Assessment of first-time and repeated acute adverse reactions to gadolinium-based contrast agents in MRI: A retrospective study.

PURPOSE: To identify gadolinium-based contrast agents (GBCAs)-related and patient-related risk factors for acute adverse reactions (AARs), and to examine the incidence and severity of repeated AARs. METHODS: This study retrospectively evaluated all intravenous GBCA injections in MRI studies at a single institution from January 2012 to September 2019. First-time AARs in patients without a past history of AARs and risk factors were assessed using multivariable regression models with generalized estimating equations. For patients with a past history of AAR(s), we evaluated the incidence of repeated AARs using the Fisher's exact test, as well as the severity of these repeated AARs. RESULTS: First-time AARs occurred in 129 of 41,827 GBCA injections (0.31 %; 0.70 % of 18,431 patients). With gadoterate meglumine as the reference, the odds ratio (OR) for allergic-like reactions to three GBCAs ranged from 3.27 to 8.03 (p = 0.012 to <0.001). For chemotoxic reactions, the OR was 3.75 (p = 0.001) for gadoteridol. Outpatients had a lower OR for chemotoxic reactions, while higher ORs were observed in head/neck and breast MRI (p < 0.05). The OR for age was 0.99 (p < 0.05). Patients with a past history of AAR(s) had a 3.6 % incidence of mild repeated AARs for all GBCA, significantly higher than the 0.31 % in first-time AARs (p < 0.001). No effectiveness was found for steroid premedication. CONCLUSION: The occurrence of first-time AARs was related to the GBCA used and other factors. The incidence of repeated AARs was higher than first-time AARs, though all were mild in severity.

Efficacy of 18F-Fluorodeoxyglucose positron emission tomography/computed tomography for detecting renal cell carcinoma in patients with end-stage renal disease.

PURPOSE: Dialysis patients are at an increased risk of developing renal cell carcinoma (RCC); however, differentiating between RCC and benign cysts can sometimes be difficult using modalities, such as computed tomography (CT) and ultrasonography. 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET)/CT efficiently detects malignant tumors; however, physiological accumulation of FDG in the kidney limits its efficacy in detecting renal tumors. However, in patients with severely impaired renal function, the renal accumulation of FDG is decreased, possibly improving the detection of renal malignancies in this patient population. This study evaluated the usefulness of FDG-PET/CT as a screening tool for detecting RCC in patients with end-stage renal disease. MATERIALS AND METHODS: This prospective study recruited 150 participants from 2012 to 2016 who were on dialysis or underwent renal transplantation and were on dialysis until transplantation. FDG-PET/CT was performed to screen for RCC. Three radiologists independently evaluated the images. No protocol was defined for the additional management of positive examinations, leaving decisions to the discretion of each participant. Negative examinations were observed until the end of 2019. RESULTS: In total, 150 participants (mean age, 58 ± 13 years; 105 men) underwent FDG-PET/CT. Twenty patients (13.4%) were diagnosed as positive. Fifteen patients underwent additional examinations and/or procedures, and RCC was found in seven patients. Of the four patients who underwent surgical resection, the pathological results were clear cell RCC in one, papillary RCC in one, and acquired cystic disease-associated RCC in two. Two participants were diagnosed with RCC on bone biopsy, and one was diagnosed on dynamic CT but opted for observation. The sensitivity, specificity, and negative predictive value were 100%, 93.9%, and 100%, respectively. CONCLUSION: FDG-PET/CT was useful for detecting RCC in patients with end-stage renal disease. Our findings show the potential use of FDG-PET/CT as a screening tool for RCC in this patient population.

Striatal dopamine transporter binding differs between dementia with Lewy bodies and Parkinson's disease with dementia.

