Comparison between CT volumetry, technetium99m galactosyl-serum-albumin scintigraphy, and gadoxetic-acid-enhanced MRI to estimate the liver fibrosis stage in preoperative patients

OBJECTIVES

To compare the efficacy of computed tomography volumetry (CTV), technetium99m galactosyl-serum-albumin (99mTc-GSA) scintigraphy, and gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid-enhanced MRI (EOB-MRI) in estimating the liver fibrosis (LF) stage in patients undergoing liver resection.

METHODS

This retrospective study included 91 consecutive patients who had undergone preoperative dynamic CT and 99mTc-GSA scintigraphy. EOB-MRI was performed in 76 patients. CTV was used to measure the total liver volume (TLV), spleen volume (SV), normalised to the body surface area (BSA), and liver-to-spleen volume ratio (TLV/SV). 99mTc-GSA scintigraphy provided LHL15, HH15, and GSA indices. The liver-to-spleen ratio (LSR) was calculated in the hepatobiliary phase of EOB-MRI. Hyaluronic acid and type 4 collagen levels were measured in 65 patients. Logistic regression and receiver operating characteristic (ROC) analyses were performed to identify useful parameters for estimating the LF stage and laboratory data.

RESULTS

According to the multivariable logistic regression analysis, SV/BSA (odds ratio [OR], 1.01; 95% confidence interval [CI], 1.003-1.02; p = 0.011), LSR (OR, 0.06; 95%CI, 0.004-0.70; p = 0.026), and hyaluronic acid (OR, 1.01; 95%CI, 1.001-1.02; p = 0.024) were independent variables for severe LF (F3-4). Combined SV/BSA, LSR, and hyaluronic acid correctly estimated severe LF, with an AUC of 0.91, which was significantly larger than the AUCs of the GSA index (AUC = 0.84), SV/BSA (AUC = 0.83), or LSR (AUC = 0.75) alone.

CONCLUSIONS

Combined CTV, EOB-MRI, and hyaluronic acid analyses improved the estimation accuracy of severe LF compared to CTV, EOB-MRI, or 99mTc-GSA scintigraphy individually.

CLINICAL RELEVANCE STATEMENT

The combined analysis of spleen volume on CT volumetry, liver-to-spleen ratio on gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid-enhanced MRI, and hyaluronic acid can identify severe liver fibrosis associated with a high risk of liver failure after hepatectomy and recurrence in patients with hepatocellular carcinoma.

KEY POINTS

• Spleen volume of CT volumetry normalised to the body surface area, liver-to-spleen ratio of EOB-MRI, and hyaluronic acid were independent variables for liver fibrosis. • CT volumetry and EOB-MRI enable the detection of severe liver fibrosis, which may correlate with post-hepatectomy liver failure and complications. • Combined CT volumetry, gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic-acid-enhanced MRI (EOB-MRI), and hyaluronic acid analyses improved the estimation of severe liver fibrosis compared to technetium99m galactosyl-serum-albumin scintigraphy.

CT volumetry study of microfat graft survival from different donor sites in augmenting the enophthalmic socket

PURPOSE

To evaluate autologous fat grafts harvested from the abdomen versus the thigh for treating the enophthalmic socket using CT volumetry.

METHODS

A randomized prospective interventional study including 20 patients suffering from unilateral enophthalmic socket. Pre-operative clinical assessment included photographs, exophthalmometry reading as well as CT volumetry for volume deficit calculations and the harvesting site was randomly allocated (abdomen or thigh). All patients completed 6 months of follow-up. Exophthalmometry change and percentage of retained fat with the globe included and without it at follow-up were measured.

RESULTS

Microfat graft survival showed no statistically significant correlation with sex, age, or donor site. Mean percentage of retained fat with globe and without it were 14.75% and 25.31%, respectively. Difficulty of extraction and degree of volume deficit correlated significantly with percentage of fat retained. Exophthalmometer change correlated significantly with percentage of fat retained.

CONCLUSION

Autologous fat grafting is a safe and effective technique for volume augmentation of enophthalmic sockets regardless of its harvesting site. CT volumetry has an important role in accurately measuring the volume deficit as well as the postoperative results.

Predicting Safe Liver Resection Volume for Major Hepatectomy Using Artificial Intelligence

(1) Background: Advancements in the field of liver surgery have led to a critical need for precise estimations of preoperative liver function to prevent post-hepatectomy liver failure (PHLF), a significant cause of morbidity and mortality. This study introduces a novel application of artificial intelligence (AI) in determining safe resection volumes according to a patient's liver function in major hepatectomies. (2) Methods: We incorporated a deep learning approach, incorporating a unique liver-specific loss function, to analyze patient characteristics, laboratory data, and liver volumetry from computed tomography scans of 52 patients. Our approach was evaluated against existing machine and deep learning techniques. (3) Results: Our approach achieved 68.8% accuracy in predicting safe resection volumes, demonstrating superior performance over traditional models. Furthermore, it significantly reduced the mean absolute error in under-predicted volumes to 23.72, indicating a more precise estimation of safe resection limits. These findings highlight the potential of integrating AI into surgical planning for liver resections. (4) Conclusion: By providing more accurate predictions of safe resection volumes, our method aims to minimize the risk of PHLF, thereby improving clinical outcomes for patients undergoing hepatectomy.

Optimal liver drainage rate for survival in patients with unresectable malignant hilar biliary obstruction using 3D-image volume analyzer

Background

Drainage exceeding 50% of total liver volume is a beneficial prognostic factor in patients with unresectable malignant hilar biliary obstruction (UMHBO). However, it is unclear what threshold percentage of total liver volume drained ('liver drainage rate') significantly improves survival in patients with UMHBO who received systemic chemotherapy.

Objectives

We aimed to assess the optimal liver drainage rate that improves survival in patients with UMHBO receiving chemotherapy using a three-dimensional (3D)-image volume analyzer.

Design

This study was a single-center retrospective cohort study.

Methods

Data from 90 patients with UMHBO who received chemotherapy after endoscopic biliary drainage using metal stents at Okayama University Hospital from January 2003 to December 2020 were reviewed. The liver drainage rate was calculated by dividing the drained liver volume by the total liver volume using a 3D-image volume analyzer. The primary endpoint was overall survival by liver drainage rate. The secondary endpoints were time to recurrent biliary obstruction (TRBO) and prognostic factors.

Results

The median total liver volume was 1172 (range: 673-2032) mL, and the median liver drainage rate was 83% (range: 50-100). Overall survival was 376 (95% CI: 271-450) days, and patients with >80% drainage (n = 67) had significantly longer survival than those with <80% drainage (n = 23) (450 days versus 224 days, p = 0.0033, log-rank test). TRBO was 201 (95% CI: 155-327) days and did not differ significantly by liver drainage rate. Multivariate Cox proportional hazards regression analysis revealed >80% liver drainage [hazard ratio (HR): 0.35, 95% CI: 0.20-0.62, p = 0.0003] and hilar cholangiocarcinoma (HR: 0.30, 95% CI: 0.17-0.50, p < 0.0001) as significant prognostic factors.

