Measurement of visceral fat on preoperative computed tomography predicts complications after sigmoid colectomy for diverticular disease

Opportunistic CT for Prediction of Adverse Postoperative Events in Patients with Spinal Metastases

The purpose of this study was to assess the value of body composition measures obtained from opportunistic abdominal computed tomography (CT) in order to predict hospital length of stay (LOS), 30-day postoperative complications, and reoperations in patients undergoing surgery for spinal metastases. 196 patients underwent CT of the abdomen within three months of surgery for spinal metastases. Automated body composition segmentation and quantifications of the cross-sectional areas (CSA) of abdominal visceral and subcutaneous adipose tissue and abdominal skeletal muscle was performed. From this, 31% (61) of patients had postoperative complications within 30 days, and 16% (31) of patients underwent reoperation. Lower muscle CSA was associated with increased postoperative complications within 30 days (OR [95% CI] = 0.99 [0.98-0.99], p = 0.03). Through multivariate analysis, it was found that lower muscle CSA was also associated with an increased postoperative complication rate after controlling for the albumin, ASIA score, previous systemic therapy, and thoracic metastases (OR [95% CI] = 0.99 [0.98-0.99], p = 0.047). LOS and reoperations were not associated with any body composition measures. Low muscle mass may serve as a biomarker for the prediction of complications in patients with spinal metastases. The routine assessment of muscle mass on opportunistic CTs may help to predict outcomes in these patients.

Sarcopenia and body fat change as risk factors for radiologic incisional hernia following robotic nephrectomy

OBJECTIVE

To assess the effect of body muscle and fat metrics on the development of radiologic incisional hernia (IH) following robotic nephrectomy.

MATERIALS AND METHODS

We retrospectively reviewed the records of patients who underwent robotic nephrectomy for kidney tumors between 2011 and 2017. All pre- and postoperative CTs were re-reviewed by experienced radiologists for detection of radiologic IH and calculation of the following metrics using Synapse 3D software: cross-sectional psoas muscle mass at the level of L3 and L4 as well as subcutaneous and visceral fat areas. Sarcopenia was defined as psoas muscle index below the lowest quartile. Cox proportional hazard model was constructed to examine the association between muscle and fat metrics and the risk of developing radiologic IH.

RESULTS

A total of 236 patients with a median (IQR) age of 64 (54-70) years were included in this study. In a median (IQR) follow-up of 23 (14-38) months, 62 (26%) patients developed radiologic IH. On Cox proportional hazard model, we were unable to detect an association between sarcopenia and risk of IH development. In terms of subcutaneous fat change from pre-op, both lower and higher values were associated with IH development (HR (95% CI) 2.1 (1.2-3.4), p = 0.01 and 2.4 (1.4-4.1), p < 0.01 for < Q1 and ≥ Q3, respectively). Similar trend was found for visceral fat area changes from pre-op with a HR of 2.8 for < Q1 and 1.8 for ≥ Q3.

CONCLUSION

Both excessive body fat gain and loss are associated with development of radiologic IH in patients undergoing robotic nephrectomy.

Body Composition Predictors of Adverse Postoperative Events in Patients Undergoing Surgery for Long Bone Metastases

Body composition assessed using opportunistic CT has been recently identified as a predictor of outcome in patients with cancer. The purpose of this study was to determine whether the cross-sectional area (CSA) and the attenuation of abdominal subcutaneous adipose tissue, visceral adipose tissue (VAT), and paraspinous and abdominal muscles are the predictors of length of hospital stay, 30-day postoperative complications, and revision surgery in patients treated for long bone metastases.

Excessive Body Weight and Diverticular Disease

BACKGROUND

The worldwide proportion of overweight adults almost doubled from 22% in 1975 to 39% in 2016. Comparably, for the USA and Germany in 2016, the proportion was 68 and 56.8%, respectively. In Olmsted County, Minnesota, the prevalence of diverticulitis also doubled between 1980 and 2007, from 19 to 40%. Obesity substantially increases the risk of multiple gastrointestinal (GI) diseases and non-GI diseases. In a narrative review, we examined the evidence on whether obesity also increases the risk for the development of diverticulosis or diverticular disease and its outcome.

SUMMARY

Evidence suggests that being overweight (body mass index ≥25 kg/m2) or obese (≥30 kg/m2), especially viscerally obese, is a risk factor for diverticulosis, diverticular disease and diverticulitis, diverticular bleeding, more severe or complicated disease, recurrent disease, and for worse outcomes after surgery.

KEY MESSAGES

There is a well-founded association between overweight and diverticular disease as well as diverticulosis. It is not clear whether overweight per se or confounders linked with it are responsible for the association. However, means to fight the overweight and obesity epidemic might also help to reduce the prevalence of morbidity and mortality from diverticular disease.

