Reactive lymphoid hyperplasia of the liver:Perinodular enhancement on contrast-enhanced computed tomography and magnetic resonance imaging

We report the case of a 69-year-old woman with reactive lymphoid hyperplasia(RLH) of the liver.She underwent partial hepatectomy under a preoperative diagnosis of hepatocellular carcinoma; however,histopathological analysis revealed RLH.The liver nodule showed the imaging feature of perinodular enhancement in the arterial dominant phase on contrast-enhanced computed tomography and magnetic resonance imaging,which could be a useful clue for identifying RLH in the liver.Histologically,the perinodular enhancement was compatible with prominent sinusoidal dilatation surrounding the liver nodule.

Liver metastases:Contrast-enhanced ultrasound compared with computed tomography and magnetic resonance

The development of ultrasound contrast agents with excellent tolerance and safety profiles has notably improved liver evaluation with ultrasound(US)for several applications,especially for the detection of metastases.In particular,contrast enhanced ultrasonography(CEUS)allows the display of the parenchymal microvasculature,enabling the study and visualization of the enhancement patterns of liver lesions in real time and in a continuous manner in all vascular phases,which is similar to contrast-enhanced computed tomography(CT)and contrast-enhanced magnetic resonance imaging.Clinical studies have reported that the use of a contrast agent enables the visualization of more metastases with significantly improved sensitivity and specificity compared to baseline-US.Furthermore,studies have shown that CEUS yields sensitivities comparable to CT.In this review,we describe the state of the art of CEUS for detecting colorectal liver metastases,the imaging features,the literature reports of metastases in CEUS as well as its technique,its clinical role and its potential applications.Additionally,the updated international consensus panel guidelines are reported in this review with the inherent limitations of this technique and best practice experiences.

Multiphase convolutional dense network for the classification of focal liver lesions on dynamic contrast-enhanced computed tomography

BACKGROUND The accurate classification of focal liver lesions(FLLs)is essential to properly guide treatment options and predict prognosis.Dynamic contrast-enhanced computed tomography(DCE-CT)is still the cornerstone in the exact classification of FLLs due to its noninvasive nature,high scanning speed,and high-density resolution.Since their recent development,convolutional neural network-based deep learning techniques has been recognized to have high potential for image recognition tasks.AIM To develop and evaluate an automated multiphase convolutional dense network(MP-CDN)to classify FLLs on multiphase CT.METHODS A total of 517 FLLs scanned on a 320-detector CT scanner using a four-phase DCECT imaging protocol(including precontrast phase,arterial phase,portal venous phase,and delayed phase)from 2012 to 2017 were retrospectively enrolled.FLLs were classified into four categories:Category A,hepatocellular carcinoma(HCC);category B,liver metastases;category C,benign non-inflammatory FLLs including hemangiomas,focal nodular hyperplasias and adenomas;and category D,hepatic abscesses.Each category was split into a training set and test set in an approximate 8:2 ratio.An MP-CDN classifier with a sequential input of the fourphase CT images was developed to automatically classify FLLs.The classification performance of the model was evaluated on the test set;the accuracy and specificity were calculated from the confusion matrix,and the area under the receiver operating characteristic curve(AUC)was calculated from the SoftMax probability outputted from the last layer of the MP-CDN.RESULTS A total of 410 FLLs were used for training and 107 FLLs were used for testing.The mean classification accuracy of the test set was 81.3%(87/107).The accuracy/specificity of distinguishing each category from the others were 0.916/0.964,0.925/0.905,0.860/0.918,and 0.925/0.963 for HCC,metastases,benign non-inflammatory FLLs,and abscesses on the test set,respectively.The AUC(95%confidence interval)for differentiating each category from the others was 0.92(0.837-0.992),0.99(0.967-1.00),0.88(0.795-0.955)and 0.96(0.914-0.996)for HCC,metastases,benign non-inflammatory FLLs,and abscesses on the test set,respectively.CONCLUSION MP-CDN accurately classified FLLs detected on four-phase CT as HCC,metastases,benign non-inflammatory FLLs and hepatic abscesses and may assist radiologists in identifying the different types of FLLs.