Conclusion

In patients with UMHBO scheduled for chemotherapy, >80% drainage is associated with improved survival. Further prospective multicenter studies are needed to verify the results of this study.

Trail registration

Okayama University Hospital, IRB number: 2108-011.

Accelerating voxelwise annotation of cross-sectional imaging through AI collaborative labeling with quality assurance and bias mitigation

Background

precision-medicine quantitative tools for cross-sectional imaging require painstaking labeling of targets that vary considerably in volume, prohibiting scaling of data annotation efforts and supervised training to large datasets for robust and generalizable clinical performance. A straight-forward time-saving strategy involves manual editing of AI-generated labels, which we call AI-collaborative labeling (AICL). Factors affecting the efficacy and utility of such an approach are unknown. Reduction in time effort is not well documented. Further, edited AI labels may be prone to automation bias.

Purpose

In this pilot, using a cohort of CTs with intracavitary hemorrhage, we evaluate both time savings and AICL label quality and propose criteria that must be met for using AICL annotations as a high-throughput, high-quality ground truth.

Methods

57 CT scans of patients with traumatic intracavitary hemorrhage were included. No participant recruited for this study had previously interpreted the scans. nnU-net models trained on small existing datasets for each feature (hemothorax/hemoperitoneum/pelvic hematoma; n = 77-253) were used in inference. Two common scenarios served as baseline comparison- de novo expert manual labeling, and expert edits of trained staff labels. Parameters included time effort and image quality graded by a blinded independent expert using a 9-point scale. The observer also attempted to discriminate AICL and expert labels in a random subset (n = 18). Data were compared with ANOVA and post-hoc paired signed rank tests with Bonferroni correction.

Results

AICL reduced time effort 2.8-fold compared to staff label editing, and 8.7-fold compared to expert labeling (corrected p < 0.0006). Mean Likert grades for AICL (8.4, SD:0.6) were significantly higher than for expert labels (7.8, SD:0.9) and edited staff labels (7.7, SD:0.8) (corrected p < 0.0006). The independent observer failed to correctly discriminate AI and human labels.

Conclusion

For our use case and annotators, AICL facilitates rapid large-scale curation of high-quality ground truth. The proposed quality control regime can be employed by other investigators prior to embarking on AICL for segmentation tasks in large datasets.

CT volume analysis in living donor liver transplantation: accuracy of three different approaches

OBJECTIVES

The aim of this retrospective study is to compare and evaluate accuracy of three different approaches of liver volume quantification in living donor transplantations.

METHODS

This is a single-center, retrospective study of 60 donors. The total and right lobe liver volumes were analyzed in the portal-venous phase by two independent radiologists who estimated the volumes using manual, semi-automated and automated segmentation methods. The measured right lobe liver volume was compared to the real weight of the graft after back-table examinations.

RESULTS

The mean estimated overall liver volume was 1164.4 ± 137.0 mL for manual, 1277.4 ± 190.4 mL for semi-automated and 1240.1 ± 108.5 mL for automated segmentation. The mean estimated right lobe volume was 762.0 ± 122.4 mL for manual, 792.9 ± 139.9 mL for semi-automated and 765.4 ± 132.7 mL for automated segmentation. The mean graft weight was 711.2 ± 142.9 g. The manual method better correlated with the graft weight (r = 0.730) in comparison with the semi-automated (r = 0.685) and the automated (r = 0.699) methods (p < 0.001). The mean error ratio in volume estimation by each application was 12.7 ± 16.6% for manual, 17.1 ± 17.3% for semi-automated, 14.7 ± 16.8% for automated methods. There was a statistically significant difference between the mean error ratio of the manual and the semi-automated segmentations (p = 0.017), and no statistically significant difference between the manual and the automated applications (p = 0.199).

CONCLUSION

Volume analysis application better correlates with graft weight, but there is no obvious difference between correlation coefficients of all three methods. All three modalities had an error ratio, of which the semi-automated method showed the highest value.

CRITICAL RELEVANCE STATEMENT

Volume analysis application was more accurate, but there is no drastic difference between correlation coefficients of all three methods.

Feasibility of a New Lung Ultrasound Protocol to Determine the Extent of Lung Injury in COVID-19 Pneumonia

BACKGROUND

Lung ultrasound (LUS) scanning is useful to diagnose and assess the severity of pulmonary lesions during COVID-19-related ARDS (CoARDS). A conventional LUS score is proposed to measure the loss of aeration during CoARDS. However, this score was validated during the pre-COVID-19 era in patients with ARDS in the ICU and does not consider the differences with CoARDS. An alternative LUS method is based on grading the percentage of extension of the typical signs of COVID-19 pneumonia on the lung surface (LUSext).

RESEARCH QUESTION

Is LUSext feasible in patients with COVID-19 at the onset of disease, and does it correlate with the volumetric measure of severity of COVID-19 pneumonia lesions at CT scan (CTvol)?

STUDY DESIGN AND METHODS

This observational study enrolled a convenience sampling of patients in the ED with confirmed COVID-19 whose condition demonstrated pneumonia at bedside LUS and CT scan. LUSext was visually quantified. All CT scan studies were analyzed retrospectively by a specifically designed software to calculate the CTvol. The correlation between LUSext and CTvol, and the correlations of each score with Pao2/Fio2 ratio were calculated.

RESULTS

We analyzed data from 179 patients. Feasibility of LUSext was 100%. Time to perform LUS scan was 5 ± 1.5 mins. LUSext and CTvol were correlated positively (R = 0.67; P < .0001). Both LUSext and CTvol showed negative correlation with Pao2/Fio2 ratio (R = -0.66 and R = -0.54; P < .0001, respectively).

INTERPRETATION

LUSext is a valid measure of the severity of the lesions when compared with the CT scan. Not only are LUSext and CTvol correlated, but they also have similar inverse correlation with the severity of respiratory failure. LUSext is a practical and simple bedside measure of the severity of pneumonia in CoARDS, whose clinical and prognostic impact need to be investigated further.

Surgical Management Algorithm for Intrathoracic Sleeve Migration: A Retrospective Series and Literature Review

Background: With the increase in utilization of laparoscopic sleeve gastrectomy (LSG), intrathoracic sleeve migration (ITSM) has introduced a novel challenge for bariatric surgeons. Despite being an underreported complication, effective and safe solutions for ITSM are being sought. The aim of this study is to present our center's experience as well as a comprehensive review of the literature on ITSM. Accordingly, we propose an algorithm for the surgical management of ITSM. Methods: We conducted a retrospective chart review of 4000 patients who underwent LSG at our center. ITSM was clinically suspected with gastroesophageal reflux disease (GERD) symptoms and/or epigastric pain resistant to proton pump inhibitors. Diagnosis of ITSM was confirmed in all patients by three-dimensional computed tomography (3D-CT) volumetry. Several corrective procedures were offered based on the findings of the 3D-CT volumetry, esophagogastroduodenoscopy, and the diaphragmatic pillars' condition: cruroplasty with gastropexy, one anastomosis gastric bypass (OAGB), or Roux-en-Y gastric bypass (RYGB) with or without re-sleeve gastrectomy, omentopexy, or ligamentum teres augmentation. We conducted a literature review of ITSM using several databases. Results: Fifteen patients were diagnosed with postoperative ITSM. The most common presenting complaint was severely worsened GERD symptoms not responding to medical treatment. The mean time interval between the primary operation and diagnosis of ITSM was 38.8 ± 29.1 months. Three patients had re-sleeve gastrectomy and gastropexy, 5 patients had OAGB, and 7 patients had RYGB. The mean postoperative body mass index was 31.2 ± 4.9 kg/m². No case of recurrent ITSM was detected during follow-up. Our electronic database search yielded 19 studies to be included in our review, which included 201 patients. Conclusion: A high index of suspicion is required to diagnose ITSM. CT volumetry with 3D reconstruction may be the most sensitive diagnostic modality. ITSM management should depend on the results of the diagnostic workup and the condition of the diaphragmatic pillars during surgery.