123I-ioflupane single-photon emission computed tomography (SPECT) is a highly sensitive and established neuroimaging technique for parkinsonian syndromes (PS). However, differentiating PS by visual inspection or analysis of regions of interest is challenging. To date, image analysis has not been able to differentiate dementia with Lewy bodies (DLB) from Parkinson's disease with dementia (PDD). This study aimed to differentiate PS based on the characteristics of striatal dopamine transporter (DAT) binding using voxel-based analysis. We acquired 123I-ioflupane SPECT data from patients with DLB (n = 30), Parkinson's disease (PD; n = 122), PDD (n = 19), multiple system atrophy with predominant parkinsonism (MSA-P; n = 18), and progressive supranuclear palsy (PSP; n = 45). DAT binding was reduced in the posterior striatum of patients with PD and PDD, whereas it was similar in MSA-P, PSP, and DLB. Hippocampal atrophy, visually evaluated by cerebral magnetic resonance imaging, did not affect striatal DAT binding in DLB. DAT binding in the anterior striatum was inversely correlated with the severity of parkinsonism in PD and PDD but not in DLB. Thus, the appearance of striatal DAT binding might indicate different pathological processes in DLB and PDD.

Clinical features and risk factors of iodinated contrast media (ICM)-induced anaphylaxis.

PURPOSE: To evaluate the clinical features and risk factors of iodinated contrast media (ICM)-induced anaphylaxis. METHODS: This retrospective study included all patients undergoing contrast-enhanced computed tomography (CT) with intravenous ICM administration (iopamidol, iohexol, iomeprol, iopromide, ioversol) at our hospital between April 2016 and September 2021. Medical records of patients who experienced anaphylaxis were reviewed, and the multivariable regression model using generalized estimating equations was employed to eliminate the effect of intrapatient correlation. RESULTS: Of the 76,194 ICM administrations (44,099 men [58 %] and 32,095 women; age, median, 68 years) to 27, 696 patients, anaphylaxis occurred in 45 cases in 45 different patients (0.06 % of administration and 0.16 % of patients), all with onset within 30 min after administration. Thirty-one (69 %) had no risk factors for ADRs, including 14 (31 %) who had previously used the same ICM that caused anaphylaxis. Thirty-one patients (69 %) had a history of ICM use without any ADRs. Four patients (8.9 %) received oral steroid premedication. The only factor associated with anaphylaxis was the type of ICM, with an odds ratio (OR) of 6.8 (p < 0.001) for iomeprol with iopamidol as a reference. No significant differences in OR of anaphylaxis were found for patients' age, sex, or premedication. CONCLUSION: The overall incidence of anaphylaxis due to ICM was very low. More than half of the cases had no risk factors for ADRs and had no ADRs on past ICM administration, although the ICM type was associated with a higher OR.

Contrast-induced anaphylaxis: does it occur in the medical environment and is it being responded to appropriately?

PURPOSE: To analyze the appropriateness of primary response for anaphylaxis due to iodinated contrast media (ICM) or gadolinium-based contrast agents (GBCA). MATERIALS AND METHODS: This retrospective study included all patients in whom intravenous contrast agents (five types of ICMs and four types of GBCAs) were administered at our hospital between April 2016 and September 2021. For the patients who developed anaphylaxis, we obtained data on the time records of contrast injection, anaphylaxis onset, and intramuscular adrenaline (epinephrine) administration. RESULTS: Of the 76,555 ICM and 30,731 GBCA administrations, anaphylaxis occurred in 49 cases (0.05%), and in 48 cases (98.0%) the onset was within 30 min after administration with widely distributed times (median, 7.5 min; interquartile range, 4.5-10.8 min; max, 26 min). Intramuscular adrenaline administration was performed in 43 cases (87.8%), and this was done within five minutes after the onset in 37 cases (75.5%). Only in 24 cases (49.0%), there were time records of both the onset and adrenaline administration (if performed). CONCLUSION: Anaphylaxis occurred within 30 min after contrast injection in the majority of the cases, but times were widely distributed. Only in 75.5% of cases, appropriate primary treatment was performed, and the importance of keeping exact time records in patients' charts should be re-emphasized.

Quantitative CT analysis of interstitial pneumonia in anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis: a single center, retrospective study.

