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Rib fractures are a common and serious outcome of blunt thoracic trauma and their likelihood is greater in older individuals. Osteoporotic bone loss is a well-documented aging phenomenon with sex-specific characteristics, but within rib bones, neither baseline maps of regional thickness nor the rates of bone thinning with age have been quantified across whole ribs. This study presents such data from 4014 ribs of 240 adult subjects aged 20-90. A validated cortical bone mapping technique was applied to clinical computed tomography scans to obtain local rib cortical bone thickness measurements over the surfaces of ribs 2 through 11. Regression models to age and sex gave rates of cortex thinning in local zones and aggregated across whole ribs. The statistical parametric mapping provided these relationships regionally as a function of rib surface location. All models showed significant reductions in bone thickness with age (p 0.01). Average whole-rib thinning occurred at between 0.011 to 0.032 mm/decade (males) and 0.035 to 0.043 mm/decade (females), with sex and age accounting for up to 37% of population variability (R

Lung volume reduction surgery continues to have a high morbidity despite National Emphysema Treatment Trial selection criteria. This study evaluated the association between analytic morphomics on chest computed tomography scans and outcomes after lung volume reduction surgery. In a retrospective review of 85 lung volume reduction surgery patients from 1998-2013, dorsal muscle group area, subcutaneous and visceral fat area, and bone mineral density were assessed using analytic morphomics. Lung density was divided into five levels of increasing density (Lung density 1, emphysema; 2, normal lung; 4-5, scarring). Outcomes including survival, hospital length of stay, readmission at 30 days, and pulmonary complications were analyzed using univariate and multivariable techniques. Pulmonary complications developed in 27.1% (23/85). Mortality at 90 days was 9.4% (8/85). On multivariable analysis, lower bone mineral density (Odds ratio 0.61; 95% confidence interval 0.39-0.95) was associated with decreased survival, longer length of stay (0.83; 0.77-0.89), and readmissions (0.39; 0.15-1.00). Higher lung density 5:lung density 2 volume (1.84; 1.05-3.23), possibly due to scarring, was associated with pulmonary complications and longer length of stay (1.32; 1.23-1.41) while lower subcutaneous fat area:height was associated with readmissions which may reflect decreased metabolic reserve (0.35; 0.13-0.93). Patients with signs of frailty including lower bone mineral density may be at increased risk of adverse outcomes including decreased survival after lung volume reduction surgery. The results of this hypothesis-generating study will need to be confirmed in larger, multicenter trials to determine whether analytic morphomics can improve risk stratification and patient selection.

Objective To morphometrically measure to muscle mass which may reflect physical components of frailty. Hence, we evaluated the association between L4 total psoas area (TPA) and operative outcome after radical cystectomy (RC) for bladder cancer. Methods In a retrospective single-center study, bladder cancer patients who underwent RC and urinary diversion between 2007 and 2012 were enrolled. TPA was evaluated in the cross-sectional imaging. The psoas muscles were normalized with the height. Male patients with a psoas mass index ≤7.4 cm2/m2 and female patients with a psoas mass index ≤5.2 cm2/m2 were classified as sarcopenic. Outcome measures were 30- and 90-day readmission and complications, and survival. Multivariable logistic and Cox proportional-hazards regression models were used to determine relevant predictors. Results The median age of the 441 participants and follow up time was 68 years (IQR 59-75) and 1.2 years (IQR 0.5-1.9), respectively. One hundred forty-three patients (32.4%) were sarcopenic. The 30-day readmission and the complication rates were 13.8% and 44.7%, respectively. The 90-day readmission and complication rates were 23.9% and 53.1%, respectively. The 1-year mortality rate was 11.6% (95%CI 8.7-15.4). Multivariable logistic regression analysis revealed an association between increased TPA and lower odds of 30-day complications after RC (OR 0.95, 95%CI 0.92-0.99, P = .02); similarly, an increase in TPA was of prognostic value, although not statistically significant in the multivariable model (P = .05) once adjusting for other patient factors. Conclusion Sarcopenia predicted early complications and showed an informative trend for overall survival after RC, and thus may inform models predicting postsurgical outcomes.

The key landmark for tip position of a central venous catheter (CVC) is the SVC-RA junction. In adults, localization of the SVC-RA junction may be assessed as a function of vertebral body units (VBU) below the carina during CVC placement. We investigated the relationship between the SVC-RA junction and the carina in children. 584 CT scans of 0–18 years were analyzed. The carina was marked automatically by software while the SVC-RA junction and vertebrae were marked manually. The SVC-RA junction to carina (JC) distance was the primary study measurement reported in both VBU and mm. The data show an average JC distance of 1.25 VBU for 0–1 year, 1.27 VBU for 1–4 years, 1.34 VBU for 4–9 years, 1.53 VBU for 9–15 years, and 1.64 VBU for 15–18 years. A positive relationship between weight and JC distance was also demonstrated. JC distance is a useful predictor of SVC-RA junction location in children. Significant relationships were shown between JC distance and both age and weight. Due to small differences between age groups, however, average JC distance for all comers (1.48 VBU, 95% CI 0.7 – 2.3) can be used for SVC-RA junction identification in CVC placement.

Finite element human body models (HBMs) are used to assess injury risk in a variety of impact scenarios. The ribs are a key structural component within the chest, so their accuracy within HBMs is vitally important for modeling human biomechanics. We assessed the geometric correspondence between the ribs defined within five widely used HBMs and measures drawn from population-wide studies of rib geometry, focusing on (1) rib global shape, (2) rib cross-sectional size and shape, and (3) rib cortical bone thickness. A parametric global shape model fitted to all HBM ribs was compared to expected rib parameters calculated for each HBM’s subject demographic using population reference data. The GHBMC M50 and THUMS M50 male HBMs showed 24% and 50% of their fitted rib shape parameters (6 parameters per each 12 ribs) falling outside 1SD from population expected values, respectively. For female models the GHBMC F05, THUMS F05, and VIVA F50 models had 21%, 26%, and 19% of their rib shape parameters falling outside 1SD, respectively. Cross-sectional areas and inertial moments obtained along the HBM ribs were compared to average ± 1SD corridors for male and female ribs drawn from reference population data. The GHBMC M50, THUMS M50, and VIVA F50 model ribs were all larger in overall cross-sectional area than their targeted average population values by 0.9SDs (average across the rib’s full length), 1.7SDs, and 1.3SDs, respectfully. When considering cortical bone cross-sectional area, the THUMS and VIVA models—which each define a constant bone thickness value across the entire rib—overestimated bone content on average by 1.1SDs and 1.2SDs, respectively. HBMs have traditionally performed poorly when predicting rib fracture onset or fracture site, and in all HBMs in this study the rib regions with the most extreme cortical bone thickness and cross-sectional area discrepancies (compared to average reference data) corresponded to regions toward the sternal end of the ribs where rib fractures most frequently occur. Results from this study highlight geometrical components of current HBM ribs that differ from the rib geometry that would be expected from within those models’ target demographics, and help researchers prioritize improvements to their biofidelity.