Prognostic value of malnutrition evaluated using the Global Leadership Initiative on Malnutrition criteria and its association with psoas muscle volume in non-ischemic dilated cardiomyopathy

Heart failure (HF) is a systemic inflammatory disease that causes hypotrophy and skeletal muscle loss. The Global Leadership Initiative on Malnutrition (GLIM) criteria have been developed as a novel evaluation index for malnutrition, with reported usefulness in HF caused by ischemic heart disease. However, reports on the usefulness of malnutrition evaluated by the GLIM criteria in non-ischemic dilated cardiomyopathy (NIDCM) and its relationship with psoas muscle volume are lacking. We investigated the prognostic value of malnutrition evaluated using the GLIM criteria and its association with psoas muscle volume in patients with NIDCM. We enrolled 139 consecutive patients with NIDCM between December 2000 and June 2020. Malnutrition was evaluated using the GLIM criteria on admission. The median follow-up period was 4.7 years. Cardiac events were defined as a composite of cardiac death, hospitalization for worsening HF, and lethal arrhythmia. Furthermore, we measured the psoas muscle volume using computed tomography volumetry in 48 patients. At baseline, the median age was 50 years, and 132 patients (95.0%) had New York Heart Association functional class I or II HF. The median psoas muscle volume was 460.8 cm³. A total of 26 patients (18.7%) were malnourished according to the GLIM criteria. The Kaplan-Meier survival analysis showed that malnourished patients had more cardiac events than non-malnourished patients (log-rank, P < 0.001). The multivariate Cox proportional hazards regression analysis revealed that GLIM criteria-based malnutrition was an independent determinant of cardiac events (hazard ratio, 2.065; 95% confidence interval, 1.166-3.656; P = 0.014). Psoas muscle volume, which was assessed in a total of 48 patients, was lower in malnourished than in non-malnourished patients (median, 369.0 vs. 502.3 cm³; P = 0.035) and correlated with body mass index (r = 0.441; P = 0.002). Nutritional screening using the GLIM criteria may be useful in predicting future cardiac events in patients with NIDCM, reflecting a potential relationship between malnutrition and a low psoas muscle volume.

Comparison of tomographic kidney volumes measured by semi-automatic segmentation method with scintigraphic split renal function in predicting posttransplant kidney functions

INTRODUCTION

In this study, it was aimed to compare scintigraphic split renal function (SRF) and computed tomographic (CT) kidney volumes by semi-automatic segmentation method in predicting graft functions after kidney transplantation.

METHODS

112 patients (77 males, 35 females) who had a living donor kidney transplant between 2015 and 2017 in our center were included in the study. While SRF was calculated with technetium-99m-diethylenetriaminepentaacetic acid (^99m Tc-DTPA) scintigraphy, CT angiography was used for volumetric calculations.

RESULTS

CT-volumetric measurements, especially renal cortical volume (RCV:103.8 ± 20 mL) and ratio to body mass index (RCV/BMI:4.45±1.3) were found to be more significant than ^99m Tc-DTPA-SRF in predicting graft functions. The correlations between SRF and RCV with 6th month eGFR (rSRF:0.052, rRCV:0.317, p=0.041) and 1st year eGFR (rSRF:0.104, rRCV:0.374, p=0.033) were found to be more significant in favor of RCV. The correlation between SRF/BMI and RCV/BMI with 1st, 6th and 12th month eGFR (respectively, p=0.02/0.048/0.024) were found to be more significant in favor of RCV/BMI. Although univariate analysis showed a significant relationship between most volumetric measurements and 1st year graft functions, in multivariate analysis only RCV (OR: 1.04(1.01-1.07), p=0.023) and RCV/BMI (OR: 2.5(1.27-5.39), p=0.013) showed a significant relationship between graft functions.

CONCLUSION

In our study, it was shown that CT-based renal volumetric measurements, especially RCV and RCV/BMI, predicted graft functions more strongly than scintigraphic ^99m Tc-DTPA-SRF. This article is protected by copyright. All rights reserved.

Nintedanib in idiopathic and secondary pleuroparenchymal fibroelastosis

Background

Pleuroparenchymal fibroelastosis (PPFE) has a variable disease course with dismal prognosis in the majority of patients with no validated drug therapy. This study is to evaluate the effect of nintedanib in patients with idiopathic and secondary PPFE. Patients admitted to a tertiary care center (2010–2019) were included into this retrospective analysis if they had a multidisciplinary diagnosis of PPFE, had been followed-up for 3 months or more, and had lung function tests and chest CTs available for review. Changes in pulmonary function tests were assessed using non-parametric tests and linear mixed effect model. Lung volumes were measured with lobar segmentation using chest CT.

Results

Out of 21 patients with PPFE, nine had received nintedanib, six had received another treatment and another six patients were monitored without drug therapy. Annual FVC (% of predicted) relative decline was − 13.6 ± 13.4%/year before nintedanib and − 1.6 ± 6.02%/year during nintedanib treatment (p = 0.014), whereas no significant change in FVC% relative decline was found in patients receiving another treatment (− 13.25 ± 34 before vs − 16.61 ± 36.2%/year during treatment; p = 0.343). Using linear mixed effect model, the slope in FVC was − 0.97%/month (95% CI: − 1.42; − 0.52) before treatment and − 0.50%/month (95% CI: − 0.88; 0.13) on nintedanib, with a difference between groups of + 0.47%/month (95% CI: 0.16; 0.78), p = 0.004. The decline in the upper lung volumes measured by CT was − 233 mL/year ± 387 mL/year before nintedanib and − 149 mL/year ± 173 mL/year on nintedanib (p = 0.327). Nintedanib tolerability was unremarkable.

Conclusion

In patients with PPFE, nintedanib treatment might be associated with slower decline in lung function, paving the way for prospective, controlled studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-02043-5.

Correlation of gastrointestinal perforation location and amount of free air and ascites on CT imaging

PURPOSE

To analyze the amount of free abdominal gas and ascites on computed tomography (CT) images relative to the location of a perforation.

