Soft tissue stabilization of the hinge position in medial closed wedge distal femoral osteotomy: an anatomical study.

BACKGROUND: Soft tissue has an important role in stabilizing the hinge point of medial closed wedge distal femoral osteotomy (MCWDFO). However, there are conflicting data on the soft tissue anatomy around the hinge point of MCWDFO and, therefore, further anatomical data are needed. The purposes of the study were to: 1) anatomically analyze the soft tissue around the hinge point of MCWDFO; 2) radiologically define the appropriate hinge point to prevent an unstable hinge fracture based on the result of the anatomical analysis; and 3) histologically analyze the soft tissue based on the result of the anatomical analysis. METHODS: In 20 cadaveric knees, the capsule attachment of the distal lateral side of the femur was marked with a radiopaque ball bearing. A digital planning tool was used to calculate the area of the marked capsule attachment around the ideal hinge point of MCWDFO on radiographs. The soft tissue around the hinge point was histologically examined and the periosteal thickness was measured and visualized graphically. The graph and radiograph were overlayed using image editing software, and the appropriate hinge position was determined based on the periosteal thickness. RESULTS: As a result, the periosteal thickness of the distal lateral femur tended to rapidly decrease from the metaphyseal region toward the diaphyseal region. The overlayed graph and radiograph revealed that the periosteal thickness changed in the region corresponding to the apex of the turning point of the femoral metaphysis in all cases. CONCLUSIONS: In conclusion, the periosteum might support the hinge of MCWDFO within the area surrounded by the apex of the turning point of the femoral metaphysis and the upper border of the posterior part of the lateral femoral condyle.

[Influence of Image Reconstruction Method on Image Quality in Digital Breast Tomosynthesis].

PURPOSE: Digital breast tomosynthesis (DBT) imaging uses two types of image reconstruction. methods, i.e., filtered back projection (FBP) method and an iterative reconstruction (IR) method. Although the effect of the difference in the image reconstruction method on the image quality has been reported, these studies were performed using different apparatus or conditions. In this study, we examined the effect of image reconstruction on the image quality using the same equipment under the same conditions. METHOD: We measured reflection artifact, sharpness, signal detection ability, and granularity using DBT-photographed images by both the FBP and the IR methods. RESULT: Although the difference between the two methods was subtle for granularity, IR was found to be superior to FBP in all items tested. CONCLUSION: This study suggested the clinical usefulness of IR over FBP.

Consensus report from the 8th International Forum for Liver Magnetic Resonance Imaging.

OBJECTIVES: The 8th International Forum for Liver Magnetic Resonance Imaging (MRI), held in Basel, Switzerland, in October 2017, brought together clinical and academic radiologists from around the world to discuss developments in and reach consensus on key issues in the field of gadoxetic acid-enhanced liver MRI since the previous Forum held in 2013. METHODS: Two main themes in liver MRI were considered in detail at the Forum: the use of gadoxetic acid for contrast-enhanced MRI in patients with liver cirrhosis and the technical performance of gadoxetic acid-enhanced liver MRI, both opportunities and challenges. This article summarises the expert presentations and the delegate voting on consensus statements discussed at the Forum. RESULTS AND CONCLUSIONS: It was concluded that gadoxetic acid-enhanced MRI has higher sensitivity for the diagnosis of hepatocellular carcinoma (HCC), when compared with multidetector CT, by utilising features of hyperenhancement in the arterial phase and hypointensity in the hepatobiliary phase (HBP). Recent HCC management guidelines recognise an increasing role for gadoxetic acid-enhanced MRI in early diagnosis and monitoring post-resection. Additional research is needed to define the role of HBP in predicting microvascular invasion, to better define washout during the transitional phase in gadoxetic acid-enhanced MRI for HCC diagnosis, and to reduce the artefacts encountered in the arterial phase. Technical developments are being directed to shortening the MRI protocol for reducing time and patient discomfort and toward utilising faster imaging and non-Cartesian free-breathing approaches that have the potential to improve multiphasic dynamic imaging. KEY POINTS: • Gadoxetic acid-enhanced MRI provides higher diagnostic sensitivity than CT for diagnosing HCC. • Gadoxetic acid-enhanced MRI has roles in early-HCC diagnosis and monitoring post-resection response. • Faster imaging and free-breathing approaches have potential to improve multiphasic dynamic imaging.

