Gender differences in spinal mobility during postural changes: a detailed analysis using upright CT

Lumbar spinal alignment is crucial for spine biomechanics and is linked to various spinal pathologies. However, limited research has explored gender-specific differences using CT scans. The objective was to evaluate and compare lumbar spinal alignment between standing and sitting CT in healthy individuals, focusing on gender differences. 24 young and 25 elderly males (M) and females (F) underwent standing and sitting CT scans to assess lumbar spinal alignment. Parameters measured and compared between genders included lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), lordotic angle (LA), foraminal height (FH), and bony boundary area (BBA). Females showed significantly larger changes in SS and PT when transitioning from standing to sitting (p = .044, p = .038). A notable gender difference was also observed in the L4-S LA among the elderly, with females showing a significantly larger decrease in lordotic angle compared to males (- 14.1° vs. - 9.2°, p = .039*). Females consistently exhibited larger FH and BBA values, particularly in lower lumbar segments, which was more prominent in the elderly group (M vs. F: L4/5 BBA 80.1 mm2 [46.3, 97.8] vs. 109.7 mm2 [74.4, 121.3], p = .019 in sitting). These findings underline distinct gender-related variations in lumbar alignment and flexibility, with a focus on noteworthy changes in BBA and FH in females. Gender differences in lumbar spinal alignment were evident, with females displaying greater pelvic and sacral mobility. Considering gender-specific characteristics is crucial for assessing spinal alignment and understanding spinal pathologies. These findings contribute to our understanding of lumbar spinal alignment and have implications for gender-specific spinal conditions and treatments.

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.

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.

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.

Predictive modeling of submarining risk in car occupants based on pelvis angle and lap belt positioning

OBJECTIVE

The engagement of the lap belt with the pelvis is critical for occupant safety during vehicle frontal crashes to prevent occupant submarining. This study aims to develop a predictive model for submarining risk based on anthropometric parameters and lap belt positioning using finite element (FE) analyses.

METHODS

FE analyses were conducted using human body models representing various body shapes (a 50th percentile male, low and high BMI males, and a 5th percentile female) in three seated postures (standard, reclined, and slouched). The lap belt-ASIS overlap and the belt-pelvis angle were used as key parameters for predicting submarining risk. A logistic regression analysis was utilized to correlate submarining occurrence with the initial values of these two parameters at the beginning of impact. Subsequently, this submarining prediction model was applied to computer tomography (CT) measurements of human subjects in different seated postures (upright, reclined, and slouched), and submarining risks were calculated based on the developed model.

RESULTS

FE simulations indicated that submarining was more likely to occur as the initial belt-pelvis angle approached zero and there was a smaller initial belt-ASIS overlap. The logistic regression analysis demonstrated that the initial belt-pelvis angle and belt-ASIS overlap were statistically significant for predicting submarining risk. The derived model effectively distinguished submarining occurrence based on the initial values of these two parameters. The application of the submarining model to CT measurements of human subjects showed that submarining risk was lower in the order of upright, slouched, and reclined postures. In the reclined posture, the high submarining risk was attributed to a small belt-ASIS overlap and a rearward-tilted pelvis angle; whereas in the slouched posture, the risk was mostly associated with a rearward-tilted pelvis angle.

CONCLUSIONS

The submarining prediction model was developed based on the belt-pelvis angle and the belt-ASIS overlap. This predictive model may help to design restraint systems for various body types and seated postures of occupants.

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.

Anatomical cardiac and electrocardiographic axes correlate in both upright and supine positions: an upright/supine CT study

The correlation between the anatomical cardiac and electrocardiographic axes has been discussed for several years. Using upright computed tomography, this study aimed to reveal the relationship between the anatomical cardiac and electrocardiographic axes in both the supine and upright positions. Upright CT and standard supine CT were performed for healthy volunteers, following electrocardiography in both upright and supine position. On CT images, the coordinates of apex, the center of aortic valve (AV) and mitral valve (MV) were recorded, and the vectors and angles were calculated. Subcutaneous and visceral fat volume were semi-automatically calculated in a workstation. From a total 190 volunteers, 41 males were performed electrocardiography and included for this study. The QRS and anatomical axes (AV-apex and MV-apex axis) were significantly correlated in both supine and upright positions, while the angle of the AV-apex to Z axis was the most correlated (supine: r = - 0.54, p = 0.0002, upright: r = - 0.47, p = 0.0020). The anatomical axis moved in the dorsal and caudal directions from the supine to upright position. Multiple regression analysis revealed that the anatomical axis from the AV-apex to the Z-axis was determined according to age, body height, subcutaneous and visceral fat volumes.

Dynamic evaluation of the sternoclavicular and acromioclavicular joints using an upright four-dimensional computed tomography

In the analysis of the shoulder complex, the sequential changes occurring in the sternoclavicular and acromioclavicular joints during active shoulder motion are challenging to track. This study aimed to investigate the in vivo sternoclavicular and acromioclavicular joint motions during active elevation, including the sequential changes in these joint spaces using upright four-dimensional computed tomography (4DCT). Bilateral shoulders of 12 healthy volunteers upright 4DCT were obtained during active elevation similar to a "hands up" motion. The sternoclavicular and acromioclavicular rotation angles, joint distances, and closest points on the clavicle relative to the thorax and scapula were evaluated during 10°-140° of humerothoracic elevation. During humerothoracic elevation, the clavicle elevated, retracted, and rotated posteriorly relative to the thorax, whereas the scapula rotated upwardly, internally, and posteriorly relative to the clavicle. All the sternoclavicular and acromioclavicular joint rotation angles were significantly different at ≥ 30°-50° of humerothoracic elevation compared with 10° of humerothoracic elevation. The mean sternoclavicular and acromioclavicular joint distances were 2.2 ± 1.1 mm and 1.6 ± 0.9 mm, respectively. The closest points were located on the anteroinferior part of the medial and lateral clavicle in the sternoclavicular and acromioclavicular joints, respectively. Significant differences were observed in the acromioclavicular joint distance and anterior/posterior movements of the closest points in the sternoclavicular and acromioclavicular joints compared with 10° of humerothoracic elevation. Our sternoclavicular and acromioclavicular closest point results indicate that the impingement tends to occur at the anteroinferior part of the medial and lateral aspects of the clavicle and may be related to osteoarthritis.