METHODS

We retrospectively included 172 consecutive patients (93:79 = m:f) with GIT perforation, who underwent abdominal surgery (ground truth for perforation location). The volume of free air and ascites were quantified on CT images by 4 radiologists and a semiautomated software. The relation of the perforation location (upper/lower GIT) and amount of free air and ascites was analyzed by the Mann-Whitney test. Furthermore, best volume cutoff for upper and lower GIT perforation, areas under the curve (AUC), and interreader volume agreement were assessed.

RESULTS

There was significantly more abdominal ascites with upper GIT perforation (333 ml, range 5 to 2000 ml) than with lower GIT perforation (100 ml, range 5 to 2000 ml, p = 0.022). The highest volume of free air was found with perforations of the stomach, descending colon and sigmoid colon. Significantly less free air was found with perforations of the small bowel and ascending colon compared to the aforementioned. An ascites volume > 333 ml was associated with an upper GIT perforation demonstrating an AUC of 0.63 ± 0.04.

CONCLUSION

Using a two-step process based on the volumes of free air and free fluid can help localizing the site of perforation to the upper, middle or lower GI tract.

Hepatic volume profiles in potential living liver donors with anomalous right-sided ligamentum teres

PURPOSE

In living liver donors with rare anatomical anomaly of right-sided ligamentum teres (RSLT), right or left hemiliver procurement is commonly contraindicated. The purpose of this study was to evaluate the hepatic volume profiles in potential donors with RSLT using semi-automated CT volumetry (CTV).

METHODS

Among 5535 potential donor candidates in our institution between April 2003 and May 2019, 23 cases of RSLT (0.4%) were included. Proportional liver volumes were measured using semi-automated CTV and compared with those of manual volumetry and intraoperative graft weights (seven surgical cases).

RESULTS

The mean percentage volume of the right posterior section was significantly larger than that of the left hemiliver (38.5 ± 8.4% vs. 23.3 ± 5.7%, P < 0.001). Particularly in independent right lateral type, the mean percentage volume of the right posterior section was about two times larger to that of the left hemiliver (41.5% ± 6.5% vs. 21.9% ± 4.4%, P < 0.001), whereas the volume proportions of these two parts were similar between the two parts in bifurcation and trifurcation types (P = 0.810 and 0.979, respectively). Semi-automated CTV of corresponding whole liver, right posterior section, right anterior section, and left hemiliver showed strong correlations with manual CTV (r = 0.989-0.998; P < 0.001). For the seven surgical cases, the graft weights estimated by semi-automated CTV showed a significant correlation with intraoperative graft weights (r = 0.972; P < 0.001).

CONCLUSION

In independent right lateral type of RSLT, the right posterior section tends to be significantly larger than left hemiliver, and may be an alternative option for graft in potential living liver donors with this rare anatomical anomaly.

Use of volumetric CT scanning to predict tumor staging and survival in pancreatic cancer patients that are to be administered curative resection

BACKGROUND

This study evaluates the achievability of CT volumetry of pancreatic cancer and its correlation with pTNM stage and survival.

METHODS

Tumor volume was measured from contrast enhanced CT images of 58 patients who undergo curative resection for pancreatic cancer using the Segment Editor module implemented in 3D-Slicer-a free open source software platform. Receiver operating characteristic (ROC) analysis was used to evaluate correlation between Tvol and pTNM staging.

RESULTS

The preoperative images of 58 pancreatic adenocarcinoma patients were included. The mean Tvol of pancreatic cancer is an increasing trend with T stage (The mean T1vol = 1.75 cm³ , the mean T2vol = 11.43 cm³ , the mean T3vol = 14.98 cm³ , the mean T4vol = 19.6 cm³ ). There were statistical differences between volumes (p = .000). On ROC analysis, the area under the ROC curve (Az) of Tvol to differentiate T1 stage from ≥T2 stage was 0.966 (p = .000). At a cut-off value of 3.050 cm³ , sensitivity of 92.3%, and specificity of 83.3% were achieved. Az value of Tvol to differentiate ≤T2 from ≥T3 stage was 0.750 (p = .010). At a cut-off value of 10.250 cm³ , sensitivity of 72.7% and specificity of 66% were achieved. In addition Az value of Tvol to differentiate ≤T3 from ≥T4 stage was 0.652 and was not significant (p = .380). At a cut-off value of 11.2 cm³ , sensitivity of 66.7% and specificity of 63.6% were achieved.

CONCLUSION

CT volumetry in pancreatic cancer is feasible with excellent reproducibility. It is one of the prognostic factors affecting survival in operated patients with pancreatic cancer.

Morphologic Study of Gastric Sleeves by CT Volumetry at One Year after Laparoscopic Sleeve Gastrectomy

PURPOSE

Laparoscopic sleeve gastrectomy (SG) is now frequently performed as a definitive bariatric procedure. The aim of the study was to evaluate the detailed morphology of remnant stomachs after SG with respect to volume and sleeve migration.

MATERIALS AND METHODS

We performed a retrospective review of prospectively collected data on patients that completed a 12-month postop examination, which included CT volumetry of sleeve, and a questionnaire that addressed postop food tolerance. CT volumetry study included total sleeve volume (TSV), tube volume (TV), antral volume (AV), tube/antral volume ratio (TAVR), and the presence of intrathoracic sleeve migration (ITSM).

RESULTS

Fifty-five patients were included in this retrospective study. Mean %TWL (% total weight loss) at 12 months postop was 32.8% (14.3-55.5), and mean TSV, TV, AV, and TAVR were 166.6±63.3 ml, 68.9±35.4 ml, 97.7±42.9 ml, and 0.8±0.6 respectively. TSV was not correlated significantly with %TWL at 12 months postop (r=-0.069, P=0.619). Fourteen patients (14/55, 25.5%) showed ITSM by CT. Patients with ITSM had a significantly lower mean GER score (5.1±2.0 vs. 7.3±2.0, P=0.001), a lower total food tolerance score (21.6±3.8 vs. 24.4±4.6, P=0.048), and a higher proportion showed suboptimal weight loss (35.7% vs. 9.8%, P=0.023).

CONCLUSION

Mean TSV was not found to be significantly correlated with %TWL at 12 months postop. Patients with suboptimal weight loss had higher mean TAVR, and the presence of ITSM indicated more frequent GER symptoms, lower food tolerance, and a higher probability of suboptimal weight loss.

Correlation of weight loss with residual gastric volume on computerized tomography in patients undergoing sleeve gastrectomy: A systematic review

Laparoscopic Sleeve gastrectomy (LSG) is the most commonly performed bariatric surgical procedure worldwide. There is wide variation however in post-operative weight loss on long term follow-up, and residual gastric volume (RGV) is believed to be an important variable. Multiple studies have correlated RGV as assessed by Computerized Tomography volumetry with excess weight loss (EWL%) following LSG, but definite consensus is lacking. This article systematically reviews the published studies in English literature to ascertain whether any correlation exists between the RGV and EWL% following LSG. Ten studies were included in this review, and significant differences were noted in the technique of RGV assessment, and timing of RGV and EWL% assessment. Five studies found a statistically significant correlation between the RGV and EWL%. One study found a correlation which did not reach statistical significance. Two additional studies reported that the resected volume rather than RGV correlated with the EWL%. Meta-analysis of studies reporting correlation between RGV and EWL% showed that up to 26.3% (95% CI: 5.1%-56.1%) of variability in EWL% can be explained by variations in RGV. A lower RGV is likely to result in a better post-operative weight loss following LSG. There is need for standardization of technique and timing of RGV assessment.

