Diffusion tensor imaging of peripheral nerve in patients with chronic inflammatory demyelinating polyradiculoneuropathy: a feasibility study.

INTRODUCTION: The purpose of this study was to assess the clinical feasibility of diffusion tensor imaging (DTI) for the evaluation of peripheral nerves in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). METHODS: Using a 3-T magnetic resonance imaging scanner, we obtained DTI scans of the tibial nerves of 10 CIDP patients and 10 sex- and age-matched healthy volunteers. We prepared fractional anisotropy (FA) maps, measured the FA values of tibial nerves, and compared these values in the two study groups. In nine patients, we also performed tibial nerve conduction studies and analyzed the correlation between the FA values and parameters of the nerve conduction study. RESULTS: The tibial nerve FA values in CIDP patients (median 0.401, range 0.312-0.510) were significantly lower than those in healthy volunteers (median 0.530, range 0.469-0.647) (Mann-Whitney test, p < 0.01). They were significantly correlated with the amplitude of action potential (Spearman correlation coefficient, p = 0.04, r = 0.86) but not with nerve conduction velocity (p = 0.79, r = 0.11). CONCLUSION: Our preliminary data suggest that the noninvasive DTI assessment of peripheral nerves may provide useful information in patients with CIDP.

Percutaneous radiofrequency ablation as first-line treatment for small hepatocellular carcinoma: results and prognostic factors on long-term follow up.

BACKGROUND AND AIMS: We evaluated the prognosis and associated factors in patients with small hepatocellular carcinoma (HCC; up to 3 nodules, each up to 3 cm in diameter) treated with percutaneous radiofrequency ablation (RFA) as first-line treatment. METHODS: Eighty-eight consecutive patients who underwent percutaneous RFA as first-line treatment were enrolled, among whom 70 who had hypervascular HCC nodules which were treated by a combination of transcatheter arterial chemoembolization and RFA. RFA was repeated until an ablative margin was obtained. RESULTS: The rate of local tumor progression at 1 and 3 years was 4.8% and 4.8%, respectively. The rate of overall survival at 3 and 5 years was 83.0% and 70.0%, and the rate of disease-free survival at 3 and 5 years was 34.0% and 24.0%, respectively. On multivariate analysis, age (< 70 years; hazard ratio [HR] = 2.341, 95% confidence interval [CI] = 1.101-4.977, P = 0.027) and indocyanine green retention rate at 15 min (< 15%; HR = 3.621, 95% CI = 1.086-12.079, P = 0.036) were statistically significant determinants of overall survival, while tumor number (solitary, HR = 2.465, 95% CI = 1.170-5.191, P = 0.018) was identified for disease-free survival. Overall survival of patients with early recurrence after RFA was significantly worse than that of patients with late recurrence. Tumor size was the only independent risk factor of early recurrence after RFA of HCC (tumor size > 2 cm; risk ratio [RR] = 4.629, 95% CI = 1.241-17.241, P = 0.023). CONCLUSION: Percutaneous RFA under the protocol reported here has the potential to provide local tumor control for small HCC. In addition to host factors, time interval from RFA to recurrence was an important determinant of prognosis.

Risk factors for severity of pneumothorax after CT-guided percutaneous lung biopsy using the single-needle method.

The purpose of this study is to evaluate the risk factors for the severity of pneumothorax after computed tomography (CT)-guided percutaneous lung biopsy using the single-needle method. We reviewed 91 biopsy procedures for 90 intrapulmonary lesions in 89 patients. Patient factors were age, sex, history of ipsilateral lung surgery and grade of emphysema. Lesion factors were size, location and pleural contact. Procedure factors were position, needle type, needle size, number of pleural punctures, pleural angle, length of needle passes in the aerated lung and number of harvesting samples. The severity of pneumothorax after biopsy was classified into 4 groups: "none", "mild", "moderate" and "severe". The risk factors for the severity of pneumothorax were determined by multivariate analyzing of the factors derived from univariate analysis. Pneumothorax occurred in 39 (43%) of the 91 procedures. Mild, moderate, and severe pneumothorax occurred in 24 (26%), 8 (9%) and 7 (8%) of all procedures, respectively. Multivariate analysis showed that location, pleural contact, number of pleural punctures and number of harvesting samples were significantly associated with the severity of pneumothorax (p < 0.05). In conclusion, lower locations and non-pleural contact lesions, increased number of pleural punctures and increased number of harvesting samples presented a higher severity of pneumothorax.