Cross-Sectional and Longitudinal Associations of Creatinine-to-Cystatin C Ratio with Sarcopenia Parameters in Older Adults

OBJECTIVES

Accumulating evidence from cross-sectional studies suggests that the serum creatinine-to-cystatin C ratio (CCR) may be a useful biomarker for sarcopenia. This study aimed to assess the cross-sectional and longitudinal associations of CCR with sarcopenia and its parameters in community-dwelling older adults.

DESIGN

Cross-sectional and longitudinal study.

SETTING AND PARTICIPANTS

This 6-year prospective cohort study included the repeated measurement data from 1,253 Japanese residents (662 males and 591 females) aged ≥65 years who underwent medical checkups in Kusatsu and Hatoyama, Japan. A total of 4,421 observations were collected.

MEASUREMENTS

The CCR was grouped into quartiles by sex (Q1-Q4) using Q4 as the reference category. Sarcopenia was defined according to the Asian Working Group for Sarcopenia 2019 algorithm. Skeletal muscle mass index (SMI) measured using segmental multifrequency bioelectrical impedance analysis, handgrip strength (HGS), usual gait speed (UGS), and maximal gait speed (MGS) were measured repeatedly as sarcopenia parameters. The association of the CCR with changes in sarcopenia, SMI, HGS, UGS, and MGS during the 6-year period were analyzed using a generalized linear mixed-effects model.

RESULTS

The prevalence of sarcopenia at baseline was 13.1% (11.9% in males and 14.5% in females). In a cross-sectional analysis, the CCR quartile was inversely associated with sarcopenia and was positively associated with SMI, HGS, and MGS (P for trend < 0.001). In a longitudinal analysis during the 6 years, a significant increase in sarcopenia in Q2 (B = 1.1% point/year; P = 0.026 for group-by-time interaction) and significant declines in SMI (B = -0.01 kg/m2/year; P = 0.044 for group-by-time interaction) and MGS (B = -0.008 m/sec/year; P = 0.041 for group-by-time interaction) in Q1 were observed compared with Q4. However, the dose-response relationship was significant only for MGS (P = 0.033 for trend). No significant group-by-time interaction was observed for HGS. CCR was not significantly associated with UGS either cross-sectionally or longitudinally.

CONCLUSIONS

CCR is a useful biomarker regarding the status of sarcopenia. It may be used for sarcopenia screening even in older adults whose physical function is difficult to assess. However, further longitudinal studies are needed to determine whether CCR can be a predictor of future sarcopenia.

Three-dimensional shoulder kinematics: Upright four-dimensional computed tomography in comparison with an optical three-dimensional motion capture system

Although shoulder kinematics have been analyzed by various methods, dynamic shoulder motion is difficult to track. This study aimed to validate the shoulder kinematic analysis using upright four-dimensional computed tomography (4DCT) and to compare the results with optical three-dimensional motion capture. During active elevation, bilateral shoulders of 10 healthy volunteers were tracked using 4DCT and motion capture. The scapulothoracic and glenohumeral rotations and the scapulohumeral rhythm (SHR) at each position were calculated, and the differences between 4DCT and motion capture were compared. During 10-140° of humerothoracic elevation, the scapulothoracic joint showed upward rotation, internal rotation, and posterior tilting, and the glenohumeral joint showed elevation, external rotation, and anterior plane of elevation in both analyses. In scapulothoracic rotations, the mean differences between the two analyses were -2.6° in upward rotation, 13.9° in internal rotation, and 6.4° in posterior tilting, and became significant with humerothoracic elevation ≥110° in upward rotation, ≥50° in internal rotation, and ≥100° in posterior tilting. In glenohumeral rotations, the mean differences were 3.7° in elevation, 9.1° in internal rotation, and -8.8° in anterior plane of elevation, and became significant with humerothoracic elevation ≥110° in elevation, ≥90° in internal rotation, and ≥100° in anterior plane of elevation. The mean overall SHRs were 1.8 in 4DCT and 2.4 in motion capture, and the differences became significant with humerothoracic elevation ≥100°. The 4DCT analysis of in vivo shoulder kinematics using upright computed tomography scanner is feasible, but the values were different from those by skin-based analysis at the elevated arm 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.