Sarcopenia has been shown to be an independent negative predictor in various diseases. The measurement of pre-defined criteria of skeletal muscle in patients with acute disease is usually unavailable. Therefore, we evaluate the psoas muscle area based on computed tomography (CT) imaging as an alternative for sarcopenia in an Asian trauma population. 939 trauma patients were enrolled and had CT imaging performed primarily for trauma indications. The cross-sectional area of psoas muscle at the base of the fourth lumbar vertebral was measured on these CTs. Psoas muscle index (PMI) was calculated and analyzed to determine sex-specific cut-off values to define the “extremely low psoas muscle index” (ELPMI) group. Psoas muscle index was significantly higher in males (1065.09 ± 230.51 mm2/m2 in males vs 719.57 ± 147.39 mm2/m2 in females, p

Background CT contrast media improves vessel visualization but can also confound calcification measurements. We evaluated variance in aorta attenuation from varied contrast-enhancement scans, and quantified expected plaque detection errors when thresholding for calcification. Methods We measured aorta attenuation (AoHU) in central vessel regions from 10K abdominal CT scans and report AoHU relationships to contrast phase (non-contrast, arterial, venous, delayed), demographic variables (age, sex, weight), body location, and scan slice thickness. We also report expected plaque segmentation false-negative errors (plaque pixels misidentified as non-plaque pixels) and false-positive errors (vessel pixels falsely identified as plaque), comparing a uniform thresholding approach and a dynamic approach based on local mean/SD aorta attenuation. Results Females had higher AoHU than males in contrast-enhanced scans by 65/22/20 HU for arterial/venous/delayed phases (p < 0.001) but not in non-contrast scans (p > 0.05). Weight was negatively correlated with AoHU by 2.3HU/10kg but other predictors explained only small portions of intra-cohort variance (R2 < 0.1 in contrast-enhanced scans). Average AoHU differed by contrast phase, but considerable overlap was seen between distributions. Increasing uniform plaque thresholds from 130HU to 200HU/300HU/400HU produces respective false-negative plaque content losses of 35%/60%/75% from all scans with corresponding false-positive errors in arterial-phase scans of 95%/60%/15%. Dynamic segmentation at 3SD above mean AoHU reduces false-positive errors to 0.13% and false-negative errors to 8%, 25%, and 70% in delayed, venous, and arterial scans, respectively. Conclusion CT contrast produces heterogeneous aortic enhancements not readily determined by demographic or scan protocol factors. Uniform CT thresholds for calcified plaques incur high rates of pixel classification errors in contrast-enhanced scans which can be minimized using dynamic thresholds based on local aorta attenuation. Care should be taken to address these errors and sex-based biases in baseline attenuation when designing automatic calcification detection algorithms intended for broad use in contrast-enhanced CTs.

Introduction: Cardiovascular disease remains the leading cause of death in the United States. Aortic calcification shows strong promise towards preventative screening efforts for cardiovascular risk in clinical and subclinical populations. While still relatively novel, granular distributions of aortic calcium in reference populations are absent from the literature. Methods: All participants of the Reference Analytic Morphomics Population, an approximation of vehicle occupants in the United States, with abdominal scans were considered for this analysis (n=4080). Analytic Morphomics was used to obtain vertebral-indexed anatomical measurements of the aorta and calcium characteristics (area, volume, density, and aortic wall obfuscation). Calcification was specifically identified as regions with a given morphology and pixel value three standard deviations above the defined central lumen zone. Results: Participant mean age was 33 (SD 22.6) and were mostly male (62.6%) due to the prevalence of males involved in trauma. Age and calcification distributions were right skewed among all vertebral levels and highest for the L3-L4 reference levels [~3% wall obfuscation (SD 10.5-11.3)]. Males demonstrated a progressive increase in total calcium volume from the 4 th decade of age, while females had comparatively smaller increases and a dramatic increase in total calcium after the 7 th decade. The largest increases in observed calcium volumes were observed in the 8 th decade for males (~2300 cm 3 ) and 7 th for females (~4500 cm 3 ). Conclusion: Aortic calcium prevalence was higher with reference to lower vertebral levels. Dramatic differential distributions of calcium were observed by age and sex.

Sarcopenia, visceral fat volume, and bone density have been associated with lung cancer survival. We developed a morphomic index based on computed tomographic measurements of these components, and assessed its relationship to survival after lung cancer resection.Patients who underwent lung cancer resection from 1995 to 2014 were evaluated. A morphomic index (range of 0 to 3) was developed as the sum of the scores for three body components-dorsal muscle area, vertebral trabecular bone density, and visceral fat area-measured at vertebral levels T10 to T12, with a point assigned to each component when in the lowest tercile. The relationship of the morphomic index to overall survival was assessed by the log rank test. Overall survival was assessed using Cox proportional hazards models adjusted for relevant covariates.We included 944 patients (451 women; 48%). The mean age was 66.4 ± 10.3 years. Median follow-up was 4.5 years. Median survival was associated with the morphomic index scores on univariate analysis (P.001). Morphomic index scores of 2 (P = .026) and 3 (P = .004) referenced to score 0 or 1 were independent predictors of survival on Cox regression analysis.A morphomic index is an independent predictor of survival after lung cancer resection. The index may help in calibrating patient expectations and in shared decision making regarding lung cancer surgery.

Frailty and sarcopenia are associated with mortality and poor outcomes among patients with cirrhosis. Frailty is multifactorial but due in part to sarcopenia and cognitive dysfunction. Data are limited regarding the correlation of bedside frailty and cognitive function measures with sarcopenia. To evaluate the correlations between frailty measures and muscle indices from computed tomography (CT). We prospectively enrolled 106 patients with clinically compensated cirrhosis (and no prior hepatic encephalopathy). All patients underwent CT scan and cognitive testing (via inhibitory control test, ICT), and were subject to hand grip, 30-s chair stands, mid-arm muscle area (MAMA), and a four-question algorithm based on the Sickness Impact Profile (SIP) predictive of minimal HE. We evaluated Spearman correlations between all measures as well as the sensitivity and specificity of each measure for falls. In total, 106 (35.3%) patients (55 men) had CT scans to measure skeletal muscle area and quality. Hand grip correlated strongly with skeletal muscle area (correlation coefficient 0.64, p