Differentiation of pyogenic hepatic abscesses from malignant mimickers using multislice-based texture acquired from contrast-enhanced computed tomography

BACKGROUND： Pyogenic hepatic abscess may mimic primary or secondary carcinoma of the liver on contrast-enhanced computed tomography（CECT）. The present study was to explore the usefulness of the analysis of multislice-based texture acquired from CECT in the differentiation between pyogenic hepatic abscesses and malignant mimickers.METHODS： This retrospective study included 25 abscesses in 20 patients and 33 tumors in 26 subjects who underwent CECT. To make comparison, we also enrolled 19 patients with hepatic single simple cyst. The images from CECT were analyzed using a Laplacian of Gaussian band-pass filter（5 filter levels with sigma weighting ranging from 1.0 to 2.5）. We also quantified the uniformity, entropy, kurtosis and skewness of the multislice-based texture at different sigma weightings. Statistical significance for these parameters was tested with oneway ANOVA followed by Tukey honestly significant difference（HSD） test. Diagnostic performance was evaluated using the receiver operating characteristic（ROC） curve analysis.RESULTS： There were significant differences in entropy and uniformity at all sigma weightings（P〈0.001） among hepatic abscesses, malignant mimickers and simple cysts. The significant difference in kurtosis and skewness was shown at sigma 1.8 and 2.0 weightings（P=0.002-0.006）. Tukey HSD testshowed that the abscesses had a significantly higher entropy and lower uniformity compared with malignant mimickers（P=0.000-0.004）. Entropy（at a sigma 2.0 weighting） had the largest area under the ROC curve（0.888） in differentiating abscesses from malignant mimickers, with a sensitivity of 81.8% and a specificity of 88.0% when the cutoff value was set to 3.64.CONCLUSION： Multislice-based texture analysis may be useful for differentiating pyogenic hepatic abscesses from malignant mimickers.

Assessing no-surgical treatment response in bronchogenic carcinoma with contrast material-enhanced computed tomography

Objective:The aim of the study was to evaluate the efficacy of contrast material-enhanced computed tomography(CT) in assessing no-surgical treatment response in bronchogenic carcinoma.Methods:The 67 patients with bronchogenic carcinoma after no-surgical treatment underwent two-phase contrast material-enhanced computed tomography.Two spiral CT scans were obtained at 25 and 90 s respectively after nonionic contrast material was administrated via the antecubital vein at a rate of 4 mL/s by using an autoinjector.Precontrast and postcontrast attenuation values on every scan were recorded and peak height was calculated.Enhancement pattern was evaluated on the image obtained at 25 and 90 s after injection of contrast medium.Results:Precontrast attenuation value,postcontrast attenuation values at 25 and 90 s were(41.26 ± 7.77) Hu,(56.45 ± 10.48) Hu,(70.82 ± 11.99) Hu,respectively.No statistically significant difference in precontrast attenuation was found between our results in this study and the results in our old study(mean precontrast attenuation 40.70 Hu) which was obtained in cases without any therapy(t = 0.593,P = 0.555﹥0.05).Peak height of bronchogenic carcinoma after no-surgical treatment [(29.40 ± 10.73) Hu] were significantly lower than that of bronchogenic carcinoma without any therapy obtained in our old study(mean peak height 35.79 Hu)(t =-4.874,P = 0.001 < 0.05).The 39 among 67 cases appeared homogeneous enhancement at 90 s.At 25 s,there were 26 cases with inhomogeneous enhancement,9 cases with homogeneous enhancement,2 cases with central enhancement,and 2 cases with peripheral enhancement among the 39 cases.Conclusion:Peak heights can reflect the blood supply of bronchogenic carcinoma and might be an index for evaluation of no-surgical treatment response in bronchogenic carcinoma.