Impact of the preoperative body composition indexes on intraoperative blood loss in patients undergoing pancreatoduodenectomy

PURPOSES

This study sought to identify any significant predictors of blood loss during pancreatoduodenectomy (PD) among preoperative variables, including the body composition indexes.

METHODS

The preoperative data of patients undergoing PD were retrospectively reviewed. The objective variable was the percentage of blood loss during PD to the estimated circulating blood volume (proportional blood loss: PBL). The circulating blood volume was estimated using Nadler's formula. The total psoas area, average Hounsfield units of psoas area (psoas muscle density: PMD), and visceral to subcutaneous adipose tissue area ratio (VSR) were measured at the third vertebra using preoperative plain computed tomography images. A univariate analysis and multiple linear regression analysis for PBL were conducted using the preoperative variables.

RESULTS

A total of 415 patients were analyzed. The median PBL was 24.5%. The PMD (coefficient - 0.267; 95% CI - 0.518, - 0.015), VSR (coefficient 2.719; 95% CI 0.238, 5.201), serum albumin level (coefficient - 8.458; 95% CI - 13.02, - 3.898), neoadjuvant therapy (coefficient 9.605; 95% CI 1.722, 17.49), and prothrombin time-international normalized ratio (PT-INR, coefficient 38.63; 95% CI 10.94, 66.31) were independently associated with PBL.

CONCLUSIONS

The preoperative PMD, VSR, serum albumin level, neoadjuvant therapy, and PT-INR independently affected PBL. These factors could therefore be potential targets to reduce blood loss during PD.

The role of quantitative radiological measures of visceral adiposity in diverticulitis

BACKGROUND

Diverticular disease has been linked to obesity. Recent studies have assessed the role of visceral adiposity with diverticulitis and its complications. The aim of this study was to evaluate the association of quantitative radiological measures of visceral adiposity in patients with diverticulitis with vital signs, biochemistry results, uncomplicated versus complicated diverticulitis and its interventions.

METHODS

A retrospective analysis of all patients with diverticulitis admitted from November 2015 to April 2018 at a single institution was performed. Data collected included demographics, vital signs, biochemistry results, CT scan findings and management outcomes. The patients were divided into uncomplicated (U) and complicated diverticulitis (C) groups. Visceral fat area (VFA), subcutaneous fat area (SFA) and VFA/SFA ratio (V/S) were measured at L4/L5 level by the radiologist. Statistical analysis was performed to evaluate the association of VFA, SFA, V/S with the parameters in both U and C groups.

RESULTS

352 patients were included in this study (U:C = 265:87). There was no significant difference in vital signs and biochemistry results in both groups. There was no significant difference in VFA, SFA, V/S ratios in both groups. In patients with V/S ratio > 0.4, they were 5.06 times more likely to undergo emergency intervention (95% CI 1.10-23.45) (p = 0.03). On multivariate analysis, a heart rate > 100 (OR 2.9, 95% CI 1.2-6.7), CRP > 50 (OR 3.4, 95% CI 1.9-6.0), WCC < 4 or > 12 (OR 2.1, 95% CI 1.2-3.6) and V/S ratio > 0.4 (OR 2.8, 95% CI 1.5-5.4) were predictive of complicated diverticulitis.

CONCLUSION

The quantitative radiological measurement of visceral adiposity is useful in prognostication in patients presenting with diverticulitis.

Visceral fat area, not body mass index, predicts postoperative 30-day morbidity in patients undergoing colon resection for cancer

PURPOSE

Colectomy for cancer in obese patients is technically challenging and may be associated with worse outcomes. Whether visceral obesity, as measured on computed tomography, is a better predictor of complication than body mass index (BMI) or determines long-term oncologic outcomes has not been well characterized. This study examines the association between derived anthropometrics and postoperative complication and long-term oncologic outcomes.

METHODS

Retrospective review of patients undergoing elective colectomy for cancer at a single tertiary-care center from 2010 to 2016. Adipose tissue distribution measurements, including visceral fat area (VFA), were determined from preoperative imaging. The primary outcome was 30-day postoperative complication; secondary outcomes included overall and disease-free survival. Multivariable logistic regression was performed to determine association between obesity metrics and outcome.

RESULTS

Two hundred and sixty-four patients underwent 266 primary resections of colon cancer. Twenty-eight patients (10.5%) developed major morbidity (Clavien-Dindo grade ≥ III). VFA but not BMI was significantly associated with morbidity in multivariate analysis (p = 0.004, odds ratio 1.99, 95% confidence interval 1.25-3.19). No other imaging-derived anthropometric was associated with increased morbidity. In receiver operating characteristic analysis, VFA was predictive of major morbidity (area under curve 0.660). A cutoff value of VFA ≥ 191 cm² was associated with 50% sensitivity and 76% specificity for predicting major morbidity. Patients with VFA ≥ 191cm² had 19.4% risk of morbidity, whereas those with < 191 cm² had 7.2% risk (relative risk ratio 2.69, unadjusted p = 0.004). Neither VFA nor BMI was associated with overall or disease-free survival.