Significant correlation between spleen volume and thrombocytopenia in liver transplant patients: a concept for predicting persistent thrombocytopenia.

Interferon (IFN) therapy with or without ribavirin treatment is well established as a standard antiviral treatment for hepatitis C virus (HCV)-infected patients. However, susceptibility to thrombocytopenia is a major obstacle for initiating or continuing this therapy, particularly in liver transplant (LTx) recipients with HCV. Studies have reported that splenectomy performed concurrently with LTx is a feasible strategy for conditioning patients for anti-HCV IFN therapy. However, the relationship between the severity of splenomegaly and alterations in the blood cytopenia in LTx recipients remains to be clarified. Here, we analyzed the relationship between spleen volume (SV) and thrombocytopenia in 45 patients who underwent LTx at Hiroshima University Hospital. The extent of pre-LTx splenomegaly [the SV to body surface area (BSA) ratio in an individual] was inversely correlated with both the post-LTx white blood cell count and platelet (PLT) count (P < 0.001). Furthermore, the PLT count of patients with thrombocytopenia (PLT count or= 400), persistent thrombocytopenia is predictable after LTx.

Prospective ECG-triggered axial CT at 140-kV tube voltage improves coronary in-stent restenosis visibility at a lower radiation dose compared with conventional retrospective ECG-gated helical CT.

The purpose of this study was to compare coronary 64-slice CT angiography (CTA) protocols, specifically prospective electrocardiograph (ECG)-triggered and retrospective ECG-gated CT acquisition performed using a tube voltage of 140 kV and 120 kV, regarding intracoronary stent imaging. Coronary artery stents (n = 12) with artificial in-stent restenosis (50% luminal reduction, 40 HU) on a cardiac phantom were examined by CT at heart rates of 50-75 beats per minute (bpm). The subjective visibility of in-stent restenosis was evaluated with a three-point scale (1 clearly visible, 2 visible, and 3 not visible), and artificial lumen narrowing [(inner stent diameter - measured lumen diameter)/inner stent diameter], lumen attenuation increase ratio [(in-stent attenuation - coronary lumen attenuation)/coronary lumen attenuation], and signal-to-noise ratio of in-stent lumen were determined. The effective dose was estimated. The artificial lumen narrowing (mean 43%), the increase of lumen attenuation (mean 46%), and signal-to-noise ratio (mean 7.8) were not different between CT acquisitions (p = 0.12-0.91). However, the visibility scores of in-stent restenosis were different (p < 0.05) between ECG-gated CTA techniques: (a) 140-kV prospective (effective dose 4.6 mSv), 1.6; (b) 120-kV prospective (3.3 mSv), 1.8; (c) 140-kV retrospective (16.4-18.8 mSv), 1.9; and (d) 120-kV retrospective (11.0-13.4 mSv), 1.9. Thus, 140-kV prospective ECG-triggered CTA improves coronary in-stent restenosis visibility at a lower radiation dose compared with retrospective ECG-gated CTA.

Intra-arterial 5-fluorouracil/interferon combination therapy for advanced hepatocellular carcinoma with or without three-dimensional conformal radiotherapy for portal vein tumor thrombosis.

