Long-Term Prognosis and Related Factors in Patients with Cirrhosis Treated with Balloon-Occluded Retrograde Transvenous Obliteration.

INTRODUCTION: Balloon-occluded retrograde transvenous obliteration (BRTO) was developed as an effective treatment for gastric varices in patients with cirrhosis. Because liver fibrosis in these patients is assumed to be advanced, their prognosis is expected to be poor. In this study, we investigated the prognosis and characteristics of the patients. METHODS: We enrolled 55 consecutive patients with liver cirrhosis treated with BRTO between 2009 and 2021 at our department. To evaluate factors related to variceal recurrence and long-term prognosis, survival analysis was performed on 45 patients, excluding those who died within 1 month, had an unknown prognosis, or whose treatments were converted to other treatments. RESULTS: During a mean follow-up period of 2.3 years, esophageal varices recurred in 10 patients and could be treated endoscopically. Non-alcoholic steatohepatitis (NASH) was related to the variceal recurrence (hazard ratio [HR] = 4.27, 95% CI: 1.17-15.5, p = 0.028). The survival rate after the procedure at 1, 3, and 5 years was 94.2%, 74.0%, and 63.5%, respectively, and 10 patients died of hepatocellular carcinoma (n = 6), liver failure (n = 1), sepsis (n = 1), and unknown reasons (n = 2). The estimated glomerular filtration rate (eGFR) level was proved to be a significant poor prognostic factor (HR = 0.96, 95% CI: 0.93-0.99, p = 0.023). The comorbid hypertension (HTN) was the main cause of low eGFR, and HTN was also significantly related to survival (HR = 6.18, 95% CI: 1.57-24.3, p = 0.009). Most of the patients with HTN were treated with calcium channel blocker and/or angiotensin receptor blocker. CONCLUSION: The clinical course of patients with cirrhosis treated with BRTO was dependent on the metabolic factors including renal function, comorbid HTN, and NASH.

Pulsatility index of superficial temporal artery was associated with cerebral infarction after direct bypass surgery for moyamoya disease.

OBJECTIVE: Direct bypass surgery by superficial temporal artery (STA) - middle cerebral artery anastomosis is an established procedure for moyamoya disease (MMD). However, some patients may develop cerebral infarction (CI) due to the watershed shift phenomenon after the surgery. This study sought to investigate the correlation between the postoperative changes of STA flow as well as cerebral blood flow (CBF) and the incidence of CI after direct bypass surgery for MMD. METHODS: We conducted a retrospective study of 62 hemispheres in 50 subjects who underwent direct bypass surgery for MMD. All subjects underwent pre- and post-operative MR imaging, ultrasound evaluation of STA, and single-photon emission computed tomography. The presence of CI was correlated with preoperative CBF, the delta difference of each value of the STA between before and after the surgery, and the postoperative increase ratio of CBF. RESULTS: All bypass procedures were patent, and CI was observed in 4 cases (6.4%). There was no significant association between the incidence of CI and both pre- and post-operative CBF. However, there was a significant difference in delta pulsatility index (PI) of the STA between cases with or without CI (-0.38±0.22 and -0.87±0.63, respectively, p=0.03). Whereas, other factors did not show any significant differences between those with or without CI. CONCLUSIONS: A relatively high postoperative PI of the STA was significantly associated with the incidence of CI after direct bypass surgery for MMD. A larger study is needed to confirm these findings.

