Prediction of Efficacy for Atezolizumab/Bevacizumab in Unresectable Hepatocellular Carcinoma with Hepatobiliary-Phase Gadolinium Ethoxybenzyl-Diethylenetriaminepentaacetic Acid MRI.

BACKGROUND: This study aimed to examine whether the coefficient of variation (CV) in the hepatobiliary-phase (HBP) of Gd-EOB-DTPA-MRI could be an independent predictive factor for tumor progression. METHODS: Patients who underwent Gd-EOB-DTPA-MRI before Atezolizumab/bevacizumab therapy at six affiliated institutions between 2018 and 2022 were included. CV for each patient was calculated as the mean value for up to five tumors larger than 10 mm, and CV of the whole tumor was calculated using LIFEx software. The tumor response was evaluated within 6-10 weeks. The primary endpoint was to investigate the predictive factors, including CV, related to tumor progression using logistic regression analysis. The secondary endpoints were tumor response rate and progression-free survival (PFS) based on CV. RESULTS: Of the 46 enrolled patients, 13 (28.3%) underwent early progressive disease. Multivariate analysis revealed that a high CV (≥0.22) was an independent predictive factor for tumor progression (p = 0.043). Patients with a high CV had significantly frequent PD than those with a low CV (43.5 vs. 13.0%, p = 0.047). Patients with a high CV tended to have shorter PFS than those with a low CV (3.5 vs. 6.7 months, p = 0.071). CONCLUSION: Quantitative analysis using CV in the HBP of Gd-EOB-DTPA-MRI may be useful for predicting tumor progression for atezolizumab/bevacizumab therapy.

Ectopic pregnancy: MRI findings and clinical utility.

PURPOSE: To assess the utility of magnetic resonance imaging (MRI) in patients with clinically suspected ectopic pregnancy (EP). METHODS: We retrospectively reviewed MRIs of 26 consecutive patients who were clinically suspected of having an EP. The diagnostic utility of MRI features of EP was analyzed retrospectively as follows: (1) Direct sign detection of ectopic gestational sac (GS); (2) Indirect signs tubal dilatation with hemosalpinx, adnexal hematoma, and hemorrhagic ascites. The diagnostic accuracy of each sign and their combination was compared to surgical records. The MRI findings of an ectopic GS were reviewed as follows: size, shape, signal intensity, and enhancement pattern. RESULTS: Of 26 patients, 24 had a tubal pregnancy; 22 of these 24 patients (92%) had a direct sign (sensitivity: 91.3%; specificity: 100%; positive predictive value: 100%). The diagnostic accuracy of the direct sign was 92%; this was more accurate than that of any single indirect sign (39%, 54%, and 50%, respectively). However, the diagnostic accuracy of EP increased to 100% when diagnostic criteria required the presence of a direct sign or at least two indirect signs. CONCLUSIONS: MRI is an effective modality for diagnosing EP with a high detection rate of extrauterine GSs. The combination of direct and indirect signs is useful for establishing the correct diagnosis.

Leydig cell tumor of the testis with characteristic contrast patterns of tumor and non-tumorous testicular parenchyma on MRI: a case report.

PURPOSE: Testicular Leydig cell tumor (LCT) is a rare subtype of testicular neoplasms that occurs in the interstitial tissue of testes, accounting for 1-3% of total testicular masses removed annually. We report a case of 70-year-old man diagnosed as testicular LCT. This report demonstrates a testicular LCT with intratumoral and non-tumorous testicular parenchymal enhancement in the affected testis, which should be considered characteristic findings of LCT. METHODS: Ultrasonography showed a hypoechoic mass. On magnetic resonance imaging, the tumor showed low signal intensity comparable to the surrounding testicular tissue on T1-weighted images (T1WI) and low signal intensity on T2-weighted images (T2WI). On gadolinium contrast-enhanced T1WI (CE-T1WI), the tumor showed a rapid and marked wash-in and subsequent prolonged washout. The spared, non-tumorous testicular parenchyma showed slow and progressive enhancement in the early phase, which was as strong as or stronger than that of the mass in the delayed phase. The patient underwent right orchiectomy. RESULTS: Pathologically, the tumor was diagnosed as a testicular Leydig cell tumor (LCT). Leydig cell proliferation was observed with well-developed microvessels, atrophy of the seminiferous tubules, and stromal edema in the non-tumorous testicular parenchyma. Leydig cells in the non-tumorous parenchyma were positive for estrogen receptors. CONCLUSION: Since the contrast findings in the non-tumorous testicular parenchymal region on CE-T1WI likely match the histopathological features of LCT, our case suggests that the presence of non-tumorous testicular parenchymal enhancement on imaging might indicate a diagnosis of LCT.

Retained placental tissue: role of MRI findings in diagnosis and clinical assessment.