Comparison of inspiratory and expiratory airway volumes and luminal areas among standing, sitting, and supine positions using upright and conventional CT

Upright computed tomography (CT) provides physiologically relevant images of daily life postures (sitting and standing). The volume of the human airway in sitting or standing positions remains unclear, and no clinical study to date has compared the inspiratory and expiratory airway volumes and luminal areas among standing, sitting, and supine positions. In this prospective study, 100 asymptomatic volunteers underwent both upright (sitting and standing positions) and conventional (supine position) CT during inspiration and expiration breath-holds and the pulmonary function test (PFT) within 2 h of CT. We compared the inspiratory/expiratory airway volumes and luminal areas on CT among the three positions and evaluated the correlation between airway volumes in each position on CT and PFT measurements. The inspiratory and expiratory airway volumes were significantly higher in the sitting and standing positions than in the supine position (inspiratory, 4.6% and 2.5% increase, respectively; expiratory, 14.9% and 13.4% increase, respectively; all P < 0.001). The inspiratory and expiratory luminal areas of the trachea, bilateral main bronchi, and average third-generation airway were significantly higher in the sitting and standing positions than in the supine position (inspiratory, 4.2‒10.3% increases, all P < 0.001; expiratory, 6.4‒12.8% increases, all P < 0.0001). These results could provide important clues regarding the pathogenesis of orthopnea. Spearman's correlation coefficients between the inspiratory airway volume on CT and forced vital capacity and forced expiratory volume in 1 s on PFT were numerically higher in the standing position than in the supine position (0.673 vs. 0.659 and 0.669 vs. 0.643, respectively); however, no statistically significant differences were found. Thus, the airway volumes on upright and conventional supine CT were moderately correlated with the PFT measurements.

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.

Differences in lung and lobe volumes between supine and upright computed tomography in patients with idiopathic lung fibrosis

No clinical study has compared lung or lobe volumes on computed tomography (CT) between the supine and standing positions in patients with idiopathic lung fibrosis (IPF). This study aimed to compare lung and lobe volumes between the supine and standing positions and evaluate the correlations between the supine/standing lung volumes on CT and pulmonary function in patients with IPF. Twenty-three patients with IPF underwent a pulmonary function test and both low-dose conventional (supine position) and upright CT (standing position) during inspiration breath-holds. The volumes of the total lungs and lobes were larger in the standing than in the supine position in patients with IPF (all p < 0.05). Spearman's correlation coefficients between total lung volumes on chest CT in supine/standing positions and vital capacity (VC) or forced VC (FVC) were 0.61/0.79 or 0.64/0.80, respectively. CT-based volumes on upright CT were better correlated with VC and FVC than those on supine CT. Lung and lobe volumes in the standing position may be useful biomarkers to assess disease severity or therapeutic effect in patients with IPF.

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.

Cranial defect and pneumocephalus are associated with significant postneurosurgical positional brain shift: evaluation using upright computed tomography

Only few studies have assessed brain shift caused by positional change. This study aimed to identify factors correlated with a large postneurosurgical positional brain shift (PBS). Sixty-seven patients who underwent neurosurgical procedures had upright computed tomography (CT) scan using settings similar to those of conventional supine CT. The presence of a clinically significant PBS, defined as a brain shift of ≥ 5 mm caused by positional change, was evaluated. The clinical and radiological findings were investigated to identify factors associated with a larger PBS. As a result, twenty-one patients had a clinically significant PBS. The univariate analysis showed that supratentorial lesion location, intra-axial lesion type, craniectomy procedure, and residual intracranial air were the predictors of PBS. Based on the multivariate analysis, craniectomy procedure (p < 0.001) and residual intracranial air volume (p = 0.004) were the predictors of PBS. In a sub-analysis of post-craniectomy patients, PBS was larger in patients with supratentorial craniectomy site and parenchymal brain injury. A large craniectomy area and long interval from craniectomy were correlated with the extent of PBS. In conclusion, patients who undergo craniectomy and those with residual intracranial air can present with a large PBS. In post-craniectomy patients, the predisposing factors of a large PBS are supratentorial craniectomy, presence of parenchymal injury, large skull defect area, and long interval from craniectomy. These findings can contribute to safe mobilization among postneurosurgical patients and the risk assessment of sinking skin flap syndrome.

Three-dimensional alignment of the upper extremity in the standing neutral position in healthy subjects

Background

Though alignment of the spine and lower extremities in the standing neutral position has been evaluated, a few studies evaluating the alignment of the upper extremities have also been made. This study assessed the normal alignment of the upper extremities in the standing neutral position and clarified the three-dimensional angular rotations of the upper extremity joints.

Methods

Computed tomography (CT) images of 158 upper extremities from 79 healthy volunteers were prospectively acquired in the standing neutral position using an upright CT scanner. Three-dimensional coordinate systems of the thorax, scapula, humerus, and forearm were designated, and three-dimensional angular rotations of the scapulothoracic, glenohumeral, and elbow joints were calculated.

Results

The median angle of the scapulothoracic joint was 9.2° (interquartile range [IQR], 5.2°–12.5°) of upward rotation, 29.0° (IQR, 24.9°–33.3°) of internal rotation, and 7.9° (IQR, 4.3°–11.8°) of anterior tilt. The median angle of the glenohumeral joint was 4.5° (IQR, 0.9°–7.8°) of abduction, 9.0° (IQR, 2.2°–19.0°) of internal rotation, and 0.3° (IQR, − 2.6°–3.1°) of extension. The median angle of the elbow joint was 9.8° (IQR, 6.9°–12.4°) of valgus, 90.2° (IQR, 79.6°–99.4°) of pronation, and 15.5° (IQR, 13.2°–18.1°) of flexion. Correlations in angular rotation values were found between the right and left upper extremities and between joints.

Conclusions

This study clarified the three-dimensional angular rotation of upper extremity joints in the standing neutral position using an upright CT scanner. Our results may provide important insights for the functional evaluation of upper extremity alignment.

Interaction of Eating Status and Dietary Variety on Incident Functional Disability among Older Japanese Adults

OBJECTIVES

To examine whether eating status and dietary variety were associated with functional disability during a 5-year follow-up analysis of older adults living in a Japanese metropolitan area.