REBOA Zone Estimation from the Body Surface Using Semantic Segmentation.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an endovascular procedure for hemorrhage control. In REBOA, the balloon must be placed in the precise place, but it may be performed without X-ray fluoroscopy. This study aimed to estimate the REBOA zones from the body surface using deep learning for safe balloon placement. A total of 198 abdominal computed tomography (CT) datasets containing the regions of the REBOA zones were collected from open data libraries. Then, depth images of the body surface generated from the CT datasets and the images corresponding to the zones were labeled for deep learning training and validation. DeepLabV3+, a deep learning semantic segmentation model, was employed to estimate the zones. We used 176 depth images as training data and 22 images as validation data. A nine-fold cross-validation was performed to generalize the performance of the network. The median Dice coefficients for Zones 1-3 were 0.94 (inter-quarter range: 0.90-0.96), 0.77 (0.60-0.86), and 0.83 (0.74-0.89), respectively. The median displacements of the zone boundaries were 11.34 mm (5.90-19.45), 11.40 mm (4.88-20.23), and 14.17 mm (6.89-23.70) for the boundary between Zones 1 and 2, between Zones 2 and 3, and between Zone 3 and out of zone, respectively. This study examined the feasibility of REBOA zone estimation from the body surface only using deep learning-based segmentation without aortography.

Amyotrophic Lateral Sclerosis with Pallidonigroluysian Degeneration: A Clinicopathological Study.

OBJECTIVE: The pallidonigroluysian (PNL) system, the primary component of corticosubcortical circuits, is generally spared in amyotrophic lateral sclerosis (ALS). We evaluated the clinicopathological features of an unusual form of ALS with PNL degeneration (PNLD) and assessed whether ALS with PNLD represents a distinct ALS subtype. METHODS: From a cohort of 97 autopsied cases of sporadic ALS with phosphorylated 43kDa TAR DNA-binding protein (TDP-43) inclusions, we selected those with PNLD and analyzed their clinicopathological features. RESULTS: Eleven cases (11%) that showed PNLD were divided into 2 subtypes depending on the lesion distribution: (1) extensive type (n = 6), showing widespread TDP-43 pathology and multisystem degeneration, both involving the PNL system; and (2) limited type (n = 5), showing selective PNL and motor system involvement, thus being unclassifiable in terms of Brettschneider's staging or Nishihira's typing of ALS. The limited type showed a younger age at onset and predominant PNLD that accounted for the early development of extrapyramidal signs. The limited type exhibited the heaviest pathology in the subthalamus and external globus pallidus, suggesting that TDP-43 inclusions propagated via indirect or hyperdirect pathways, unlike ALS without PNLD, where the direct pathway is considered to convey TDP-43 aggregates from the cerebral cortex to the substantia nigra. INTERPRETATION: The PNL system can be involved in the disease process of ALS, either nonselectively as part of multisystem degeneration, or selectively. ALS with selective involvement of the PNL and motor systems exhibits unique clinicopathological features and TDP-43 propagation routes, thus representing a distinct subtype of ALS. ANN NEUROL 2020;87:302-312.

Location of embolization affects patency after coil embolization for pulmonary arteriovenous malformations: importance of time-resolved magnetic resonance angiography for diagnosis of patency.

OBJECTIVES: This study aimed to assess the diagnostic accuracy of computed tomography (CT) and time-resolved magnetic resonance angiography (TR-MRA) for patency after coil embolization of pulmonary arteriovenous malformations (PAVMs) and identify factors affecting patency. METHODS: Data from the records of 205 patients with 378 untreated PAVMs were retrospectively analyzed. Differences in proportional reduction of the sac or draining vein on CT between occluded and patent PAVMs were examined, and receiver operating characteristic analysis was performed to assess the accuracy of CT using digital subtraction angiography (DSA) as the definitive diagnostic modality. The accuracy of TR-MRA was also assessed in comparison to DSA. Potential factors affecting patency, including sex, age, number of PAVMs, location of PAVMs, type of PAVM, and location of embolization, were evaluated. RESULTS: The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of CT were 82%, 81%, 77%, 85%, and 82%, respectively, when the reduction rate threshold was set to 55%, which led to the highest diagnostic accuracy. The sensitivity, specificity, PPV, NPV, and accuracy of TR-MRA were 89%, 95%, 89%, 95%, and 93%, respectively. On both univariable and multivariable analyses, embolization of the distal position to the last normal branch of the pulmonary artery was a factor that significantly affected the prevention of patency. CONCLUSIONS: TR-MRA appears to be an appropriate method for follow-up examinations due to its high accuracy for the diagnosis of patency after coil embolization of PAVMs. The location of embolization is a factor affecting patency. KEY POINTS: • Diagnosis of patency after coil embolization for pulmonary arteriovenous malformations (PAVMs) is important because a patent PAVM can lead to neurologic complications. • The diagnostic accuracies of CT with a cutoff value of 55% and TR-MRA were 82% and 93%, respectively. • The positioning of the coils relative to the sac and the last normal branch of the artery was significant for preventing PAVM patency.