INTRODUCTION: This study aimed to assess the utility of quantitative high-resolution computed tomography (HRCT) for determining the clinical course of anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis-associated interstitial lung disease (MDA5+ ILD). METHOD: This study retrospectively analyzed the data of 34 patients with MDA5+ ILD to determine the association between the clinical findings and extent of ILD via quantitative CT analysis at baseline and short-term follow-up. Quantified HRCT scores were evaluated as the lung severity score (LSS), percentage of opacity, and percentage of high opacity. RESULTS: Thirty-four patients underwent follow-up CT scans 35 (range: 14-78) days after diagnosis. Patients who died of rapidly progressive ILD had higher LSS (p < 0.01), percentage of opacity (p < 0.01), percentage of high opacity (p = 0.01), total ground-glass opacity score (p = 0.01), serum C-reactive protein (CRP) (p = 0.03), and alveolar-arterial oxygen difference (Aa-DO2) (p = 0.01) at follow-up than those who survived. Quantified HRCT scores correlated with serum CRP and Aa-DO2 levels at follow-up. LSS at follow-up (AUC = 0.844, p < 0.01) was the best predictor of death in MDA5+ ILD patients. Patients with an LSS of > 6.5 at follow-up had higher mortality than those with an LSS of ≤ 6.5, especially when receiving triple therapy. In multivariate analysis, an LSS of > 6.5 at follow-up was significantly associated with a poor outcome. CONCLUSIONS: Quantitative CT analysis of MDA5+ ILD is useful for the objective assessment of respiratory status and disease activity. Short-term HRCT evaluation, particularly LSS, is most important in predicting its clinical course during triple therapy. Key Points • Quantitative CT analysis plays an important role in evaluating the clinical course of anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis-associated interstitial lung disease (MDA5+ ILD). • Quantified HRCT scores, particularly lung severity score, at short-term intervals from diagnosis can help to predict prognosis after triple therapy in MDA5+ ILD.

Evaluation of Threshold Dose of Damaged Hepatic Tissue After Carbon-Ion Radiation Therapy Using Gd-EOB-DTPA-Enhanced Magnetic Resonance Imaging.

PURPOSE: To evaluate the threshold dose and associated factors using signal-intensity changes in the irradiated area after carbon-ion radiation therapy (C-ion RT) for patients with liver cancer. METHODS AND MATERIALS: Patients treated for the first time with C-ion RT for malignant liver tumors and followed up with 3-Tesla gadoxetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) 3 months after treatment completion were retrospectively enrolled. The volume of focal liver reaction (FLR), a low-intensity area in the hepatobiliary phase of Gd-EOB-DTPA after treatment, was measured. Corrected FLR (cFLR) volume, defined as FLR corrected for changes in tumor volume from before to after treatment, was calculated, and the threshold dose was determined by applying the cFLR volume in the dose-volume histogram. To evaluate potential mismatch in fusion images of planning computed tomography and follow-up MRI, the concordance coefficient (CC) was measured, and patients with a CC < 0.7 were excluded. Sixty patients were included. Multiple regression analysis was performed with the threshold dose as the objective variable and the age, dose, number of fractionations, Child-Pugh score, pretreatment liver volume, and pretreatment tumor volume as explanatory variables. The Student t test or Mann-Whitney U test was used as required. RESULTS: The median threshold doses for each number of dose fractionations (4 fractions, 12 fractions, and overall) were 51.6, 51.9, and 51.8 Gy (relative biological effectiveness [RBE]), respectively, in patients categorized as Child-Pugh class A and 27.0, 28.8, and 27.0 Gy (RBE), respectively, in patients categorized as Child-Pugh class B. In the multiple-regression analysis, only the Child-Pugh score was significant (P < .001). The number of dose fractionations was not statistically significant. CONCLUSIONS: Although few patients in the study had decreased liver function, baseline liver function was the only factor significantly associated with the median threshold dose. These findings facilitate appropriate patient selection to receive C-ion RT for malignant hepatic tumors.