DESIGN

A 5-year follow-up study.

SETTING

Ota City, Tokyo, Japan.

PARTICIPANTS

A total of 10,308 community-dwelling non-disabled adults aged 65-84 years.

MEASUREMENTS

Eating status was assessed using a self-reported questionnaire. Dietary variety was assessed using the dietary variety score (DVS). Based on the responses, participants were classified according to eating alone or together and DVS categories (low: 0-3; high: 4-10). Functional disability incidence was prospectively identified using the long-term care insurance system's nationally unified database. Multilevel survival analyses calculated the adjusted hazard ratio (HR) and 95% confidence interval (CI) for incident functional disability.

RESULTS

During a 5-year follow-up, 1,991 (19.3%) individuals had functional disabilities. Eating status or DVS were not independently associated with incident functional disability. However, interaction terms between eating status and DVS were associated with functional disability; HR (95% CI) for eating together and low DVS was 1.00 (0.90-1.11), eating alone and high DVS was 0.95 (0.77-1.17), and eating alone and low DVS was 1.20 (1.02-1.42), compared to those with eating together and high DVS.

CONCLUSION

Older adults should avoid eating alone or increase dietary variety to prevent functional disability. This can be ensured by providing an environment of eating together or food provision services for eating a variety of foods in the community.

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.

Analysis of Lap Belt Fit to Human Subjects using CT Images

In vehicle collisions, the lap belt should engage the anterior superior iliac spine (ASIS). In this study, threedimensional (3D) shapes of bones and soft tissues around the pelvis were acquired using a computed tomography (CT) scan of 10 male and 10 female participants wearing a lap belt. Standing, upright sitting, and reclined postures were scanned using an upright CT and a supine CT scan system. In the upright sitting posture, the thigh height was larger with a higher BMI while the ASIS height did not change significantly with BMI. As a result, the height of the ASIS relative to the thigh (ASIS-thigh height) became smaller as the BMI increased. Because the thigh height of females was smaller than that of males, the ASIS-thigh height was larger for females than for males. As the ASIS-thigh height was larger, the overlap of the lap belt with the ASIS increased. Thus, the lap belt overlapped more with the ASIS for the females than for the males. The abdomen outer shape is characterized by the trouser cord formed valley, the torso/thigh junction, and the anterior convexity formed between them depending on the adipose tissues. The abdomen outer shapes changed from the standing, the reclined posture to the upright sitting posture. In the reclined sitting posture, the lap belt is positioned upward and rearward relative to the ASIS, and the overlap of the lap belt with the ASIS was smaller compared to the upright posture.

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04786-5.

Drug repositioning of antipsychotic drugs for cisplatin-induced pica behavior in mice

We aimed to clarify whether various antipsychotics ameliorate cisplatin-induced pica behavior in mice using a drug repositioning approach. Mice were administered cisplatin (12.5 mg/kg, i.p.) with or without olanzapine (1 mg/kg, i.p.), asenapine (4 mg/kg, i.p.), mirtazapine (5 mg/kg, i.p.) or standard three-drug antiemetics (granisetron [0.5 mg/kg, i.p.], fosaprepitant [25 mg/kg, i.p.], and dexamethasone [3 mg/kg, i.p.]). Kaolin, food, and water intake, and spontaneous motor activity on the day before and seven consecutive days after the cisplatin administration were measured using a telemetry system. At the primary endpoint, kaolin intake was significantly higher at day three in the cisplatin group than in the pre-treatment and saline groups ( p < 0.05). Additionally, kaolin intake was not significantly higher in cisplatin with olanzapine, asenapine, and mirtazapine groups for seven days than in the pre-treatment group. At the secondary endpoint, cisplatin decreased the food and water intake, and spontaneous motor activity in a time-dependent manner. Three antipsychotics failed to improve the cisplatin-induced decrease in food and water intake, and spontaneous motor activity. The findings suggest that prophylactic administration of antipsychotics besides olanzapine may improve cisplatin-induced nausea and vomiting in a delayed phase and de-escalate standard 3-drug antiemetics.

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.

Saphenous vein valve assessment utilizing upright CT to potentially improve graft assessment for bypass surgery

Saphenous veins (SVs) are frequently employed as bypass grafts. The SV graft failure is predominantly seen at the valve site. Avoiding valves during vein harvest would help reduce graft failure. We endeavored to detect SV valves, tributaries, and vessel size employing upright computed tomography (CT) for the raw cadaver venous samples and in healthy volunteers. Five cadaver legs were scanned. Anatomical analysis showed 3.0 (IQR: 2.0-3.0) valves and 13.50 (IQR: 10.00-16.25) tributaries. The upright CT completely detected, compared to 2.0 (IQR: 1.5-2.5, p = 0.06) valves and 9.5 (IQR: 7.5-13.0, p = 0.13) tributaries by supine CT. From a total of 190 volunteers, 138 (men:75, women:63) were included. The number of valves from the SF junction to 35 cm were significantly higher in upright CT than in supine CT bilaterally [upright vs. supine, Right: 4 (IQR: 3-5) vs. 2 (IQR:1-2), p < 0.0001, Left: 4 (IQR: 3-5) vs. 2 (IQR: 1-2), p < 0.0001]. The number of tributaries and vessel areas per leg were also higher for upright compared with supine CT. Upright CT enables non-invasive detection of SV valves, tributaries, and vessel size. Although not tested here, it is expected that upright CT may potentially improve graft assessment for bypass surgery.

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.

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 .