BACKGROUND: The aim of this study was to elucidate the efficacy of intra-arterial 5-fluorouracil (5-FU) and interferon (IFN) alpha combined with three-dimensional conformal radiotherapy (3D-CRT) for portal vein tumor thrombosis (PVTT). METHODS: The study groups were 16 HCC patients with PVTT treated with 5-FU/IFN combined with 3D-CRT (RT group) and 16 matched controls treated with 5-FU/IFN alone (non-RT group). We compared the survival rate, response, time to progression (TTP), portal hypertension-related events (PREs) and safety. RESULT: Complete response (CR) of PVTT, partial response (PR), stable disease (SD) and progressive disease (PR) were noted in three (19%), nine (56%), four (25%) and zero patients of the RT group, one (6%), three (19%), seven (44%) and five (31%) patients of the non-RT group, respectively. The objective response rate of PVTT was higher in the RT group (P = 0.012). The rate of PREs (variceal rupture, worsening of esophagogastric varices and emerging of uncontrollable ascites) was lower in the RT group than in the non-RT group (P = 0.0195). The median survival time of the RT group (7.5 months) was not significantly different from that of the non-RT group (7.9 months). RT-induced liver disease was not observed. CONCLUSION: 5-FU/IFN combination with 3D-CRT for PVTT improved the response rate of PVTT and reduced the incidence of portal hypertension-related events.

Distribution of platinum in the female genital tract and efficacy of radiotherapy combined with transcatheter arterial infusion of cisplatin for locally advanced stage IIIb carcinoma of the uterine cervix.

The current main treatment for locally advanced stage III/IV cervical cancer involves chemoradiotherapy. In this study, we investigated the distribution of platinum in the female genital tract by intra-arterial infusion of platinum (carboplatin 150 mg) during surgery and examined the therapeutic effects of radiotherapy with transcatheter arterial infusion (TAI) of cisplatin for locally advanced carcinoma of the uterine cervix. From January 1991, we randomly selected 26 patients with locally advanced stage IIIb cervical cancer to receive radiotherapy combined with TAI of 120 mg/body cisplatin twice a month at an interval of 4 weeks. Radiotherapy routinely involved 50 Gy of external beam irradiation to the whole pelvis and 12-24 Gy (point A dose) of intracavitary irradiation using a remote afterloading system. The mean platinum concentration in the cervical cancer was 1.77 microg/g wet tissue (wt) and high value, but the genital tract also contained the same platinum concentration. The platinum concentration in each regional lymph node was 1.10-1.48 microg/g wt, and its level of platinum was equal to that in the female genital tract. The effective histologic response rate was 88.5% (23/26). The median follow-up period was 38 months. The cumulative survival rate was 74.0%. Serious acute adverse reactions interfering with treatment were not observed. Based on these results, intra-arterial infusion of platinum produced a therapeutic effect on the primary cervical cancer site and the other parts of the female genital tract. We concluded that radiotherapy with TAI of cisplatin achieved superior therapeutic efficacy in locally advanced stage IIIb cervical cancer.

Evaluation of patients with esophageal varices after endoscopic injection sclerotherapy using multiplanar reconstruction MDCT images.

OBJECTIVE: The purpose of our study was to assess the relationship between hemodynamic changes in portosystemic collaterals and the prognosis of patients with esophageal varices after endoscopic injection sclerotherapy using multiplanar reconstruction (MPR) MDCT images. SUBJECTS AND METHODS: The subjects of this prospective study were 53 patients who underwent endoscopic injection sclerotherapy for esophageal varices. We evaluated the reconstructed MPR images of portosystemic collaterals before and after endoscopic injection sclerotherapy. Patients were divided into three groups based on the rate of change in the diameter of the feeding vessel into complete eradication (group A), narrowing (group B), and no change (group C). We analyzed the relationship between hemodynamic change in portosystemic collaterals and prognosis. RESULTS: The left gastric vein, posterior gastric vein, and left gastric vein plus posterior gastric vein were the main feeding vessels (n=44 [83%] of patients, n=5 [9%], and n=4 [8%], respectively). The proportions of patients of groups A, B, and C were 19% (n=10), 24% (n=13), and 57% (n=30), respectively. The relapse-free rates at 2 years after endoscopic injection sclerotherapy were 100%, 65%, and 52% in groups A, B, and C, respectively (p<0.05). For group C, the relapse-free rate at 2 years after endoscopic injection sclerotherapy of patients with a large-diameter paraesophageal vein (>or= 3 mm, 63%) was significantly higher than in those with a small-diameter paraesophageal vein (<3 mm, 36%; p<0.05). However, there were no significant differences in the survival rate among the three groups. CONCLUSION: MPR MDCT images on portosystemic collaterals can accurately predict relapse of esophageal varices after endoscopic injection sclerotherapy.