Hepatic focal nodular hyperplasia in children:Imaging features on multi-slice computed tomography

AIM:To retrospectively analyze the imaging features of hepatic focal nodular hyperplasia(FNH) in children on dynamic contrast-enhanced multi-slice computed tomography(MSCT) and computed tomography angiography(CTA) images.METHODS:From September 1999 to April 2012,a total of 218 cases of hepatic FNH were confirmed by either surgical resection or biopsy in the Sun Yat-sen Memorial Hospital of Sun Yat-sen University and the Cancer center of Sun Yat-sen University,including 12 cases(5.5%) of FNH in children(age ≤ 18 years old).All the 12 pediatric patients underwent MSCT.We retrospectively analyzed the imaging features of FNH lesions,including the number,location,size,margin,density of FNH demonstrated on pre-contrast and contrastenhanced computed tomography(CT) scanning,central scar,fibrous septa,pseudocapsule,the morphology of the feeding arteries and the presence of draining vessels(portal vein or hepatic vein).RESULTS:All the 12 pediatric cases of FNH had solitary lesion.The maximum diameter of the lesions was 4.0-12.9 cm,with an average diameter of 5.5 ± 2.5 cm.The majority of the FNH lesions(10/12,83.3%) had well-defined margins.Central scar(10/12,83.3%) and fibrous septa(11/12,91.7%) were commonly found in children with FNH.Central scar was either isodense(n = 7) or hypodense(n = 3) on pre-contrast CT images and showed progressive enhancement in 8 cases in the equilibrium phase.Fibrous septa were linear hypodense areas in the arterial phase and isodense in the portal and equilibrium phases.Pseudocapsule was very rare(1/12,8.3%) in pediatric FNH.With the exception of central scars and fibrous septa within the lesions,all 12 cases of pediatric FNH were homogenously enhanced on the contrast-enhanced CT images,significantly hyperdense in the arterial phase(12/12,100.0%),and isodense in the portal venous phase(7/12,58.3%) and equilibrium phase(11/12,91.7%).Central feeding arteries inside the tumors were observed on CTA images for all 12 cases of FNH,whereas no neovascularization of malignant tumors was noted.In 9 cases(75.0%),there was a spoke-wheel shaped centrifugal blood supply inside the tumors.The draining hepatic vein was detected in 8 cases of pediatric FNH.However,the draining vessels in the other 4 cases could not be detected.No associated hepatic adenoma or hemangioma was observed in the livers of the 12 pediatric cases.CONCLUSION:The characteristic imaging appearances of MSCT and CTA may reflect the pathological and hemodynamic features of pediatric FNH.Dynamic multi-phase MSCT and CTA imaging is an effective method for diagnosing FNH in children.

Enhancement patterns of small hepatocellular carcinoma shown by dynamic MRI and CT

Objectives: To study prospectively the enhancement features of small hepatocellular carcinoma (SHCC) with multi-phase scanning of dynamic MRI and spi- ral CT, and discuss the superiority of dynamic MRI to spiral CT. Methods: Multi-phase dynamic contrast scanning of high field MRI and spiral CT were performed in 53 patients with SHCC. The arterial phase, portal ve- nous phase and delayed phase scanning of spiral CT was done after the pre-contrast scanning of the entire liver. MRI was performed with SE sequence and fast multiplanar spoiled gradient-recalled sequence dy- namic multi-phase contrast scanning. Results: Seventy-six lesions were found in all 53 pa- tients. Sixty-nine and 54 of the 76 lesions enhanced obviously in MRI and spiral CT arterial phase scan- ning respectively. The typical enhancement patterns of SHCC in the arterial phase, portal venous phase and delayed phase scanning of MRI and spiral CT were hyper-hypo-hypointense (dense) and hyper-iso- hypointense (dense). Atypical enhancement patterns were hyper-hyper-hyperintense (dense), hyper-iso- isointense (dense) and hypo-hypo-hypointense (dense). Conclusions: Both MRI and spiral CT multi-phase dynamic contrast-enhanced scanning could demon- strate the enhancement features of SHCC, and arte- rial phase scan of MRI was superior to spiral CT in reflecting the hypervascular characterization of SHCC. In addition, MRI was better than spiral CT in characterization of hepatic lesions combined with SE sequence.