Correlation between arterial blood gas and CT volumetry in patients with SARS-CoV-2 in the emergency department

•

The severity of SARS-CoV-2 patients is difficult to quickly assess in the ED.

•

The ABG test is a quick and easy tool that can help identify more severe patients.

•

CT cannot be used on all suspected SARS-CoV-2 infected patients admitted in ED.

•

The CT volumetry correlates well with the values of severity reported by the ABG test.

Analysis of Medium-Term Weight Regain 5 Years After Laparoscopic Sleeve Gastrectomy

OBJECTIVE

Some patients fail to maintain weight loss after bariatric surgery. Weight regain (WR) disturbs the patients due to possible reappearance of obesity-related comorbidities. This study aimed to assess WR 5 years after laparoscopic sleeve gastrectomy (LSG).

PATIENTS AND METHODS

This retrospective study included 100 adults who underwent LGS. The percentage of excess weight loss (%EWL) was recorded. WR was defined as an increase of at least 10% of the lowest postoperative weight. Patients with WR were subjected to CT gastric volumety. Eating behavior was assessed by the Three-Factor Eating Questionnaire-Revised 18-Items (TFEQ-R18).

RESULTS

Preoperative comorbidities improved in 89.5% of the patients. Twenty-five females (32.5%) got pregnant within 3 years after surgery. Age, maximum weight loss, and uncontrolled and emotional eating scales of the TFEQ-R18 were independently affecting %EWL. Also, pregnancy negatively affected %EWL. Fourteen patients regain weight: 11 females and three males. CT volumetry of the 14 patients showed a median stomach volume of 515 mL (range 172-1066 mL). CT estimated gastric volume was negatively correlated with % EWL (r = - 0.674, p = 0.008). Patients who developed WR were significantly older (p = 0.006), with lower maximum weight loss, and having higher scores of uncontrolled and emotional eating scales of TFEQ-R18.

CONCLUSION

Medium-term postsurgical weight regain and unsuccessful weight loss in patients who had undergone LSG is associated with older age, maladaptive eating behavior, larger residual stomach, and pregnancy.

Optimal Attenuation Threshold for Quantifying CT Pulmonary Vascular Volume Ratio

Objective

To evaluate the effects of attenuation threshold on CT pulmonary vascular volume ratios in children and young adults with congenital heart disease, and to suggest an optimal attenuation threshold.

Materials and Methods

CT percentages of right pulmonary vascular volume were compared and correlated with percentages calculated from nuclear medicine right lung perfusion in 52 patients with congenital heart disease. The selected patients had undergone electrocardiography-synchronized cardiothoracic CT and lung perfusion scintigraphy within a 1-year interval, but not interim surgical or transcatheter intervention. The percentages of CT right pulmonary vascular volumes were calculated with fixed (80–600 Hounsfield units [HU]) and adaptive thresholds (average pulmonary artery enhancement [PA_avg] divided by 2.50, 2.00, 1.75, 1.63, 1.50, and 1.25). The optimal threshold exhibited the smallest mean difference, the lowest p-value in statistically significant paired comparisons, and the highest Pearson correlation coefficient.

Results

The PA_avg value was 529.5 ± 164.8 HU (range, 250.1–956.6 HU). Results showed that fixed thresholds in the range of 320–400 HU, and adaptive thresholds of PA_avg/1.75–1.50 were optimal for quantifying CT pulmonary vascular volume ratios. The optimal thresholds demonstrated a small mean difference of ≤ 5%, no significant difference (> 0.2 for fixed thresholds, and > 0.5 for adaptive thresholds), and a high correlation coefficient (0.93 for fixed thresholds, and 0.91 for adaptive thresholds).

Conclusion

The optimal fixed and adaptive thresholds for quantifying CT pulmonary vascular volume ratios appeared equally useful. However, when considering a wide range of PA_avg, application of optimal adaptive thresholds may be more suitable than fixed thresholds in actual clinical practice.

Spleen size improvement in advanced heart failure patients using a left ventricular assist device

The spleen has been recognized as an important organ that holds a reserve of 20% to 30% of the total blood volume. Spleen contraction and splenic volume reduction occur in patients with hypovolemic shock. However, the change in the spleen volume and the association between spleen size and hemodynamic parameters remain unclear in patients with advanced heart failure (HF) who need left ventricular assist device (LVAD) support. This study was performed to investigate the change in spleen size and the relationship between spleen size and hemodynamic parameters before and after LVAD implantation in patients with advanced HF. We enrolled 20 patients with advanced HF on LVAD support. All patients underwent right heart catheterization and computed tomography before and after LVAD implantation. The spleen size was measured by computed tomography volumetry. We excluded patients with a mean right atrial pressure (RAP) of <5 mm Hg because of the possibility of hypovolemia and those with a cardiac index of >2.2 L/min/m² before LVAD implantation. The splenic volume significantly increased from 160.6 ± 46.9 mL before LVAD implantation to 224.6 ± 73.5 mL after LVAD implantation (P < .001). Before LVAD implantation, there was a significant negative correlation between spleen volume and systemic vascular resistance (SVR). After LVAD implantation, however, there were significant correlations between spleen volume and the cardiac index, RAP, and pulmonary capillary wedge pressure despite the absence of a significant correlation between spleen volume and SVR. Furthermore, one patient developed reworsening HF because of LVAD failure due to pump thrombosis. In this case, the splenic volume was 212 mL before LVAD implantation and increased to 418 mL after LVAD implantation, although it decreased to 227 mL after LVAD failure. The spleen size may change depending on hemodynamics in patients with advanced HF with LVAD support, reflecting sympathetic nerve activity and the systemic volume status.

Estimation of the Right Posterior Section Volume in Live Liver Donors: Semiautomated CT Volumetry Using Portal Vein Segmentation

RATIONALE AND OBJECTIVES

To determine the accuracy of semiautomated CT volumetry using portal vein (PV) segmentation to estimate volume of the right posterior section (RPS) graft compared to intraoperative measured weight (W) in live liver donors.

MATERIALS AND METHODS

Among 23 donors who donated RPS grafts for liver transplantation in our institution from April 2003 to August 2016, 17 donors with CT scans within 3 months of liver procurement and PV anatomy of type I-III were included. RPS volumes were retrospectively evaluated by semiautomated CT volumetry (RPSV_CTV) and by measurement of standard liver volume (SLV) and PV area ratio (RPSV_SLV). RPS volumes were compared to W for correlation coefficients, (absolute) difference, and (absolute) percentage deviation. Linear fitting was performed to identify the method that yielded the greatest correlation with W.