Three-dimensional spin-echo-based black-blood MRA in the detection of vasospasm following subarachnoid hemorrhage.

BACKGROUND: Black-blood MR angiography (BBMRA), which utilizes a non-T1 contrast spin-echo type technique, has been expected to overcome several issues associated with time-of-flight (TOF) MRA. PURPOSE: To investigate the efficacy of BBMRA to detect vasospasms following subarachnoid hemorrhage (SAH). STUDY TYPE: Retrospective. SUBJECTS: Seventeen patients with SAH in their early posttreatment period. FIELD STRENGTH/SEQUENCE: BBMRA, which uses a volumetric isotropic turbo spin-echo acquisition (VISTA), and TOF-MRA on 1.5T scanners. ASSESSMENT: Visualization of supratentorial arteries and veins in BBMRA was rated on a 4-point scale by two neuroradiologists. Another neuroradiologist independently assessed TOF-MRA. The degree of the vasospasm was then evaluated using a 3-point scale by the same readers. The diagnostic performance of the MRAs was evaluated using computed tomography angiography (CTA) or digital subtraction angiography (DSA) as the standard of reference. STATISTICAL TESTS: Wilcoxon signed rank test, McNemar test, and Cohen's kappa coefficient. RESULTS: BBMRA provided superior visualization of the anterior and middle cerebral arteries than TOF-MRA (P < 0.05). The depiction of the veins was more pronounced on BBMRA (P < 0.01). Of the 166 arterial segments evaluated by CTA or DSA, 23 (13.9%) could not be assessed using TOF-MRA because of high signal hemorrhage, whereas BBMRA enabled visualization of all the segments. Vasospasm was confirmed in 30 segments by CTA or DSA. The sensitivity, specificity, and positive and negative predictive values were 73, 96, 76, and 95 for TOF-MRA and 91, 100, 100, and 98 for BBMRA, respectively (P = 0.13 for sensitivity, P = 0.06 for specificity). The agreement of the degree of vasospasm between MRA and the standard of reference, as indicated by kappa value, was 0.71 (95% confidence interval [CI], 0.55-0.87) for TOF-MRA and 0.91 (95% CI, 0.82-0.99) for BBMRA. DATA CONCLUSION: BBMRA, owing to its contrast properties, may be superior to TOF-MRA for the evaluation of intracranial arteries after SAH. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:800-807.

Differentiation of two subtypes of intrahepatic cholangiocarcinoma: imaging approach.

KEY POINTS: • Mass-forming intrahepatic cholangiocarcinoma can be divided into two subgroups, namley, perihilar and peripheral types. • These two significantly differ in clinico-biological behaviors, and in patients' prognosis as well. • This differentiation may be achieved solely by contrast-enhanced MR imaging findings.

MR elastography of the liver at 3.0 T in diagnosing liver fibrosis grades; preliminary clinical experience.

OBJECTIVES: To clarify the usefulness of 3.0-T MR elastography (MRE) in diagnosing the histological grades of liver fibrosis using preliminary clinical data. MATERIALS AND METHODS: Between November 2012 and March 2014, MRE was applied to all patients who underwent liver MR study at a 3.0-T clinical unit. Among them, those who had pathological evaluation of liver tissue within 3 months from MR examinations were retrospectively recruited, and the liver stiffness measured by MRE was correlated with histological results. Institutional review board approved this study, waiving informed consent. RESULTS: There were 70 patients who met the inclusion criteria. Liver stiffness showed significant correlation with the pathological grades of liver fibrosis (rho = 0.89, p < 0.0001, Spearman's rank correlation). Areas under the receiver operating characteristic curve were 0.93, 0.95, 0.99 and 0.95 for fibrosis score greater than or equal to F1, F2, F3 and F4, with cut-off values of 3.13, 3.85, 4.28 and 5.38 kPa, respectively. Multivariate analysis suggested that grades of necroinflammation also affected liver stiffness, but to a significantly lesser degree as compared to fibrosis. CONCLUSIONS: 3.0-T clinical MRE was suggested to be sufficiently useful in assessing the grades of liver fibrosis. KEY POINTS: MR elastography may help clinicians assess patients with chronic liver diseases. Usefulness of 3.0-T MR elastography has rarely been reported. Measured liver stiffness correlated well with the histological grades of liver fibrosis. Measured liver stiffness was also affected by necroinflammation, but to a lesser degree. 3.0-T MRE could be a non-invasive alternative to liver biopsy.