Contrast-enhanced ultrasonography in the evaluation of incidental focal liver lesions: A cost-effectiveness analysis

AIM To determine whether contrast-enhanced ultrasonography(CEUS) as the first-line method is more costeffective in evaluating incidentally discovered focal liver lesions(FLLs) than is computed tomography(CT) and magnetic resonance imaging(MRI). METHODS Between 2010 and 2015, our prospective study enrolled 459 patients with incidentally found FLLs. The biological nature of FLLs was assessed by CEUS in all patients. CT or MRI examinations were added in unclear cases. The sensitivity and specificity of CEUS were calculated. The total costs of CEUS examinations and of the added examinations performed in inconclusive cases were calculated. Afterwards, the theoretical expenses for evaluating incidentally discovered FLLs using CT or MRI as the first-line method were calculated. The resultswere compared. RESULTS The total cost of the diagnostic process using CEUS for all enrolled patients with FLLs was 75884 USD. When the expenses for additional CT and MRI examinations performed in inconclusive cases were added, the total cost was 90540 US dollar(USD). If all patients had been examined by CT or MR as the first-line method, the costs would have been 78897 USD or 384235 USD, respectively. The difference between the cost of CT and CEUS was 3013 USD(4%) and that between MRI and CEUS was 308352 USD(406.3%). We correctly described 97.06% of benign or malignant lesions, with 96.99% sensitivity and 97.09% specificity. Positive predictive value was 94.16% and negative predictive value was 98.52%. In cases with 4 and more lesions, malignancy is significantly more frequent and inconclusive findings significantly less frequent(P < 0.001).CONCLUSION While the costs of CEUS and CT in evaluating FLLs are comparable, CEUS examination is far more costeffective in comparison to MRI.

Adaptive enhancement design of triply periodic minimal surface lattice structure based on non-uniform stress distribution

The Schwarz primitive triply periodic minimal surface(P-type TPMS)lattice structures are widely used.However,these lattice structures have weak load-bearing capacity compared with other cellular structures.In this paper,an adaptive enhancement design method based on the non-uniform stress distribution in structures with uniform thickness is proposed to design the P-type TPMS lattice structures with higher mechanical properties.Two types of structures are designed by adjusting the adaptive thickness distribution in the TPMS.One keeps the same relative density,and the other keeps the same of non-enhanced region thickness.Compared with the uniform lattice structure,the elastic modulus for the structure with the same relative density increases by more than 17%,and the yield strength increases by more than 10.2%.Three kinds of TPMS lattice structures are fabricated by laser powder bed fusion(L-PBF)with 316L stainless steel to verify the proposed enhanced design.The manufacture-induced geometric deviation between the as-design and as-printed models is measured by micro X-ray computed tomography(μ-CT)scans.The quasi-static compression experimental results of P-type TPMS lattice structures show that the reinforced structures have stronger elastic moduli,ultimate strengths,and energy absorption capabilities than the homogeneous P-TPMS lattice structure.

Transition to computed radiography： can emergency medicine doctors accurately predict the need of film printing to facilitate optimal patient care？

BACKGROUND： This study aimed to evaluate emergency medicine doctors＇ accuracy in predicting the need of film printing in a simulated setting of computed radiography and assess whether this can facilitate optimal patient care.METHODS： Cross sectional study was conducted from 20 March 2009 to 3 April 2009 in 1334 patients. After clinical assessment of those patients who needed X-ray examination, doctors in the emergency department would indicate whether film printing was necessary for subsequent patient care in a simulated computed radiography setting. The fi nal discharge plan was then retrieved from each patient record. Accuracy of doctors＇ prediction was calculated by comparing the initial request for radiographic film printing and the final need of film. Doctors with different level of emergency medicine experience would also be analyzed and compared.RESULTS： The sensitivity of predicting fi lm printing was 84.5% and the specifi city of predicting no fi lm printing was 91.2%. Positive predictive value was 88.4% while negative predictive value was 88.2%. The overall accuracy was 88.2%. The accuracy of doctors stratified into groups of fellows, higher trainees and basic trainees were 85.4%, 90.5% and 88.5% respectively （P=0.073）.CONCLUSIONS： Our study showed that doctors can reliably predict whether film printing is needed after clinical assessment of patients, before actual image viewing. Advanced indication for film printing at the time of imaging request for selected patients can save time for all parties with minimal wastage.