Reliability of ultrasound hepatorenal index and magnetic resonance imaging proton density fat fraction techniques in the diagnosis of hepatic steatosis, with magnetic resonance spectroscopy as the reference standard.

PURPOSE: To evaluate the reliability of ultrasound hepatorenal index (US-HRI) and magnetic resonance imaging proton density fat fraction (MRI-PDFF) techniques in the diagnosis of hepatic steatosis, with magnetic resonance spectroscopy proton density fat fraction (MRS-PDFF) as the reference standard. MATERIALS AND METHODS: Fifty-two adult volunteers (30 men, 22 women; age, 31.5 ± 6.5 years) who had no history of kidney disease or viral/alcoholic hepatitis were recruited to undergo abdominal US, MRI, and MRS examinations. US-HRI was calculated from the average of three pairs of regions of interest (ROIs) measurements placed in the liver parenchyma and right renal cortex. On MRI, the six-point Dixon technique was employed for calculating proton density fat fraction (MRI-PDFF). An MRS sequence with a typical voxel size of 27 ml was chosen to estimate MRS-PDFF as the gold standard. The data were evaluated using Pearson's correlation coefficient and receiver operating characteristic (ROC) curves. RESULTS: The Pearson correlation coefficients of US-HRI and MRI-PDFF with MRS-PDFF were 0.38 (p = 0.005) and 0.95 (p<0.001), respectively. If MRS-PDFF ≥5.56% was defined as the gold standard of fatty liver disease, the areas under the curve (AUCs), cut-off values, sensitivities and specificities of US-HRI and MRI-PDFF were 0.74, 1.54, 50%, 91.7% and 0.99, 2.75%, 100%, 88.9%, respectively. The intraclass correlation coefficients (ICCs) of US-HRI and MRI-PDFF were 0.70 and 0.85. CONCLUSION: MRI-PDFF was more reliable than US-HRI in diagnosing hepatic steatosis.

The effect of abolishing instructions to fast prior to contrast-enhanced CT on the incidence of acute adverse reactions.

OBJECTIVES: To evaluate the effect of abolishing instructions to fast prior to contrast-enhanced CT on acute adverse reactions (AARs). METHODS: In our institution, we instructed patients to fast one meal before contrast-enhanced CT examinations. However, we abolished these instructions at the end of March 2019, and solid food intake was not restricted before contrast-enhanced CT after this date. The differences in the incidence of AARs before (December 2015-November 2018, n = 43,927) and after (April 2019-March 2020, n = 14,676) abolishing instructions to fast were compared. We allowed 4 months (December 2018-March 2019) for this policy change to fully permeate the CT referrals. The medical records of patients who vomited were retrospectively reviewed by one of the authors for notations of aspiration or aspiration pneumonia attributable to vomiting. RESULTS: The overall incidence of AARs before (1.60%, n = 705) and after abolition (1.40%, n = 205) did not change significantly. As the chemotoxic reactions, the incidence of nausea decreased significantly (0.31 to 0.18%, p = 0.006). The incidence of vomiting did not change (0.12 to 0.16%), and there were no cases of aspiration pneumonia attributable to vomiting during the study period. The incidence of severe hypersensitivity/allergy-like reactions did not change (0.06 to 0.05%). CONCLUSIONS: Abolishing instructions to fast decreased the incidence of nausea, but did not affect the incidence of vomiting. No cases of aspiration pneumonia attributable to vomiting were found. Our study confirmed that fasting is not required prior to contrast-enhanced CT.

[Improved Neural Imaging Sequence and Comparison with Conventional Methods].