Survey of aorta and coronary arteries with prospective ECG-triggered 100-kV 64-MDCT angiography.

OBJECTIVE: The purpose of this study was to investigate the feasibility of prospective ECG-triggered axial 64-MDCT angiography of the aorta and coronary arteries performed at a tube voltage of 100 kV. SUBJECTS AND METHODS: Thirty patients with a heart rate less than 75 beats/min who were referred for aortic CT angiography were enrolled. The image quality of the ascending aorta, aortic valve, and coronary arteries was evaluated for motion artifacts. Contrast enhancement (mean attenuation) was measured in the ascending aorta, descending aorta, and bifurcation of the aorta. Aortic valve and coronary artery lesions were surveyed. RESULTS: Acceptable image quality was achieved in 100% (30/30) of cases for the ascending aorta, 97% (29/30) of cases for the aortic valve, and 98% (442/452) of coronary arterial segments. Contrast enhancement was greater than 200 HU and was satisfactory (ascending aorta, 379 +/- 80 HU; descending aorta, 354 +/- 72 HU; bifurcation, 355 +/- 96 HU). Lesions found in the aortic valve were plaque (n = 16) and bicuspid valve (n = 1) and in the coronary arteries were > or = 50% luminal stenosis (n = 5), plaque (n = 21), myocardial bridge (n = 12), and anomalous origin (n = 1). The effective radiation dose was estimated to be 7.5 +/- 1.7 mSv. CONCLUSION: For patients with a heart rate less than 75 beats/min, prospective ECG-triggered axial CT angiography at a tube voltage of 100 kV has the potential to provide clinically relevant information about the aorta and coronary arteries with low radiation exposure.

FDG positron emission tomography/computed tomography for the detection of extrahepatic metastases from hepatocellular carcinoma.

AIMS: To compare the efficacy of positron emission tomography (PET) computed tomography (CT), multi-detector helical computed tomography (MDCT) and bone scintigraphy for the detection of extrahepatic metastases in patients with hepatocellular carcinoma (HCC). METHODS: Thirty-four patients diagnosed with metastatic HCC were enrolled in this study. The lesions included lung (n = 18), bone (n = 12) and lymph node (n = 16) metastases. For receiver operating characteristic (ROC) analysis, lesions were diagnosed as metastatic HCC by two experienced abdominal radiologists. Another three physicians independently reviewed both positive and negative images. Each physician read three sets of images of MDCT, PET-CT and bone scintigraphy for bone metastasis. RESULTS: The mean sensitivity and specificity for diagnosis of lung metastasis were 85.2 and 88.9% for MDCT, and 59.2 and 92.6% for PET-CT, respectively. For lymph node metastasis, these values were 62.5 and 79.2% for MDCT, and 66.7 and 91.7% for PET-CT, respectively; and for bone metastasis 41.6 and 94.5% for MDCT, 83.3 and 86.1% for PET-CT, and 52.7 and 83.3% for bone scintigraphy, respectively. The mean Az values were 0.95 and 0.77 for MDCT and PET-CT in lung metastasis, respectively, 0.75 and 0.80 for MDCT and PET-CT for lymph node metastasis, respectively, and 0.59, 0.88 and 0.62 for MDCT, PET-CT and bone scintigraphy for bone metastasis, respectively. CONCLUSION: PET-CT has high sensitivity and is more suitable for the detection of bone metastases from primary HCC, relative to MDCT and bone scintigraphy.