Preliminary assessing no-surgical treatment response in bronchogenic carcinoma with changes in enhancement pattern

Objective： The aim of this study was to evaluate the efficacy of changes in enhancement pattern in assessing no-surgical treatment response in bronchogenic carcinoma preliminarily. Methods Thirty-three patients with bronchogenic carcinoma underwent two-phase contrast material-enhanced computed tomography prior to and after stopping no-surgical treatment more than one-month respectively. Two spiral CT scans were obtained at 25 and 90 s respectively after nonionic contrast material was administrated via the antecubital vein at a rate of 3 mL/s by using an autoinjector. The sum of the tumor longest diameters （LD） prior to treatment, after treatment and the sum of the post-treatment tumor enhancement area LD on the images obtained at 90 s after injection of contrast medium were recorded, Precontrast and postcontrast attenuation on every scan was recorded and peak height was calculated. The significance of the difference among groups was analyzed by means of ANOVA, student t test and chi-square test. Results： The sum of the tumor LD prior to treatment, that of after treatment and the sum of the post-treatment tumor enhancement area LD on the images obtained at 90 s after injection of contrast medium were （4.49 ± 1.32）, （4.05 ± 1.63）, （3.36 ± 1.22） cm respectively and there were statistically significant dif- ferences among them （f= 5.467, P = 0.006）. The sum of the tumor LD prior to treatment was significantly higher than that of the post-treatment tumor enhancement area （P = 0.001）. No statistically significant difference in the sum of the tumor LD was found between the pre- treatment and the post-treatment （P = 0.207）. There was no statistically significant difference between the sum of the tumors LD and that of tumor enhancement area after treatment （P = 0.086）. The response rate （RR） （21.21%） according to changes in sum of the tumor LD was significantly lower than that （30.30%） according to changes in the sum of the post-treatment tumor enhancement area LD （x2 = 15.12, P 〈 0.05）, and the progressive diseases （PD） rate （21.21%） was significantly higher than that （12.12%; X2 = 14.12, P 〈 0.05）. No statistically significant difference was found between precontrast attenuation prior to treatment [（41.77±7.03） HU] and that after treatment [（41.89 ± 7.63） HU; t = 0.335, P = 0.740 〉 0.05]. Peak height of bronchogenic carcinoma prior to treatment [（36.50 ± 11.21） HU] were significantly higher than that after treatment [（29.91 ± 10.35） HU; t = 10.081, P = 0.001]. Conclusion： Therapeutic effect may be underestimated with use of changes in sum of the tumor LD. The changes in sum of tumor enhancement area LD in addition to peak height is suggested to be used in assessing no-surgical.treatment response in bronchogenic carcinoma.

Enhancement characteristics of the hepatic parenchyma in CT scanning during splenoportography

Objective: To evaluate the enhancement characteristics of the hepatic parenchyma during scanning with computed tomography (CT) during splenoportography (CTSP). Methods: Thirty patients refferred for CTSP were included in the study. Attenuation was measured at different time after contrast medium injection, and time-attenuation curves were created. Enhancement characteristics were evaluated, and the parenchyma-to-tumor difference of attenuation were compared. Results: CTSP led to high parenchymal enhancement. The highest enhancement value in the left lobe was (218. 0±53. 2) Hu and (246. 0±60. 2) Hu in the right lobe. The difference between the right and left lobes was statistically significant (P<0. 05); The parenchyma-to-tumor difference of (65. 3±25. 6) Hu was observed during scanning after injection. Conclusion: The high levels of liver parenchymal enhancement and parenchyma-to-lesion contrast can be achieved within the scanning time with CTSP.