Association between Oral Frailty and Dietary Variety among Community-Dwelling Older Persons: A Cross-Sectional Study

OBJECTIVE

To examine the association between the severity of oral frailty (OF), which is one of the comprehensive oral functions evaluated, and dietary variety in community-dwelling older persons.

DESIGN

Cross-sectional study.

SETTING

Community-based.

PARTICIPANTS

A total of 769 community-dwelling older persons aged 65 and over.

INTERVENTIONS

We examined basic demographic information, functional status, cognitive status, depressive symptoms, medical history, and oral functions of the participants.

MEASUREMENTS

OF was defined by 1-2 and 3 or more of 6 items of oral function evaluation in the pre-oral frailty and oral frailty groups, respectively. Dietary variety was assessed using the dietary variety score (DVS). The participants were categorized into 3 groups for evaluation: those with a low score (0-2), medium score (3-5), and high score (≥6). Ordinal logistic regression analysis was performed to examine the association between OF and DVS.

RESULTS

The rate of OF in the participants was 21.6%, and its severity was significantly associated with DVS after adjusting for potential confounders (Pre-OF; adjusted odds ratio [OR] = 1.687, 95% confidence interval [CI] = 1.219-2.335, OF; adjusted OR = 2.857, 95% CI = 1.489-5.484).

CONCLUSION

The severity of OF was significantly associated with DVS in community-dwelling older persons. This suggests that DVS may be useful in understanding the effects of OF on the nutritional status. Further longitudinal studies are needed to elucidate the association between OF and DVS.

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.

Long-term prognosis in patients with non-type 1 Brugada ECG: results from a large Japanese cohort of Brugada syndrome

Background

Most recent consensus conference report recommends Brugada syndrome (BrS) is diagnosed in patients with ST segment elevation with spontaneous, drug-induced or fever-induced type 1 morphology. Prognosis in patients with type 2 or 3 ECG without drug-induced or fever-induced type 1 ECG is still unknown.

Purpose

To evaluate a long-term prognosis in patients with non-type 1 Brugada ECG in a large Japanese cohort of BrS (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]).

Methods

From 528 patients in J-IVFS, a total of 28 consecutive non-type 1 patients (54±14 years, all male, previous sustained ventricular tachyarrhythmias (VTs) 1, syncope 11, asymptomatic 16) were enrolled. Cardiac events (CI: sudden cardiac death or VTs) during the follow-up period were evaluated, and risk factors for the cardiac events were assessed.

Results

During a mean follow-up period of 111±91 months (median 134 months), 4 patients experienced cardiac events (1.5%/yr), who all had received implantable cardioverter defibrillator implantation. There was no statistically significant clinical risk factor for cardiac events. However, the incidences of cardiac events tended to be higher in symptomatic patients (CI: 25.0, non-CI: 6.3%, p=0.17), those with wide QRS duration &gt;90 msec in lead V2 (CI: 30.0, non-CI: 6.3%, p=0.11), and those with inducible VTs (CI: 21.1, non-CI: 0%, p=0.20), as determined by the Kaplan-Meier method. The annual incidences of cardiac events in patients with symptom, wide QRS duration &gt;90msec in lead V2, or inducible VTs were 2.8, 3.5, and 2.0%/yr, respectively. The incidences of cardiac events were significantly higher in patients with all these 3 factors (9.9%/yr) than those without (p=0.01).

Conclusions

Our large-scaled multicentre study revealed long-term prognosis in patients with non-type 1 Brugada ECG. The combination of symptom, wide QRS duration in lead V2, and inducible VTs may be useful to evaluate risk for cardiac events. The patients with all these parameters showed high risk for cardiac events and need to be carefully followed.

Funding Acknowledgement

Type of funding source: None

The safety of catheter ablation of atrial fibrillation in elderly patients -analysis of the nationwide database in Japan, JROAD-DPC-

Background

“Age” is one of the major concerns and determinants of the indications for catheter ablation (CA) of atrial fibrillation (AF). There are little safety data on CA of AF according to the age. This study aimed to assess the safety of CA in elderly patients undergoing CA of AF.

Methods and results

We investigated the complication rate of CA of AF for the different age groups (&lt;60 years, 60–65, 65–70, 70–75, 75–80, 80–85, and ≥85) by a nationwide database (Japanese Registry Of All cardiac and vascular Diseases [JROAD]-DPC). The JROAD-DPC included 73,296 patients (65±11 years, 52,883 men) who underwent CA of AF from 516 hospitals in Japan. Aged patients had more comorbidities and a significantly increased CHADS2 score and higher rate of female according to a higher age. The overall complication rate was 2.6% and in-hospital mortality was 0.05%. By comparing each age group, complications occurred more frequently in higher aged groups. A multivariate adjusted hazard ratio revealed an increased age was independently and significantly associated with the overall complications (odds ratio was 1.25, 1.35, 1.72, 1.86, 2.76 and 3.13 respectively; reference &lt;60 years).