Which system is better to predict prognosis of patients with hepatocellular carcinoma treated by transcatheter arterial chemoembolization as initial therapy? Comparison between CLIP and JIS in a Japanese population.

Background There has been no consensus as to which system, either the Cancer of the Liver Italian Program (CLIP) or the Japan Integrated Staging (JIS) system, is suitable to predict the prognosis of hepatocellular carcinoma (HCC) patients who underwent transcatheter arterial chemoembolization (TACE) as initial therapy. Purpose To retrospectively compare the usefulness of CLIP and JIS in predicting and stratifying the prognosis of HCC patients treated by TACE. Material and Methods Between 1995 and 2005, consecutive 728 patients with untreated HCC who underwent TACE in our institute were selected for this study. The survival rate and its prognostic factors were assessed by multivariate analysis. Patients were stratified according to the two systems, and their survival rates between the scores were compared. Results The mean follow-up period was 1689 days. The 1-year, 3-year, 5-year, and 10-year survival rates were 83.1%, 55.1%, 34.7%, and 12.8%, respectively. Both systems stratified the prognosis of patients well, but was slightly better in CLIP as compared to in JIS. As for multivariate factor analysis, less severe Child-Pugh classification ( P < 0.001), simple tumor morphology ( P < 0.001), absence of portal vein invasion ( P < 0.001), and lower alpha-fetoprotein (AFP) level ( P < 0.001) were suggested to be independent indicators for favorable survival rate. All of these independent factors were included in CLIP, whereas JIS lacked AFP level. Furthermore, the likelihood χ2-test value was higher, and the Akaike information criterion value was lower for CLIP than for JIS. Conclusion CLIP is more suitable than JIS for predicting prognosis of patients with HCC who would undergo TACE in a Japanese population.

Pilot Study of Hepatic Arterial Infusion Chemotherapy with Interferon-beta and 5-fluorouracil: A New Chemotherapy for Patients with Advanced Hepatocellular Carcinoma.

BACKGROUND/AIMS: The present pilot study aimed to evaluate the safety and efficacy of hepatic arterial infusion chemotherapy (HAIC) with interferon-beta (IFN-ß) and 5-fluorouracil (5-FU) in patients with advanced hepatocellular carcinoma (HCC). METHODOLOGY: We studied 10 patients with advanced HCC and who were unresponsive to previous HAIC using low-dose 5-FU and cisplatin. The median age was 67 years. Eight patients had portal vein tumor thrombosis and four patients had extrahepatic metastasis. Using a drug delivery system, patients were treated with HAIC of IFN-ß (600 MIU/body, three times/week) and 5-FU (250 mg/body, five times/week). Chemotherapy was repeated consecutively for 2 weeks every 4 weeks. RESULTS: Six (60%) patients had a decrease in tumor markers alpha-fetoprotein (APP) or des-gamma-carboxy prothrombin (DCP). The median overall survival was 108 days and the 1-year survival rate was 10.0%. Univariate analysis showed two significant prognostic factors related to long-term survival for more than 60 days: a decrease in APP or DCP 4 weeks after treatment (P = 0.035) and no extra hepatic metastasis (P = 0.035). Severe hepatic injury was not observed. CONCLUSIONS: HAIC with IFN-ß and 5-PU exerts modest antitumor effects and poses no particular safety concerns. This may be a new promising strategy for treatment of advanced HCC.

[The timing of the appearance of oral mucositis induced by concurrent chemoradiotherapy with S-1 for head and neck cancer].