Epithelioid angiomyolipoma of the liver:Cross-sectional imaging findings of 10 immunohistochemically-verified cases

AIM： To retrospectively evaluate the computed tomography （CT）/magnetic resonance imaging （MRI） imaging features of epithelioid angiomyolipoma of the liver （Epi-HAML）, with pathology as a reference. METHODS： The CT/MRI findings （number, diameter, lobar location, and appearance of lesions） in a series of 10 patients with 12 pathologically proven epithelioid angiomyolipomas of the liver were retrospectively analyzed. The imaging features, including attenuation/ signal intensity characteristics, presence of fat, hypervascular, outer rim, and vessels within lesion, were evaluated and compared with that of non-Epi- HAML in 11 patients （13 lesions）. The Fisher exact test was used to compare difference in probability of imaging features between the two types. RESULTS： For 21 patients, CT images of 15 patients and MR images of six patients were available. No patient underwent two examinations. For the 15 patients with a CT scan, all HAML lesions in the two groups （10 Epi-HAML and seven non-Epi-HAML） manifested as hypoattenuation. For the six patients with MRI, all lesions （two Epi-HAML and six non-Epi- HAML） were hypointense on TlWI （fat suppression） and hyperintense on T2WI. There were 10 non-Epi-HAML, but only two Epi-HAML lesions showed the presence of fat, which significantly different between the two types （P = 0.005）. On the dynamic contrast enhancement （DCE） imaging, eight Epi-HAML, and 13 non-Epi lesions manifested as hypervascular. Punctate or curved vessels were displayed in 10 Epi-HAML as well as in nine non- Epi lesions and outer rim enhancement could be found with eight Epi-HAML as well as six non-Epi lesions. CONCLUSION： Little or no presence of adipose tissue was found to be an imaging feature of Epi- HAML, compared with the non-Epi type. In addition, hypervascularity with opacification of central punctiform or filiform vessels on DCE would be a characteristic enhancement pattern for Epi-HAML.

Perivascular epithelioid cell tumor of the liver:A report of two cases and review of the literature

Perivascular epithelioid cell tumor (PEComa) is a rare tumor which arises from mesenchymal tissues. It is predominant in the uterus,but very rare in the liver. To the best of our knowledge,less than 5 cases of PEComa of the liver have been reported. Herein we present two pathologically proven cases of PEComa of the liver,retrospectively analyze their clinical and imaging features,and review the literature.

Contrast ultrasound in hepatocellular carcinoma at a tertiary liver center: First Indian experience

AIM: To assess the role of contrast enhanced ultrasonography in evaluation of hepatocellular carcinoma (HCC) at the first Indian tertiary liver center. METHODS: Retrospective analysis of contrast enhanced ultrasound (CEUS) examinations over 24 mo for diagnosis, surveillance, characterization and follow up of 50 patients in the context of HCC was performed. The source and indication of referrals, change in referral rate, accuracy and usefulness of CEUS in a tertiary liver center equipped with a 64 slice dual energy computer tomography (CT) and 3 tesla magnetic resonance imaging (MRI) were studied. Sonovue (BR1, Bracco, Italy, a second generation contrast agent) was used for contrast US studies. Contrast enhanced CT/MRI or both were performed in all patients. The findings were taken as a baseline reference and correlation was done with respect to contrast US. Contrast enhanced MRI was performed using hepatocyte specific gadobenate dimeglumine (Gd-BOPTA). Iomeron (400 mg; w/v) was used for dynamic CT examinations. RESULTS: About 20 (40%) of the examinations were referred from clinicians for characterization of a mass from previous imaging. About 15 (30%) were performed for surveillance in chronic liver disease; 5 (10%) examinations were performed for monitoring lesions after radiofrequency ablation (RFA); 3 (6%) were post trans-arterial chemoembolization (TACE) assessments and 3 (6%) were patients with h/o iodinated contrast allergy. About 2(4%) were performed on hemodynamically unstable patients in the intensive care with raised alpha fetoprotein and 2(4%) patients were claustrophobic. The number of patients referred from clinicians steadily increased from 12 in the first 12 mo of the study to 38 in the last 12 mo. CEUS was able to diagnose 88% of positive cases of HCC as per reference standards. In the surveillance group, specificity was 53.3% vs 100% by CT/MRI. Post RFA and TACE specificity of lesion characterization by CEUS was 100% in single/large mass assessment, similar to CT/MRI. For non HCC lesions such as regenerative and dysplastic nodules, the specificity was 50% vs 90% by CT/MRI. The positive role of CEUS in imaging spectrum of HCC included a provisional urgent diagnosis of an incidentally detected mass. It further led to a decrease in time for further management. A confident diagnosis on CEUS was possible in cases of characterization of an indeterminate mass, in situations where the patient was unfit for CT/MRI, was allergic to iodinated contrast or had claustrophobia, etc.CEUS was also cost effective, radiation free and an easy modality for monitoring post RFA or TACE lesions. CONCLUSION: CEUS is a valuable augmentation to the practice of ultrasonography, and an irreplaceable modality for confounding cases and interpretation of indeterminate lesions in imaging of HCC.

