Fumi Kato

Rapid estimation of split renal function in kidney donors using software developed for computed tomographic renal volumetry

PURPOSE To evaluate the speed and precision of split renal volume (SRV) measurement, which is the ratio of unilateral renal volume to bilateral renal volume, using a newly developed software for computed tomographic (CT) volumetry and to investigate the usefulness of SRV for the estimation of split renal function (SRF) in kidney donors. METHOD Both dynamic CT and renal scintigraphy in 28 adult potential living renal donors were the subjects of this study. We calculated SRV using the newly developed volumetric software built into a PACS viewer (n-SRV), and compared it with SRV calculated using a conventional workstation, ZIOSOFT (z-SRV). The correlation with split renal function (SRF) using (99m)Tc-DMSA scintigraphy was also investigated. RESULTS The time required for volumetry of bilateral kidneys with the newly developed software (16.7±3.9s) was significantly shorter than that of the workstation (102.6±38.9s, p<0.0001). The results of n-SRV (49.7±4.0%) were highly consistent with those of z-SRV (49.9±3.6%), with a mean discrepancy of 0.12±0.84%. The SRF also agreed well with the n-SRV, with a mean discrepancy of 0.25±1.65%. The dominant side determined by SRF and n-SRV showed agreement in 26 of 28 cases (92.9%). CONCLUSION The newly developed software for CT volumetry was more rapid than the conventional workstation volumetry and just as accurate, and was suggested to be useful for the estimation of SRF and thus the dominant side in kidney donors.

Splenic volume measurements on computed tomography utilizing automatically contouring software and its relationship with age, gender, and anthropometric parameters.

OBJECTIVE The present research was conducted to establish the normal splenic volume in adults using a novel and fast technique. The relationship between splenic volume and age, gender, and anthropometric parameters was also examined. MATERIALS AND METHODS The splenic volume was measured in 230 consecutive patients who underwent computed tomography (CT) scans for various indications. Patients with conditions that have known effect on the spleen size were not included in this study. A new technique using volumetric software to automatically contour the spleen in each CT slice and quickly calculate splenic volume was employed. Inter- and intra-observer variability were also examined. RESULTS The average splenic volume of all the subjects was 127.4+/-62.9 cm(3), ranging from 22 to 417 cm(3). The splenic volume (S) correlated with age (A) (r=-0.33, p<0.0001), body weight (W) (r=0.35, p<0.0001), body mass index (r=0.24, p<0.0001) and body surface area (BSA) (r=0.31, p<0.0001). The age-adjusted splenic volume index correlated with gender (p=0.0089). The formulae S=W[6.47A(-0.31)] and S=BSA[278A(-0.36)] were derived and can be used to estimate the splenic volume. Inter- and intra-observer variability were 6.4+/-9.8% and 2.8+/-3.5% respectively. CONCLUSION Of the anthropometric parameters, the splenic volume was most closely linked to body weight. The automatically contouring software as well as formulae can be used to obtain the volume of the spleen in regular practice.

Renal cortical volume measured using automatic contouring software for computed tomography and its relationship with BMI, age and renal function

PURPOSE To evaluate the relationship between renal cortical volume, measured by an automatic contouring software, with body mass index (BMI), age and renal function. MATERIALS AND METHODS The study was performed in accordance to the institutional guidelines at our hospital. Sixty-four patients (34 men, 30 women), aged 19 to 79 years had their CT scans for diagnosis or follow-up of hepatocellular carcinoma retrospectively examined by a computer workstation using a software that automatically contours the renal cortex and the renal parenchyma. Body mass index and estimated glomerular filtration rate (eGFR) were calculated based on data collected. Statistical analysis was done using the Student t-test, multiple regression analysis, and intraclass correlation coefficient (ICC). RESULTS The ICC for total renal and renal cortical volumes were 0.98 and 0.99, respectively. Renal volume measurements yielded a mean cortical volume of 105.8cm(3)±28.4SD, mean total volume of 153cm(3)±39SD and mean medullary volume of 47.8cm(3)±19.5SD. The correlation between body weight/height/BMI and both total renal and cortical volumes presented r=0.6, 0.6 and 0.4, respectively, p<0.05, while the correlation between renal cortex and age was r=-0.3, p<0.05. eGFR showed correlation with renal cortical volume r=0.6, p<0.05. CONCLUSION This study demonstrated that renal cortical volume had a moderate positive relationship with BMI, moderate negative relationship with age, and a strong positive relationship with the renal function, and provided a new method to routinely produce volumetric assessment of the kidney.