Results of a preliminary study using hypofractionated involved-field radiation therapy and concurrent carboplatin/paclitaxel in the treatment of locally advanced non-small-cell lung cancer.

BACKGROUND: We aimed to evaluate the feasibility and efficacy of hypofractionated involved-field radiation therapy (IFRT) omitting elective nodal irradiation (ENI) with concurrent chemotherapy for locally advanced non-small-cell lung cancer (NSCLC). METHODS: Between July 2004 and July 2006, ten patients with locally advanced NSCLC were included in this study. One had stage IIIA and 9 had stage IIIB disease. The treatment consisted of IFRT in fractions of 2.5 Gy and weekly carboplatin (CBDCA)/paclitaxel (PTX). Hypofractionated IFRT with a median total dose of 65 Gy with median percent total lung volume exceeding 20 Gy (V20) of 20.2%, and a median of five courses of chemotherapy with weekly CBDCA (area under the curve, 1.5-2.0)/PTX (30-35 mg/m(2)) were given to all patients. RESULTS: The median survival time and the 1-, 2-, and 3-year overall survival rates were 29.5 months and 90.0%, 58.3%, and 43.8%, respectively. No elective nodal failure was encountered during the median follow up of 18.2 months. No acute or late toxicities of grade 3 or worse were observed. No in-field recurrence occurred in the group with a total dose of 67.5 Gy or more, but there was such recurrence in 83.3% of those in the group with less than 67.5 Gy. CONCLUSION: Hypofractionated IFRT with weekly CBDCA/PTX was a feasible treatment regimen. Hypofractionated IFRT with a total dose of 67.5 Gy or more could be a promising modality to improve the treatment results in patients with locally advanced NSCLC.

Decrease of renal function due to warm ischemia after laparoscopic partial nephrectomy: evaluation using 99mTc-DMSA renal scintigraphy.

INTRODUCTION: The purpose of this study is, using technetium-99m-dimercaptosuccinic acid ((99m)Tc-DMSA), to evaluate the decrease of renal function caused by warm ischemia. PATIENTS AND METHODS: The (99m)Tc-DMSA scan was performed before and 1, 3 and 6 months after the operation for 19 consecutive patients. The patients were divided into three groups by warm ischemic time (group A: 40 min intersection 60 min). Renal function of the unresected part was defined as the uptake to unresected part relative to the uptake to the contralateral kidney. The reduction of renal function was expressed as a ratio of the function after the surgery divided by function before the surgery and was compared between the three groups. RESULTS: The reduction in group C after 1 and 3 months tended to be greater than that in group A or B, although not reaching statistical significance (one-way ANOVA test, 1 month: p = 0.15 and 3 months: p = 0.13). There was a significant difference in reduction of renal function between the three groups after 6 months (one-way ANOVA test, p = 0.02). The Scheffé test showed a statistical significance between groups A and C (p < 0.05). CONCLUSION: Renal function calculated by (99m)Tc-DMSA shows that prolonged ischemic time causes significant damage to the kidney.

Differential diagnosis of hepatic tumor-like lesions in dog by using dynamic CT scanning.