The purpose of this study was to improve the contrast between the nerves and blood by reconsidering the imaging parameters of the sampling perfection with application-optimized contrasts using different flip angle evolutions (SPACE) method, and to compare it with conventional methods, including the constructive interference in steady state (CISS) and T2-weighted SPACE (T2-SPACE) methods. In the phantom study, the repetition time (TR), echo time (TE), flip angle (FA), and turbo factor (TF) of SPACE were varied using the restore pulse. The parameters for which the nerve-blood contrast (C1) and cerebrospinal fluid-nerve contrast (C2) were equal were selected. Though multiple conditions resulted in C1 and C2 equivalence, we determined/set the TR=500 ms, TE=21 ms,  FA=120°, and  TF=30, considering the acquisition time, specific absorption rate (SAR), and artifacts. This sequence was called "short TR and short TE SPACE with restore pulse (SSSR)". In the phantom and healthy volunteer studies, the contrast between the nerves and blood in the SSSR method was statistically superior in both the physical and visual assessments compared with conventional methods. In the healthy volunteer study, C1 improved from 0.08 for CISS and 0.18 for T2-SPACE to 0.43 for SSSR. This is because the nerve signals in conventional methods were low due to the heavy T2-weighted, while those in the SSSR method were high due to the short TE and effect of the restore pulse. In conclusion, the contrast between the nerves and blood was significantly higher in the SSSR method compared with conventional methods.

Possible solution for the problem of unread image interpretation reports: the "Gunma University Star Search".

PURPOSE: To propose a new strategy to prevent communication errors caused by unread radiology reports. MATERIALS AND METHODS: Medical emergencies were prefixed with triple stars on radiology reports, and the attending physician was contacted by telephone. Semi-emergencies (medical issues needing addressing within 2 weeks) were prefixed with double stars. Two weeks later, the duty radiologist would search the double-starred reports, and reviewed relevant patient charts to confirm that the information had been appropriately understood and acted upon. If not, the duty radiologist contacted the referral physician by telephone. One year after implementing this strategy, we retrospectively evaluated 1-year worth of data for all the reports of CT, MRI, nuclear medicine and ultrasonography (April 2018 to March 2019). RESULTS: Three hundred and twenty-one reports were double starred (0.52% of 62,143 reports, 1.32 reports/day), and transmission of relevant information was incomplete in 23 cases (7.17%). Causes of incomplete transmission were (1) reports not being opened (n = 17), (2) relevant information on reports being overlooked (n = 5), and (3) the wrong report being opened (n = 1). Sixty-five reports contained triple stars (0.10%, 0.27 reports/day). CONCLUSION: The proposed strategy may be effective in preventing communication errors in radiology reports with important findings requiring semi-emergency clinical action.

Early detection of progressive disease using thyroglobulin doubling-time in metastatic differentiated thyroid carcinoma treated with radioactive iodine.

OBJECTIVE: Detectable serum thyroglobulin (Tg) in patients with differentiated thyroid carcinoma (DTC) after total thyroidectomy indicates progression of the disease. Thyroglobulin doubling-time (TgDT) is a powerful prognostic predictor in patients with DTC. We aimed to evaluate the value of the dynamic TgDT for early detection of progressive disease (PD) in the patients of metastatic DTC with I radioactive iodine (RAI) therapy. METHODS: We retrospectively evaluated 21 patients undergoing RAI therapy with metastatic DTC. Patients were defined as PD or non-PD according to Response Evaluation Criteria in Solid Tumors 1.1. TgDT was calculated by Excel-based software using Tg values measured during routine follow-up. Whole data (WDT), initial four data (IDT) and recent four data (RDT) of TgDT after total thyroidectomy were calculated and compared. RESULTS: Among the 21 patients (10 men; median age, 62 years old; range, 33-80), 11 patients were classified into PD and 10 were into non-PD. The initial Tg after total thyroidectomy showed a significant difference between PD and non-PD patients (P = 0.013). Short WDT, IDT and RDT (less than one year) showed a high correlation with PD (P < 0.05). RDT showed the highest predictive value for PD (P < 0.001). All the 11 PD patients showed RDT less than one year before PD (median follow-up, 157 days; range, 88-252). CONCLUSIONS: RDT is a powerful PD predictor in patients with metastatic DTC. Dynamic monitoring of RDT should be applied for the early detection of PD in clinic.

Prognostic significance of semi-quantitative FDG-PET parameters in stage I non-small cell lung cancer treated with carbon-ion radiotherapy.

