CAM) and C7 plumb line (CAM-C7-offset), and offset distance between the CAM and hip axis (HA) (CAM-HA-offset)] were compared between the two groups using independent sample t test. RESULTS: The anterior proximity group (n = 24) had higher SVA (p = 0.016) and T1-Spi (p = 0.015) than the posterior proximity group (n = 23). CAM-HA-offset was higher in the posterior than in the anterior proximity group (p < 0.000). There was no difference in other parameters (p > 0.05). CONCLUSION: The anterior proximity group had a positive anterior spinal balance; the posterior proximity group may have a more posterior gravity line than the hip joint centre. The anterior spinal balance may contribute to the anterior loading of the hip joint, with known relation with the initiation and onset of hip OA.

Three-Dimensional Quantitative Evaluation of the Scapular Skin Marker Movements in the Upright Posture.

Motion capture systems using skin markers are widely used to evaluate scapular kinematics. However, soft-tissue artifact (STA) is a major limitation, and there is insufficient knowledge of the marker movements from the original locations. This study explores a scapular STA, including marker movements with shoulder elevation using upright computed tomography (CT). Ten healthy males (twenty shoulders in total) had markers attached to scapular bony landmarks and underwent upright CT in the reference and elevated positions. Marker movements were calculated and compared between markers. The bone-based and marker-based scapulothoracic rotation angles were also compared in both positions. The median marker movement distances were 30.4 mm for the acromial angle, 53.1 mm for the root of the scapular spine, and 70.0 mm for the inferior angle. Marker movements were significantly smaller on the superolateral aspect of the scapula, and superior movement was largest in the directional movement. Scapulothoracic rotation angles were significantly smaller in the marker-based rotation angles than in the bone-based rotation angles of the elevated position. We noted that the markers especially did not track the inferior movement of the scapular motion with shoulder elevation, resulting in an underestimation of the marker-based rotation angles.

Differences in airway lumen area between supine and upright computed tomography in patients with chronic obstructive pulmonary disease.

BACKGROUND: No clinical studies to date have compared the inspiratory and expiratory airway lumen area between supine and standing positions. Thus, the aims of this study were twofold: (1) to compare inspiratory and expiratory airway lumen area (IAA and EAA, respectively) on computed tomography (CT) among supine and standing positions; and (2) to investigate if IAA and EAA are associated with lung function abnormality in patients with chronic obstructive pulmonary disease (COPD). METHODS: Forty-eight patients with COPD underwent both low-dose conventional (supine position) and upright CT (standing position) during inspiration and expiration breath-holds and a pulmonary function test (PFT) on the same day. We measured the IAA and EAA in each position. RESULTS: For the trachea to the third-generation bronchi, the IAA was significantly larger in the standing position than in the supine position (4.1-4.9% increase, all p < 0.05). The EAA of all bronchi was significantly larger in the standing position than in the supine position (9.7-62.5% increases, all p < 0.001). The correlation coefficients of IAA in the standing position and forced expiratory volume in 1 s were slightly higher than those in the supine position. The correlation coefficients of EAA or EAA/IAA in the standing position and residual volume, and the inspiratory capacity/total lung capacity ratio were higher than those in the supine position. CONCLUSIONS: Airway lumen areas were larger in the standing position than in the supine position. IAAs reflect airway obstruction, and EAAs reflect lung hyperinflation. Upright CT might reveal these abnormalities more precisely. Trial registration University Hospital Medical Information Network (UMIN 000026587), Registered 17 March 2017. URL: https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000030456 .

Anatomic and diagnostic considerations of facial mobility for understanding the effectiveness of facial massage: A pilot study.