Dynamic liver CT scanning is used to observe the hemodynamics of hepatic tumor-like lesions by taking images sequentially after administration of contrast media. In this study in dogs, we compared the hemodynamic patterns of hepatocellular carcinoma (HCC), one of the malignant tumors, and nodular hyperplasia (NH), a benign tumor that is more common in older dogs. Thirty-six dogs with HCC and 40 dogs with NH, which were histopathologically diagnosed at Taniura Animal Hospital, were used as subjects. Dynamic CT scanning was performed and the data of each scanning phase were collected. Dilated blood vessels, septum formation, and capsule formation were noted in the tumors from 25, 17, and 25 animals with HCC, respectively. In the arterial phase, high density and low contrast were noted in 8 and 23 dogs, respectively. Low density was noted in 34 dogs in the equilibrium phase. In contrast, no dilated blood vessels, septum formation, or capsule formation was noted in the dogs with NH. High density, low contrast, and low density were noted in 8, 9, and 23 dogs, respectively, in the arterial phase. In the equilibrium phase, the enhancement level was equal to the surrounding liver tissues in all animals. The CT values of HCC in the plain, the arterial phase, portal venous phase and equilibrium phase after the administration of contrast media, were significantly (p < 0.05 to 0.001) lower than those of the surrounding liver tissues. In the arterial phase, the percent incidence of low density was significantly less in HCC than NH, while that of low contrast was significantly greater (p < 0.001) in HCC than NH. Dynamic CT scanning identified differences between the hemodynamics and internal structures of HCC and NH in dogs. Dynamic liver CT scanning can therefore be considered a useful technique in the differential diagnosis of hepatic tumor-like lesions in dogs.

[Concurrent chemoradiation experience of the local relapse of rectal cancer patients].

We have reported the concurrent chemoradiation experience of local relapse of rectal cancer patients. From October 2004 to January 2007 we have treated consecutive 10 patients with radiation and the concurrent chemotherapy by CPT-11+S-1. Of 10 lesions, 5(50%)had a complete response, 2(20%)a partial response, 3(30%)a stable disease, yielding an overall response rate of 70%. Three year survival and relapse free survival was 64% and 22 months, respectively. Four patients live without cancers, 3 patients died with cancers and 2 patients live with cancers. Three patients had acute complication(more than Grade 2)including 3 appetite losses. The concurrent chemoradiation is feasible for out-patients and seems to offer good results for the local relapse of rectal cancer patients.

Anterior chamber configuration in patients with glaucoma: MR gonioscopy evaluation with half-Fourier single-shot RARE sequence and microscopy coil.

The purpose of the study was to determine the accuracy of half-Fourier single-shot rapid acquisition with relaxation enhancement high-spatial-resolution magnetic resonance (MR) imaging performed with a microscopy coil in the diagnosis of narrow anterior chamber angle in patients with glaucoma. Slit-lamp biomicroscopy served as the reference standard. The institutional review board approved this study, and written informed consent was obtained from the 20 recruited patients. There was excellent agreement between MR gonioscopy and slit-lamp biomicroscopy in the classification of anterior chamber angles as narrow or open (kappa = 0.89 [95% confidence interval: 0.69, 1.10]). MR gonioscopy has substantial potential as a technique used to evaluate glaucoma.

Prospective versus retrospective ECG-gated 64-detector coronary CT angiography: assessment of image quality, stenosis, and radiation dose.