Conclusions

The frequency of complications was significantly higher according to a higher age. We should take note of the indications and procedure for CA of AF in aged patients.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Intramural Research Fund 17 (Kusano) for Cardiovascular Diseases of the National Cerebral and Cardiovascular Center

Posture-induced changes in the vessels of the head and neck: evaluation using conventional supine CT and upright CT

Since the venous system is affected by gravity, upright computed tomography (CT) in addition to conventional supine CT has great potential for evaluating postural changes in the venous system. We evaluated the morphological differences in the head and neck vessels by performing a contrast CT study in both the supine and the sitting positions. In this study, the 20 included participants (10 men and 10 women) were healthy adults aged 30 to 55 years. The cross-sectional area of the cervical vessels, craniocervical junction veins, and intracranial vessels were obtained quantitatively. Venous sinuses and venous plexuses that were difficult to measure were evaluated qualitatively. The average change in areas from a supine to an upright posture was - 77.87 ± 15.99% (P < 0.0001) in the right internal jugular vein (IJV), - 69.42 ± 23.15% (P < 0.0001) in the left IJV, - 61.52 ± 12.81% (P < 0.0001) in the right external jugular vein (EJV), and - 58.91 ± 17.37% (P < 0.0001) in the left EJV. In contrast, the change in the anterior condylar vein (ACV) from a supine to an upright posture was approximately + 144% (P < 0.005) on the right side and + 110% (P < 0.05) on the left side. In addition, according to the qualitative analysis, the posterior venous structures including the anterior condylar confluence (ACC) of the craniocervical junction became more prominent in an upright posture. Despite these changes, the intracranial vessels showed almost no change between postures. From a supine to an upright position, the IJVs and EJVs above the heart collapsed, and venous channels including the ACCs and ACVs opened, switching the main cerebral venous drainage from the IJVs to the vertebral venous system. Upright head CT angiography can be useful for investigating physiological and pathophysiological hemodynamics of the venous system accompanying postural changes.

Orthostatic Enlargement of a Supracerebellar Arachnoid Cyst With Cerebellar Descent Visualized by Upright Computed Tomography

BACKGROUND

Posterior fossa arachnoid cysts are often asymptomatic, but can rarely cause postural headache, the mechanism of which remains unknown.

CASE DESCRIPTION

We present a 40-year-old woman with an asymptomatic supracerebellar arachnoid cyst. Upright computed tomography (CT) showed enlargement of the arachnoid cyst and caudal descent of the cerebellum compared with supine CT with narrowing of the craniocervical junction cerebrospinal fluid space.

CONCLUSIONS

This finding aids in understanding the association of posterior fossa arachnoid cysts with orthostatic headache. Clinicians should be aware of possible posture-related changes in intracranial structures.

Evaluation of three-dimensional acromiohumeral distance in the standing position and comparison with its conventional measuring methods

Background

Narrowing of the acromiohumeral distance (AHD) implies a rotator cuff tear. However, conventional AHD measurements using two-dimensional (2D) imaging or with the patient in the supine position might differ from that while standing during daily activity. This study aimed to evaluate the three-dimensional (3D) actual distance between the acromion and humeral head in the standing position and compare the AHD values with those obtained using conventional measuring methods.

Methods

Computed tomography (CT) images of 166 shoulders from 83 healthy volunteers (31 male and 52 female; mean age 40.1 ± 5.8 years; age range, 30–49 years) were prospectively acquired in the supine and standing positions using conventional and upright CT scanners, respectively. The minimum distance between the acromion and humeral head on the 3D surface models was considered as the 3D AHD. We measured the 2D AHD on anteroposterior digitally reconstructed radiographs. The AHD values were compared between the supine and standing positions and between the 2D and 3D measurements.

Results

The mean values of 2D AHD were 8.8 ± 1.3 mm (range, 5.9–15.4 mm) in the standing position and 8.1 ± 1.2 mm (range, 5.3–14.3 mm) in the supine position. The mean values of 3D AHD were 7.3 ± 1.4 mm (range, 4.7–14.0 mm) in the standing position and 6.6 ± 1.2 mm (range, 4.4–13.7 mm) in the supine position. The values of 3D AHD were significantly lower than those of 2D AHDs in both the standing and supine positions (P < 0.001). The values of 2D and 3D AHDs were significantly lower in the supine position than in the standing position (P < 0.001).

Conclusions

This study evaluated the 3D AHD of normal shoulders in the standing position using an upright CT scanner. The present results indicated that assessments in the supine position can underestimate the value of the AHD compared with those made in the standing position and that assessments using 2D analysis can overestimate the value.

Three-dimensional alignment changes of the shoulder girdle between the supine and standing positions

Background

Although humans spend most of their day in a standing or sitting position, it is difficult to accurately evaluate the alignment of the shoulder girdle during daily activity, and its alignment changes between positions. The purpose of this study was to evaluate the 3-dimensional alignment of the shoulder girdle in the supine and standing positions by computed tomography (CT) and to assess the alignment changes of the shoulder girdle between these two positions.

Methods

CT scans of both shoulders of 100 healthy volunteers were prospectively taken in both supine and standing positions on the same day. The local 3-dimensional coordinate systems of the thorax, clavicle, and scapula were defined from the specific bony landmarks, and 3-dimensional angular rotations and positions of the clavicle and scapula were calculated. Differences in rotations and positions of the clavicle and scapula were evaluated between the supine and standing positions.

Results

Compared with the supine position, the clavicle showed significantly less elevation and greater retraction, and the scapula showed significantly less upward rotation, anterior tilting, and internal rotation in the standing position. Compared with the supine position, the clavicle center was located more inferiorly, posteriorly, and laterally, and the scapula center was located more inferiorly, posteriorly, and medially in the standing position.

Conclusions

The present study showed that angular rotations and positions of the clavicle and scapula change significantly with position due to the effect of gravity.

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.

High Pressure Quenched Glasses: unique structures and properties

Zr-based metallic glasses are prepared by quenching supercooled liquid under pressure. These glasses are stable in ambient conditions after decompression. The High Pressure Quenched glasses have a distinct structure and properties. The pair distribution function shows redistribution of the Zr-Zr interatomic distances and their shift towards smaller values. These glasses exhibit higher density, hardness, elastic modulus, and yield stress. Upon heating at ambient pressure, they show volume expansion and distinct relaxation behavior, reaching an equilibrated state above the glass transition. These experimental results are consistent with an idea of pressure-induced low to high density liquid transition in the supercooled melt.