Perfusion CT findings in liver of patients with tumor during chemotherapy

AIM: To investigate the microcirculation changes in liver of patients with tumor during chemotherapy by perfusion computed tomography (CT). METHODS: Sixty patients with tumor and 20 controls were enrolled in this study. Perfusion CT parameters of patients and controls were compared, including hepatic perfusion index (HPI), mean transit time (MTT), and permeability-surface area product (PS). Correlation between perfusion CT parameters, treatment cycle and alanine aminotransferase (ALT) level was studied. RESULTS: No difference was found in HPI (25.68% ± 7.38% vs 26.82% ± 5.13%), MTT (19.67 ± 5.68 s vs21.70 ± 5.43 s) and PS (17.00 ± 4.56 mL/100 mL per min vs 19.92 ± 6.35 mL/100 mL per min) between pa- tients and controls. The HPI and MTT were significantly higher in patients undergoing 2 cycles of chemotherapy than in controls and those undergoing 1 cycle of che- motherapy (29.76% ± 5.87% vs 25.68% ± 7.38% and 25.35% ± 4.05%, and 25.61 ± 5.01 s vs 19.67 ± 5.68 s and 19.74 ± 4.54 s, respectively, P < 0.05). The HPI was higher in patients with hepatic steatosis than in controls and those without hepatic steatosis (30.85% ± 6.17% vs 25.68% ± 7.38% and 25.70% ± 4.24%, P < 0.05). Treatment cycle was well correlated with HPI and MTT (r = 0.40, r = 0.50, P < 0.01). ALT level was not correlated with perfusion CT parameters. CONCLUSION: HPI and MTT are significantly increased in patients with tumor during chemotherapy and well correlated with treatment cycle. Chemotherapy affects hepatic microcirculation in patients with tumor. Changes in hepatic microcirculation can be quantitatively assessed by perfusion CT.

Correlation between Calcified Liver Metastases and Histopathology of Primary Colorectal Carcinoma in Chinese

The study examined the association between calcified liver metastases and the histopathology of the primary colorectal carcinoma in Chinese.The clinical,pathological and CT data were retrospectively analyzed in 210 patients (mean age:54.2 years) with liver metastases from colorectal carcinoma.Plain CT scanning and contrast-enhanced scanning were performed in all the patients.For the contrast-enhanced examination,iohexol was injected by using a high pressure syringe at a flow rate of 2.5-3.0 mL/s.The arterial phase lasted approximately 25 s and the portal venous phase about 60 s.All patients had no history of chronic liver diseases and had never received interventional treatments.χ 2-test was used to analyze the rate of calcification in the liver metastasis from colorectal cancer of different differentiation degrees.Among the 210 cases of liver metastases,22 patients (10.5%) were found to have calcified liver metastases on CT scan.Two patients with calcified liver metastasis received lumpectomy and developed calcification in recurrent tumors.Another two patients had calcification in newly developed tumor masses.And the calcification in the newly developed masses was similar to that of their primary counterparts in terms of morphology and distribution.On the enhanced CT scan,the tumors exhibited no enhancement during hepatic arterial phase and showed slight rim enhancement during portal venous scan in the 22 cases.The calcification became obscure on contrast-enhanced scans.Histopathologically,the primary tumors were well-differentiated adenocarcinoma in 6 cases,moderately-differentiated adenocarcinoma in 10,poorly-differentiated adenocarcinoma in 4 and mucinous adenocarcinoma in 2 among the 22 cases.No statistical correlation was noted between the incidence of calcified liver metastasis and the pathological subtypes and differentiation degrees of the primary colorectal carcinoma.It was concluded that calcified liver metastases may result from colorectal adenocarcinomata of different differentiation degrees or mucinous adenocarcinomata in Chinese population.There is no correlation between calcification of liver metastases and the pathological subtype of the primary colorectal carcinoma in Chinese,which is different from the findings that calcified metastases were associated with colorectal mucinous adenocarcinoma in other ethnic groups.