Background Aortic wall calcification shows strong promise as a cardiovascular risk factor. While useful for visual enhancement of vascular tissue, enhancement creates heterogeneity between scans with and without contrast. We evaluated the relationship between aortic calcification in routine abdominal computed tomography scans (CT) with and without contrast. Methods Inclusion was limited to those with abdominal CT-scans with and without contrast enhancement within 120 days. Analytic Morphomics, a semi-automated computational image processing system, was used to provide standardized, granular, anatomically indexed measurements of aortic wall calcification from abdominal CT-scans. Aortic calcification area (ACA) and aortic wall calcification percent (ACP) and were the outcomes of interest. Multiple linear regression was used to evaluate the relationship of aortic measurements. Models were further controlled for age and sex. Stratification of measurements by vertebral level was also performed. Results A positive association was observed for non-contrast calcification in ACP β 0.74 (95% CI 0.72, 0.76) and ACA β 0.44 (95% 0.43, 0.45). Stratified results demonstrated the highest coefficient of determination at L2 for percent and L3 for area models [R2 0.91 (ACP) 0.74 (ACA)]. Adjusted lumber-level associations between non-contrast and contrast measurements ranged from (β 0.69–0.82) in ACP and (β 0.37–0.54) in ACA. Conclusion A straightforward correction score for comparison of abdominal aortic calcification measurements in contrast-enhanced and non-contrast scans is discussed. Correction of aortic calcification from CT scans can reduce scan heterogeneity and will be instrumental in creating larger cardiovascular cohorts as well as cardiovascular risk surveillance programs.

Introduction: While preoperative bone health optimization is typical in the fragile population, objective assessment is limited. Among the aged, localized discordance in bone loss is prevalent and may not be assessed properly with traditional diagnostic measures. Etiology for bone loss discordance is unknown, but may be attributed to aging, disease state, habitus, or activity. This study investigated the association between body composition measures and common fragility fractures. Hypothesis: We hypothesized that each different fracture outcome would associate differently with measures of body composition. Methods: The Fragility Fracture Clinic at the University of Michigan provides comprehensive care to promote bone health, accelerate healing, and reduce fracture risk in those with and at-risk for fractures. Participants (N=344) included those who enrolled at the clinic between 2013 and 2020 and received an abdomen and/or pelvis computed tomography (CT) scan up to 120 days prior to initial enrollment date. Fracture categorizations included acute vs. non-acute, intensity (high vs. low energy), and location (thoracic vs. lumbar vertebral). Retrospective CT-scans were obtained from the University of Michigan Picture Archive and Communication System. Analytic Morphomics was used to obtain granular vertebral-indexed measurements of vertebral bone density, fascia, adipose tissue, muscle, vasculature, and interior body dimensions. Relevant measures include bone mineral density (BMD) [vertebral body trabecular bone density in Hounsfield Units (HU)], lower muscle group density in HU (DMG) (cross sectional area of DMG in HU range of 31-100), cortical bone density [anterior cortical half-maximum (in HU)], and fascial width (in mm). Measurements were divided by their standard deviation to ease interpretation of odds ratios. Multivariable logistic regression was used to evaluate the relationship between body measures and fracture type. Coefficients are reported as odds ratio (OR) and 95% confidence interval (CI). An alpha level of 0.05 determine statistical significance. Results: Associations were observed between acute fracture and BMD at L3 [OR 0.58, 95% CI 0.36-0.85]; high energy fracture and DMG at L3 [OR 2.08, 1.05-4.64]; low energy fracture and BMD at T8 [OR 0.39, 0.17-0.81]; thoracic vertebral fractures and BMD at T11 [OR 0.39, 0.17-0.81], cortical bone density at T11 [OR 0.64, 0.40-0.95], and fascial width at L4 [OR 0.67, 0.43-0.98]; lumbar vertebral fracture and BMD at L3 [OR 0.44, 95% CI 0.20-0.88]. Conclusion: Body composition measures uniquely associated with fracture outcomes. Lower vertebral trabecular bone density was associated with acute, high energy, thoracic vertebral, and lumbar vertebral fractures; lower lean muscle with high energy fractures; cortical bone density and facial (i.e. visceral cavity) width with thoracic vertebral fractures.

Introduction: Aortic calcification can be utilized to assess cardiovascular risk. While contrast is useful for vascular enhancement in diagnostic imaging, enhancement creates heterogeneity between post and non-contrast scans and limits their direct comparability. Hypothesis: We hypothesized that post and non-contrast aortic calcification measures will correlate, and a correction score can be developed for statistical comparability. Methods: Retrospective CT-scans were obtained from the University of Michigan. Participants (N=330) received abdominal scans with and without contrast enhancement within 120 calendar days. Analytic Morphomics was used to obtain vertebral-indexed measurements of aortic calcium area, and aortic wall obfuscation percentage. Calcification was specifically identified as regions with a given morphology and pixel value five standard deviations above the defined central lumen zone. Pearson correlation and multiple linear regression were used to explain the relationship between aortic measurements with and without contrast. Regressions include calcification percent (Model 1), and area (Model 2). Independent variables were non-contrast measurements and dependent variables were contrast measurements, age, and sex. Results: Correlations of calcification percent ranged from 0.86 at T11 and 0.94 and L2. Correlations of calcification area ranged from 0.66 at T12 to 0.84 at L3. In Model 1, for every percent increase in post-contrast calcification, non-contrast calcification percent increased by 11% (β=1.11, p Conclusion: In conclusion, this research proposes a correction score for comparisons of abdominal aortic calcification measurements in post-contrast and non-contrast scans.

Background: Frailty has been shown to be an independent negative predictor of surgical outcomes in geriatric patients. Traditional measurements of frailty are impractical in emergency settings, and computed tomography (CT)-measured skeletal muscle mass has been proposed as an alternative. However, the cutoff values of these CT metrics for frailty are still unknown, and their impact on abdominal emergencies in the elderly population is unclear.Study Design: A total of 462 young trauma patients aged 18-40 years were analyzed to establish sex-specific reference cutoff values for the CT-measured muscle index (MI) and muscle gauge (MG) values. The impacts of low MI and MG values were investigated in 1192 elderly patients (aged ≥ 65 years) undergoing abdominal surgery.Results: The sex-specific cutoff values for MI and MG were determined by adopting European Working Group on Sarcopenia in Older People (EWGSOP) guidelines. The correlation between MG and ageing was significantly stronger than that between MI and ageing. With regard to the MG, the L4 psoas muscle gauge (L4 PMG) was further investigated in an elderly cohort owing to its high predictive value and ease of use in the clinical setting. A low L4 PMG value was an independent risk factor for overall complications and mortality in elderly patients with abdominal emergencies.Conclusion: The current study was the largest study investigating the correlations between MG values and ageing in the Asian population. Frailty, as indicated by a low L4 PMG value, may help surgeons during preoperative decision making regarding geriatric patients with abdominal emergencies.