BACKGROUND: The effectiveness of facial massage is often explained by the resulting increases in the blood and lymphatic flow. However, it is difficult to explain the lifting effect on the cheeks. The aim of this study was to analyze facial mobility to further current understanding of the effectiveness of facial massage. MATERIALS AND METHODS: Two kinds of analytical methods were designed using a cadaveric head as well as advanced computed tomography (CT). The cadaveric face was divided into three sections, and three different colors of ink were injected into each section. It was kept in a supine position for 24 hours, and the ink distribution was observed. Upright and supine CT examinations were performed on six healthy adult volunteers. The images of both were superimposed by a three-dimensional image analysis system, and changes in facial contours were analyzed. RESULTS: The three colors of ink spread craniocaudally and were distributed differently from the gravitational vector. When both CT images were superimposed, two distinct lines were formed, which represented overlapping of the facial contours due to the two different CT images. These lines were found to correspond to the border of each color of the ink. CONCLUSION: Focusing on the mobility of the face, the soft tissue of the face had vertical mobility, and it was speculated that this mobility is involved in the effectiveness of facial massage. Our results could provide useful information for cosmetic treatment and contribute to the collection of scientific knowledge for anti-aging medicine.

Determining the validity and reliability of spinopelvic parameters through comparing standing whole spinal radiographs and upright computed tomography images.

BACKGROUND: Standing whole spinal radiographs are used to evaluate spinal alignment in adult spinal deformity (ASD), yet some studies have reported that pelvic incidence, pelvic tilt, and thoracic kyphosis (TK) intra- and inter-observer reliability is low. This study aimed to evaluate the accuracy of spinopelvic parameters through comparing standing whole spinal radiographs and upright CT images. METHODS: We enrolled 26 patients with ASD. All standing whole spinal posterior/anterior and lateral radiographs and upright whole spinal CT had been obtained in a natural standing position. Two examiners independently measured 13 radiographic parameters. Interclass correlation coefficients (ICCs) were used to analyze measurement intra- and inter-observer reliability. Paired t- and Pearson's correlation tests were used to analyze validity of the standing whole spinal radiographs. RESULTS: ICCs of upright CT were excellent in both intra- and inter-observer reliability. However, intra-observer ICCs for TK2-12, TK1-5, TK2-5, and TK5-12 on standing lateral radiographs were relatively low, as were inter-observer ICCs for TK2-12, TK1-5, TK2-5, and TK5-12. Concerning TK values, the difference between the radiographs and CT in TK1-12 and TK2-12 were 4.4 ± 3.1 and 6.6 ± 4.6, respectively, and TK values from T2 showed greater measurement error (p < 0.05). CONCLUSIONS: Upright CT showed excellent intra- and inter-observer reliability in the measurement of spinopelvic parameters. Measurement of TK with T2 on standing whole spinal radiographs resulted in a greater measurement error of up to 6.6°. Surgeons need to consider this when planning surgery and measuring postoperative TK changes in patients with ASD.

Difference in the airway luminal area between the standing and supine positions using upright and conventional computed tomography.

No clinical studies to date have compared the airway luminal area between supine and standing positions. Our aim was therefore to compare the airway luminal area between these two positions on computed tomography (CT) and to determine its correlation with forced expiratory volume in 1 s (FEV1). Thirty-two asymptomatic volunteers underwent both conventional (supine position) and upright (standing position) CT during deep inspiration breath-holding. Pulmonary function tests were conducted on the same day. We measured the airway luminal area on CT in each position. Paired t-tests and Pearson's correlation coefficients were used for statistical analysis. The average luminal areas of the trachea, right and left main bronchi, and average third-generation airway were greater in the standing than the supine position by 3.4%, 6.1%, 5.5%, and 5.2%, respectively. The correlation coefficients between airway luminal areas and FEV1 tended to be higher in the standing than the supine position; this correlation was highest for the average third-generation airway (r = 0.70, P < 0.0001). The airway luminal areas of the trachea, bilateral main bronchi, and average third-generation airway were greater in the standing than the supine position. The average third-generation airway area in the standing position had the highest correlation with FEV1.

Pelvic floor morphology in the standing position using upright computed tomography: age and sex differences.