Oral mucositis is a frequent adverse event in patients receiving concurrent chemoradiotherapy for head and neck cancer. Although the management of oral mucositis is essential to improve treatment completion rates, no detailed studies on the time of oral mucositis appearance have been reported. We conducted a retrospective study on the timing of the appearance of oral mucositis induced by concurrent chemoradiotherapy with S-1 for head and neck cancer. A total of 11 patients with head and neck cancer who received concurrent chemoradiotherapy with S-1 were examined. All patients developed oral mucositis within 13.8 ± 5.6 days after the initiation of radiotherapy (20.4 ± 8.1 Gy). In addition, the effects of pain-associated symptoms caused by oral mucositis on the patients' nutritional status, including reduction in caloric intake (24.4% ± 31.1%), weight loss (5.2% ± 5.2%), and duration of a regular diet (24.5 ± 17.1 days), were observed and lasted until the completion of radiation therapy. The delineation of the timing of oral mucositis appearance has become a key motivator for the patients to perform oral care proactively to limit severity and serves as a necessary index for monitoring oral health and managing pain and nutrition.

[Multicenter trial for optimization of bolus tracking settings and contrast material injection protocol in arterial dominant phase of dynamic computed tomography for diagnosis of hepatocellular carcinoma].

Alongside current improvements in the performance of computer tomography (CT) systems, there has been an increase in the use of bolus tracking (BT) to acquire arterial dominant phase images for dynamic CT at optimal timing for characterization of liver focal lesions. However, optimal BT settings have not been established. In the present study, methods of contrast enhancement and BT setting values were evaluated using a multicenter post-marketing surveillance study on contrast media used in patients with chronic hepatitis and/or cirrhosis who had undergone liver dynamic CT for diagnosis of hepatocellular carcinoma, conducted by Daiichi Sankyo Co., Ltd. The results suggested the contrast injection method to be clinically useful if the amount of iodine per kilogram of body weight is set at 600 mg/kg and the injection duration at 30 s. To achieve a good arterial dominant scan under conditions where the injection duration is fixed at 30 s or the average injection duration is 34 s using the fixed injection rate method, the scan delay time should ideally to be set to longer than 13 s. If using the BT method, we recommend that the BT settings should be revalidated in reference to our results.

[Construction and usefulness of the dose management system using DICOM radiation dose structured report (Dose SR) in angiography].

The International Commission on Radiological Protection recommends diagnostic reference levels (DRL) in each radiological examination for justification and optimization of patients' dose in medicine. The aim of our study was to propose the dose management system by utilizing dose information in diagnostic X-ray radiation dose structured report (Dose SR) in The Digital Imaging and Communications in Medicine to optimize radiation dose in institutions. Our dose management system is able to organize dose information obtained from various angiography systems and CTs. It is possible to provide this information to operators for justification and optimization of patient dose. Our system would be useful for the estimation of organ dose and could be used for the determination of local DRL (LDRL) for each radiological practice. In addition, the optimization became possible to compare LDRL with national DRL.

Soft Tissue Stabilization of the Hinge Position for Lateral Closing-Wedge Distal Femoral Osteotomy: An Anatomic Study.

Background: Soft tissue plays an important role in stabilizing the hinge point for osteotomy around the knee. However, insufficient data are available on the anatomic features of the soft tissue around the hinge position for lateral closing-wedge distal femoral osteotomy (LCWDFO). Purpose: To (1) anatomically analyze the soft tissue around the hinge position for LCWDFO, (2) histologically analyze the soft tissue based on the anatomic analysis results, and (3) radiologically define the appropriate hinge point to prevent unstable hinge fracture based on the results of the anatomic and histological analyses. Study Design: Descriptive laboratory study. Methods: In 20 cadaveric knees (age, 82.7 ± 7.8 years; range, 60-96 years), the soft tissue of the distal medial side of the femur was anatomically analyzed. The thicknesses of the periosteum and direct insertion of the adductor tendon (AT) were histologically examined and measured using an electron microscope. The thickness of the periosteum was visualized graphically, and the graph of the periosteum and radiograph of the knee were overlaid using image editing software. The appropriate hinge position was determined based on the periosteal thickness and attachment of the AT. Results: The mean thickness of the periosteum of the metaphysis was 352.7 ± 58.6 µm (range, 213.6-503.4 µm). The overlaid graph and radiograph revealed that the thickness of the periosteum changed at the part corresponding to the transition between the diaphyseal and metaphyseal ends of the femur. The mean width of the AT attached to the distal medial femur from the adductor tubercle toward the distal direction was 7.9 ± 1.3 mm (range, 6.3-9.7 mm). Conclusion: Results indicated that the periosteum and AT support the hinge for LCWDFO within the area surrounded by the apex of the adductor tubercle and the upper border of the posterior part of the lateral femoral condyle. Clinical Relevance: When the hinge point is located within the area surrounded by the apex of the adductor tubercle and the upper border of the posterior part of the lateral femoral condyle, these soft tissues work as stabilizers, and there is no risk of cutting into the joint space.

