Liver Fibrosis in Asians With Metabolic Dysfunction-Associated Fatty Liver Disease.

BACKGROUND & AIMS: This study aimed to evaluate risk factors associated with liver fibrosis in metabolic dysfunction-associated fatty liver disease (MAFLD). METHODS: A cross-sectional study of 967 Korean patients with MAFLD involved a cohort from a health screening program during the years 2015-2018. The patients were classified into 4 MAFLD subgroups: group 1 (overweight). group 2 (obese), group 3 (lean/normal weight with metabolic abnormalities), and group 4 (diabetes). Liver fibrosis was assessed based on liver stiffness measurement (LSM) value using 2-dimensional real-time magnetic resonance elastography. We investigated differences in liver fibrosis according to MAFLD subgroup classification and determined the risk factors for significant fibrosis. RESULTS: The mean age was 50.8 years, and 869 (90%) patients were male. The mean value of LSM in magnetic resonance elastography was 2.48 ± 0.47 kPa. Significant fibrosis (LSM ≥2.97 kPa) was observed in 66 (6.8%) of 967 patients. The proportion of significant fibrosis in MAFLD group 1, group 2, group 3, and group 4 was 1.3%, 5.5%, 6.4%, and 18.9%, respectively (P < .001). Multivariable analysis indicated that the risk factors for significant fibrosis were serum ferritin ≥300 ng/mL (odds ratio [OR], 1.96; 95% confidence interval [CI], 1.10-3.49; P = .023), Fibrosis-4 ≥1.3 (OR, 2.97; 95% CI, 1.68-5.24; P < .001), homeostatic model assessment of insulin resistance ≥2.0 (OR, 2.60; 95% CI, 1.25-5.43; P = .011), metabolic syndrome (OR, 2.53; 95% CI, 1.31-4.88; P = .006), and MAFLD group 4 (OR, 6.93; 95% CI, 1.96-24.51; P = .003). However, the etiology of liver disease was not statistically associated with liver fibrosis. CONCLUSION: Liver fibrosis in patients with MAFLD varies according to subgroup classification based on diabetes, body mass index, and metabolic risk factors.

Lifestyle Modification Leads to Spatially Variable Reduction in Hepatic Steatosis in Potential Living Liver Donors.

The spatial variability of hepatic fat reduction in potential living liver donors with hepatic steatosis (HS) who undergo lifestyle modification has not been investigated. Here, we aimed to examine the intrasegmental and intersegmental variability of changes in liver attenuation on computed tomography (CT) in potential living liver donors with HS after diet modification and exercise. A total of 87 living liver donor candidates (30.5 ± 7.0 years; 74 males) with biopsy-proven macrovesicular fat (MaF) ≥10% were included. All underwent diet modification and exercise to improve HS, baseline and follow-up unenhanced CT scans, and liver biopsies. Attenuation and its variability (mean and standard deviation, respectively, in Hounsfield units) in segmental, lobar, superficial, deep, and whole areas of the liver were measured across 32 different regions of interest on both baseline and follow-up CT. At baseline, the right lobe and superficial areas of liver showed significantly lower and more variable attenuation than left lobe and deep areas. Greater variability was noted in patients with more severe HS. Mean interval changes in liver attenuation and variability before and after diet modification and exercise were 13.7 (range, -10.6 to 46.2) and 4.7 (1.6-10.6), respectively. The mean interval change in liver attenuation was significantly higher in the right lobe than in the left (14.7 versus 12.7; P < 0.001), and in superficial areas than in deep areas (14.0 versus 13.4; P = 0.02). Greater variability and larger interval changes in liver attenuation were noted in those who responded (≥20% decrease in MaF) to diet modification and exercise than in those who did not. In conclusion, potential living liver donors with HS show significant intrasegmental and intersegmental variability in hepatic fat reduction on CT before and after diet modification and exercise.

Diagnostic Performance for Hepatic Artery Occlusion After Liver Transplantation: Computed Tomography Angiography Versus Contrast-Enhanced Ultrasound.