Natural History of Unruptured Visceral Artery Aneurysms Due to Segmental Arterial Mediolysis and Efficacy of Transcatheter Arterial Embolization: A Retrospective Multiinstitutional Study in Japan.

OBJECTIVE. The purpose of this study was to clarify the natural history of unruptured visceral artery aneurysms due to segmental arterial mediolysis and the efficacy of transcatheter arterial embolization. MATERIALS AND METHODS. Patients with a pathologic or clinical diagnosis of visceral artery aneurysms due to segmental arterial mediolysis between 2005 and 2015 were enrolled. For patients with clinical diagnoses, images were collected and assessed by central radiologic review. To clarify the natural history of unruptured aneurysms, the morphologic changes were assessed. The efficacy and safety of transcatheter arterial embolization for aneurysms due to segmental arterial mediolysis were evaluated. RESULTS. Forty-five patients with 123 aneurysms due to segmental arterial mediolysis were enrolled. Among the 123 aneurysms, 70 unruptured aneurysms were evaluated for natural history. Forty-five of the 70 (64%) aneurysms had no change in morphology. Among the other 25 aneurysms, nine (13% of the 70) were reduced in size, 13 (19%) disappeared, and three (4%) were newly found at follow-up. Aneurysms of the middle colic artery were ruptured in 10 of 11 (91%) cases. Transcatheter arterial embolization was performed on 45 aneurysms and was successful in all cases but caused slight arterial injury in three cases (6.7%). CONCLUSION. At initial diagnosis, unruptured aneurysms due to segmental arterial mediolysis are likely to be stable or to resolve, but the risk of rupture of aneurysms of the middle colic artery appears high. Transcatheter arterial embolization is a useful treatment, but careful manipulation is necessary.

Mixed Reality Visualization of Radiation Dose for Health Professionals and Patients in Interventional Radiology.

For interventional radiology, dose management has persisted as a crucially important issue to reduce radiation exposure to patients and medical staff. This study designed a real-time dose visualization system for interventional radiology designed with mixed reality technology and Monte Carlo simulation. An earlier report described a Monte-Carlo-based estimation system, which simulates a patient's skin dose and air dose distributions, adopted for our system. We also developed a system of acquiring fluoroscopic conditions to input them into the Monte Carlo system. Then we combined the Monte Carlo system with a wearable device for three-dimensional holographic visualization. The estimated doses were transferred sequentially to the device. The patient's dose distribution was then projected on the patient body. The visualization system also has a mechanism to detect one's position in a room to estimate the user's exposure dose to detect and display the exposure level. Qualitative tests were conducted to evaluate the workload and usability of our mixed reality system. An end-to-end system test was performed using a human phantom. The acquisition system accurately recognized conditions that were necessary for real-time dose estimation. The dose hologram represents the patient dose. The user dose was changed correctly, depending on conditions and positions. The perceived overall workload score (33.50) was lower than the scores reported in the literature for medical tasks (50.60) for computer activities (54.00). Mixed reality dose visualization is expected to improve exposure dose management for patients and health professionals by exhibiting the invisible radiation exposure in real space.

Prognostic Factors of Preoperative Examinations for Non-occlusive Mesenteric Ischemia: A Multicenter Retrospective Project Study Conducted by the Japanese Society for Abdominal Emergency Medicine.