Liver involvement in patients with COVID-19 infection:A comprehensive overview of diagnostic imaging features

During the first wave of the pandemic,coronavirus disease 2019(COVID-19)infection has been considered mainly as a pulmonary infection.However,different clinical and radiological manifestations were observed over time,including involvement of abdominal organs.Nowadays,the liver is considered one of the main affected abdominal organs.Hepatic involvement may be caused by either a direct damage by the virus or an indirect damage related to COVID-19 induced thrombosis or to the use of different drugs.After clinical assessment,radiology plays a key role in the evaluation of liver involvement.Ultrasonography(US),computed tomography(CT)and magnetic resonance imaging(MRI)may be used to evaluate liver involvement.US is widely available and it is considered the first-line technique to assess liver involvement in COVID-19 infection,in particular liver steatosis and portal-vein thrombosis.CT and MRI are used as second-and third-line techniques,respectively,considering their higher sensitivity and specificity compared to US for assessment of both parenchyma and vascularization.This review aims to the spectrum of COVID-19 liver involvement and the most common imaging features of COVID-19 liver damage.

A case of leptospirosis simulating colon cancer with liver metastases

We report a case of a 61-year-old man who presented with fatigue,abdominal pain and hepatomegaly.Computed tomography (CT) of the abdomen showed hepatomegaly and multiple hepatic lesions highly suggestive of metastatic diseases.Due to the endoscopic finding of colon ulcer,colon cancer with liver metastases was suspected.Biochemically a slight increase of transaminases,alkaline phosphatase and gammaglutamyl transpeptidase were present;α- fetoprotein,carcinoembryogenic antigen and carbohydrate 19-9 antigen serum levels were normal.Laboratory and instrumental investigations,including colon and liver biopsies revealed no signs of malignancy.In the light of spontaneous improvement of symptoms and CT findings,his personal history was revaluated revealing direct contact with pigs and their tissues.Diagnosis of leptospirosis was considered and confirmed by detection of an elevated titer of antibodies to leptospira.After two mo,biochemical data,CT and colonoscopy were totally normal.

Multislice spiral CT angiography in evaluation of liver transplantation candidates

BACKGROUND: Orthotopic liver transplantation has be- come the treatment of choice for patients with end-stage liver disease. This study was designed to study whether multislice spiral CT angiography (MSCTA) could be used for preoperative evaluation for orthotopic liver transplanta- tion candidates. METHODS: Eighty consecutive potential candidates for liver transplantation were evaluated with dual-phase three-di- mensional CT angiography (3DCTA). The arterial-phase was used to create vascular maps of the celiac axis (inclu- ding the origin of the hepatic common artery, left gastric artery and splenic artery) and origin of the superior mesen- teric artery. The portal venous-phase was used to analyze portal vein thrombosis and collateral vascularization of the portal vein. Statistical analyses were made using the chi- square test for differences between hepatic arterial anatomy of 80 patients and Michel's anatomy of 200 patients. Appearance of MSCTA and operative results of 16 patients were analyzed. RESULTS; Sixty-two patients (77.5%) showed conven- tional and 18 (22.5%) nonconventional hepatic arterial anatomy. A significant difference was found between the two groups in anatomy of the hepatic artery (P <0.05). Celiac axis stenosis was observed in 6 patients, SA aneu- rysm in 2, small-caliber hepatic arterial vessels in 2, and portal vein thrombosis in 15. Vascular structures of 16 ope- rative patients were well defined. CONCLUSION: As a noninvasive examination, MSCTA can provide a comprehensive preoperative vascular evalua- tion for liver transplantation candidates.