The purpose of this study was to compare the diagnostic performance of computed tomography angiography (CTA) and contrast-enhanced ultrasound (CEUS) when used to diagnose significant hepatic artery occlusion (HAO) in patients that was suspected on Doppler ultrasound (US). Among 3465 adult liver transplantations (LTs) performed between January 2010 and February 2018, 329 recipients were suspected of having HAO by Doppler US. In these patients, 139 recipients who had undergone both CTA and CEUS as second-line studies were included. CTA and CEUS were retrospectively reviewed using the criteria for HAO used in previous studies (CTA, ≥50% stenosis at the anastomosis; CEUS, no HA enhancement or delayed and discontinuous enhancement). The diagnostic values of CTA and CEUS were compared using the McNemar test. CEUS showed statistically significant better accuracy and specificity than CTA in patients with Doppler US abnormality seen after LT (accuracy, 99.3% versus 89.2%, P < 0.001; specificity, 100% versus 83.1%, P < 0.001). CTA had 15 false-positive diagnoses, and CEUS had 1 false-negative diagnosis. In conclusion, CEUS showed higher specificity and positive predictive value than CTA for the diagnosis of HAO in selected patients with a Doppler US abnormality. However, even if there is no HAO diagnosed on CEUS, continuous monitoring and follow-up imaging are required when HAO is strongly suspected in the clinical setting and on CTA.

Clinical usefulness of gadoxetic acid-enhanced MRI for evaluating biliary anatomy in living donor liver transplantation.

OBJECTIVES: To determine the incremental value of hepatobiliary-phase-MRC (HBP-MRC) added to T2-magnetic resonance cholangiography (T2-MRC) for evaluating biliary anatomy in living donor liver transplantation (LDLT) and to correlate T2+HBP-MRC findings with surgical results. METHODS: A total of 276 donors who underwent T2 and gadoxetic acid-enhanced MRI before right hemihepatectomy for LDLT between January and December 2016 were retrospectively enrolled. Two reviewers evaluated biliary anatomy classification using T2-MRC in the first session and T2+HBP-MRC in the second session. The sensitivity, specificity, and confidence level (5-point scale) of T2-MRC and T2+HBP-MRC for variant biliary anatomy were evaluated. The agreement rates between MRC and operative cholangiography for each biliary anatomy classification and the underestimation rates for multiple bile duct openings (BDOs) for both MRC techniques were evaluated. RESULTS: Of the 276 donors, variant biliary anatomy was observed in 36.2% (100/276). T2+HBP-MRC showed a significantly higher sensitivity for diagnosing variant biliary anatomy than T2-MRC alone (99.0% [99/100] vs. 89.0% [89/100], p = 0.006), with better observer confidence level (4.9 ± 0.3 vs. 4.6 ± 0.7, p < 0.001) and inter-observer agreement (kappa, 0.902 vs. 0.730). Compared with T2-MRC alone, T2+HBP-MRC provided significantly higher agreement with operative cholangiography in biliary anatomy classification (98.6% [272/276] vs. 89.9% [248/276], p < 0.001), and significantly lower underestimation rate for multiple BDOs (5.8% [16/276] vs. 9.4% [26/276], p = 0.002). CONCLUSION: T2+HBP-MRC might be considered than T2-MRC alone, as a better depiction of biliary anatomic variations, correlated with surgical findings. KEY POINTS: •T2+HBP-MRC predicted variant biliary anatomy more accurately than T2-MRC alone. •T2+HBP-MRC might have clinical usefulness by reducing the underestimation rate of multiple bile duct openings, which requires more complicated biliary anastomoses.

Types of posterolateral corner injury associated with both bundle and selective-bundle ACL tears.

BACKGROUND: It is unknown whether a selective-bundle tear of the anterior cruciate ligament (ACL) shows a different prevalence of posterolateral corner (PLC) injury than a both-bundle tear. PURPOSE: The prevalence of injury of PLC stabilizer in relation to the type of combined ACL tear (both-bundle and selective-bundle tears) has been investigated. MATERIAL AND METHODS: This retrospective study included 94 patients who were diagnosed with an ACL tear after knee joint magnetic resonance imaging and underwent arthroscopic surgery. We compared the prevalence of each lesion in relation to the type of ACL injury and the type of selective-bundle tear. We used Fischer exact tests to compare the prevalence of each lesion in relation to the type of ACL injury and the type of selective-bundle tear. RESULTS: Both-bundle tears occurred in 55 cases (56%) and selective-bundle tears in 39 cases (44%). The most common PLC injury with an ACL tear was inferior popliteomeniscal fascicle (PMF) injury, followed by superior PMF injury. The prevalence of each PLC injury was higher for both-bundle tears than selective-bundle tears, with the exception of popliteus tendon injury diagnosed by reader 1 (P.H.J). However, these differences were statistically significant for superior PMF injury only ( p < 0.05). The prevalence of PLC injury was unrelated to the type of selective-bundle tear (anteromedial vs posterolateral). CONCLUSION: Superior PMF injury is more common in both-bundle tears than selective-bundle tears. There is no statistically significant difference in the prevalence of PLC injury between both-bundle tears and selective-bundle tears.