Transcatheter Arterial Embolization with Absolute Ethanol Injection for Enlarged Polycystic Kidneys after Failed Metallic Coil Embolization

Kidney enlargement in autosomal-dominant polycystic kidney disease (ADPKD) may cause symptoms by compressing the alimentary tract, lungs, and heart. The clinical symptoms may be progressive, may markedly decrease quality of life, and may even be life-threatening. Although treatment of this disease is often difficult, transcatheter arterial embolization (TAE) with metallic coils has been reported as a renal contraction therapy that is less invasive than surgery. The present report describes a case of ADPKD successfully treated by TAE with absolute ethanol after a previous TAE procedure with metallic coils failed to contract the affected kidneys because of recanalization.

Single-slice epicardial fat area measurement: do we need to measure the total epicardial fat volume?

PurposeThe aim of this study was to assess a method for measuring epicardial fat volume (EFV) by means of a single-slice area measurement. We investigated the relation between a single-slice fat area measurement and total EFV.Methods and methodsA series of 72 consecutive patients (ages 65 ± 11 years; 36 men) who had undergone cardiac computed tomography (CT) on a 64-slice multidetector scanner with prospective electrocardiographic triggering were retrospectively reviewed. Pixels in the pericardium with a density range from −230 to −30 Hounsfield units were considered fat, giving the per-slice epicardial fat area (EFA). The EFV was estimated by the summation of EFAs multiplied by the slice thickness. We investigated the relation between total EFV and each EFA.ResultsEFAs measured at several anatomical landmarks—right pulmonary artery, origins of the left main coronary artery, right coronary artery, coronary sinus—all correlated with the EFV (r = 0.77–0.92). The EFA at the LMCA level was highly reproducible and showed an excellent correlation with the EFV (r = 0.92).ConclusionThe EFA is significantly correlated with the EFV. The EFA is a simple, quick method for representing the time-consuming EFV, which has been used as a predictive indicator of cardiovascular diseases.

Identifying relations between imaging phenotypes and molecular subtypes of breast cancer: Model discovery and external validation

To determine whether dynamic contrast enhancement magnetic resonance imaging (DCE‐MRI) characteristics of the breast tumor and background parenchyma can distinguish molecular subtypes (ie, luminal A/B or basal) of breast cancer.

The strain-encoded (SENC) MR imaging for detection of global right ventricular dysfunction in pulmonary hypertension

The aim of this study was to explore whether the regional peak longitudinal (LS) and circumferential strains (CS) at the right ventricular (RV) free wall could be used to identify global RV dysfunction in relation to RV ejection fraction (RVEF) and plasma concentration of brain natriuretic peptide (BNP) in pulmonary hypertension (PH). A total of 37 consecutive patients diagnosed with PH and 13 healthy control subjects were included. Fast strain encoded and routine cine MRI was performed. The LS and CS at three RV levels were quantified and their relations with RVEF and BNP were investigated. Receiver operating characteristic (ROC) analysis was employed to assess the diagnostic utility of strain encoded MRI for the detection of low RVEF. Significant correlations with LS were observed for RVEF and BNP. Compared to CS, LS showed better correlation with RVEF. The mid-ventricular level of RV was the most sensitive site for evaluation of RV dysfunction. According to our ROC analysis, LS showed higher sensitivity and specificity to detect low RVEF. Compared to CS, LS showed stronger correlations with RVEF and BNP and could be a good detector of RV dysfunction in PH.