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.

Temporal trends in the prevalence of albuminuria and reduced eGFR in Japanese patients with type 2 diabetes

Changes over time have been shown in renal manifestations in individuals with diabetes in the United States; however, whether the trends are shared across ethnicities is unknown. We conducted this single-center serial cross-sectional study to determine temporal changes in albuminuria and reduced kidney function in Japanese patients with type 2 diabetes. This study included adult Japanese patients with type 2 diabetes who first visited our institute between 2004 and 2013. Temporal changes during the 10 years in the frequency of albuminuria ( ≥ 30 mg/g creatinine) and reduced eGFR ( < 60 mL/min/1.73 m²) were analyzed using the univariate and multivariate logistic regression analyses and Granger causality test. 5331 Japanese patients with type 2 diabetes, 1892 women and 3439 men, with the mean age of 56 ± 13 years, were studied. There was no change in the prevalence of albuminuria in the univariate analysis; however, a significantly decreasing trend was observed after adjustment for several covariates. On the other hand, patients with reduced eGFR significantly increased over time, although the statistical significance disappeared after adjustment for the covariates, including levels of serum uric acid and hemoglobin and use of renin-angiotensin inhibitors. The Granger causality test showed that time series for use of RAS inhibitors and BMI had a causative role in time series for reduced eGFR. In conclusion, prevalence of albuminuria decreased and that of reduced eGFR remained stable after adjustment for clinical characteristics in Japanese patients with type 2 diabetes during the last decade.

A multicenter, randomized, rater-blinded, parallel-group, phase 3 study to compare the efficacy, safety, and immunogenicity of biosimilar RGB-10 and reference once-daily teriparatide in patients with osteoporosis

The efficacy and safety of RGB-10 and reference teriparatide were evaluated in a randomized 52-week study in 250 patients with osteoporosis at high risk of fracture. RGB-10 was equivalent to reference teriparatide in efficacy and had a comparable safety profile.

INTRODUCTION

RGB-10 is the first biosimilar teriparatide authorized in the European Union. This multicenter, randomized, rater-blinded, parallel-group phase 3 study evaluated equivalence in efficacy and compared safety between RGB-10 and reference teriparatide in patients with osteoporosis at high risk of fracture for registration in Japan.

METHODS

Ambulatory postmenopausal women and men (≥ 55 years of age) with osteoporosis at high risk of fracture were randomized 1:1 to receive either RGB-10 or reference teriparatide 20 μg once daily via subcutaneous self-injection for 52 weeks. The primary efficacy endpoint was the percent change from baseline to 52 weeks in lumbar spine (L2-L4) bone mineral density (BMD). Safety outcomes and immunogenicity were also assessed.

RESULTS

In total, 250 patients (125 in each group) were randomized. The percent change from baseline to 52 weeks in lumbar spine (L2-L4) BMD (mean ± standard deviation) was 8.94% ± 6.19% in the RGB-10 group and 9.65% ± 6.22% in the reference teriparatide group. The estimated between-group difference (95% confidence interval) was - 0.65% (- 2.17% to - 0.87%) within the pre-specified equivalence margin (± 2.8%), which indicates equivalence in efficacy between the two groups. Changes in BMD at lumbar spine (L1-L4), femoral neck, and total hip and serum procollagen type I amino-terminal propeptide were also similar between the groups. Safety profiles, including immunogenicity, were comparable.

CONCLUSIONS

The therapeutic equivalence of RGB-10 to reference teriparatide was demonstrated. RGB-10 had comparable safety profile to that of reference teriparatide.

P5029Inducibility of ventricular tachyarrhythmias by up to two extrastimuli does not predict future cardiac events in asymptomatic Brugada patients: results from long-term follow-up

Background

Most recent consensus conference report recommends Implantable Cardioverter Defibrillator (ICD) implantation for asymptomatic Brugada patients with spontaneous or fever-induced type-1 ECG (A-BrS) and inducible ventricular tachyarrhythmias (VTs) by up to two extrastimuli as class IIb indication. However, the validity of the inducible VTs by up to two extrastimuli in A-BrS is still unknown.

Purpose

To evaluate the validity of the inducibility by up to two extrastimuli in A-BrS in a large Japanese cohort of BrS (The Japan Idiopathic Ventricular Fibrillation Study [J-IVFS]).

Methods

A total of 193 consecutive A-BrS patients performed programmed electrical stimulation (PES) with non-aggressive uniform protocol (mean age 50±13 years, 180 males) were enrolled. PES protocol was using 2 basic pacing cycles and the order of introduction of up to 2 ventricular extra-stimuli from right ventricular apex [RVA] first, then right ventricular outflow tract [RVOT], 3 ventricular extra-stimuli from RVA then RVOT down to the minimum of 200ms. Clinical outcomes during the follow-up period were compared between A-BrS patients with and without inducible VTs by up to two extrastimuli.

Results

Thirty-five A-BrS (18%) had inducible VTs by up to two extrastimuli. During a mean follow-up period of 101±48 months, 7 A-BrS experienced cardiac events (sudden cardiac death [SCD] or VTs, 0.4%/yr). None of the 7 A-BrS had inducible VTs by up to two extrastimuli. The incidences of cardiac events tended to be higher in A-BrS without inducible VTs by up to two extrastimuli than in those with inducible VTs (p=0.10), as determined by the Kaplan-Meier method. In the A-BrS, the annual incidences of cardiac events in A-BrS with family history of SCD, inferolateral J wave, wide QRS duration >90msec in lead V2, or inducible VT/VF by 3 extrastimuli were 0.7, 0.7, 0.6, and 0.3%/yr, respectively.