MR cholangiography in potential liver donors: quantitative and qualitative improvement with administration of an oral effervescent agent.

PURPOSE: To determine whether an oral effervescent agent improves magnetic resonance cholangiography (MRC) images, both qualitatively and quantitatively, in potential live liver donors. MATERIALS AND METHODS: This retrospective study was approved by the Institutional Review Board, and informed consent was waived. Seventy potential liver donors underwent 2D MRC before and after administration of an oral effervescent agent. One radiologist measured relative contrast ratio (rC) and relative signal intensity (rS) for right and left intrahepatic ducts (RHD and LHD), and common hepatic duct (CHD). After assessment of overall image quality, two other radiologists independently scored visualization of five ductal segments (RHD, LHD, CHD, cystic, and common bile duct) and assessed the preferred image set. In consensus, they assessed the biliary anatomy. The data were analyzed using a paired t-test, Wilcoxon's signed-rank test, and chi-square test. RESULTS: Both rC and rS of RHD and CHD were significantly higher on MRC images after administration of an oral effervescent agent than before (P < 0.03). The overall image quality grades and biliary visualization scores for all five duct segments were significantly higher on MRC images after administration of an oral effervescent agent than before (P < 0.0001). Between these images, both readers more often preferred MRC images with an effervescent agent rather than those without this agent (reader 1: 56/70, 80.0%; reader 2: 55/70, 78.6%; P = 0.0003). The readers correctly assessed second-order biliary tract anatomy in two more subjects on MRC after administration of an effervescent agent than before. CONCLUSION: Oral administration of an effervescent agent improves MRC images, both qualitatively and quantitatively, in live liver donors. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1656-1663.

Measurement of liver volumes by portal vein flow by Doppler ultrasound in living donor liver transplantation.

BACKGROUND: The accurate estimation of liver volume and right/left ratio in donor candidates is critical, but there is no method using portal vein (PV) flow. METHODS: Of 125 donor candidates, right/left liver volume ratio was estimated using ultrasound (US)-PV area ratio and Doppler US-PV flow ratio, and the results were compared with CT volumetry. We analyzed these results in 76 donors who underwent hemihepatectomy. We evaluated diagnostic values of Doppler US-PV flow for <30% remnant liver volume high-risk donors, and compared liver volume by Doppler US-PV flow with actual graft weight. RESULTS: In 125 donor candidates, 96.8% showed <10% difference between liver volume ratio by Doppler US-PV flow ratio and CT volumetry. Compared with CT volumetry, the mean percentage difference of liver volume ratio by Doppler US-PV flow ratio was significantly smaller than that by US-PV area ratio (±0.7% vs ±6.3%, P<.001). In 76 donors who underwent hemihepatctomy, results were similar, showing smaller mean percentage difference of liver volume ratio by Doppler US-PV flow ratio than that by US-PV area ratio (±1.0% vs ±6.0%, P<.001). Sensitivity and specificity for <30% remnant liver volume donors were 76.9% and 76.8%. Blood-free liver volume by Doppler US-PV flow was linearly correlated with graft weight (R2 =0.770, P<.001), although significantly different, with 8.5% error ratio (669.3±173.2 vs 633.7±187.1, P=.001). CONCLUSION: Doppler US-PV flow can effectively estimate right/left liver volume ratio in initial donor investigation. However, Doppler US-PV flow is not accurate in assessing donors with <30% remnant liver volume and in estimating actual graft weight.

N-butyl-2 cyanoacrylate (NBCA) embolus in the graft portal vein after portosystemic collateral embolization in liver transplantation recipient: what is the clinical significance?

Background An N-butyl-2 cyanoacrylate (NBCA) embolus in the graft portal vein was frequently observed after an intraoperative embolization of portosystemic collaterals performed to prevent portal steal in liver transplant (LT) recipients. The radiological and clinical features of NBCA emboli have not yet been described. Purpose To describe radiological and clinical features of NBCA embolus in graft portal vein after portosystemic collateral embolization in LT recipients. Material and Methods A total of 165 consecutive LT recipients who had undergone intraoperative NBCA embolization of varix were found in single institution's computerized databases of a clinical cohort of LT. Patients were evaluated for NBCA emboli (categorized into major and minor emboli according to location) on first postoperative computed tomography (CT). All electronic medical records and radiologic studies including follow-up was evaluated to determine any radiological and clinical abnormality associated with NBCA embolus. Results NBCA emboli were found in 24% (39/165) of recipients. Although most patients had minor emboli (77%, 30/39) without remarkable ultrasonography (US) abnormalities, seven (78%) of nine recipients with major emboli showed intraluminal echogenic lesions in graft portal vein on grayscale US, and five of them (71%) showed partial portal flow obstruction, although none exhibited any abnormality on contrast-enhanced US. Recipients with NBCA portal emboli showed no significant clinical abnormalities and were discharged safely. NBCA embolus eventually disappeared mostly within six months (82%, 32/39). Conclusion NBCA emboli are frequently observed after portosystemic collateral embolization in LT recipients and are not associated with poor clinical outcome. They may mimic ordinary thromboemboli on US.