Measurements of skeletal muscle cross-sectional area, index, and radiation attenuation utilizing clinical computed tomography (CT) scans are used in assessments of sarcopenia, the loss of skeletal muscle mass and function associated with aging. To classify individuals as sarcopenic, sex-specific cutoffs for ‘low’ values are used. Conventionally, cutoffs for skeletal muscle measurements at the level of the third lumbar (L3) vertebra are used, however L3 is not included in several clinical CT protocols. Non-contrast-enhanced CT scans from healthy kidney donor candidates (age 18–40) at Michigan Medicine were utilized. Skeletal muscle area (SMA), index (SMI), and mean attenuation (SMRA) were measured at each vertebral level between the tenth thoracic (T10) and the fifth lumbar (L5) vertebra. Sex-specific means, standard deviations (s.d.), and sarcopenia cutoffs (mean-2 s.d.) at each vertebral level were computed. Associations between vertebral levels were assessed using Pearson correlations and Tukey’s difference test. Classification agreement between different vertebral level cutoffs was assessed using overall accuracy, specificity, and sensitivity. SMA, SMI, and SMRA L3 cutoffs for sarcopenia were 92.2 cm2, 34.4 cm2/m2, and 34.3 HU in females, and 144.3 cm2, 45.4 cm2/m2, and 38.5 HU in males, consistent with previously reported cutoffs. Correlations between all level pairs were statistically significant and high, ranging from 0.65 to 0.95 (SMA), 0.64 to 0.95 (SMI), and 0.63 to 0.95 (SMRA). SMA peaks at L3, supporting its use as the primary site for CT sarcopenia measurements. However, when L3 is not available alternative levels (in order of preference) are L2, L4, L5, L1, T12, T11, and T10. Healthy reference values reported here enable sarcopenia assessment and sex-specific standardization of SMA, SMI, and SMRA in clinical populations, including those whose CT protocols do not include L3.

The purpose of the study is to determine whether a novel semi-automated DIXON-based fat quantification algorithm can reliably quantify visceral fat using a CT-based reference standard. This was an IRB-approved retrospective cohort study of 27 subjects who underwent abdominopelvic CT within 7 days of proton density fat fraction (PDFF) mapping on a 1.5T MRI. Cross-sectional visceral fat area per slice (cm2) was measured in blinded fashion in each modality at intervertebral disc levels from T12 to L4. CT estimates were obtained using a previously published semi-automated computational image processing system that sums pixels with attenuation − 205 to − 51 HU. MR estimates were obtained using two novel semi-automated DIXON-based fat quantification algorithms that measure visceral fat area by spatially regularizing non-uniform fat-only signal intensity or de-speckling PDFF 2D images and summing pixels with PDFF ≥ 50%. Pearson’s correlations and Bland–Altman analyses were performed. Visceral fat area per slice ranged from 9.2 to 429.8 cm2 for MR and from 1.6 to 405.5 cm2 for CT. There was a strong correlation between CT and MR methods in measured visceral fat area across all studied vertebral body levels (r = 0.97; n = 101 observations); the least (r = 0.93) correlation was at T12. Bland–Altman analysis revealed a bias of 31.7 cm2 (95% CI [− 27.1]–90.4 cm2), indicating modestly higher visceral fat assessed by MR. MR- and CT-based visceral fat quantification are highly correlated and have good cross-modality reliability, indicating that visceral fat quantification by either method can yield a stable and reliable biomarker.

Background The "Cushion Effect," the phenomenon in which obesity protects against abdominal injury in adults in motor vehicle accidents, has not been evaluated among pediatric patients. This work evaluates the association between subcutaneous fat cross-sectional area, quantified using analytic morphomic techniques and abdominal injury. Methods This retrospective study includes 119 patients aged 1 to 18years involved in frontal impact motor vehicle accidents (2003–2015) with computed tomography scans. Subcutaneous fat cross-sectional area was measured and converted to age- and gender-adjusted percentiles from population-based normative data. Multivariable analysis determined the risk of the primary outcome, Maximum Abbreviated Injury Scale (MAIS) 2+ abdominal injury, after adjusting for age, weight, seatbelt status, and impact rating. Results MAIS 2+ abdominal injuries occurred in 20 (16.8%) of the patients. Subcutaneous fat area percentile was not significantly associated with MAIS 2+ abdominal injury on multivariable logistic regression (adjusted Odds Ratio, 0.86; 95% CI, 0.72–1.03; p=0.10). Discussion The "cushion effect" was not apparent among pediatric frontal motor vehicle crash victims in this study. Future work is needed to investigate other analytic morphomic measures. By understanding how body composition relates to injury patterns, there is a unique opportunity to improve vehicle safety design. Level of Evidence Prognosis Study, Level III.

Purpose The prognosis of patients with hepatocellular carcinoma (HCC) undergoing transarterial chemoembolization (TACE) is often uncertain. We aimed to utilize analytic morphomics, a high-throughput imaging analysis, to assess if body composition is predictive of post-TACE survival. Materials and Methods We included patients from a single center (Ann Arbor VA)who had TACE as the primary treatment forHCC and had a pre-treatment computed tomography scans. Univariate analysis and multivariate conditional inference tree analysis were utilized to identify the morphomic characteristics predictive of 1-year survival. Results were validated in an external cohort(University of MichiganHealth System) ofHCC patientswho underwent TACE as their primary treatment. Results In the 75 patients in the derivation cohort, median survival was 439 (interquartile range, 377 to 685) days from receipt of TACE, with 1-year survival of 61%. Visceral fat density (VFD) was the only morphomic factor predictive of overall and 1-year survival (p < 0.001). Patients with VFD above the 56th percentile had a 1-year survival of 39% versus 78% for those below the 56th percentile. VFD also correlated with 1-year survival in the external validation cohort (44% vs. 72%, p < 0.001). In a secondary analysis, patients with higher VFD were significantly more likely to experience hepatic decompensation after TACE (p < 0.001). Conclusion VFD served as an objective predictor of mortality in patients undergoing TACE, possibly through its ability to predict hepatic decompensation. VFD may serve as a radiographic biomarker in predicting TACE outcomes.

The purpose of this study was to identify morphomic factors on standard, pretransplantation computed tomography (CT) scans associated with outcomes after lung transplantation.A retrospective review of 200 patients undergoing lung transplantation at a single institution from 2003 to 2014 was performed. CT scans obtained within 1 year before transplantation underwent morphomic analysis. Morphomic characteristics included lung, dorsal muscle group, bone, and subcutaneous and visceral fat area and density. Patient data were gathered from institutional and United Network for Organ Sharing databases. Outcomes, including initial ventilator support greater than 48 hours, length of stay, and survival, were evaluated using univariate and multivariable analyses.On multivariable Cox regression, subcutaneous fat/total body area (hazard ratio [HR] 0.60, p = 0.001), lung density 3 volume (HR 0.67, p = 0.013), and creatinine (HR 4.37, p = 0.010) were independent predictors of survival. Initial ventilator support more than 48 hours was associated with decreased vertebral body to linea alba distance (odds ratio [OR] 0.49, p = 0.002) and Zubrod score 4 (OR 14.0, p0.001). Increased bone mineral density (p0.001) and increased cross-sectional body area (p0.001) were associated with decreased length of stay, whereas supplemental oxygen (p0.001), bilateral transplantation (p = 0.002), cardiopulmonary bypass (p0.001), and Zubrod score 3 (p0.001) or 4 (p = 0.040) were associated with increased length of stay.Morphomic factors associated with lower metabolic reserve and frailty, including decreased subcutaneous fat, bone density, and body dimensions were independent predictors of survival, prolonged ventilation, and increased length of stay. Analytic morphomics using pretransplantation CT scans may improve recipient selection and risk stratification.