PURPOSE: Prognostic significance of volumetric 18F-fluorodeoxyglucose (FDG) positron emission tomography/computer tomography (PET/CT) parameters in carbon-ion radiotherapy (C-ion RT) treated stage I non-small cell lung cancer, and need of histology-wise separate cut-off values for risk stratification were assessed. METHODS: Thirty-nine patients (29 men and 10 women, 71.9 ± 8.3 years) who underwent FDG PET/CT examinations before C-ion RT were retrospectively evaluated. FDG-PET parameters: standardized uptake values (SUVmax, SUVpeak, and SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), and clinicopathological variables were assessed for prognosis using Cox proportional hazards regression analysis. Mann-Whitney test compared medians of significant parameters between adenocarcinoma (AC) and squamous cell carcinoma (SCC), and Kaplan-Meier curves were plotted for median-based low- and high-risk groups. RESULTS: Median follow-up period was 44.8 months. 1/2/3-year overall survival (OS), progression-free survival (PFS) and local control (LC) rates were 94.9/84.3/70.8, 82.1/69.2/58.4 and 97.3/85.7/82.3%. Multivariate analysis revealed age (hazard ratio, HR: 1.09; 95% confidence interval, CI: 1.0-1.19, p < 0.05) and MTV (HR 4.83, 95% CI 1.21-19.27, p < 0.03) predicted OS, and only MTV predicted PFS (HR 5.3, CI 1.32-21.35, p < 0.02) independently. Compared with AC, SCC had higher MTV (median, 6.625cm3 vs 0.2 cm3, p < 0.01). Single MTV cut-off based on overall cohort was insignificant in SCC for PFS (p > 0.02); separate cut-offs of MTV, 0.2 cm3 for AC (p < 0.03) and 6.625 cm3 for SCC (p < 0.05) were relevant. CONCLUSION: Among all FDG PET/CT parameters, only MTV beared prognostic ability for stage I NSCLC treated with C-ion RT, and its histological variation may need consideration for risk-adapted therapeutic management.

18F-FDG and 18F-FAMT PET-derived metabolic parameters predict outcome of oral squamous cell carcinoma.

OBJECTIVES: L-3-[18F]-Fluoro-α-methyl tyrosine (FAMT), an amino acid positron emission tomography (PET) tracer, complements [18F]-fluorodeoxyglucose (FDG) in the diagnosis of malignancies. We compared the predictive ability of FAMT PET versus FDG PET regarding metastatic oral squamous cell carcinoma (OSCC) outcomes for distant metastasis, including lymph node metastasis, and identified the relevant metabolic parameters for each. METHODS: We enrolled 160 patients with OSCC who underwent PET/computed tomography using FDG and FAMT before treatment. Outcomes were assessed using clinicopathological characteristics such as the standardized uptake value (SUVmax, SUVpeak), metabolic tumor volume (MTV), and total lesion glycolysis or total lesion retention. Univariate and multivariate Cox proportional hazards models were used to identify the independent predictors of disease-free survival (DFS) and overall survival (OS) during an average follow-up time of 1401.7 and 1646.0 days, respectively. Areas under the receiver operating characteristic curves were analyzed for the accuracy and predictive value of imaging parameters. RESULTS: Clinical parameters (excluding age) and PET metabolic parameters were significantly associated with OS. Multivariate analysis showed that an infiltrative growth pattern [p = 0.034, hazard ratio (HR) = 2.30], and the FDG-measured SUVpeak (p = 0.045, HR = 2.45) were independent risk factors for DFS and that lymph node metastasis (p = 0.03, HR = 2.57) and the FAMT-measured MTV (p = 0.004, HR = 3.65) were independent risk factors for OS. CONCLUSIONS: In patients with OSCC, FDG PET predicted DFS, whereas FAMT predicted OS. The two PET tracers, combined with clinical parameters, provide complementary, outcome-related diagnostic information in OSCC.

Clinical value of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography for interstitial lung disease and myositis in patients with dermatomyositis.