Usefulness of the quantitative evaluation of diffusion-weighted mri in the diagnosis of anterior cruciate ligament tears.

PURPOSE: To evaluate the usefulness of the diffusion-weighted imaging (DWI) in the diagnosis of anterior cruciate ligament (ACL) tear using the contrast-to-noise ratio (CNR) and apparent diffusion coefficient (ADC) values according to the different b values. MATERIALS AND METHODS: Institutional review board approval was acquired. We evaluated 74 patients (M:F = 43:31, mean age of 44 years) who underwent 3.0 Tesla knee MR with DWI because of the possibility of ACL tear due to trauma. Region of interest measurements were performed. We (two radiologists) measured the signals of the DWI and derived ADC values on the oblique sagittal DWI with b values of 0, 600, and 1000. The diagnostic accuracies of the conventional MR image and each DWI with an ADC value with a different b value were evaluated. The CNR and ADC values were compared using the Mann-Whitney U-test. The diagnostic performances of the various imaging methods were evaluated using the sensitivity, specificity, and accuracy for differentiating between normal and ACL injury as determined by the use of conventional MRI with additional DWIs with McNemar test. The arthroscopic or clinical findings were used as the reference standard. RESULTS: The mean CNRs of ligament tears with b values of 600 and 1000 were significantly higher than those of normal ligament (22 versus 7 and 9 versus 4, P value < 0.05). The sensitivities and the accuracies of the DWI were significantly lower than the conventional MRIs (P value < 0.001). CONCLUSIONS: The CNRs of the torn ACL with each b value (600 and 1000) were significantly higher those of than normal ligament, although the ADC values of the torn ligament were not different from normal ligament. Addition of the DWI to the conventional MRI did not improve diagnostic performance. J. Magn. Reson. Imaging 2016;44:1116-1122.

Modified thoracolumbar injury classification and severity score (TLICS) and its clinical usefulness.

BACKGROUND: Thoracolumbar injury classification and severity score (TLICS) is not very reliable for assessment of injury to the posterior ligament complex, even when scored by experts. It is not reasonable to score every compression fracture or burst fracture the same as there is great variety in the severity of compression fractures and burst fractures. PURPOSE: To propose a modified TLICS (mTLICS) and evaluate the performance of the mTLICS system by measuring the agreement between scores determined by radiologists using both systems and actual treatment procedure delivered. MATERIAL AND METHODS: We retrospectively evaluated 134 patients with acute lumbar and thoracic spinal trauma after undergoing magnetic resonance imaging (MRI) using new mTLICS and conventional TLICS system. Inter-observer agreements of TLICS and mTLICS scores were analyzed using the kappa statistic. Nonparametric correlation analysis was used to determine correlation (R) among each score and the surgical intervention. RESULTS: The mTLICS system showed slightly higher correlation than TLICS (Rs, TLICS, 0.592 and 0.613 vs. mTLICS, 0.628 and 0.639). If we consider a total maximal score of 4 to be a negative surgical indication, mTLICS showed significantly higher sensitivities than TLICS, and if we consider a total minimal score of 4 to be a positive surgical indication, mTLICS showed significantly higher specificities than TLICS. CONCLUSION: The mTLICS score corrects deficiencies in the TLICS system that lead to ambiguity in the radiological diagnostic criteria. mTLICS is a more suitable scoring system than TLICS for predicting surgical management accurately, especially for morphological injuries.

The usefulness of gadoxetic acid-enhanced dynamic magnetic resonance imaging in hepatocellular carcinoma: toward improved staging.