Effectiveness of deep learning-based reconstruction for improvement of image quality and liver tumor detectability in the hepatobiliary phase of gadoxetic acid-enhanced magnetic resonance imaging.

PURPOSE: To evaluate the effectiveness of deep learning-based reconstruction (DLR) in improving image quality and tumor detectability of isovoxel high-resolution breath-hold fat-suppressed T1-weighted imaging (HR-BH-FS-T1WI) in the hepatobiliary phase (HBP) of Gadoxetic acid-enhanced magnetic resonance imaging (Gd-EOB-MRI). MATERIALS AND METHODS: This retrospective evaluated 42 patients with 98 liver tumors who underwent Gd-EOB-MRI between March 2023 and May 2023 using three techniques based on HBP imaging: isovoxel HR-BH-FS-T1WI reconstructed (1) with DLR (BH-DLR +) and (2) without DLR (BH-DLR -) and (3) HR-FS-T1WI scanned with a free-breathing technique using a navigator-echo-triggered technique and DLR (Navi-DLR +). The three techniques were qualitatively and quantitatively compared by the Friedman test and the Bonferroni post-hoc test. Tumor detectability was compared using the McNemar test. RESULTS: BH-DLR + (3.85, average score of two radiologists) showed significantly better qualitative scores for image noise than BH-DLR - (2.84) and Navi-DLR + (3.37) (p < 0.0167), and Navi-DLR + showed significantly better scores than BH-DLR - (p < 0.0167). BH-DLR + (3.77) and BH-DLR - (3.77) showed significantly better qualitative scores for respiratory motion artifact than Navi-DLR + (2.75) (p < 0.0167), but there was no significant difference in scores between BH-DLR + and BH-DLR - (p > 0.0167). BH-DLR + (0.32) and Navi-DLR + (0.33) showed significantly higher lesion-to-nonlesion CR than BH-DLR - (0.29) (p < 0.0167), but there was no significant difference in lesion-to-nonlesion CR between BH-DLR + and Navi-DLR + (p > 0.0167). BH-DLR + (89.8%) showed significantly better tumor detectability than BH-DLR - (76.0%) and Navi-DLR + (77.6%) (p < 0.05). CONCLUSION: The use of DLR for isovoxel HR-BH-FS-T1WI was effective in improving image quality and tumor detectability.

Gallbladder fossa nodularity in the liver as observed in alcoholic liver disease patients: Analysis based on hepatobiliary phase signal intensity on gadoxetate-enhanced MRI and extracellular volume fraction calculated from routine CT data.

The purpose of this study is to further verify the concept utilizing signal intensity on hepatobiliary phase (HBP) of gadoxetate-enhanced MRI and extracellular volume fraction (ECV) calculated from CT data. Between Jan 2013 and September 2018, consecutive ALD patients who had both quadruple phase CT and gadoxetate-enhanced MRI within six months were retrospectively recruited. Those who had any intervention or disease involvement around gallbladder fossa were excluded. All images were reviewed and ECV was measured by two experienced radiologists. GBFN grades, and their HBP signal intensity or ECV relative to the surrounding background liver (BGL) were analyzed. There were 48 patients who met the inclusion criteria. There were GBFN grade 0/1/2/3 in 11/15/18/4 patients, respectively. The signal intensity on HBP relative to BGL were iso/slightly high/high in 30/15/3 patients, respectively, and ECV ratio (ECV of GBFN divided by that of BGL) was 0.88 ± 0.18, indicating there are more functioning hepatocytes and less fibrosis in GBFN than in BGL. The GBFN grades were significantly correlated to relative signal intensity at HBP (Spearman's rank correlation, p < 0.01, rho value 0.53), and ECV ratio (p < 0.01, rho value -0.45). Our results suggest GBFN in ALD would represent liver tissues with preserved liver function with less fibrosis, as compared to BGL, which are considered to support our hypothesis as shown above.