RESULTS

Mean values of RPSV_CTV, RPSV_SLV, and W were 503.4 ± 97.8 mL (346.6-686.0), 516.54 ± 146.20 (274.06-776.32), and 518.8 ± 122.4 (370.0-789.0), respectively. RPSV_CTV was strongly correlated with W (r = 0.9414; p < 0.0001), whereas RPSV_SLV was only moderately did (r = 0.5899; p = 0.0127). RPSV_CTV showed a significantly smaller absolute difference (35.20 ± 30.82 vs. 104.79 ± 60.27, p = 0.004) and absolute percentage deviation (6.61 ± 4.90 vs. 19.92 ± 10.37, p < 0.0001) from W. Equation correlating RPSV_CTV and W was W = -74.7191 + 1.1791 RPSV_CTV (R² = 0.8862; p < 0.001).

CONCLUSION

RPSV_CTV yields smaller absolute difference than RPSV_SLV for estimating intraoperative measured weight of RPS in live liver donors. Semiautomated CT volumetry using PV segmentation is feasible for the estimation of the volume of the RPS of the liver, and RPSV_CTV was strongly correlated with W (r = 0.9414; p < 0.0001).

Incidence of and risk factors for lymphocele formation after lateral pelvic lymph node dissection for rectal cancer: a retrospective study

AIM

Pelvic lymphocele is a common complication that develops after pelvic lymph node dissection. The incidence of pelvic lymphocele formation has been reported to be 10.5-51% after gynaecological or urological procedures. However, no evidence has been reported thus far with regard to the development of pelvic lymphocele following lateral pelvic lymph node dissection (LPND) for low rectal cancer. The aim of this study was to investigate the incidence of and risk factors for lymphocele formation after LPND for low rectal cancer and to examine its clinical management.

METHOD

We retrospectively analysed the incidence of and risk factors for pelvic lymphocele formation after LPND for rectal cancer in our hospital between January 2012 and December 2017. We also compared the size of the lymphocele between asymptomatic and symptomatic patients by using CT volumetry and examined its clinical management.

RESULTS

A total of 30 out of 98 patients (30.8%) developed pelvic lymphocele after rectal LPND. The number of resected nodes was significantly higher in patients with a pelvic lymphocele (P < 0.01). The median volume was significantly higher in patients with symptomatic pelvic lymphocele (P = 0.011). Among the nine symptomatic patients, two underwent CT-guided drainage, one underwent transurethral ureteral stent placement and one underwent laparoscopic marsupialization.

CONCLUSION

It is essential to keep in mind the possibility of pelvic lymphocele formation during follow-up of patients who undergo LPND, and to consider an appropriate treatment when these patients are symptomatic.

Chitinase-3-Like Protein 1, Serum Amyloid A1, C-Reactive Protein, and Procalcitonin Are Promising Biomarkers for Intracranial Severity Assessment of Traumatic Brain Injury: Relationship with Glasgow Coma Scale and Computed Tomography Volumetry

OBJECTIVE

The volume and location of intracranial hematomas are well-known prognostic factors for traumatic brain injury. The aim of this study was to determine the relationship of serum biomarkers S100β, glial fibrillary acidic protein, neuron-specific enolase, total tau, phosphorylated neurofilament heavy chain, serum amyloid A1 (SAA1), C-reactive protein, procalcitonin (PCT), and chitinase-3-like protein 1 (YKL-40) with traumatic brain injury severity and the amount and location of hemorrhagic traumatic lesions.

METHODS

A prospective observational cohort of 115 patients with a Glasgow Coma Scale (GCS) score of 3-15 were evaluated. Intracranial lesion volume was measured from the semiautomatic segmentation of hematoma on computed tomography using Analyze software. The establishment of possible biomarker cutoff points for intracranial lesion detection was estimated using the Youden Index (J) obtained from the area under the receiver operating characteristic curve.

RESULTS

SAA1, YKL-40, PCT, and S100β showed the most robust association with level of consciousness, both with total GCS and motor score. Biomarkers significantly correlated with volumetric measurements of subdural hematoma, traumatic subarachnoid hemorrhage, intraparenchymal hemorrhage, intraventricular hemorrhage, and total amount of bleeding. The type of intracranial hemorrhage was associated with various release patterns of neurobiochemical markers.

CONCLUSIONS

YKL-40, SAA1, C-reactive protein, and PCT combined with S100β were the most promising biomarkers to determine the presence, location, and extent of traumatic intracranial lesions. Combination of biomarkers further increased the discriminatory capacity for the detection of intracranial bleeding.

Prediction model of compensation for contralateral kidney after living-donor donation

Background

Compensation of contralateral kidney function after living-donor kidney donation is well known, and many predictive factors have been proposed. However, no prediction model has been proposed. This study was performed to establish a tool with which to estimate the degree of compensation of the contralateral kidney after living-donor kidney donation.

Methods

We retrospectively analyzed 133 living donors for renal transplantation in our institution. We defined a favorable compensation as a post-donation estimated glomerular filtration rate (eGFR) at 1 year (calculated by the Chronic Kidney Disease Epidemiology Collaboration equation) of > 60% of the pre-donation eGFR. We analyzed the living donors’ clinical characteristics and outcomes.

Results

The median (range) donor age was 59 (24–79) years, median (range) body mass index was 22.9 (16.8–32.7) kg/m², and median (range) body surface area was 1.6 (1.3–2.0) m². All donors were Japanese, and 73% of the donors were biologically related. The median (range) donor pre-donation eGFR was 108.7 (82–144) ml/min/1.73 m², and the median (range) post-donation eGFR at 1 year was 86.9 (43–143) ml/min/1.73 m². Eighty-six percent of donors had compensatory hypertrophy. In the univariate analysis, age, female sex, history of hypertension, body surface area, and pre-donation eGFR were significantly associated with hypertrophy (p < 0.05). In the multivariate analysis, age, female sex, history of hypertension, and ratio of the remnant kidney volume to body weight were significantly associated with hypertrophy (p < 0.05). Based on these results, we created a compensation prediction score (CPS). The median (range) CPS was 8.7 (1.1–17.4). Receiver operating characteristic analysis showed strong diagnostic accuracy for predicting favorable compensation (area under the curve, 0.958; 95% confidence interval, 0.925–0.991, p < 0.001). The optimal cut-off value of the CPS was 5.0 (sensitivity, 92.0%; specificity, 89.5%). The CPS had a strong positive correlation with the post-donation eGFR (R = 0.797, p < 0.001).

Conclusion

The CPS might be useful tool with which to predict a favorable compensation of the contralateral kidney and remnant kidney function. If the CPS is low, careful management and follow-up might be necessary. Further investigations are needed to validate these findings in larger populations.