Conclusions

Our large-scaled multicentre study with long-term follow-up revealed the inducibility of ventricular tachyarrhythmias by up to two extrastimuli does not predict future cardiac events in A-BrS, even using non-aggressive uniform protocol. Rather, other parameters such as family history of SCD or inferolateral J wave might be helpful for risk assessment in A-BrS.

Benign hilar bile duct strictures resected as perihilar cholangiocarcinoma

BACKGROUND

Differentiation between perihilar cholangiocarcinoma (PHCC) and benign strictures is frequently difficult. The aim of this study was to investigate the incidence and long-term outcome of patients with tumours resected because of suspicion of PHCC, which ultimately turned out to be benign (malignancy masquerade).

METHODS

Patients who underwent surgical resection with a diagnosis of PHCC between 2001 and 2016 were reviewed retrospectively.

RESULTS

Among 707 consecutive patients, 685 had PHCC and the remaining 22 (3·1 per cent) had benign biliary stricture. All patients with benign disease underwent major hepatectomy, with no deaths. Preoperative histological assessment using bile duct biopsy or aspiration cytology had a high specificity (90 per cent), low sensitivity (62 per cent) and unsatisfactory accuracy (63 per cent). Despite the increasing use of histological assessment, the incidence of benign strictures resected did not decrease over time, being 0·9 per cent in 2001-2004, 4·0 per cent in 2005-2008, 3·8 per cent in 2009-2012 and 2·9 per cent in 2013-2016. The final pathology of benign strictures included IgG4-related sclerosing cholangitis (9 patients), hepatolithiasis (4), granulomatous cholangitis (3), non-specific chronic cholangitis (3), benign strictures after cholecystectomy (2), and a benign stricture possibly caused by parasitic infection (1). The 10-year overall survival rate for the 22 patients with benign stricture was 87 per cent, without recurrence of biliary stricture.

CONCLUSION

The incidence of benign strictures resected as PHCC as a proportion of all resections was relatively low, at 3·1 per cent. Currently, unnecessary surgery for suspected PHCC is unavoidable.

Clinical value of additional resection of a margin-positive distal bile duct in perihilar cholangiocarcinoma

Background

Little is known about the effect of additional resection for a frozen-section-positive distal bile duct margin (DM) in perihilar cholangiocarcinoma.

Methods

Patients who underwent surgical resection for perihilar cholangiocarcinoma between 2001 and 2015 were analysed retrospectively, focusing on the DM.

Results

Of 558 consecutive patients who underwent frozen-section examination for a DM, 74 (13·3 per cent) had a frozen-section-positive DM with invasive cancer or carcinoma in situ. Eventually, 53 patients underwent additional resection (bile duct resection in 44 and pancreatoduodenectomy in 9), whereas the remaining 21 patients did not. Ultimately, R0 resection was achieved in 30 of the 53 patients (57 per cent). No patient who underwent additional resection died from surgical complications. The 44 patients with additional bile duct resection had a 5-year overall survival rate of 31 per cent. Overall survival of the nine patients who had pancreatoduodenectomy was better, with a 10-year rate of 67 per cent. Survival of the 21 patients without additional resection was dismal: all died within 5 years. Multivariable analyses identified nodal status and additional resection as independent prognostic factors (lymph node metastasis: hazard ratio (HR) 2·26, 95 per cent c.i. 1·26 to 4·07; bile duct resection versus no additional resection: HR 0·32, 0·17 to 0·60; pancreatoduodenectomy versus no additional resection: HR 0·08, 0·02 to 0·29).

Conclusion

Additional resection for frozen-section-positive DM in perihilar cholangiocarcinoma frequently yields R0 margins. It offers a better chance of long-term survival, and thus should be performed in carefully selected patients.

Major hepatectomy with or without pancreatoduodenectomy for advanced gallbladder cancer

BACKGROUND

The indications for major hepatectomy for gallbladder cancer either with or without pancreatoduodenectomy remain controversial. The clinical value of these extended procedures was evaluated in this study.

METHODS

Patients who underwent major hepatectomy for gallbladder cancer between 1996 and 2016 were identified from a prospectively compiled database. Postoperative outcomes and overall survival were compared between patients undergoing major hepatectomy alone or combined with pancreatoduodenectomy (HPD).

RESULTS

Seventy-nine patients underwent major hepatectomy alone and 38 patients had HPD. The patients who underwent HPD were more likely to have T4 disease (P < 0·001), nodal metastasis (P = 0·015) and periaortic nodal metastasis (P = 0·006), but were less likely to receive adjuvant therapy (P = 0·006). HPD was associated with a high incidence of grade III or higher complications (P = 0·002) and death (P = 0·037). Overall survival was longer in patients who underwent major hepatectomy alone than in patients who underwent HPD (median survival time 32 versus 10 months; P < 0·001). In multivariable analysis, surgery in the early period (1996-2006) (P = 0·002), pathological T4 disease (P = 0·005) and distant metastasis (P < 0·001) were associated with shorter overall survival, and cystic duct tumour (P = 0·002) with longer overall survival.

CONCLUSION

Major hepatectomy alone for gallbladder cancer contributes to favourable overall survival with low morbidity and mortality, whereas HPD is associated with poor overall survival and high morbidity and mortality rates. HPD may eradicate locally spreading gallbladder cancer; however, the indication for the procedure is questioned from an oncological viewpoint.