[Evaluation of Refocus Flip Angle for Three-dimensional Proton Density-weighted Turbo Spin-echo Imaging in Cerebrovascular Black Blood MRA and Comparison with Three-dimensional Time-of-flight MRA].

The three-dimensional time-of-flight (3D-TOF), which is currently the most common acquisition technique of intracranial magnetic resonance angiography (MRA), may result in poor branch visualization due to reduced blood flow velocity. Proton density-weighted volume isotropic turbo spin-echo acquisition (PDVISTA) is less susceptible to these factors and has been reported to be useful in assessing cerebral vasospasm after subarachnoid hemorrhage. In this study, we investigated the effect of refocus flip angle (RFA) for PDVISTA on the contrast between blood vessels and background brain tissue using flow velocity phantom and clinical images, assuming the usefulness of PDVISTA in daily clinical practice. The phantom experiments showed that the contrast ratio significantly improved with decreasing RFA; however, considering the signal-to-noise ratio, RFA 80° was determined as optimal for clinical use. Visual assessment was performed on PDVISTA (RFA 80°) and conventional 3D-TOF MRA clinical images, which suggested the superiority of PDVISTA over 3D-TOF in the delineation of peripheral branches of cerebral vessels. The results suggest that PDVISTA is useful not only for subarachnoid hemorrhage patients but also in daily clinical practice.

Partial splenic embolization improved stomal varices in patient with decompensated liver cirrhosis: a case report.

A 63-year-old man with decompensated liver cirrhosis was admitted for treatment of stomal hemorrhage. Eighteen months earlier, he was diagnosed with rectal and sigmoid colon cancer with multiple lymph node metastases, and he underwent colostomy surgery and postoperative chemotherapy. Sixteen months after the surgery, his stoma began to bleed repeatedly, and he required frequent blood transfusions. A contrast-enhanced computed tomography revealed ectopic varices around the stoma. We considered surgical or endoscopic treatment; however, these approaches would have been technically difficult in this patient. The patient was treated with partial splenic embolization to improve thrombocytopenia and portal hypertension. After two-stage partial splenic embolization, the platelet counts increased, and the concentration of the liver fibrosis marker, Mac-2 binding protein, decreased. In addition, blood flow in the stomal varices decreased, with no recurrence of bleeding. This is a case of recurrent hemorrhage from stomal varices that was successfully treated with partial splenic embolization in a patient with liver cirrhosis. There are no guidelines for hemorrhage from ectopic varices. PSE may present potential utility as a treatment for ectopic variceal bleeding, such as stomal varices.

The usefulness of combined analysis using CIScore and VSRAD parameters for differentiating between dementia with Lewy body and Alzheimer's disease.

PURPOSE: The Cingulate Island score (CIScore) is useful index for differentiating between dementia with Lewy body (DLB) and Alzheimer's disease (AD) using regional cerebral blood flow (rCBF) SPECT. The Z score standing for medial temporal lobe (MTL) atrophy and the ratio of Z score between dorsal brain stem (DBS) to MTL are useful indices for differentiating between DLB and AD using MRI with VSRAD. The current study investigated the diagnostic ability by the combined use of rCBF SPECT and MRI in the differentiation between AD and DLB. MATERIALS AND METHODS: In cases with 42 AD and 28 DLB undertaken Tc-99m-ECD SPECT and MRI, we analyzed differential diagnostic ability between AD and DLB among following conditions by single or combined settings. Namely, they were (1) the CIScore as a parameter of rCBF SPECT (DLB â‰¦ 0.25), (2) Z score value of MTL atrophy (DLB â‰¦ 2.05), (3) the ratio of Z score of DBS to medial temporal gray matter as a parameter of brain atrophy using VSRAD (DLB â‰§ 0.38). Also, we analyzed them both including and omitting the elderly (over 75 years old). RESULTS: The accuracy of differential diagnosis in this condition was 74% for (1), 69% for (2), and 67% for (3). The accuracy by combination condition was 84% for (1) and (2), 81% for (1) and (3), and 67% for (2) and (3), respectively. The combination method by CIScore and the Z score of MTL showed the best accuracy. When we confined condition to ages younger than 75 years, the accuracy improved to 94% in the combination method. CONCLUSION: The combined use of CIScore and Z score of MTL was suggested to be useful in the differential diagnosis between DLB and AD particularly in younger than 75 years old.