BACKGROUND: Non-occlusive mesenteric ischemia (NOMI) has a high mortality rate, but the analyses of preoperative prognostic factors for improving survival in patients suspected of having NOMI are scarce. We aimed to analyze the prognostic factors of preoperative examinations for NOMI. METHODS: The clinical data of 224 patients with NOMI were retrospectively collected for a multicenter survey. Clinicophysiological factors were compared between the survivors and non-survivors (N = 107/117) and between the operative and non-operative cases (N = 180/44) by univariate analysis using chi-square test and multivariate analysis using Cox proportional hazard models. In the operative cases, the prognostic operative factors were also analyzed. RESULTS: The overall mortality rate for NOMI was 52.2%. There were 129 male and 95 female patients. The mean age was 71.23 (14-94) years. Univariate analysis showed that cardiovascular complication, shock, abdominal pain, average blood pressure, systemic inflammatory response syndrome, aspartic aminotransferase, alanine transaminase, creatine phosphokinase, lactate dehydrogenase, base excess, prothrombin time-international normalized ratio, D-dimer, and fibrinogen degradation products were independent prognostic factors. Multivariate analysis showed that average blood pressure and base excess were independent prognostic factors. Among patients undergoing surgery, those with bowel resection had better prognosis than those without bowel resection, but those with long bowel resection had worse prognosis than those with short resection. Additional postoperative treatment was not effective compared with operation alone (P = 0.011). CONCLUSIONS: Prognostic factors of preoperative examinations for NOMI were average blood pressure and base excess. Patients with long bowel resection should be carefully monitored owing to their poor prognosis.

Effects of intravenous injection of indocyanine green on the oxygen reserve index (ORi™).

PURPOSE: The oxygen reserve index (ORi™) is a parameter used for the noninvasive evaluation of arterial partial pressure of oxygen (PaO2), specifically in the 100-200 mmHg range. We aimed to report on the impact of indocyanine green (ICG) on the ORi™. METHODS: In this study, we retrospectively examined patients who underwent neurosurgery between April and July 2019 and assessed the impact of ICG on ORi™. We excluded patients who did not use ICG or who were not examined for ORi™. The dose and timing of ICG administration were determined by a neurosurgeon. The changes in ORi™ were measured for up to 30 min. RESULTS: We analyzed ten patients and found that the ORi™ increased to 1.00 in all of them. The median time for ORi ™ to rise to 1.00 after ICG administration was 2 min (range 1-4). After rising to 1.00, ORi ™ decreased and took 27 min to return to the pre-dose value. CONCLUSION: It is important to consider the initial rapid increase and subsequent slow decrease in ORi™ when using ICG during surgery.

Evaluation of Outcomes Using a Tablet-Based System to Support Glycemic Management Workflow Operations: A Retrospective Observational Study.

The treatment of hospitalized patients with type 2 diabetes requires glycemic management to maintain the patients' blood glucose levels within a normal range. We developed a blood glucose management system (BGM) system in 2015, which is a tablet-based workflow support system. This system enables medical staff to continually confirm the physicians' instructions by measuring the blood glucose levels while using a tablet terminal.In this study, we examined electronic medical records (EMRs) to evaluate the usage frequency of the BGM system and the time required for the glycemic management workflow in comparison to conventional PC terminals in a large hospital setting. The data includes 197,927 blood glucose level measurements that were taken in the general wards of Tottori University Hospital between January 2016 and June 2017. The usage frequency of the glycemic management workflow while using the BGM system was 145,864 times (approximately 74% of the total blood glucose measurements). The mean time until the completion of the glycemic management workflow in the case of hyperglycemia was 16 min 33 s, which is 26% shorter than using a PC terminal for treatment that involves injection or infusion (1454 times). The BGM system is proactively utilized by medical staff, thereby improving the operating efficiency. The results of this study indicate that the BGM system installed on tablet terminals can improve the efficiency in large-scale medical institutions that treat patients with diabetes.