PURPOSE: To show that prospective electrocardiographically (ECG)-triggered coronary computed tomographic (CT) angiography (hereafter, prospective CT angiography) is at least as effective as retrospective ECG-gated coronary CT angiography (hereafter, retrospective CT angiography). MATERIALS AND METHODS: Institutional review committee approval and informed consent were obtained. Sixty patients with heart rates of less than 75 beats per minute who were referred for coronary CT angiography were enrolled. Both prospective and retrospective CT angiography were performed with a 64-detector scanner. Data acquisition times were recorded. Two independent cardiac radiologists evaluated subjective image quality (1, excellent; 4, poor) and severity of stenosis (0% occlusion, 1%-49% occlusion, 50%-75% occlusion, and >75% occlusion) with the 17-segment American Heart Association classification model. Discrepancies were settled by consensus. Effective radiation doses of prospective and retrospective CT angiography were calculated with volume CT dose index. Data regarding acquisition time and radiation exposure for prospective and retrospective CT angiography were compared. The Student t test was performed, and kappa statistics were calculated. RESULTS: Mean data acquisition time of prospective CT angiography was shorter than that of retrospective CT angiography (5.6 seconds +/- 1.1 [standard deviation] vs 6.7 seconds +/- 1.1, respectively; P < .01). Consensus-determined image quality in coronary artery branches was similar between prospective CT angiography and retrospective CT angiography (1.15 vs 1.13, respectively; P = .992). Excellent agreement between prospective CT angiography and retrospective CT angiography was observed in the detection of significant (>or=50% occlusion) coronary artery stenoses per segment (kappa = 0.882) and in the grading of stenoses per patient (kappa = 0.829). Calculated effective dose with prospective CT angiography was 79% lower than that with retrospective CT angiography (4.1 mSv +/- 1.8 vs 20.0 mSv +/- 3.5, respectively; P < .001). CONCLUSION: Prospective CT angiography can reduce radiation dose below that of retrospective CT angiography with dose modulation, while maintaining image quality and the ability to assess luminal obstructions in patients with heart rates of less than 75 beats per minute.

Beneficial effects of living-donor liver transplantation on esophageal varices.

BACKGROUND: Liver transplantation (LT) is known to improve bleeding esophageal varices (EVs) and portal hypertension. However, many issues related to EVs after LT remain unresolved, such as whether LT reduces blood supply to EVs, improves the diameter of unruptured EVs, or improves or worsens EVs. The aim of this retrospective study was to determine the effects of living-donor liver transplantation (LDLT) in patients with hepatic failure on EVs and inflow vessels to EVs and the factors associated with deterioration of EVs after LDLT. METHODS: The study subjects were 35 patients with cirrhosis who underwent LDLT. Endoscopy and multidetector helical computed tomography (MDCT) were performed before and after LDLT. The diameter of the inflow vessel of EVs was measured by MDCT before and after LDLT, together with the LDLT-related reduction rate of the diameter of the gastric vein (RRGV). RESULTS: Endoscopic examination showed improvement of EVs in 30 of 35 (86%) patients. RRGV improved in 17/35 (49%) patients, did not change in 13/35 (37%), and deteriorated in 5/35 (14%). The cause of RRGV deterioration seemed to be either the complication of portal vein or graft failure. In patients examined endoscopically at >1 year after LDLT, improvement of EVs was associated with significant changes in the rate of reduction of the major inflow vessel diameter and Child-Pugh score, compared with those who showed no improvement. CONCLUSIONS: LDLT results in improvement of EVs. EVs improved in 86% of the patients. Measurement of RRGV with MDCT is a good tool for prediction of EV improvement after LDLT.

Accuracy of sonographic elastography in the differential diagnosis of enlarged cervical lymph nodes: comparison with conventional B-mode sonography.

OBJECTIVE: The purpose of our study was to evaluate the diagnostic performance of sonographic elastography and B-mode sonography individually and combined in the differentiation of reactively and metastatically enlarged cervical lymph nodes. SUBJECTS AND METHODS: Eighty-five lymph nodes (metastatic, n = 53; reactive, n = 32) from 37 patients were examined by both elastography and B-mode sonography in this prospective study. Elastographic patterns were determined on the distribution and percentage of the lymph node area with high elasticity (hard), with pattern 1 being an absent or very small hard area to pattern 5, a hard area occupying the entire lymph node. The cutoff line for reactive versus metastatic was set between patterns 2 and 3; patterns 3-5 were considered metastatic. B-mode sonographic diagnosis was based on the sum of scores for five criteria: short-axis diameter, shape, border (regular or irregular), echogenicity (homogeneous or inhomogeneous), and hilum (present or absent). The cutoff line for reactive versus metastatic was set between scores 6 and 7; scores 5 and 6 were considered reactive, and scores 7-10, metastatic. RESULTS: Sensitivity, specificity, and accuracy of B-mode sonography were 98%, 59%, and 84%, respectively; 83%, 100%, and 89% for elastography; and 92%, 94%, and 93% for the combined evaluation. CONCLUSION: The combination of highly specific elastography with highly sensitive conventional B-mode sonography has the potential to further improve the diagnosis of metastatic enlarged cervical lymph nodes.