INTRODUCTION AND HYPOTHESIS: This study was aimed at comparing pelvic floor parameters between the standing and supine positions using upright computed tomography (CT) and evaluating the effects of sex and age in normal healthy volunteers. METHODS: In total, 139 volunteers (70 men, mean 46.7 years; 69 women, mean 47.3 years) underwent both upright CT in the standing position and conventional CT in the supine position. The distances from the bladder neck to the pubococcygeal line (PCL) and anorectal junction (ARJ), defined as the posterior aspect of the puborectalis muscle, to PCL were measured. The length, width, and area of the levator hiatus (LH) were measured on oblique axial images. RESULTS: The bladder neck (men, 22.2 ± 4.9 mm vs 28.3 ± 5.3 mm; women, 9.0 ± 5.1 mm vs 19.0 ± 4.0 mm) and ARJ (men, -18.8 ± 5.5 mm vs -12.1 ± 5.1 mm; women, -20.0 ± 4.7 mm vs -11.2 ± 4.3 mm) were significantly lower in the standing position than in the supine position (all p < 0.0001). The LH area (men, 1,990 ± 380 mm2 vs 1,697 ± 329 mm2; women, 2,284 ± 344 mm2 vs 1,811 ± 261 mm2) was significantly larger in the standing position (both p < 0.0001). Differences in all parameters between the standing and supine positions were larger in women than in men. ARJ in women showed a significant tendency to descend with age only in the standing position (r = -0.29, p = 0.017). CONCLUSIONS: The bladder neck and ARJ descend and the LH area enlarges in the standing position. Pelvic floor mobility is greater in women than in men. Descent of the ARJ in the standing position is associated with aging in women.

Differences in Lung and Lobe Volumes between Supine and Standing Positions Scanned with Conventional and Newly Developed 320-Detector-Row Upright CT: Intra-Individual Comparison.

BACKGROUND: No clinical studies to date have compared unilateral lung or lobe volumes between the supine and standing positions. OBJECTIVES: To compare lung/lobe volumes on computed tomography (CT) between these two positions and evaluate the correlation between the total lung volume and total lung capacity (TLC) on pulmonary function tests (PFTs). METHODS: Thirty-two asymptomatic volunteers underwent both conventional CT (supine position) and upright CT (standing position), during deep inspiration breath-hold, and PFTs on the same day. We measured lung/lobe volumes on CT in each position. Paired t tests were used for statistical analysis. RESULTS: The volumes of the total lung (10.9% increase), right lung (10.3% increase), right upper lobe (8.6% increase), right lower lobe (14.6% increase), left lung (11.6% increase), left upper lobe (7.1% increase), and left lower lobe (16.0% increase) were significantly greater in the standing position than in the supine position (all p < 0.0001). The right middle lobe volume was similar between the two positions (p = 0.16). Intraclass correlation coefficients for agreement between total lung volumes on CT in the supine/standing positions and the TLC on PFT were 0.891/0.938, respectively. CONCLUSIONS: While the volumes of the bilateral upper and lower lobes and bilateral lungs were significantly greater in the standing than in the supine position, with lower lobes showing larger changes, the right middle lobe volume did not change significantly between positions. The total lung volume on upright CT in the standing position was more similar to TLC on PFT than that in the supine position.

Sinking skin flap syndrome visualized by upright computed tomography.

Sinking skin flap syndrome is a craniectomy complication characterized by new neurological dysfunction that typically worsens in the upright position and improves after cranioplasty. We present a 33-year-old man who experienced hemiparesis in the upright position after craniectomy. Upright computed tomography (CT) before cranioplasty showed a remarkable shift of the brain compared to supine CT. After cranioplasty, both symptoms and brain shift on CT resolved. Upright CT enables detection and objective evaluation of paradoxical herniation and midline shift that is not obvious on supine imaging modalities. Clinicians need to be aware of positional brain shift in postcraniectomy patients.

Effects of uric acid on kidney function decline differ depending on baseline kidney function in type 2 diabetic patients.

BACKGROUND: Most existing data regarding effects of uric acid (UA) on diabetic kidney disease have considered patients with preserved kidney function. We examined a hypothesis that there are differences in the effects of serum UA levels on the decline in kidney function depending on baseline kidney function in diabetic patients. METHODS: In this historical cohort study, 7033 type 2 diabetic patients were analyzed and classified into two groups as follows: nonchronic kidney disease (non-CKD), with an estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 (n = 4994), and CKD, with an eGFR <60 mL/min/1.73 m2 (n = 2039). The composite endpoint was a ≥30% decrease in eGFR from baseline or the initiation of renal replacement therapy. The hazard ratio (HR) of serum UA levels at baseline was estimated using multivariate Cox proportional hazards models. RESULTS: There was a significant interaction between UA levels and baseline eGFR with respect to the endpoint (P < 0.001). The HRs of 1 mg/dL increase in UA levels were 1.13 [95% confidence interval (CI) 1.05-1.22, P = 0.002] and 0.93 (95% CI 0.88-0.99, P = 0.02) in the non-CKD and CKD groups, respectively. When patients were classified by quintile of UA levels, the HRs of those in the 5th quintile (versus 1st quintile) were 1.64 (95% CI 1.23-2.18, P < 0.001) and 0.76 (95% CI 0.58-0.99, P = 0.05) in the non-CKD and CKD groups, respectively. CONCLUSIONS: The effects of UA on kidney function decline might differ depending on baseline kidney function in type 2 diabetic patients. High UA levels are the prognostic factor only in patients with preserved kidney function.