PURPOSE: This study was designed to evaluate the usefulness of gadoxetic acid-enhanced dynamic magnetic resonance imaging (MRI) in staging hepatocellular carcinoma (HCC). METHODS: This study was approved by the institutional review board of our institution. Two investigators independently and retrospectively reviewed dynamic computed tomography (CT) and gadoxetic acid-enhanced dynamic MRI obtained from July to September 2011 in 195 patients with HCC (158 men, 37 women; mean age, 57.1 years). The diagnostic performances of dynamic CT and MRI were evaluated. Barcelona Clinic Liver Cancer (BCLC) stages were determined before and after gadoxetic acid-enhanced dynamic MRI and according to final diagnosis. Change in BCLC stage was evaluated after adding gadoxetic acid-enhanced dynamic MRI to dynamic CT. Diagnostic performance and BCLC staging between the two modalities were compared using the McNemar test. RESULTS: Final BCLC stage was classified as stage 0 in 25 patients (12.8%), A in 118 (60.5%), B in 33 (16.9%), C in 17 (8.7%), and D in 2 (1.0%). Compared with dynamic CT, gadoxetic acid-enhanced dynamic MRI showed significantly greater sensitivity (90.6% [203/224] vs. 79.5 % [178/224]; P < 0.0001) and significantly more accurate BCLC staging (92.8% [181/195] vs. 80.5% [157/195]; P < 0.0001). BCLC stage was changed correctly after gadoxetic acid-enhanced dynamic MRI in 13.8% (27/195) patients showing differences between CT and final BCLC stages. CONCLUSIONS: Gadoxetic acid-enhanced dynamic MRI provided important additional information compared with dynamic CT during initial staging workups in patients with HCC. Gadoxetic acid-enhanced dynamic MRI showed higher diagnostic performance and more accurate BCLC staging than dynamic CT.

Simultaneous evaluation of vascular morphology, blood volume and transvascular permeability using SPION-based, dual-contrast MRI: imaging optimization and feasibility test.

Exploiting ultrashort-T(E) (UTE) MRI, T1-weighted positive contrast can be obtained from superparamagnetic iron oxide nanoparticles (SPIONs), which are widely used as a robust T2-weighted, negative contrast agent on conventional MR images. Our study was designed (a) to optimize the dual-contrast MRI method using SPIONs and (b) to validate the feasibility of simultaneously evaluating the vascular morphology, blood volume and transvascular permeability using the dual-contrast effect of SPIONs. All studies were conducted using 3 T MRI. According to numerical simulation, 0.15 mM was the optimal blood SPION concentration for visualizing the positive contrast effect using UTE MRI (T(E) = 0.09 ms), and a flip angle of 40° could provide sufficient SPION-induced enhancement and acceptable measurement noise for UTE MR angiography. A pharmacokinetic study showed that this concentration can be steadily maintained from 30 to 360 min after the injection of 29 mg/kg of SPIONs. An in vivo study using these settings displayed image quality and CNR of SPION-enhanced UTE MR angiography (image quality score 3.5; CNR 146) comparable to those of the conventional, Gd-enhanced method (image quality score 3.8; CNR 148) (p > 0.05). Using dual-contrast MR images obtained from SPION-enhanced UTE and conventional spin- and gradient-echo methods, the transvascular permeability (water exchange index 1.76-1.77), cerebral blood volume (2.58-2.60%) and vessel caliber index (3.06-3.10) could be consistently quantified (coefficient of variation less than 9.6%; Bland-Altman 95% limits of agreement 0.886-1.111) and were similar to the literature values. Therefore, using the optimized setting of combined SPION-based MRI techniques, the vascular morphology, blood volume and transvascular permeability can be comprehensively evaluated during a single session of MR examination.

Pre-operative CT predictors associated with 30-day adverse events in patients with appendiceal inflammatory masses who underwent immediate appendectomies.

PURPOSE: To retrospectively evaluate pre-operative CT predictors that are associated with 30-day adverse events in patients who underwent immediate appendectomies for appendiceal inflammatory masses. METHODS: This retrospective study was approved by our institutional review board, and the requirement for informed consent was waived. One hundred forty-four consecutive patients who underwent immediate appendectomies and were diagnosed with appendiceal inflammatory masses by pre-operative CT from January 2005 to December 2013 at a tertiary hospital were included. The main outcome measure was 30-day adverse events. Patient demographics and data for inflammatory markers including leukocyte counts, segmented neutrophils, and C-reactive protein levels were collected by a single radiologist. Pre- and post-operative CT findings were evaluated for features of appendiceal inflammatory masses, associated findings, and post-operative adverse events by two radiologists in a blinded fashion with consensus to assess surgical and pathologic results, post-operative outcomes, and original CT interpretations. Appendiceal inflammatory masses were defined as complicated appendicitis with a phlegmon or an abscess that was identified on pre-operative CT exam. Factors associated with 30-day adverse events were assessed using logistic regression analysis. RESULTS: A total of 22 (15%) of the 144 patients (mean age [±SD] 44.6 ± 22.0 years, range 3-97 years) experienced 30-day adverse events: ten intra-abdominal abscesses, three wound infections, two cases of peritonitis, two small bowel obstructions, two intra-abdominal abscesses with peritonitis, one intra-abdominal abscess with wound infection, one intra-abdominal abscess with small bowel obstruction, and one case of peritonitis with small bowel obstruction. In univariate analysis, the presence of appendicolith (odds ratio [OR] 2.49, p = 0.048) and high-grade obstruction (OR 3.79; p = 0.01) were associated with adverse events. High-grade obstruction (adjusted OR 3.05; p = 0.04) was the only independent pre-operative predictor associated with 30-day adverse events in patients with appendiceal inflammatory masses. CONCLUSIONS: High-grade obstruction was an independent pre-operative CT predictor associated with 30-day adverse events in patients who underwent immediate appendectomies for appendiceal inflammatory masses.