CONCLUSION

VFA but not BMI predicts morbidity following elective surgery for colon cancer.

Computed Tomography Morphometrics and Pulmonary Intolerance in Endometrial Cancer Robotic Surgery

STUDY OBJECTIVES

To identify morphometric characteristics of obese patients that best predict pulmonary intolerance to robotic pelvic surgery using a novel method for quantifying adipose distribution.

DESIGN

Retrospective study (Canadian Task Force classification II-2).

SETTING

University hospital.

PATIENTS

Fifty-nine patients with endometrial cancer who underwent robotic hysterectomy and lymphadenectomy between April 2008 and May 2014 and also underwent perioperative computed tomography (CT) imaging within 1 year.

INTERVENTION

Visceral fat volume (VFV) and subcutaneous fat volume (SFV) were quantified through waist circumference measurements along with average volume estimation of slices taken at 3 levels: mid-waist, L2-L3, and L4-L5. Mean and maximum values were obtained for intraoperative physiological data.

MEASUREMENTS AND MAIN RESULTS

The patients' mean body mass index (BMI) was 34 (range, 20-59). Along with waist circumference, VFV and SFV quantified by CT at the mid-waist, L2-L3, and L4-L5 levels were all significant independent predictors for peak airway pressure (PAP; average and maximum) and plateau airway pressure (Pplat; average and maximum) on multivariate regression analysis after adjustment for age, ethnicity, diabetes, hypertension, pulmonary disease, smoking, obstructive sleep apnea, American Society of Anesthesiologists classification, and duration of anesthesia. Compared with the other CT parameters, L2-L3 VFV was the best predictor of average PAP (β = 0.398; p = .002), maximum PAP (β = 0.493; p < .001), average Pplat (β = 0.536; p < .001), and maximum Pplat (β = 0.573; p < .001).

CONCLUSION

These novel CT morphometric measurements represent valid predictors of pulmonary intolerance to robotic surgery in obese patients. Of the measures analyzed, VFV at L2-L3 best predicts pulmonary tolerance in obese patients.

A short-duration restrictive diet reduces visceral adiposity in the morbidly obese surgical patient

BACKGROUND

This study aims to determine if visceral obesity can be reduced after a brief preoperative diet in obese patients.

METHODS

Forty morbidly obese patients were placed on a 1,000 kCal per day diet for 14 days before bariatric surgery. Patients had weight measurements and an abdominal ultrasound performed on days 1 and 14. The ultrasound measured visceral obesity using the distance between the abdominal muscle and the aorta, the fat thickness of the perinephric space, and the distance between the abdominal muscle and splenic vein. Mesenteric fat burden was calculated and compared.

RESULTS

Thirty-eight patients (95%) lost weight on the diet, with a mean loss of 5.2 lbs. Twenty-five patients (63%) had a reduction in mesenteric fat. The average visceral obesity lost was 7.76 cm³ or 3% of the visceral adiposity of the average obese patient (250 cm³).

CONCLUSIONS

A short preoperative calorie restricting diet is well tolerated and results in a reduction in visceral obesity.

Prevalence of Sarcopenia and Its Impact on Postoperative Outcome in Patients With Crohn's Disease Undergoing Bowel Resection

BACKGROUND

Sarcopenia has been proposed to be a prognostic factor of outcomes for various diseases but has not been applied to Crohn's disease (CD). We aimed to assess the impact of sarcopenia on postoperative outcomes after bowel resection in patients with CD.

MATERIALS AND METHODS

Abdominal computed tomography images within 30 days before bowel resection in 114 patients with CD between May 2011 and March 2014 were assessed for sarcopenia as well as visceral fat areas and subcutaneous fat areas. The impact of sarcopenia on postoperative outcomes was evaluated using univariate and multivariate analyses.

RESULTS

Of 114 patients, 70 (61.4%) had sarcopenia. Patients with sarcopenia had a lower body mass index, lower preoperative levels of serum albumin, and more major complications (15.7% vs 2.3%, P = .027) compared with patients without sarcopenia. Moreover, predictors of major postoperative complications were sarcopenia (odds ratio [OR], 9.24; P = .04) and a decreased skeletal muscle index (1.11; P = .023). Preoperative enteral nutrition (OR, 0.13; P = .004) and preoperative serum albumin level >35 g/L (0.19; P = .017) were protective factors in multivariate analyses.

CONCLUSION

The prevalence of sarcopenia is high in patients with CD requiring bowel resection. It significantly increases the risk of major postoperative complications and has clinical implications with respect to nutrition management before surgery for CD.