[Congenital Dermal Sinus with Dermoid Cyst Complicated by Brain Abscess: A Case Report].

Congenital dermal sinus(CDS)is a rare entity of spinal dysraphism, caused by the focal failure of disjunction leading to adhesion between the cutaneous and neural ectoderm. Some reports found that tumors, such as dermoid and epidermoid cysts, meningitis and subdural abscess are often complicated by CDS. A 1-year-old girl was referred to our department for CDS with a dermoid cyst complicated by brain and subdural abscesses. Diffusion weighted imaging and gadolinium-diethylenetriamine penta-aceticacid administration revealed ring-enhancing lesions, suggesting brain abscess, in the left temporal lobe, and subdural abscesses on the bilateral middle cranial bases. T1-and T2-weighted lumbar magnetic resonance imaging revealed CDS. With a preoperative diagnosis of CDS with brain and subdural abscesses, resection of CDS was performed after draining the brain abscess twice. The CDS extended into the spinal canal and it was completely exercised. We then performed sub-total resection of the dermoid cyst in the subdural space. Recent reports showed that dermoid cysts are related to CDS infection and deterioration of the infection, as seen in this case. Complication of dermoid cysts is an important consideration during CDS treatment. While the mechanism of the development of brain abscess in CDS patients has been unclear, this rare but important case revealed the mechanism to be the direct spread of inflammation via CDS.

COQ2 variants in Parkinson's disease and multiple system atrophy.

Coenzyme Q2, polyprenyltransferase (COQ2) variants have been reported to be associated with multiple system atrophy (MSA). However, the relationship between COQ2 variants and familial Parkinson's disease (PD) remains unclear. We investigated the frequency of COQ2 variants and clinical symptoms among familial PD and MSA. We screened COQ2 using the Sanger method in 123 patients with familial PD, 52 patients with sporadic PD, and 39 patients with clinically diagnosed MSA. Clinical information was collected from medical records for the patients with COQ2 variants. Allele frequencies of detected rare non-synonymous variants were compared by public database of the Exome Aggregation Consortium (ExAC) and Japanese genetic variation database, using Fisher's exact test. We detected two probands with rare variants in COQ2, the p.P157S from Family A, whose patient was clinically diagnosed as having juvenile PD, and the p.H15 N/p.G331S from Family B, whose patients shared common symptoms of PD. Furthermore, in an association study comparing these familial PD and MSA cases with a public variant database, eight non synonymous variants were detected in COQ2. Three of these were very rare variants, namely, p.P157S, p.L261Qfs*4, and p.G331S, and one variant, p.G21S, was found to show a significant association with familial PD. COQ2 variants rarely may associate with the disease onset of familial PD. Our findings contribute to an understanding of COQ2 variants in neurodegenerative disorders.

Gadoxetic acid disodium-enhanced MR imaging of cholangiolocellular carcinoma of the liver: imaging characteristics and histopathological correlations.