Differentiation of small (≤2 cm) hepatocellular carcinomas from small benign nodules in cirrhotic liver on gadoxetic acid-enhanced and diffusion-weighted magnetic resonance images.

OBJECTIVE: To identify imaging characteristics that differentiate small (≤2 cm) HCCs from small (≤2 cm) benign nodules in cirrhotic liver on gadoxetic acid-enhanced and diffusion-weighted (DW) magnetic resonance (MR) images. MATERIALS AND METHODS: On gadoxetic acid-enhanced and DW MR images, we analysed signal intensity of 222 small HCCs and 61 benign nodules (diameter, 0.5-2 cm) at each sequence and rim enhancement during portal or equilibrium phases. Univariate and multivariate logistic regression analyses identified predictors of HCC. Combinations of significant MR findings in multivariate analysis were compared with American Association for the Study of Liver Disease (AASLD) practice guidelines. RESULTS: In multivariate analysis, arterial enhancement (adjusted odds ratio [aOR], 8.6), T2 hyperintensity (aOR, 5.8), and hyperintensity on DW images (aOR, 3.8) were significant for differentiating small HCCs from benign nodules (p ≤ 0.004). When two or all three findings were applied as diagnostic criteria for differentiating small HCCs from benign nodules, sensitivity and accuracy were significantly higher compared with AASLD practice guidelines (91% vs. 78% and 89% vs. 81%, respectively; each p < 0.0001). CONCLUSION: On gadoxetic acid-enhanced MR imaging, arterial enhancement and hyperintensity on T2-weighted and DW MR images are helpful for differentiating small HCCs from benign nodules in liver cirrhosis.

Usefulness of oblique coronal and sagittal MR images of the knee after double-bundle and selective anterior cruciate ligament reconstructions.

BACKGROUND: The use of double-bundle and selective-bundle anterior cruciate ligament (ACL) reconstruction is increasing. Few studies have been conducted to determine the diagnostic efficacy of additional oblique views of knee magnetic resonance imaging (MRI) for grading ACL graft injury for double-bundle and selective-bundle ACL reconstructions. PURPOSE: To evaluate the diagnostic value of combining oblique coronal and sagittal imaging with orthogonal views for diagnosis of ACL graft failure after double-bundle or selective-bundle ACL reconstruction. MATERIAL AND METHODS: This retrospective study included 64 patients who underwent double-bundle or selective-bundle ACL reconstruction surgery and received oblique coronal and oblique sagittal MRI of the knee. Subjective scoring of the images was performed by two radiologists who assessed the possibility of ACL graft failure based on full length view, full width view, and margin sharpness according to a 4-point scale. Diagnostic performance for ACL graft failure based on orthogonal views alone, ACL views alone, and orthogonal views with additional ACL views was evaluated by calculating the sensitivity, specificity, and accuracy. RESULTS: The full length scores and total scores on ACL views were significantly higher than those of orthogonal views. The specificities and accuracies of diagnoses were highest for a combination of orthogonal, ACL sagittal, and ACL coronal views. CONCLUSION: After double-bundle or selective-bundle ACL reconstruction, oblique sagittal and coronal images of the ACL provide better anatomic evaluation of the ACL than orthogonal views and specificity and accuracy of diagnoses were improved when oblique views were combined.

T2 relaxation times of the glenohumeral joint at 3.0 T MRI in patients with and without primary and secondary osteoarthritis.