Background/purpose Analytic morphomics is being used to identify 3-D biologic measures with superior clinical utility and risk stratification over traditional factors such as age, height, and weight. The purpose of this study is to define age and gender specific Pediatric Reference Analytic Morphomics Population (PRAMP™) growth charts. Methods This retrospective study population contains 2591 individual CT scans of a normative reference population of males and females (1–20years old). Growth curves were constructed at the 5th, 25th, 50th, 75th, and 95th quantiles for morphomic variables, including psoas muscle area, trabecular bone density, and visceral fat area by age and gender. Results Total psoas muscle area increases over time until late adolescence. Trabecular bone density remains stable until adolescence, decreases during adolescence, and increases in young adulthood. Visceral fat area increases over time with greater variation between the 5th and 95th percentile with increasing age. Conclusions The PRAMP™ data have been used to construct age- and sex-specific reference growth curves. This may be used to better define "abnormal" in efforts to create unique risk-categorization algorithms specific to particular clinical and global health investigations. Level of evidence Level II.

Purpose Malnutrition in children is defined by international guidelines as the age-adjusted Z-score for weight or BMI. However, weights can be misleading in children with HF because of fluid retention leading to misclassification of malnutrition level. We sought to estimate the prevalence of sarcopenic malnutrition in pediatric HF patients by quantifying objectively muscle wasting (sarcopenia) relative to age-adjusted normative data for children. Methods All children listed for HT between 2012 and 2017 who underwent thoracic CT as part of transplant surgical planning were identified using a hospital database. The skeletal muscle index (SMI) was defined as the cross-sectional area of skeletal muscle at L3 index to patient, a known predictor of total muscle mass. Age adjusted Z-scores were calculated using normative data from the University of Michigan. Mild, moderate and severe were defined by cut-off Z-scores of -2 and -3, respectively. Results Among 28 children listed for HT, the median age was 10 (IQR 6, 13) years, the median weight was 26 (18, 40) kg, 39% were female, 82% had congenital heart disease. By ASPEN guidelines, the prevalence of mild, moderate and severe malnutrition was 14%, 29% and 25%. The median SMI was 39 cm2/m2 (Z-score, -1.7); the prevalence of sarcopenia by Z-score was 36%, 25% and 10% (figure) (P Conclusion Muscle wasting is common in children with advanced heart failure and can be profound. Conventional definitions for malnutrition in children may misclassify malnutrition severity in children with HF. Normative curves may be helpful for understanding the severity of muscle wasting in children with HF, and may help to guide nutritional replacement.

Background High-dose methotrexate (HD-MTX) is used to treat primary central nervous system lymphoma (PCNSL), but potential differences in MTX clearance (CL) due to obesity have not been studied. We characterized the relationship between HD-MTX CL and computed tomography (CT)-generated body composition (morphomic), body size descriptors, and laboratory measurements in a cohort of obese and non-obese patients with PCNSL. Methods Medical records from adult patients with PCNSL treated with HD-MTX over a 10-year period were queried. Individuals with CT data within 30 days of the first cycle of treatment were included. Population pharmacokinetic analysis was performed using a 2-compartment base structural model. We specifically compared body surface area (BSA) to standard body size, morphomic, and renal function estimation methods as covariates of HD-MTX CL. Results The final data set consisted of non-obese (n=45) and obese (n=28) patients with 291 observations (3-7 samples per patient) with a mean (standard deviation) weight of 69.8 (11.6) kg and 104 (14.9) kg, respectively (p=0.0001). Vertebral body height was more informative than BSA of MTX CL. Similarly, a CL model incorporating age, albumin, and serum creatinine was more informative than kidney function equations and body size. The final model of MTX CL was based on age, albumin, serum creatinine, and vertebral body height. Conclusions Common clinical variables coupled with vertebral body height are more predictive of first cycle MTX CL than BSA, alternate body size descriptors, and commonly used kidney function equations.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a valuable resuscitative adjunct in a variety of clinical settings. In resource-limited or emergency environments, REBOA may be required with delayed or absent image-guidance or verification. Catheter insertion lengths may be informed by making computed tomography (CT) correlations of skeletal landmarks with vascular lengths.Between 2000 and 2015 at a single civilian tertiary care center, 2,247 trauma patients with CT imaging were identified, yielding 1,789 patients with adequate contrast opacification of the arterial system in the chest, abdomen, and pelvis. Individual scans were analyzed using MATLAB software, with custom high-throughput image processing algorithms applied to correlate centerline vascular anatomy with musculoskeletal landmarks. Data were analyzed using R version 3.3.The median centerline distance from the skin access to the aortic bifurcation was longer by 0.3 cm on the right than on the left side. Median aortic zone I length was 21.6 (interquartile range, 20.3-22.9) cm, while zone III was 8.7 (7.8-9.5) cm. Torso extent (TE) correlation to zone I was much higher than that for zone III (R2, 0.58 vs. 0.26 (right) and 0.58 vs. 0.27 (left); p0.001). Assuming a 4-cm balloon length, optimal fixed insertion length would be 48 cm and 28 cm for zones I and III (error, 0.4% vs. 33.3%), respectively, although out of zone placements can be reduced if adjusted for TE (error, 0% vs. 26.4%).Computed tomography morphometry suggests that a fixed REBOA catheter insertion length of 48 cm for zone I and 28 cm for zone III is optimal (on average, for average-height individuals), with improved accuracy by formulaic adjustments for TE. High residual error for zone III placement may require redesign of existing catheter balloon lengths or consideration of the relative risk associated with placing the balloon catheter too low or too high.Prognostic/epidemiological, level III.