OBJECTIVES: To review the gadoxetic acid disodium (EOB)-enhanced magnetic resonance (MR) imaging features of cholangiolocellular carcinoma (CoCC) of the liver and compare them with those of hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). METHODS: EOB-enhanced MR images of 19 patients with CoCC, 23 with ICC, and 51 with HCC were retrospectively evaluated qualitatively and quantitatively. Univariate and multivariate analyses were performed to determine the characteristic MR features of CoCC with histopathological-imaging correlation. RESULTS: Multivariate logistic regression analysis showed that dot-/band-shaped internal enhancement during the arterial and portal phases (P < 0.001), and larger arterial ring enhancement ratio (CoCC, 0.13 ± 0.04; ICC, 0.074 ± 0.04; P = 0.013) were significantly independently associated with CoCC in contrast to ICC, whereas several MR features including progressive enhancement during the portal and late phases (P < 0.001), target appearance in the hepatocyte phase (P = 0.004), and vessel penetration (P = 0.013) were significantly more frequently associated with CoCC than HCC. The dot-/band-like internal enhancement (78.9% of CoCCs) histopathologically corresponded to the tumour cell nest with vascular proliferations and retained Glisson's sheath structure. CONCLUSIONS: EOB-enhanced MR features of CoCC largely differ from those of HCC but are similar to those of ICC. However, the finding of thicker arterial ring enhancement with dot-/band-like internal enhancement could help differentiate CoCC from ICC. KEY POINTS: • Gadoxetic acid-enhanced MR features of cholangiolocellular carcinoma (CoCC) resembled those of intrahepatic cholangiocarcinoma (ICC). • Gadoxetic acid-enhanced MR features of CoCC largely differed from those of hepatocellular carcinoma. • Dot-/band-like internal enhancement of CoCC may be helpful for differentiating from ICC. • Arterial ring enhancement of CoCC was larger than that of ICC.

Fewer REBOA complications with smaller devices and partial occlusion: evidence from a multicentre registry in Japan.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) performed by emergency physicians has been gaining acceptance as a less invasive technique than resuscitative thoracotomy. OBJECTIVE: To evaluate access-related complications and duration of occlusions during REBOA. METHODS: Patients with haemorrhagic shock requiring REBOA, from 18 hospitals in Japan, included in the DIRECT-IABO Registry were studied. REBOA-related characteristics were compared between non-survivors and survivors at 24 hours. 24-Hour survivors were categorised into groups with small (≤8 Fr), large (≥9 Fr) or unusual sheaths (oversized or multiple) to assess the relationship between the sheath size and complications. Haemodynamic response, occlusion duration and outcomes were compared between groups with partial and complete REBOA. RESULTS: Between August 2011 and December 2015, 142 adults undergoing REBOA were analysed. REBOA procedures were predominantly (94%) performed by emergency medicine (EM) physicians. The median duration of the small sheath (n=53) was 19 hours compared with 7.5 hours for the larger sheaths (P=0.025). Smaller sheaths were more likely to be removed using external manual compression (96% vs 45%, P<0.001). One case of a common femoral artery thrombus (large group) and two cases of amputation (unusual group) were identified. Partial REBOA was carried out in more cases (n=78) and resulted in a better haemodynamic response than complete REBOA (improvement in haemodynamics, 92% vs 70%, P=0.004; achievement of stability, 78% vs 51%, P=0.007) and allowed longer occlusion duration (median 58 vs 33 min, P=0.041). No statistically significant difference in 24-hour or 30-day survival was found between partial and complete REBOA. CONCLUSION: In Japan, EM physicians undertake the majority of REBOA procedures. Smaller sheaths appear to have fewer complications despite relatively prolonged placement and require external compression on removal. Although REBOA is a rarely performed procedure, partial REBOA, which may extend the occlusion duration without a reduction in survival, is used more commonly in Japan.

Diffusion kurtosis imaging of the pancreas for the assessment of HbA1c levels.

PURPOSE: To evaluate the feasibility of diffusion kurtosis (DK) imaging of the pancreas for the assessment of hemoglobin (Hb) A1c values. MATERIALS AND METHODS: Our Institutional Review Board approved this prospective study and written informed consent was obtained. In all, 102 consecutive patients with suspected pancreatic disease underwent magnetic resonance imaging (MRI), including DK imaging. Patients were classified into three groups according to American Diabetes Association criteria: HbA1c < 5.7% (group 1), 5.7% ≤ HbA1c < 6.5% (group 2), and HbA1c ≥ 6.5% (group 3). Mean kurtosis (MK) and apparent diffusion coefficient (ADC) of pancreatic parenchyma were computed. MRI measurements and HbA1c values were then compared. RESULTS: HbA1c values positively correlated with MK (r = 0.66, P < 0.0001). Group 3 was significantly (P < 0.05) higher (P < 0.05) in MK than groups 1 and 2. The sensitivity, specificity, and area under the ROC curve of the MK for the detection of group 3 were 90%, 88%, and 0.92, respectively. CONCLUSION: The MK measurement on DK imaging of the pancreas could be a potential biomarker for assessing HbA1c level.