BACKGROUND: Quantitative magnetic resonance imaging (MRI) of cartilage has recently been applied to patients with osteoarthritis (OA). T2 mapping is a sensitive method of detecting changes in the chemical composition and structure of cartilage. PURPOSE: To establish baseline T2 values of glenohumeral joint cartilage at 3.0 T and compare T2 values among subjects with and without OA. MATERIAL AND METHODS: The study involved 30 patients (18 women, 12 men; median age, 67 years; age range, 51-78 years) with primary (n = 7) and secondary OA (n = 23) in the glenohumeral joint and 34 subjects without OA (19 women, 15 men; median age, 49 years; age range, 23-63 years). All subjects were evaluated by radiography and 3.0 T MRI including a multi-echo T2-weighted spin echo pulse sequence. The T2 value of the cartilage was measured by manually drawing the region of interest on the T2 map. Per-zone comparison of T2 values was performed using Mann-Whitney U test. RESULTS: Median T2 values differed significantly between subjects without OA (36.00 ms [interquartile range, 33.89-37.31 ms]) and those with primary (37.52 ms [36.84-39.11], P = 0.028), but not secondary (36.87 ms [34.70-41.10], P = 0.160) OA. Glenohumeral cartilage T2 values were higher in different zones between patients with primary and secondary OA than in subjects without OA. CONCLUSION: These T2 values can be used for comparison to assess cartilage degeneration in patients with shoulder OA. Significant differences in T2 were observed among subjects without OA and those with primary and secondary OA.

The clinical correlation of a new practical MRI method for grading cervical neural foraminal stenosis based on oblique sagittal images.

OBJECTIVE: The purpose of this study was to determine whether each grade in a new system suggested by Park et al. (Park system) to assess cervical neural foraminal stenosis validly correlates with the associated clinical findings and to evaluate the interobserver agreement in grading between two MRI readers. MATERIALS AND METHODS: We evaluated 166 patients (98 men and 68 women; mean age, 46 years) at our institution who underwent oblique sagittal MRI of the cervical spine. Using the new Park grading system, two radiologists evaluated the MRI findings for the presence and grade of cervical neural foraminal stenosis at the most narrow point. A neurosurgeon assessed the associated clinical manifestations. A positive neurologic manifestation of the cervical neural foraminal stenosis was defined as more than one positive neurologic clinical manifestation combined with more than one positive neurologic sign. Interobserver agreements between the two radiologists were analyzed using kappa statistics. Correlation coefficients (R) to assess the relationship between the grade and neurologic manifestations were calculated with nonparametric correlation analysis (Spearman correlation). The relationship between the assigned grade and the clinical manifestations was analyzed several ways: vertebrae level (C4-5, C5-6, or C6-7) and by age group (< 46 years and ≥ 46 years). RESULTS: Among patients who were evaluated by each reader to be grade 0, only 19 (17%) and 20 patients (18%) showed positive neurologic manifestations, respectively, with most patients showing negative neurologic manifestations. Among the patients who were grade 2 and 3, one reader found all patients and the second reader found all but one patient (100% and 93%, respectively) to have positive neurologic manifestations. According to the correlation coefficients, each Park grade was moderately correlated with the associated neurologic manifestations, such that higher grades were associated with more severe clinical manifestations. If we consider grade 2 or 3 MRI findings positive for identifying positive neurologic manifestations, the sensitivities and specificities were 39.7% and 99.0% (reader 1) and 39.7% and 99.0% (reader 2), respectively. CONCLUSION: The Park system, based on oblique sagittal MRI sections, provides a reliable and reproducible assessment of the severity of cervical neural foraminal stenosis. According to the Park system, grades 2 and 3 are associated with positive neurologic manifestations, and the Park system successfully predicts positive neurologic manifestations at these grades.

Breast-specific gamma imaging: correlations with mammographic and clinicopathologic characteristics of breast cancer.

OBJECTIVE: The purpose of this article is to evaluate the correlations between breast-specific gamma imaging (BSGI) findings and mammographic and clinicopathologic characteristics of breast cancer. MATERIALS AND METHODS: Our study included 56 breast cancers that had undergone BSGI between August 2010 and December 2012. We reviewed imaging findings (BSGI and mammography) with histopathologic findings, including tumor size, histologic type, nuclear grade, presence of ductal carcinoma in situ (DCIS), and presence of extensive intraductal component (EIC); and immunochemical features, including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (ERBB2, formerly HER2), Ki67, and p53. We classified cancers into positive or negative groups on the basis of BSGI visibility and investigated the statistical differences in mammographic and histopathologic characteristics between the BSGI-positive and -negative groups. RESULTS: Among 56 malignancies, 48 (85.7%) were shown to be BSGI positive. Patients in the BSGI-positive group were statistically significantly older than those in the BSGI-negative group (p = 0.027). BSGI-positive cancers were statistically significantly larger than BSGI-negative cancers (p = 0.002). Cancers 1.0 cm or larger, unlike those of subcentimeter size, were statistically significantly more visible on BSGI (p = 0.004). The mammographic findings and mammographic densities did not statistically significantly differ between the BSGI-positive and -negative groups. Invasiveness of cancer showed no statistically significant difference on BSGI finding. Cancers with a DCIS component tended to be BSGI positive, but without statistical significance (p = 0.051). Visibility on BSGI was not statistically significantly associated with EIC, nuclear grade, ER, PR, ERBB2, Ki67, and p53. CONCLUSION: The sensitivity of BSGI for breast cancer was 85.7%. Breast cancers in older patients, cancers larger than 1.0 cm, and cancers with the DCIS component tended to be visible on BSGI. BSGI was an equally sensitive tool to detect the breast cancer in women with fatty and dense breast.