OBJECTIVE: To assess the role of MRI in diagnosis and predicting clinical outcome in women with retained placental tissue. PATIENTS AND METHODS: Eleven patients with pathologically proven RPT were retrospectively studied. All underwent MRI. The following MRI parameters of RPT were studied: size, signal intensity on T1- and T2-weighted images, enhancement pattern on dynamic study, extent of attachment to the uterine myometrium, and myometrial thickness at the attachment site. Clinical reports were reviewed and MRI findings were compared with respect to outcome. RESULTS: RPT diameter varied from 30 to 102 mm. On T2-weighted images, 10 cases showed high intensity, while on T1-weighted images, seven cases showed high intensity. Nine cases were hypervascular. The myometrium was thinner at the attachment side than at the opposite side. All five cases in which RPT was delivered spontaneously showed an attachment area of less than a semicircle, hence broad attachment appears to impede detachment and necessitate additional therapy. After uterine arterial embolization, two patients showed complete infarction of RPT on enhanced MRI. CONCLUSION: MRI is useful for diagnosis and follow-up of RPT. The evaluation of extent of RPT attachment to the myometrium and vascularity on MRI can help the clinical assessment.

Evaluation of background parenchymal enhancement in breast contrast-enhanced ultrasound with Sonazoid®.

PURPOSE: The objective of this study was to retrospectively evaluate the association between background parenchymal enhancement (BPE) on contrast-enhanced ultrasound (CEUS) with Sonazoid® and patient characteristics. Additionally, background parenchymal tissues with the high-contrast effect were pathologically observed compared to those showing the low-contrast effect. METHODS: A total of 65 patients who underwent breast CEUS with Sonazoid® between January 2010 and November 2013 were enrolled. Regions of interest (ROIs) were put on the tumor and on the background parenchymal tissue. The dB values during the nonenhanced time and at peak contrast enhancement were measured based on the time intensity curve (TIC) drawn by the ROI. The differences in the dB values of pre- and post-enhanced time were obtained separately for ROIs on the tumor and ROIs on the parenchymal tissue. The patient characteristics studied were age, menstrual status, mammographic density, BPE on magnetic resonance imaging (MRI), and pathological diagnoses of breast tumors. RESULTS: There was a weak negative correlation between BPE on CEUS and age. As for the contrast effect of parenchymal tissue, there was a significant difference between the menstruating and menopausal groups. There was no significant difference among the levels of mammographic density, and among the degrees of contrast effect on MRI. BPE on CEUS was the same between those with a malignant tumor and those with a benign tumor in each menstrual status. The parenchymal tissue with the low-contrast effect showed pathological atrophy. CONCLUSION: The degree of BPE on CEUS appeared related to age, menstruating or menopausal, and atrophy of breast tissue. BPE on CEUS was the same between those with a malignant tumor and those with a benign tumor in each menstrual status.

Prototype of foot-controlled image-scrolling device for the picture archiving and communication system display interface.

Our purpose was to produce a prototype of a foot-controlled image-scrolling device that will prevent work-related upper extremity complaints by radiologists. After foot-controlled image-scrolling devices were added to a picture archiving and communication system, 15 (83%) of 18 radiologists indicated that fatigue and pain in their upper extremities were diminished. Upon further production and implementation of this image-scrolling device in radiology clinics, the new interface may help to prevent work-related injuries in radiologists.

MR findings of Lynch syndrome-related uterine endometrial carcinoma: a case report.

A 41-year-old woman presented with atypical genital bleeding. Magnetic resonance imaging demonstrated a polypoid mass from the lower uterine segment to cervical canal, approximately 32 mm in size. Additionally, a thickened sigmoid colon wall showing a markedly high signal intensity on diffusion-weighted imaging was observed. Barium enema and colonoscopy revealed a type I sigmoid colon cancer. Since this patient was relatively young and had multiple relatives with colon cancer, Lynch syndrome was suspected and proved by an immunohistochemical survey. Uterine endometrial carcinoma related to Lynch syndrome tends to occur in the lower uterine segment. Radiologists should be aware of this syndrome so that the correct diagnosis can be suggested in the imaging report.

Comparison of brain 3.0-T with 1.5-T MRI in patients with multiple sclerosis: a 6-month follow-up study.

OBJECTIVES: The 2010 revisions to the McDonald criteria for the diagnosis of multiple sclerosis (MS) were recently published. One objective of the revision was to simplify the MRI criteria. The MRI criteria do not specify magnetic field strength. We studied whether there was any difference in diagnosis between brain 3.0-T and 1.5-T MRI according to the 2010 revisions of the McDonald criteria. PATIENTS AND METHODS: We prospectively studied brain 3.0-T and 1.5-T MRI in 22 patients with MS. 1.5-T MRI was performed 24h after 3.0-T MRI, and the scanning protocol included contiguous axial sections of T2-weighted images (T2WI), T1WI, and enhanced T1WI. These two different MRI and neurological assessments were scheduled to be repeated 3 and 6 months after study entry. RESULTS: The regions where MS lesions were better visualized on 3.0-T MRI tended to be in deep white matter on T2WI. Dissemination of lesions in space and time was similar for 3.0-T and 1.5-T MRI. CONCLUSION: Our study found no difference between brain 3.0-T and 1.5-T MRI. There was no apparent impact of brain 3.0-T MRI on the diagnosis of MS according to the 2010 version of the MRI criteria.