Here we present detailed regional bone thickness and cross‐sectional measurements from full adult ribs using high resolution CT scans processed with a cortical bone mapping technique. Sixth ribs from 33 subjects ranging from 24 to 99 years of age were used to produce average cortical bone thickness maps and to provide average ± 1SD corridors for expected cross‐section properties (cross‐sectional areas and inertial moments) as a function of rib length. Results obtained from CT data were validated at specific rib locations using direct measurements from cut sections. Individual thickness measurements from CT had an accuracy (mean error) and precision (SD error) of −0.013 ± 0.167 mm (R (2) coefficient of determination of 0.84). CT‐based measurement errors for rib cross‐sectional geometry were −0.1 ± 13.1% (cortical bone cross‐sectional area) and 4.7 ± 1.8% (total cross‐sectional area). Rib cortical bone thickness maps show the expected regional variation across a typical rib's surface. The local mid‐rib maxima in cortical thickness along the pleural rib aspect ranged from range 0.9 to 2.6 mm across the study population with an average map maximum of 1.4 mm. Along the cutaneous aspect, rib cortical bone thickness ranged from 0.7 to 1.9 mm with an average map thickness of 0.9 mm. Average cross‐sectional properties show a steady reduction in total cortical bone area from 10% along the rib's length through to the sternal end, whereas overall cross‐sectional area remains relatively constant along the majority of the rib's length before rising steeply towards the sternal end. On average, male ribs contained more cortical bone within a given cross‐section than was seen for female ribs. Importantly, however, this difference was driven by male ribs having larger overall cross‐sectional areas, rather than by sex differences in the bone thickness observed at specific local cortex sites. The cortical bone thickness results here can be used directly to improve the accuracy of current human body and rib models. Furthermore, the measurement corridors obtained from adult subjects across a wide age range can be used to validate future measurements from more widely available image sources such as clinical CT where gold standard reference measures (e.g. such as direct measurements obtained from cut sections) are otherwise unobtainable.

Introduction: The severity of injury from motor vehicle crashes (MVCs) depends on complex biomechanical factors, and the bodily features of the injured person account for some of these factors. By assuming that vulnerable road users (VRUs) have limited protection resulting from vehicles and safety equipment, the current study analyzed the characteristics of fat distribution measured by computed tomography (CT) imaging and investigated the existence of a “cushion effect” in VRUs. Materials and Methods: This retrospective study enrolled 592 VRUs involved in MVCs who underwent CT scans. Visceral fat area and subcutaneous fat cross-sectional area were measured and adjusted according to total body area (TBA) and are presented as the visceral fat ratio and the subQ fat ratio (subcutaneous fat ratio). Risk factors for serious abdominal injury (maximum abbreviated injury scale (MAISabd ≥ 3)) resulting from MVCs were determined by univariate and multivariate analysis. Results: MAISabd ≥ 3 was observed in 104 (17.6%) of the patients. The subQ fat ratio at the L4 vertebral level was significantly lower in the MAISabd ≥ 3 group than in the MAISabd &lt, 3 group (24.9 ± 12.0 vs. 28.1 ± 11.9%, p = 0.015). A decreased L4 subQ fat ratio was associated with a higher risk for MAISabd ≥ 3 in multivariate analysis (odds ratio 0.063, 95% CI 0.008–0.509, p = 0.009). Conclusion: The current study supported the “cushion effect” theory, and protection was apparently provided by subcutaneous fat tissue. This concept may further improve vehicle and safety designation in the future.

We aimed to determine whether comprehensive imaging analysis with analytic morphomics (AM) enhances or replaces geriatric assessment (GA) in risk-stratifying pancreatic surgery patients. One hundred thirty-four pancreatic surgery patients were identified from a prospective cohort. Sixty-three patients in the cohort had preoperative CT scans in addition to comprehensive geriatric assessments. CT scans were processed using AM. Associations with National Surgical Quality Improvement Program (NSQIP) serious complications were evaluated using univariate analysis and robust elastic net modeling to obtain AUROC curves by adding AM and GA measures to our previously defined clinical base risk model (age, body mass index, American Society of Anesthesiologists classification, and Charlson comorbidity index). NSQIP serious complications were associated with low psoas Hounsfield units (HUs) (p = 0.002), low-density (0 to 30 HU) psoas area (p = 0.01), visceral fat HU (p ≤ 0.001), visceral fat area (p = 0.009), subcutaneous fat HU (p = 0.023), and total body area (p = 0.012) on univariate analysis. Elastic net models incorporating the base model with geriatric assessment and psoas HU (AUC = 0.751), and AM alone (AUC = 0.739) have greater predictive value than the base model alone (AUC = 0.601). The model utilizing AM and GA in combination had the highest predictive value (AUC = 0.841). When combined, AM and GA improve prediction of NSQIP serious complications compared to either technique alone. The additive nature of these two modalities suggests they likely capture unique aspects of a patient's fitness for surgery.

In patients undergoing neoadjuvant chemoradiotherapy (nCRT) followed by surgery for locally advanced esophageal squamous cell carcinoma (ESCC), patients with a pathologic complete response (pCR) have the greatest benefit. The purpose of this study was to identify morphomic factors obtained from pretreatment computed tomography scans associated with a pCR in ESCC.We retrospectively analyzed patients with ESCC treated with nCRT who underwent esophagectomy between 2006 and 2016. Clinical and morphomic characteristics pre-nCRT were analyzed to identify factors associated with pCR using univariate and multivariable analyses.There were 183 patients with ESCC included in this study, and 45 (24.6%) patients achieved pCR. The overall survival in patients with pCR was better than that in patients without pCR (5.8 years vs 1.2 years; P.001). On univariate analysis, increased age, radiation dose greater than or equal to 4000 cGy, and larger subcutaneous adipose tissue area were correlated with pCR. On multivariable logistic regression, increased age (odds ratio, 1.53; P = .03), radiation dose greater than or equal to 4000 cGy (odds ratio, 2.19; P = .04), and larger dorsal muscle group normal-density area (odds ratio, 1.59; P = .03) were independently associated with pCR.Increased age, radiation dose greater than or equal to 4000 cGy, and larger dorsal muscle group normal-density area were significantly associated with pCR. These factors may be useful in determining which patients are most likely to benefit from nCRT followed by esophagectomy.

e18071 Background: Neuropathy is a common adverse event requiring dose reduction or regimen change in patients receiving platinum-taxane chemotherapy for ovarian cancer. Our aim was to determine whether specific biomarkers, such as skeletal muscle, visceral and subcutaneous fat cross-sectional areas, measured using computerized tomography (CT), were associated with the development of neuropathy. Analytic Morphomics, a semi-automated image analysis method, has been used to predict oncologic outcomes with immunotherapy and to identify patients at higher risk for postoperative complications from major cancer surgeries. We hypothesized that patients who required dose reductions or regimen changes would have CT imaging findings that distinguished them from their counterparts who did not require dose reduction or regimen change. Methods: All patients at our institution diagnosed with high-grade ovarian carcinoma between January 1, 2014 and December 31, 2018 were identified retrospectively. Analytic Morphomics was used to extract measures of body composition from CT images at the level of the third lumbar vertebra. Demographic and clinical characteristics were abstracted from the electronic medical record. We analyzed several binary outcomes (neuropathy, delay in chemotherapy, or dose reduction by cycle 1, 3 or 6) and used unpaired, two-tailed t-tests to compare means between each outcome group at each timepoint. Results: Of 156 patients screened for the study, 138 patients were included and had pre-treatment CT scans available and completed six cycles of platinum-taxane chemotherapy. Patients who developed neuropathy in any of the six cycles, or had a change in their chemotherapy regimen by cycle six, had higher mean visceral fat area than those who did not develop neuropathy. This finding was statistically significant throughout three cycles (p = 0.023) and six cycles (p = 0.030). Conclusions: Increased visceral fat on CT imaging was significantly associated with a higher incidence of neuropathy and change in chemotherapy regimen in patients undergoing primary platinum-taxane chemotherapy for ovarian carcinoma. Weight and BMI did not have a significant association with development of neuropathy, dose reduction, or treatment delay. Further study is needed to determine if dose reductions or regimen changes due to neuropathy can be better predicted using morphomics.