Warming effect on miriplatin-lipiodol suspension for potential use as a chemotherapeutic agent for transarterial chemoembolization of hepatocellular carcinoma: In vitro study.

AIM: To elucidate whether warming may reduce the viscosity of miriplatin-lipiodol suspension (MPT/LPD) and also the injection pressure through microcatheters, for potential use as a chemotherapeutic agent of transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). METHODS: Viscosity of MPT/LPD prepared at on-label dose was measured in vitro at 25°C, 30°C, 40°C, 50°C and 60°C using capillary tube method. Reproducibility of viscosity change was also tested. Injection pressure through two different commercially available microcatheters was measured using a rheometer. Data sampling was performed at least twice for each measurement. RESULTS: Viscosity of MPT/LPD was significantly reduced as the temperature was elevated (R(2) = 0.9586, P < 0.0001, Pearson's correlation); at 40°C, it was almost half of that at room temperature (25°C). Repeated warming and cooling down of MPT/LPD revealed good reproducibility of viscosity change. Injection pressure through either microcatheter showed significant reduction when MPT/LPD was warmed (P < 0.05, Spearman's rank correlation coefficient). CONCLUSION: The viscosity and injection pressure through microcatheters of MPT/LPD was confirmed to reduce significantly as the temperature is elevated. MPT/LPD warmed to 40°C has half viscosity as that at room temperature and is considered suitable for clinical use. Warming MPT/LPD may have potential to facilitate the procedure of TACE for HCC.

MRI of intracranial vertebral artery dissection: evaluation of intramural haematoma using a black blood, variable-flip-angle 3D turbo spin-echo sequence.

INTRODUCTION: We investigated the efficacy of three-dimensional black blood T1-weighted imaging (3D-BB-T1WI) using a variable refocusing flip angle turbo spin-echo sequence in the diagnosis of intracranial vertebral artery dissection (VAD). METHODS: Sixteen consecutive patients diagnosed with intracranial VAD underwent magnetic resonance imaging that included 3D time-of-flight-MRA, axial spin-echo T1-weighted images (SE-T1WI) and oblique coronal 3D-BB-T1WI sequences. The visualization, morphology and extent of intramural haematomas were assessed and compared among the sequences. Results obtained by digital subtraction angiography (DSA), 3D-angiography and/or 3D-CT angiography (CTA) were used as standards of reference. RESULTS: 3D-BB-T1WI revealed intramural haematomas in all cases, whereas SE-T1WI and magnetic resonance angiography (MRA) failed to reveal a haematoma in one case and three cases, respectively. The mean visualization grading score for the intramural haematoma was the highest for 3D-BB-T1WI, and there was a statistically significant difference among the sequences (p < 0.001). At least a portion of the intramural haematoma was distinguishable from the lumen on 3D-BB-T1WI, whereas the haematomas were entirely indistinguishable from intraluminal signals on MRA in two cases (12.5%) and on SE-T1WI in one case (6.3%). 3D-BB-T1WI revealed the characteristic crescent shape of the intramural haematoma in 14 cases (87.5%), whereas SE-T1WI and MRA revealed a crescent shape in only 7 cases (43.8%) and 8 cases (50%), respectively. In a consensus reading, 3D-BB-T1WI was considered the most consistent sequence in representing the extent and morphology of the lesion in 14 cases (87.5%), compared to DSA and CTA. CONCLUSION: 3D-BB-T1WI is a promising method to evaluate intramural haematoma in patients with suspected intracranial VAD.