Differences in morphological features and minimum apparent diffusion coefficient values among breast cancer subtypes using 3-tesla MRI

PURPOSE To compare the morphology and minimum apparent diffusion coefficient (ADC) values among breast cancer subtypes. METHODS Ninety-three patients, who underwent breast MRI and collectively had 98 pathologically proven invasive carcinomas, were enrolled. Morphology was evaluated according to BIRADS-MRI. Minimum ADC was measured. Morphology and minimum ADC were compared among subtypes. Multivariate logistic regression analyses were used to identify the characteristics associated with different subtypes. RESULTS Oval/round shape was significantly associated with triple-negative (TN) cancer (TN vs. non-TN: 90.9% vs. 45.2%; p=0.0123). Rim enhancement was significantly less frequent in Luminal A (Luminal A vs. non-Luminal A: 34.2% vs. 76.1%; p=0.0003). The minimum ADC of Luminal A was significantly higher than that of Luminal B (HER2-negative) (834 vs. 748×10(-6)mm(2)/s; p<0.025). The minimum ADC of the TN-special type was significantly higher than that of TN-ductal (997 vs. 702×10(-6)mm(2)/s; p<0.025). On the multivariate analysis comparing the characteristics associated with Luminal A vs. Luminal B (HER2-negative), the internal enhancement characteristics of the mass and minimum ADC were significant factors. CONCLUSION Morphology and minimum ADC would be useful in distinguishing breast cancer subtypes.

Five-point Likert scaling on MRI predicts clinically significant prostate carcinoma

BackgroundTo clarify the relationship between the probability of prostate cancer scaled using a 5-point Likert system and the biological characteristics of corresponding tumor foci.MethodsThe present study involved 44 patients undergoing 3.0-Tesla multiparametric MRI before laparoscopic radical prostatectomy. Tracing based on pathological and MRI findings was performed. The relationship between the probability of cancer scaled using the 5-point Likert system and the biological characteristics of corresponding tumor foci was evaluated.ResultsA total of 102 tumor foci were identified histologically from the 44 specimens. Of the 102 tumors, 55 were assigned a score based on MRI findings (score 1: n = 3; score 2: n = 3; score 3: n = 16; score 4: n = 11 score 5: n = 22), while 47 were not pointed out on MRI. The tracing study revealed that the proportion of >0.5 cm3 tumors increased according to the upgrade of Likert scores (score 1 or 2: 33 %; score 3: 68.8 %; score 4 or 5: 90.9 %, χ2 test, p < 0.0001). The proportion with a Gleason score >7 also increased from scale 2 to scale 5 (scale 2: 0 %; scale 3: 56.3 %; scale 4: 72.7 %; 5: 90.9 %, χ2 test, p = 0.0001). On using score 3 or higher as the threshold of cancer detection on MRI, the detection rate markedly improved if the tumor volume exceeded 0.5 cm3 (<0.2 cm3: 10.3 %; 0.2-0.5 cm3: 25 %; 0.5-1.0 cm3: 66.7 %; 1.0 < cm3: 92.1 %).ConclusionsEach Likert scale favobably reflected the corresponding tumor’s volume and Gleason score. Our observations show that “score 3 or higher” could be a useful threshold to predict clinically significant carcinoma when considering treatment options.

Reduction of Bed Rest Time after Transfemoral Noncardiac Angiography from 4 Hours to 2 Hours: A Randomized Trial and a One-arm Study

PURPOSE To evaluate the feasibility of shortening the bed rest time from 4 hours to 2 hours after transfemoral noncardiac angiography with a 4-F sheath (outer diameter, 1.93 mm), a 5-F sheath (outer diameter, 2.27 mm), and a 4-F catheter. MATERIALS AND METHODS Patients were randomized into two groups, receiving either 2 or 4 hours of bed rest after hemostasis by manual compression of the puncture site. The authors evaluated the frequency of bleeding complications. An interim analysis was performed wherein 40 patients were assigned to each group. After the analysis, a single-arm 2-hour bed rest trial was conducted in an additional 115 procedures. RESULTS In the interim analysis, three of the 40 patients in the 4-hour group and none of the 40 patients in the 2-hour group developed minor bleeding within 2 hours after manual compression (P = .24). After 2 hours of bed rest, no bleeding complication was observed in either group. In the single-arm 2-hour bed rest trial, minor bleeding developed in one of the 115 procedures (0.8%). Through the study, minor bleeding occurred in four of the 195 total procedures (2%), and no major complications developed. The occurrence of a bleeding complication was significantly higher in patients with platelet counts of less than 100 x 10(9)/L than in the other patients (4/67 vs 0/128, P = .01). CONCLUSIONS Two hours of bed rest is feasible for patients undergoing transfemoral noncardiac angiography by using a 4-5-F sheath and/or a 4-F catheter, especially those with a normal platelet count.