[The Efficacy of Soluble Fibrin Monomer Complex (SFMC) for Diagnosis of Aortic Dissection (AD)].

BACKGROUND: Some biomarkers are helpful for AD diagnosis. Although many studies on efficacy of D-dimer have been reported, there are few reports about SFMC. Therefore we conducted a retrospective comparative study of efficacy of SFMC and D-dimer for diagnosis of AD. METHODS: Nineteen patients diagnosed as AD in the emergency visit were examined. Patients with cardiopulmonary arrest on arrival were excluded. These patients were classified into three patterns as follows, Stanford A or B, terms of arriving at hospital, and closing type or patent type. The value of D-dimer and SFMC were measured at the time of the first medical examination, and comparative study of both biomarkers was carried out in each groups. RESULTS: Background of patients were not significantly different in three studies. SFMC and D-dimer showed no significant difference between Stanford A and B. Short-terms SFMC is significantly higher than long-terms. But D-dimer showed no significant difference in each comparison. Patent type of SFMC showed higher than closing type. But D-dimer showed no significant difference between patent type and closing type. CONCLUSIONS: SFMC showed earlier response to AD than D-dimer. Measuring SFMC coupled with D-dimer is helpful for AD diagnosis.

Low-Iodine-Load and Low-Tube-Voltage CT Angiographic Imaging of the Kidney by Using Bolus Tracking with Saline Flushing.

PURPOSE: To prospectively determine the feasibility of low-iodine-load and low-tube-voltage computed tomographic (CT) angiographic imaging of the kidney and to evaluate the opacification and image quality compared with moderate-iodine-load and high-iodine-load techniques. MATERIALS AND METHODS: Institutional review board approval and written informed consent was obtained. One hundred thirteen consecutive patients randomly underwent three protocols for dual-phase renal CT angiographic imaging: high-iodine-load (600 mg iodine per kilogram of body weight at 120 kVp); moderate-iodine-load (400 mg iodine per kilogram of body weight at 80 kVp); and low-iodine-load (contrast agent injection initially prepared at 400 mg iodine per kilogram of body weight but stopped immediately after bolus-tracking trigger at 80 kVp) scanning. CT numbers of vessels and kidneys were measured. CT numbers and signal-to-noise ratio (SNR) were compared with one-way analysis of variance and posthoc Tukey-Kramer test and depiction of vessels and image noise, with Kruskal-Wallis test and pair-wise Mann-Whitney test with Bonferroni correction. RESULTS: Mean iodine weight administered was significantly reduced in order of low- (16.4 g), moderate- (23.5 g), and high-iodine-load (33.7 g) protocols (P < .001). Mean CT numbers of abdominal aorta, renal artery, and renal cortex in first phase were significantly lower with high-iodine-load protocol (308, 274, and 132 HU, respectively) than with moderate- (347, 334, and 156 HU, respectively; P = .001-.006) or low-iodine-load (362, 316, and 161 HU, respectively; P = .001-.003) protocol. Mean CT number of renal vein in second phase was significantly lower with low-iodine-load protocol (223 HU) than with moderate- (299 HU; P < .001) or high-iodine-load (258 HU; P = .020). Mean SNR of renal medulla in second phase was significantly lower (P = .019) with moderate-iodine-load protocol (mean SNR, 7.2) than with high-iodine-load protocol (mean SNR, 10.0). No significant difference in image quality grades was found between high-iodine-load (mean grade, 2.6-2.9), moderate-iodine-load (mean grade, 2.6-3.0), and low-iodine-load (mean grade, 2.6-2.9) protocols (P = .018-.31). CONCLUSION: Combined application of low-iodine-load, bolus tracking with saline flushing, and low-tube-voltage scanning is feasible and resulted in substantial reduction of iodine dose for renal CT angiographic imaging without compromising image quality.