MR signal changes on hepatobiliary imaging after oral ingestion of manganese chloride tetrahydrate: preliminary examination.

PURPOSE: To clarify magnetic resonance (MR) signal changes during hepatobiliary imaging after oral ingestion of manganese chloride tetrahydrate (Bothdel Oral Solution 10) (MCT). MATERIALS AND METHODS: Subjects were an MCT phantom, 10 healthy volunteers and 155 consecutive patients. The phantom study evaluated the relationship between MCT concentration and MR signal intensity. The volunteer study qualitatively and quantitatively analyzed the time course of hepatobiliary imaging immediately and 30, 60, 120 and 180 min after oral ingestion of MCT. The clinical study analyzed the incidence and factors affecting signal changes on additional MRCP with MCT as a final scan during routine clinical MRCP. RESULTS: In the phantom study, a significant and excellent positive linear correlation was found between MCT concentration and R2* measurement (r(2) = 0.996, p < 0.01). In the volunteer study, biliary imaging and hepatic R2* values changed significantly after oral ingestion of MCT (p < 0.05). In the clinical study, a signal drop on MRCP with MCT was visually confirmed in 14.8 % of cases. Multivariate logistic regression found no factors significantly affecting signal drop. CONCLUSION: We recommend performing MRCP early after oral ingestion of MCT, because signal changes occur even during routine MRCP.

Visualization of ovarian tumors using 3T MR imaging: diagnostic effectiveness and difficulties.

PURPOSE: We evaluated the diagnostic effectiveness of magnetic resonance (MR) imaging at 3 tesla to visualize ovarian tumors and problems associated with its use. MATERIALS AND METHODS: From the records of 423 consecutive women who underwent pelvic MR imaging using a 3T system from April 2009 to June 2010, we analyzed 50 continuous cases of ovarian tumors proved by histopathology. We evaluated visualization of these tumors for image quality and artifacts using 5-point scales. For qualitative assessment, we scored overall image quality (1, poor, to 5, excellent), degree of conviction regarding the diagnosis (1, undiagnosable, to 5, diagnosable with high certainty), and 4 representative artifacts (penetrating, chemical shift, motion, and susceptibility artifact) (1, severe, to 5, little degradation). We also retrospectively reviewed the diagnostic features of the ovarian tumors and preoperative diagnostic accuracy. For quantitative assessment, we determined tumor size and ADC value. RESULTS: Overall quality score was scored 4.9±0.5, and conviction regarding diagnosis was 4.9±0.3. Artifacts caused little degradation in most cases: penetrating, 4.8±0.5; chemical shift, 4.3±0.5; motion, 4.6±0.6; and susceptibility, 3.8±0.9. Preoperative diagnostic accuracy was 92% (sensitivity 94.7%, specificity 90.3%). Mean tumor diameter was 88.3±61 mm. The mean ADC value was 1.04±0.3 in malignant tumors and 1.15±0.5 (×10⁻6 mm²/s) in benign tumors. CONCLUSION: The quality of ovarian tumor images obtained with a 3T MR imaging system is adequate for diagnosis, with only slight degradation from penetrating or susceptibility artifacts.

Branching pattern of lenticulostriate arteries observed by MR angiography at 3.0 T.

PURPOSE: We hypothesized that the pattern of branching of the lenticulostriate arteries (LSAs) is involved in the variation of the distribution of the infarction within the LSA region. Our purpose was to evaluate the visibility of LSAs in 3D time-of-flight (TOF) MR angiography (MRA) with a 3.0 T scanner and to investigate the branching patterns of LSAs. MATERIALS AND METHODS: We performed 3D TOF MRA at 3.0 T for 100 healthy subjects. We assessed the number of LSAs and the number of branches arising from each LSA by evaluating MRA source images. RESULTS: In 200 hemispheres, 330 LSAs were visualized (mean = 1.65/hemisphere). In 3.5% of all hemispheres, no LSA was depicted; one LSA was depicted in 39%, two in 46.5%, and three in 11%. The maximum number of depicted LSA branches was five in 2% of all subjects, four in 7%, three in 26%, and two in 49% (mean = 2.3/subject). A large LSA trunk with three or more branches was found in 35% of subjects. CONCLUSION: Visualization of LSAs was possible in 96.5% of subjects by use of 3.0 T MRA. LSA branching patterns were variable, and a large LSA trunk with three or more branches was common.

[A case of ovarian cystadenofibroma with papillary projections showing very high signal intensity on T2-weighted images].

Cystadenofibromas are rare benign or borderline malignant neoplasms containing both epithelial and stromal components. We report a case of endometrioid cystadenofibroma in a patient with endometriosis. In this case, the solid component showed very high signal intensity on T2-weighted images and was enhanced after Gd-DTPA administration, reflecting marked stromal edema of fibrous tissue. Endometrial cysts with malignant transformation are reported to have an enhancing solid component and to show various intensities on T2-weighted imaging. However, a solid component showing very high signal intensity on T2-weighted images should also be considered stromal edema in benign or borderline cystadenofibromas.