This study assesses the ability to measure local cortical bone thickness, and to obtain mechanically relevant properties of rib cross-sections from clinical-resolution computed tomography (CT) scans of human ribs. The study utilized thirty-four sections of ribs published by Perz et al. (2015) in three modalities: standard clinical CT (clinCT), high-resolution clinical CT (HRclinCT), and microCT (µCT). Clinical-resolution images were processed using a Cortical Bone Mapping (CBM) algorithm applied to cross-cortex signals resampled perpendicularly to an initial smooth periosteal border. Geometric constraints were applied to remove outlier signals from consideration, and final predicted periosteal and endosteal borders from HRclinCT and clinCT were developed. Target values for local cortical thickness and for overall cross-sectional area and inertial properties were obtained from segmentation of the periosteal and endosteal borders on each corresponding µCT image. Errors in prediction (mean ± SD) of local cortical bone thickness for HRclinCT and clinCT resolutions were − 0.03 ± 0.17 mm and − 0.05 ± 0.22 mm, respectively, with R2 coefficients of determination from linear regression of 0.82 and 0.71 (p Predicted cortical shell measures derived from the periosteal and endosteal borders included total cross-sectional area (prediction errors of 6 ± 3% and − 1 ± 5 % respectively for HRclinCT and clinCT with R2 correlations of 0.99 and 0.96), cortical shell area (errors of − 3 ± 8 % and − 8 ± 11 % with R2 correlations of 0.91 and 0.87), and principal area moment of inertia (errors of 2 ± 8% and − 3 ± 11 % with R2 correlations of 0.98 and 0.95). Results here show substantial reductions in rib cross-sectional measurement error compared to past histogram-based thresholding methods and provide first validation of the CBM method when applied to rib bones. With the ubiquity of clinical CT scans covering the thorax and ribs, this study opens the door for individualized and population-wide quantification of rib structural properties and their corresponding effects on rib injury.

Sarcopenia is defined as the loss of skeletal muscle mass and function associated with aging. Muscle mass can be reliably and accurately quantified using clinical CT scans but reference measurements are lacking, particularly in healthy US populations. Two-phase CT scans from healthy kidney donors (age 18-40) at the University of Michigan between 1999-2010 were utilized. Muscle mass was quantified using two thoracic and two lumbar muscle cross-sectional area (CSA) measures. Indexed measurements were computed as area divided by height-squared. Paired analyses of non-contrast and contrast phases and different Hounsfield Unit (HU) ranges for muscle were conducted to determine their effect on CSA muscle measures. We report the means, standard deviations, and 2SD sarcopenia cutoffs from this population. Healthy population CSA (cm2) cutoffs for N=604 males/females respectively were: 34.7/20.9 (T12 Dorsal Muscle), 91.5/55.9 (T12 Skeletal Muscle), 141.7/91.2 (L3 Skeletal Muscle), 23.5/14.3 (L4 Total Psoas Area), and 23.4/14.3 (L4 Psoas Muscle Area). Height-indexed CSA (cm2/m2) cutoffs for males/females respectively were: 10.9/7.8 (T12 Dorsal Muscle), 28.7/20.6 (T12 Skeletal Muscle), 44.6/34.0 (L3 Skeletal Muscle), 7.5/5.2 (L4 Total Psoas Area), and 7.4/5.2 (L4 Psoas Muscle Area). We confirmed that a mask of -29 to 150 HU is optimal and shows no significant difference between contrast-enhanced and non-contrast CT scan CSA measurements. We quantified reference values for lumbar and thoracic muscle CSA measures in a healthy US population. We defined the effect of IV contrast and different HU ranges for muscle. Combined, these results facilitate the extraction of clinically valuable data from the large numbers of existing scans performed for medical indications.

Granular diagnostic criteria for adult malnutrition are lacking.This study uses analytic morphomics to define the Morphomic Malnutrition Score (MMS), a robust screening tool for severe malnutrition.The study population (n = 643) consisted of 2 cohorts: 1) 124 emergency department patients diagnosed with severe malnutrition by a registered dietitian (RD) and an available computed tomography (CT) scan within 2 days of RD evaluation, and 2) 519 adult kidney donor candidates to represent a healthy cohort. Body composition markers of muscle area and abdominal adiposity were measured from patient CT scans using analytic morphomic assessment, and then converted to sex- and age-adjusted percentiles using the Reference Analytic Morphomics Population (RAMP). RAMP consists of 6000 patients chosen to be representative of the general population. The combined cohort was then randomly divided into training (n = 453) and validation (n = 190) sets. MMS was derived using logistic regression. The model coefficients were transformed into a score, normalized from 0 to 10 (10 = most severe).Severely malnourished patients had lower amounts of muscle and fat than kidney donors, specifically for dorsal muscle group area at the twelfth thoracic vertebral level (P 0.001), psoas muscle area at the fourth lumbar vertebral level (P 0.001), and subcutaneous fat area at the third lumbar vertebral level (P 0.001)-all parameters in MMS. MMS for severely malnourished patients was higher than kidney donors (7.7 ± 2.2 vs 3.8 ± 2.0, respectively; P-value 0.001). An MMS 6.1 was accurate in determining nutrition diagnosis (82.1% sensitivity; 88.3% specificity; 85.2% balanced accuracy).MMS provides an evidence-based, granular assessment to distinguish severely malnourished adults from a healthy population.