[Application of multi-slice spiral CT to assess vascular volume for the diagnosis and treatment of gastric varices]

Objective: To differentiate the inflow and outflow channels of gastric varices in cirrhotic portal hypertension patients using multi-slice spiral CT (MSCT), and to assess the relationship between calculable CT volume of gastric varices and the amount of tissue adhesive. Methods: 97 cases with cirrhotic gastric varices who were admitted from November 2013 to August 2017 were selected. The type and shape of gastric varices were observed before tissue glue injection treatment by MSCT. The correlation between CT volume of gastric varices and the amount of tissue adhesive was evaluated by Spearman rank correlation coefficient and Univariate linear regression analysis. Results: MSCT showed that Le, g type had the highest proportion (54.6%), followed by Le, g, Lg (20.6%). Le, Lg and Lgf type accounted for 17.5%, and 5.2%, respectively, while Lgf+b accounted for 2.1%. On MSCT, varices of the gastric fundus were in the direction from bottom to top, and 75% of the fundus had a large curved side varices combined with gastric and renal shunt. Under the gastroscopy, varices in the small curved side of the gastric fundus from near to far were formless. In addition, varices in the large curved side of the gastric fundus when observed from different angles to the direction of blood flow (reverse gastroscope) were 72.7% (near and far) or 20.5 % (far and near). There was a positive correlation between CT volume (R = 0.97, P < 0.001) and the amount of tissue adhesive (Y(1) = 0.35 + 0.65X1, Univariate linear regression equation; ρ = 0.89, P < 0.001, Spearman correlation analysis). Conclusion: MSCT can recognize the vascular shape and inflow and outflow channels of gastric varices. A positive correlation between CT volume and the amount of tissue adhesive, suggested that the CT volume measurement before treatment could be used as one of the method to predict the amount of tissue adhesive.

Pre-donation BMI and preserved kidney volume can predict the cohort with unfavorable renal functional compensation at 1-year after kidney donation

BACKGROUND

The magnitude of renal function recovery after kidney donation differs in donors with a heterogeneous background. Preoperative assessment of candidates with potentially unfavorable renal functional compensation is critical when baseline kidney function is marginal. We explored the significance of preserved kidney volume (PKV) and known preoperative risk factors for the prediction of unfavorable renal function compensation.

METHODS

We enrolled 101 living donors for whom a 1-mm sliced enhanced computed tomography scan was performed preoperatively and clinical data could be collected up to 1 year after donation. The donors whose estimated glomerular filtration rate (eGFR) at 1 year after donation was 70% or higher of baseline eGFR were assigned to the "favorable renal compensation" group and the others to the "unfavorable renal compensation" group.

RESULTS

Age, sex, and preoperative serum uric acid level were not significant predictors for "unfavorable renal compensation." Multivariable logistic regression analysis revealed that body mass index (BMI) and body surface area (BSA)-adjusted PKV were independent preoperative risk factors for "unfavorable renal compensation" (adjusted odds ratio, 1.342 and 0.929, respectively). Hypertension and preoperative eGFR were not independent predictors when adjusted with BMI and BSA-adjusted PKV. Receiver operative characteristic analysis revealed that the predictive equation with the two independent predictors yielded a good accuracy to detect donor candidates with unfavorable renal functional compensation (area under the curve = 0.803), and the optimal cut-off values were identified as 23.4 kg/m² for BMI and 107.3 cm³/m² for BSA-adjusted PKV.

CONCLUSIONS

BMI and BSA-adjusted PKV may be useful to select candidates with potentially unfavorable renal function compensation before kidney donation.

Accuracy of preoperative CT liver volumetry in living donor hepatectomy and its clinical implications

Background

An accurate preoperative volumetric assessment of donor liver is essential for successful living donor liver transplant by ensuring adequate remnant and graft recipient weight ratio (GRWR).

Methods

The study cohort consisted of 744 right lobe (RL), 65 left lobe (LL) and 33 left lateral sector (LLS) grafts from July 2010 to January 2014. A semi-automated interactive commercial software called AW Volume share 6 was used for volumetry. Bland Altman plot was used for assessing the agreement between estimated graft weight (EGW) and actual graft weight (AGW).

Results

There was no statistically significant difference between EGW and AGW for RL graft weight (722±134 vs. 717±126 gm; P=0.06). Although Bland Altman graph showed that 95% limits of agreement was more in LL (-164 to +110) than RL (-156 to +147) and LLS grafts (-137 to +239), CT scan significantly overestimated LL graft weight (EGW =460±118 gm vs. AGW =433±102 gm; P=0.003) and underestimated LLS graft weight (EGW =203±48 gm vs. AGW =254±49 gm; P<0.001).

Conclusions

CT volumetry overestimate LL graft and underestimate LLS graft weight. This should be factored in when selecting LL graft by taking higher GRWR.

Neither ischemic parenchymal volume nor severe grade complication correlate transient high transaminase elevation after liver resection

To clarify whether high transient elevation of serum transaminase predicts severe complications and is related to the ischemic area on CT. Postoperative laboratory data and ischemia area on CT were analyzed on the basis of the presence of high transaminase elevation (aspartate aminotransferase (AST) > 1,000 IU/L within postoperative day (POD) 2 after liver resection. In the high elevation group, volume of ischemic areas was assessed by CT on POD2. The 538 patients were divided into a high transaminase group (n = 51) and a control group (n = 487). Median operation time (527 min vs. 360 min, p < 0.01) and liver ischemia time (121 min vs. 70 min, p < 0.01) were significantly longer, and intraoperative blood loss (478 mL [85-1572 mL] vs. 269 mL [5-4491 mL], p < 0.01) was significantly greater in the high transaminase group. No significant differences observed in frequency of severe complications (Clavien-Dindo classification Grade III or more) or postoperative hospitalization. Operation time (> 500 min; odds ratio (OR), 4.86; 95% confidence interval (CI), 2.40-9.89; p < 0.01) and liver ischemia time (> 120 min; OR, 3.47; 95%CI, 1.67-7.17; p < 0.01) were independent predictors of high transaminase elevation. No relationship was observed between degree of transaminase elevation and ischemic area (correlation coefficients: AST, R² < 0.001; alanine aminotransferase, R² = 0.005) CT volumetry on POD2. In conclusions, high transaminase elevations do not predict severe complications or reflect remnant ischemic area.

Ursodeoxycholic acid in advanced polycystic liver disease: A phase 2 multicenter randomized controlled trial

BACKGROUND & AIMS

Ursodeoxycholic acid (UDCA) inhibits proliferation of polycystic human cholangiocytes in vitro and hepatic cystogenesis in a rat model of polycystic liver disease (PLD) in vivo. Our aim was to test whether UDCA may beneficially affect liver volume in patients with advanced PLD.

METHODS

We conducted an international, multicenter, randomized controlled trial in symptomatic PLD patients from three tertiary referral centers. Patients with PLD and total liver volume (TLV) ⩾2500ml were randomly assigned to UDCA treatment (15-20mg/kg/day) for 24weeks, or to no treatment. Primary endpoint was proportional change in TLV. Secondary endpoints were change in symptoms and health-related quality of life. We performed a post-hoc analysis of the effect of UDCA on liver cyst volume (LCV).

RESULTS

We included 34 patients and were able to assess primary endpoint in 32 patients, 16 with autosomal dominant polycystic kidney disease (ADPKD) and 16 with autosomal dominant polycystic liver disease (ADPLD). Proportional TLV increased by 4.6±7.7% (mean TLV increased from 6697ml to 6954ml) after 24weeks of UDCA treatment compared to 3.1±3.8% (mean TLV increased from 5512ml to 5724ml) in the control group (p=0.493). LCV was not different after 24weeks between controls and UDCA treated patients (p=0.848). However, UDCA inhibited LCV growth in ADPKD patients compared to ADPKD controls (p=0.049).