18-F fluorodeoxyglucose uptake in positron emission tomography as a pathological grade predictor for renal clear cell carcinomas.

OBJECTIVES: To evaluate the usefulness of Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18-F FDG-PET/CT) in the prediction of Fuhrman pathological grades of renal clear cell carcinoma (cRCC). METHODS: This retrospective study was approved by our institutional review board, and written informed consent was waived. Thirty-one patients with pathologically proven cRCC underwent 18-F FDG-PET/CT for tumour staging. Maximum standardized uptake value of cRCC (tumour SUVmax) and mean SUV of the liver and spleen (liver and spleen SUVmean) were measured by two independent observers. Tumour SUVmax, tumour-to-liver SUV ratio, and tumour-to-spleen SUV ratio were correlated with the pathological grades. RESULTS: Logistic analysis demonstrated that only the tumour-to-liver SUV ratio was a significant parameter for differentiating high-grade (Fuhrman grades 3 and 4) tumours from low-grade (Fuhrman grades 1 and 2) tumours (P = 0.007 and 0.010 for observers 1 and 2, respectively). Sensitivity, specificity, and positive and negative predictive values for detecting tumours of Fuhrman grades 3 and 4 were 64, 100, 100, and 77%, respectively, for observer 1, and 79, 88, 85, and 83%, respectively, for observer 2. CONCLUSIONS: The tumour-to-liver SUV ratio with 18-F FDG-PET/CT appeared to be a valuable imaging biomarker in the prediction of high-grade cRCC. KEY POINTS: • Tumour SUV max was correlated with the Fuhrman grades. • High-grade tumours have significantly higher SUV max than low-grade tumours. • Tumour-to-liver SUV ratio is useful in the prediction of high-grade cRCC.

Diffusion kurtosis imaging to assess response to treatment in hypervascular hepatocellular carcinoma.

OBJECTIVE: The objective of our study was to compare diffusion kurtosis imaging (DKI) with conventional diffusion-weighted imaging (DWI) for assessing the response to treatment in hypervascular hepatocellular carcinoma (HCC). SUBJECTS AND METHODS: Sixty-two consecutive patients with treated or untreated hypervascular HCC underwent MRI of the liver including DKI (b values of 0, 100, 500, 1000, 1500, and 2000 s/mm(2)). The mean kurtosis (MK) and apparent diffusion coefficient (ADC) values of the hepatic parenchyma and of the HCCs were computed. The detectability of viable HCC based on MK and ADC values was compared. We also assessed the correlation between Child-Pugh grades and MK or ADC values. RESULTS: For a total of 112 HCC nodules (viable, n = 63; nonviable, n = 49), the MK value was significantly higher for the viable group (mean ± SD, 0.81 ± 0.11) than for the non-viable group (0.57 ± 0.11) (p < 0.001). The mean ADC value was significantly lower for the viable group (1.44 ± 0.42 × 10(-3) mm(2)/s) than for the nonviable group (1.94 ± 0.52 × 10(-3) mm(2)/s) (p < 0.001). The sensitivity, specificity, and AUC of the ROC curve for the assessment of HCC viability were greater (p < 0.001) using MK (85.7%, 98.0%, and 0.95, respectively; cutoff value = 0.710) than using ADC (79.6%, 68.3%, and 0.77, respectively; cutoff value = 1.535 × 10(-3) mm(2)/s). Although the ADC of hepatic parenchyma was lower in patients with Child-Pugh grade B or C disease than in those with grade A disease (p = 0.02), no significant difference in MK (p = 0.45) was found among the Child-Pugh grades. CONCLUSION: DKI can be a new option for the assessment of posttherapeutic response in HCC.