Antibiotics such as vancomycin are empirically dosed on the basis of body weight, which may not be optimal across the expanding adult body size distribution. Our aim was to compare the relationships between morphomic parameters generated from computed tomography images to conventional body size metrics as predictors of vancomycin pharmacokinetics (PK). This single-center retrospective study included 300 patients with 1,622 vancomycin concentration (52% trough) measurements. Bayesian estimation was used to compute individual vancomycin volume of distribution of the central compartment (Vc) and clearance (CL). Approximately 45% of patients were obese with an overall median (5th, 95th percentile) weight and body mass index of 87.2 (54.7, 123) kg and 28.8 (18.9, 43.7) kg/m 2 , respectively. Morphomic parameters of body size such as body depth, total body area, and torso volume of the twelfth thoracic through fourth lumbar vertebrae (T12 to L4) correlated with Vc. The relationship of vancomycin Vc was poorly predicted by body size but was stronger with T12-to-L4 torso volume (coefficient of determination [ R 2 ] = 0.11) than weight ( R 2 = 0.04). No relationships between vancomycin CL and traditional body size metrics could be discerned; however, relationships with skeletal muscle volume and total psoas area were found. Vancomycin CL independently correlated with total psoas area and inversely correlated with age. Thus, vancomycin CL was significantly related to total psoas area over age ( R 2 = 0.23, P < 0.0001). This proof-of-concept study suggests a potential role for translation of radiographic information into parameters predictive of drug pharmacokinetics. Prediction of individual antimicrobial pharmacokinetic parameters using analytic morphomics has the potential to improve antimicrobial dose selection and outcomes of obese patients.

OBJECTIVES/SPECIFIC AIMS: Patient factors such as body mass index and functional status are commonly used in surgical decision-making and prediction of outcomes. Morphomic analysis uses semi-automated 3D cross-sectional imaging analysis to quantify tissue, organ, and bone geometry and density. These data can be used to assess patient health status. There is an emerging trend of using morphomic variables such as muscle mass and bone mineral density to predict surgical and medical outcomes. In certain cases, it has been shown to predict cancer survival more accurately than conventional staging methods. With the growing popularity of morphomic analysis, it is vital to establish baseline variability against which patient populations can be validated. Of populations receiving radiographic imaging, trauma patients are approximately representative of the general population. We created a reference population of morphomic variables from over 6000 University of Michigan patients presenting with trauma. METHODS/STUDY POPULATION: Computed tomography (CT) scans were obtained for all patients who underwent scans for trauma indications at the University of Michigan starting from April 1998. High throughput image processing algorithms written in MATLAB 2015a were used to semi-automatically process chest, abdomen, and pelvis CT scans. Scans were referenced to a common coordinate system based on vertebral levels and body anatomy. Measurements of adiposity, muscle group, and bone density measurements were performed at each level. Percentile curves of morphomic measures of body composition by age and sex were created. The reference population dataset is periodically updated and is publicly accessible. RESULTS/ANTICIPATED RESULTS: As of July 2017, over 6000 patients aged 1–81 years have been included in the Reference Analytics Morphomics Population. Patient CT scans were analyzed at the T10, T11, T12, L1, L2, L3, and L4 vertebral levels. Morphomic measures analyzed include body depth, body cross-sectional area, vertebral trabecular bone density, visceral fat area, fascia area, subcutaneous fat area, central back fat, and psoas muscle area. DISCUSSION/SIGNIFICANCE OF IMPACT: We created reference curves for several morphomic variables from a Reference Analytic Morphomics Population of over 6000 University of Michigan patients presenting with trauma.

Rationale and Objectives To explore whether the sarcopenia body type can help predict response to interleukin-2 (IL-2) therapy in metastatic renal cell carcinoma (RCC). Materials and Methods Institutional review board approval was obtained for this Health Insurance Portability and Accountability Act-compliant retrospective cohort study of 75 subjects with metastatic RCC who underwent pretreatment contrast-enhanced computed tomography within 1 year of initiating IL-2 therapy. Cross-sectional area and attenuation of normal-density (31–100 Hounsfield units [HU]) and low-density (0–30 HU) dorsal muscles were obtained at the T11 vertebral level. The primary outcome was partial or complete response to IL-2 using RECIST 1.1 criteria at 6 weeks. A conditional inference tree was used to determine an optimal HU cutoff for predicting outcome. Bonferroni-adjusted multivariate logistic regression was conducted to investigate the independent associations between imaging features and response after controlling for demographics, doses of IL-2, and RCC prognostic scales (eg, Heng and the Memorial Sloan Kettering Cancer Center [MSKCC]). Results Most subjects had intermediate prognosis by Heng (65% [49 of 75]) and the MSKCC (63% [47 of 75]) criteria; 7% had complete response and 12% had partial response. Mean attenuation of low-density dorsal muscles was a significant univariate predictor of IL-2 response after Bonferroni correction (P = 0.03). The odds of responding to treatment were 5.8 times higher for subjects with higher-attenuation low-density dorsal muscles (optimal cutoff: 18.1 HU). This persisted in multivariate analysis (P = 0.02). Body mass index (P = 0.67) and the Heng (P = 0.22) and MSKCC (P = 0.08) clinical prognostic scales were not significant predictors of response. Conclusions Mean cross-sectional attenuation of low-density dorsal muscles (ie, sarcopenia) may predict IL-2 response in metastatic RCC. Clinical variables are poor predictors of response.

The Michigan Surgical Home and Optimization Program is a structured, home-based, preoperative training program targeting physical, nutritional, and psychological guidance. The purpose of this study was to determine if participation in this program was associated with reduced hospital duration of stay and health care costs.We conducted a retrospective, single center, cohort study evaluating patients who participated in the Michigan Surgical Home and Optimization Program and subsequently underwent major elective general and thoracic operative care between June 2014 and December 2015. Propensity score matching was used to match program participants to a control group who underwent operative care prior to program implementation. Primary outcome measures were hospital duration of stay and payer costs. Multivariate regression was used to determine the covariate-adjusted effect of program participation.A total of 641 patients participated in the program; 82% were actively engaged in the program, recording physical activity at least 3 times per week for the majority of the program; 182 patients were propensity matched to patients who underwent operative care prior to program implementation. Multivariate analysis demonstrated that participation in the Michigan Surgical Home and Optimization Program was associated with a 31% reduction in hospital duration of stay (P .001) and 28% lower total costs (P .001) after adjusting for covariates.A home-based, preoperative training program decreased hospital duration of stay, lowered costs of care, and was well accepted by patients. Further efforts will focus on broader implementation and linking participation to postoperative complications and rigorous patient-reported outcomes.

Analytic morphomics is a novel methodology that uses high-throughput computed tomography (CT) processing techniques to generate reproducible body measurements (Supplementary Table).1, 2, 3, 4 Body mass index is widely used in clinical and public health studies to predict mortality risk.5 Indeed, we recently examined its impact in allogeneic hematopoietic cell transplantation (HCT) and found that obese patients were at significantly greater risk of mortality compared with normal weight individuals.6 Unfortunately, body mass index does not reliably distinguish adipose tissue mass from muscle mass.7 Therefore, we sought to index patient size using CT measurements.2 The aim of the current study was to apply analytic morphomics in a cohort of allogeneic HCT patients and correlate with clinical outcomes.