18 F-Fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) is usually used to screen malignancy in patients with dermatomyositis (DM). Additionally, it is well known that FDG-PET/CT provides valuable information for evaluating the activity of several inflammatory diseases, such as sarcoidosis, atherosclerosis, inflammatory bowel disease and rheumatoid arthritis. Therefore, the objective of this study was to evaluate the clinical usefulness of FDG-PET/CT for the detection of inflammatory lesions and disease activity of both myopathy and interstitial lung disease (ILD) in DM patients. We measured the maximum standardized uptake value (SUVmax) in the muscles and lungs in 22 DM patients, and compared with magnetic resonance imaging (MRI) and high-resolution computed tomography (HRCT) findings in the same muscle and lung regions as well as with clinical findings. We found that the location of increased FDG uptake was nearly consistent with the region of ILD and myositis detected by HRCT or MRI, respectively. There was a significant positive correlation between lung HRCT score and SUVmax in each lung. Serum Krebs von den Lungen-6 levels also revealed significant positive correlation with total SUVmax of right and left lungs. Regarding FDG-PET/CT and myopathy, total SUVmax in the muscles was significantly correlated with serum cytokeratin levels. Our results suggest that FDG uptake (SUVmax) might be useful for not only the detection of malignant tumors, but also the evaluation of the location and activity of ILD and myositis in DM patients.

Uterine Artery Embolization Combined with Dilation and Curettage for the Treatment of Cesarean Scar Pregnancy: Efficacy and Future Fertility.

PURPOSE: To investigate the efficacy and safety of uterine artery embolization (UAE) followed by dilation and curettage (D&C) as a treatment for cesarean scar pregnancy (CSP) and to assess pregnancy outcomes after the treatment. MATERIALS AND METHODS: We retrospectively analyzed 33 CSP patients treated with UAE followed by D&C. The serum level of beta human chorionic gonadotropin (ß-hCG) normalization, hospitalization, menstruation, and successful pregnancy after treatment was assessed as clinical and pregnancy outcomes. RESULTS: A total of 33 patients were initially treated without severe complications. However, four patients required additional systemic chemotherapy. ß-hCG normalization took 35.5 ± 14.9 days (range 13-79), and the hospitalization was 6.5 ± 2.5 days (2-15). All patients resumed normal menstruation after 36 ± 19.2 days (12-86). Of 16 of 33 patients who desired pregnancy after the treatment, seven patients (43.8%) had uneventful parturition. CONCLUSIONS: UAE combined with D&C was efficient and safe for CSP management. This minimally invasive procedure may be considered as one of the treatment options which enable preservation of fertility after treatment.

Evaluation of bone scan index change over time on automated calculation in bone scintigraphy.

OBJECTIVE: Bone scintigraphy (bone scan) is useful in detecting metastatic bone lesions through visual assessment of hot spots. A semi-quantitative analysis method that evaluates bone scan images has been eagerly anticipated. BONENAVI is software that enables automatic assessment of bone scan index (BSI). BSI is useful for stratifying cancer patients and monitoring their therapeutic response. The purpose of this study was to evaluate the BONENAVI reading in determining BSI and hot spots at different time intervals after radioisotope injection. METHODS: We evaluated 32 patients, including 22 males and 10 females. Ten patients had breast cancer, 20 patients had prostate cancer, and 2 had malignant pheochromocytoma. Patients were injected with 740 MBq of (99m)Tc-methylene diphosphonate and bone scintigraphy was performed at 2, 4, and 6 h after injection on each patient. The BSI and the number of hot spots were obtained from BONENAVI software. Bone scan images were also visually assessed to exclude false positives due to artifacts. Analyses were performed in all lesions, selected true lesions, segment based and cancer type based. Non-parametric statistical analyses for pairwise multiple group comparison were performed using Friedman test followed with post hoc analysis. RESULTS: The BSIs and the number of hot spots were significantly increased with time, with significant differences between each of time points (P < 0.001). Analysis of regional BSI (rBSI) and hot spot number changes of selected 15 true lesions also showed similar increase (P < 0.001). In general, the pelvic segment was the most prone to rBSI changes and the chest segment was the most prone to hot spot number changes. Visual assessment showed that BONENAVI diagnosed some typical artifacts as metastases (hot spots). CONCLUSION: BONENAVI reading of BSIs and hot spot numbers was highly affected by acquisition time. In serial or follow-up examinations (in particular, for monitoring therapeutic efficacy), acquisition time should be fixed for each patient. Cautious interpretation should be made on segments with high physiological uptake. BONENAVI reading was prone to misinterpretation of artifacts. Visual assessment is necessary to rule out this possibility.