Radiation dose, image quality, stenosis measurement, and CT densitometry using ECG-triggered coronary 64-MDCT angiography: a phantom study.

OBJECTIVE: The purpose of this study was to compare prospective ECG-triggered and retrospective ECG-gated coronary 64-MDCT angiography as to radiation dose, image quality, accuracy of stenosis measurement, and CT densitometry. MATERIALS AND METHODS: Coronary artery models (n = 3) with different plaque densities (approximately 50, approximately 110, and approximately 1,000 H) on a cardiac phantom were scanned in variable heart rate sequences (n = 14) with both prospective ECG-triggered and retrospective ECG-gated scanning. Radiation dose, image quality graded by motion and stairstep artifacts (grade 1, excellent, to grade 4, poor, with grades 1 and 2 defined as satisfactory), accuracy of stenosis measurement (area; 18%, 50%, and 82%), and CT densitometry of plaques (soft, approximately 50; and intermediate, approximately 110 H) were compared between the two protocols using the Mann-Whitney U test and repeated measures. RESULTS: The radiation dose of prospective ECG-triggered CT angiography (CTA) (3.0 mSv) was lower than that of retrospective ECG-gated CTA (11.7-13.0 mSv) when the same tube current (mA) and voltage (kVp) were used in both methods. Prospective ECG-triggered CTA images were assigned a satisfactory quality rating in stable heart rate up to 75 beats per minute (bpm) when using the minimal X-ray exposure time. In this range, there were no significant differences in stenosis measurement (p = 0.17) and CT densitometry (p = 0.93) between the two protocols. CONCLUSION: Prospective ECG-triggered coronary 64-MDCT has the potential to reduce radiation exposure while maintaining the diagnostic performance of retrospective ECG-gated coronary 64-MDCT.

Optimal cardiac phase for coronary artery calcium scoring on single-source 64-MDCT scanner: least interscan variability and least motion artifacts.

OBJECTIVE: The purpose of our study was to investigate the cardiac phase with the least interscan variability and motion artifacts on coronary artery calcium studies using a 64-MDCT scanner. SUBJECTS AND METHODS: Ninety-one patients with suspected coronary artery disease were scanned twice on retrospective ECG-gated helical scans. Images with 2.5-mm thickness and 1.25-mm interval at nine cardiac phases (center of cardiac phase: 40-80% in 5% increments) were reconstructed. The interscan variability of coronary artery scores (Agatston, volume, and mass) per patient and motion artifact scores per branch, subjectively assigned by motion artifact grading (1, none; 2, minor; and 3, major), were compared between cardiac phases for all patients, low (< 65 beats per minute [bpm]) and high (>or= 65 bpm) heart rate patient groups. RESULTS: For all patients, two-factor factorial analysis of variance revealed that the interscan variability was different between cardiac cycles (p < 0.01); however, this was not statistically significant between scoring algorithms (p = 0.46). The least variability was obtained at 70% on Agatston (8%) and volume (7%) and at 75% on mass (7%). Adjacent categories logit model analysis revealed that the motion artifact score was the least at 75% (left anterior descending coronary artery, 1.3; left circumflex coronary artery, 1.4; and right coronary artery, 1.9 in all patients) and that a smaller difference in calcium scores between the scans led to a smaller motion artifact score (p < 0.05). CONCLUSION: Middiastole reconstruction (center of cardiac phase: 70-75%), with the least interscan variability and the least motion artifacts, is recommended on 64-MDCT.