Effect of natural full weight-bearing during standing on the rotation of the first metatarsal bone.

To evaluate the rotational change in the first metatarsal bone (1MT) of the foot during natural standing using an upright computed tomography (CT) scanner with 320-detector rows. A total of 52 feet of 28 asymptomatic subjects (aged 23-39 years) were evaluated in the natural standing position with or without weight-bearing. A foot pressure plate was used to determine the non-weight-bearing (NWB) or single leg full-weight-bearing (s-FWB) conditions. CT examinations were performed using a noise index of 15 for a slice thickness of 5 mm, rotation speed of 0.5 sec, and slice thickness of 0.5 mm. The rotation of the 1MT was measured on the coronal CT image, which cut the sesamoids' bellies in the frontal slide of the first metatarsal and sesamoids perpendicular to the longitudinal bisection of the third metatarsal, and compared between the weight-bearing conditions. Intra- and inter-observer reliabilities of the rotation angle were also evaluated. The intra- and inter-observer correlation coefficients were 0.961 and 0.934, respectively. The 1MT pronation angle was significantly greater in the s-FWB condition than in the NWB condition (15.2° ± 5.4° vs. 12.5° ± 5.3°, P < 0.01). No sex difference was found in the magnitude of the 1MT pronation angle as a result of weight-bearing. This study first demonstrated that pronation of 1MT occurs due to natural full-weight-bearing in asymptomatic feet. The 1MT's rotational movement under weight-bearing conditions may relate to the onset and pathogenesis of the hallux valgus. Clin. Anat. 32:715-721, 2019. © 2019 Wiley Periodicals, Inc.

The influence of seated postures and anthropometry on lap belt fit in vehicle occupants: A 3D computed tomography study.

OBJECTIVE: In vehicle frontal collisions, it is crucial that the lap belt is designed to engage with the anterior superior iliac spine (ASIS) of occupants for a reliable restraint. This study aims to understand the influence of different seated postures on the geometrical relationship of the seat belt and the pelvis for various occupants using 3D upright and supine computed tomography (CT) systems. METHODS: The 3D shapes of bones and soft tissues around the pelvis were acquired through a CT scan for 30 participants. They were seated in a rigid seat equipped with a lap belt simulating the front seat of a small car, and wore a lap belt in three seated postures: upright, slouched and reclined. Parameters related to the likelihood of submarining occurrences, such as belt-ASIS overlap (an index for assessing the potential engagement of the lap belt with the ASIS) and the belt-pelvis angle (the difference between the belt angle and the normal direction of the anterior edge of the ilium) were compared. RESULTS: It was observed that the pelvis angle tilted rearward as the hip point was positioned forward and seatback angle increased. This can be seen in the slouched and reclined posture. The belt-pelvis angle was comparable between the slouched and the reclined postures, and was closer to zero (indicating that the lap belt path is closer to perpendicular to the anterior edge of the ilium) compared to the upright posture. In contrast, the belt-ASIS overlap increased with an increasing flesh margin of the ASIS and shallower belt angle. This suggests that the belt-pelvis angle is influenced by the seated posture whereas the belt-ASIS overlap is dependent more on an individual's anthropometry. The plot of belt-pelvis angle and belt-ASIS overlap exhibited significant variability among participants. CONCLUSIONS: The belt-pelvis angle and the belt-ASIS overlap of individuals will provide valuable information for understanding the current belt-fit location and predicting submarining occurrences for individuals in various postures when designing restraint systems.