Air embolism detected during computed tomography fluoroscopically guided transthoracic needle biopsy.

Air embolism is a rare but potentially fatal complication of percutaneous needle biopsy of the lung. We report a case of cerebral air embolism which occurred during computed tomography (CT)-guided needle biopsy. Air entering the aorta is depicted on CT-fluoroscopy images of the procedure.

Perfusion CT of breast carcinoma: arterial perfusion of nonscirrhous carcinoma was higher than that of scirrhous carcinoma.

RATIONALE AND OBJECTIVES: Our goals were to apply perfusion CT technique to breast tumor and to evaluate the correlation between arterial perfusion value and other tumor characteristics. MATERIALS AND METHODS: Thirty-one female patients with primary breast tumors were included in this study. A single-slice dynamic CT was performed after an intravenous bolus injection of contrast material (40 ml; 370 mg I/ml) at 8 ml/sec. The parameters were calculated on a pixel-by-pixel basis by using maximum slope method, and quantitative maps of arterial perfusion were created. Statistical correlation between tumor size, patient age, and perfusion were assessed. Differences in perfusion between scirrhous and nonscirrhous carcinoma were also assessed. RESULTS: Perfusion CT images were successfully created for 24 patients (mean age, 55.9 years old; range, 36-85 years). In five patients, dynamic CT was not performed due to lack of visualization of the breast tumor on unenhanced CT. In two patients, reliable perfusion CT image could not be created because of motion artifact. The mean perfusion for 24 tumors was 33.1 +/- 16.9 ml/min/100 ml (mean +/- SD; range, 14-78), and the tumor perfusion did not correlate with patient's age or tumor size (21.0 +/- 10.2 mm; range, 10-45 mm). The mean perfusion of nonscirrhous carcinoma (45.8 ml/min/100 ml; n = 11) was higher than that of scirrhous carcinoma (22.7 ml/min/100 ml; n = 11; P < .001). CONCLUSION: Determination of the perfusion of breast carcinoma is feasible by dynamic CT and can be performed during a routine CT study without much supplementary burden on the patient. There are differences in blood flow between scirrhous and nonscirrhous breast carcinoma, and further research is needed to determine the impact of this finding.

Inverse correlation between tumor perfusion and glucose uptake in human head and neck tumors.

RATIONALE AND OBJECTIVES: We sought to determine the relationship between tumor blood flow and glucose uptake in head and neck tumors using perfusion computed tomography (PCT) and fluorine-18-fluorodeoxyglucose (FDG) positron emission tomography (PET). MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained for this study. Sixteen patients (mean age, 67 years; age range, 36-89 years) who had known or suspected head and neck tumors (15 malignant tumors and one schwannoma) underwent PCT and FDG PET examinations. Tumor area was measured on conventional CT images. The PCT data were postprocessed using maximum slope method analysis, and standardized uptake value (SUV) was measured on FDG PET. RESULTS: Mean arterial perfusion of the tumors was 61.56 mL/min/100 mL (range 22.17-102.7 mL/min/100 mL), and mean FDG SUV was 7.48 (range 2.74-17.1). A significant negative correlation between arterial perfusion and FDG SUV was found for malignant tumors (r = -0.538, P = .04, n = 15). CONCLUSION: There was an inverse relationship between arterial perfusion and glucose uptake of head and neck malignant tumors, suggesting that the malignant tumors may depend on anaerobic glycolysis.