Preoperative prediction model for conversion of laparoscopic to open cholecystectomy in patient with acute cholecystitis: based on clinical, laboratory, and CT parameters.

OBJECTIVE: To identify preoperative computed tomography (CT) predictors associated with conversion from laparoscopic to open cholecystectomy and to propose the risk scoring model for prediction of conversion by integrating clinical, laboratory, and CT parameters. METHODS: The institutional review board approved this retrospective study, and informed consent was waived. One hundred eighty-three patients who underwent a laparoscopic cholecystectomy for acute cholecystitis were evaluated for clinical, laboratory, and CT parameters. Associations between conversion and these parameters were assessed by using univariate and multivariate logistic regression analysis. The risk scoring model was devised using a regression coefficient-based scoring method. RESULTS: Conversion to open cholecystectomy was performed in 30 patients (17%). Multivariate analysis identified age older than 60 years, male, and pericholecystic fluid as independent predictors of conversion. The preoperative prediction model to calculate the risk score for conversion showed sensitivity of 83% and specificity of 72%, with an area under the receiver operator curve of 0.83. CONCLUSIONS: Pericholecystic fluid collection was the only CT parameter with clinical parameters of age older than 60 years and male in prediction for conversion in acute cholecystitis. The preoperative prediction model using these 3 parameters can be adapted easily in clinical practice with a good discrimination.

Differentiation of early perforated from nonperforated appendicitis: MDCT findings, MDCT diagnostic performance, and clinical outcome.

To determine the CT findings and assess their diagnostic performance in differentiating early perforated appendicitis from nonperforated appendicitis, and to compare therapeutic approaches and clinical outcomes between two types of appendicitis. Our retrospective study was approved by our institutional review board and informed consent was waived. From July 2012 to July 2013, 339 patients [mean age 40.8 years; age range 19-80 years; 183 male (mean age 40.5 years; age range 19-79 years) and 156 female (mean age 41.2 years; age range 19-80 years)] who underwent appendectomy with preoperative CT examination for suspected acute appendicitis were included, with exclusion of 37 patients with specific CT findings for advanced perforated appendicitis. And they were categorized into nonperforated and early perforated appendicitis groups according to surgical and pathologic reports. The following CT findings were evaluated by two radiologists blinded to pathologic and surgical findings: transverse diameter of the appendix, thickness of the appendiceal wall, the depth of intraluminal appendiceal fluid, appendiceal wall enhancement, presence or absence of focal defect in the appendiceal wall, intraluminal appendiceal air, appendicolith/fecalith, periappendiceal changes, cecal wall thickening, and free fluid. The type of surgical procedures, performance of surgical drainage, and the length of hospital stay were recorded. Univariate and multivariate logistic regression analysis were used to determine the CT findings for differentiating early perforated appendicitis from nonperforated appendicitis, a total of 75 (22%) of the 339 patients was diagnosed with early perforated appendicitis. Focal wall defect [adjusted odds ratio (aOR), 23.40; p < 0.001], circumferential periappendiceal changes (aOR, 5.63; p < 0.001), appendicoliths/fecaliths (aOR, 2.47; p = 0.015), and transverse diameter of the appendix (aOR, 1.22; p = 0.003) were independently differentiating variables for early perforated appendicitis. The transverse diameter of the appendix (≥11 mm) had the highest sensitivity (62.7%) and focal wall defect in the appendiceal wall showed the highest specificity (98.8%). The prevalence of surgical drainage was higher (p = 0.001) and the mean hospital stay was approximately one day longer (p < 0.001) in the early perforated group than nonperforated group. CT can be helpful in differentiating early perforated appendicitis from nonperforated appendicitis, although the sensitivity of the evaluated findings was somewhat limited.