CONCLUSIONS

UDCA administration for 24weeks did not reduce TLV in advanced PLD, but UDCA reduced LCV growth in ADPKD patients. Future studies might explore whether ADPKD and ADPLD patients respond differently to UDCA treatment.

LAY SUMMARY

Current therapies for polycystic liver disease are invasive and have high recurrence risks. Our trial showed that the drug, ursodeoxycholic acid, was not able to reduce liver volume in patients with polycystic liver disease. However, a subgroup analysis in patients that have kidney cysts as well showed that liver cyst volume growth was reduced in patients who received ursodeoxycholic acid in comparison to patients who received no treatment. Trial registration number https://www.clinicaltrials.gov/: NCT02021110. EudraCT Number https://www.clinicaltrialsregister.eu/: 2013-003207-19.

Algorithm Variability in the Estimation of Lung Nodule Volume From Phantom CT Scans: Results of the QIBA 3A Public Challenge

RATIONALE AND OBJECTIVES

Quantifying changes in lung tumor volume is important for diagnosis, therapy planning, and evaluation of response to therapy. The aim of this study was to assess the performance of multiple algorithms on a reference data set. The study was organized by the Quantitative Imaging Biomarker Alliance (QIBA).

MATERIALS AND METHODS

The study was organized as a public challenge. Computed tomography scans of synthetic lung tumors in an anthropomorphic phantom were acquired by the Food and Drug Administration. Tumors varied in size, shape, and radiodensity. Participants applied their own semi-automated volume estimation algorithms that either did not allow or allowed post-segmentation correction (type 1 or 2, respectively). Statistical analysis of accuracy (percent bias) and precision (repeatability and reproducibility) was conducted across algorithms, as well as across nodule characteristics, slice thickness, and algorithm type.

RESULTS

Eighty-four percent of volume measurements of QIBA-compliant tumors were within 15% of the true volume, ranging from 66% to 93% across algorithms, compared to 61% of volume measurements for all tumors (ranging from 37% to 84%). Algorithm type did not affect bias substantially; however, it was an important factor in measurement precision. Algorithm precision was notably better as tumor size increased, worse for irregularly shaped tumors, and on the average better for type 1 algorithms. Over all nodules meeting the QIBA Profile, precision, as measured by the repeatability coefficient, was 9.0% compared to 18.4% overall.

CONCLUSION

The results achieved in this study, using a heterogeneous set of measurement algorithms, support QIBA quantitative performance claims in terms of volume measurement repeatability for nodules meeting the QIBA Profile criteria.

Pancreatic volume is one of the independent prognostic factors for resectable pancreatic ductal adenocarcinomas

BACKGROUND

It is well known that pancreatic ductal adenocarcinoma (PDAC) is accompanied with pancreatic atrophy and fibrosis. We previously reported the correlation between pancreatic volume and body surface area (BSA) and significant reduction of BSA-adjusted pancreatic volume in pancreatic cancer patients. We evaluated potential correlation between BSA-adjusted pancreatic volume and PDAC prognosis.

METHODS

The study subjects were 48 pancreatic cancer patients received pancreatectomy at our department from June 2006 to September 2012. Pancreatic volumetry was retrospectively performed using the images obtained from multidetector computed tomography before the surgery. BSA-adjusted pancreatic volumes were calculated and analyzed for potential correlation with the prognosis.

RESULTS

Average BSA-adjusted pancreatic volume among 48 cases was 35.4 ± 11.9 ml/m(2) . Types of surgery included 24 cases with pancreaticoduodenectomy and 24 cases with distal pancreatectomy. The cases with BSA-adjusted pancreatic volume less than 40 ml/m(2) had significantly poorer prognosis compared to the cases of 40 ml/m(2) and greater (3-year survival rate: 32.4% vs. 64.3%). Statistical analysis identified four prognosis factors, i.e. BSA-adjusted pancreatic volume less than 40 ml/m(2) , postoperative adjuvant chemotherapy, lymph node metastasis and lymphatic invasion.

CONCLUSIONS

This study demonstrated BSA-adjusted pancreatic volume as a prognosis factor for PDAC and the volume of 40 ml/m(2) is considered to be the cutoff value.

Comparison of Tc-99m GSA scintigraphy and CT volumetry for evaluation in portal vein embolization

PURPOSE

To determine the correlation of the rate of change of each future remnant liver (FRL) before and after portal vein embolization (PVE), by CT volumetry and Tc-99m galactosyl human serum albumin scintigraphy (GSA scintigraphy).

MATERIAL AND METHODS

From December 2007 to July 2012, ten patients underwent PVE before hepatic resection. CT volumetry and GSA scintigraphy were performed before and after PVE. The FRL was divided at Cantlie's line for CT volumetry, and volume change rates before and after PVE were calculated. The maximum removal rate (Rmax) was calculated using a radiopharmacokinetic model in GSA scintigraphy. The FRL Rmax change rates before and after PVE were calculated. The correlation between the volume change rates and the Rmax change rates was analyzed.

RESULTS

The FRL volume change rate was 1.28 ± 0.26 (mean ± SD); the FRL hypertrophied in all patients significantly (p = 0.005). The FRL Rmax change rate was 1.66 ± 0.75; excluding one patient, there was significant FRL Rmax increase (p = 0.022). Although both increased significantly, no correlation between the volume change rate and the Rmax change rate was observed.

CONCLUSION

No correlation was observed between the FRL volume rate and the Rmax rate.

Correlation of CT perfusion and CT volumetry in patients with Alzheimer's disease

BACKGROUND

Both brain atrophy and decrease of perfusion are observed in dementive diseases. The aim of the study was to correlate the results of brain perfusion CT (pCT) and CT volumetry in patients with Alzheimer's disease (AD).

MATERIAL/METHODS

Forty-eight patients with AD (mean age of 71.3 years) underwent brain pCT and CT volumetry. The pCT was performed at the level of basal ganglia after the injection of contrast medium (50 ml, 4 ml/sec.) with serial scanning (delay 7 sec, 50 scans, 1 scan/sec). Volumetric measurements were carried out on the basis of source images, with the use of a dedicated CT software combined with manual outlining of the regions of interest in extracerebral and intraventricular CSF spaces. Perfusion parameters of the cerebral blood flow (CBF) and cerebral blood volume (CBV) from the grey matter of frontal and temporal as well as basal ganglia were compared statistically with the volumetric measurements of frontal and temporal cortical atrophy as well as subcortical atrophy.

RESULTS

A statistically significant positive correlation was found between the values of CBF and CBV in the basal ganglia and the volumes of the lateral and third ventricles. The comparison of CBF and CBV results with the volumetric measurements in the areas of the frontal and temporal lobes showed mostly negative correlations, but none of them was of statistical significance.

CONCLUSIONS

In patients with AD, the degree of cortical atrophy is not correlated with the decrease of perfusion in the grey matter and subcortical atrophy is not correlated with the decrease of perfusion in the basal ganglia region. It suggests that functional and structural changes in AD are not related to each other.