Direct carotid-cavernous fistula presenting with intracranial hemorrhage without ocular symptoms.

Herein, we report a unique case of nontraumatic direct carotid-cavernous fistula presenting with intracerebral hemorrhage without any ocular symptoms. A 90-year-old woman was found unconscious and vomiting due to a subcortical hemorrhage in the temporal lobe. Magnetic resonance angiography revealed a direct carotid-cavernous fistula of Barrow type A. Extensive cortical venous reflux from the superficial middle cerebral vein was observed and identified as a probable contributor to the cerebral hemorrhage. We performed successful embolization using combined transarterial and transvenous approaches. We first occluded the dangerous venous drainage via the transvenous approach, followed by selective occlusion of the direct carotid-cavernous fistula via the transarterial approach. This strategy provided that the dangerous venous drainage was completely occluded first in case complete obliteration could not be achieved with the transarterial approach.

Computational Study on the Synergic Effect of Brønsted Acid and Hydrogen-Bonding Catalysis for the Dearomatization Reaction of Phenols with Diazo Functionality.

Catalytic dearomative transformations of phenol variants via an ipso-Friedel-Crafts reaction could provide a straightforward method for the rapid assembly of functionalized spiromolecules as versatile synthetic scaffolds. We previously reported a dearomative spirocyclization reaction by merging Brønsted acid and hydrogen-bonding catalysis. However, it was unclear how the reaction proceeded and how the synergic effect was triggered. Described herein are the computational studies used to elucidate the reaction mechanism. Such calculations indicated that the applied catalysts, maleic acid and Schreiner's thiourea, work cooperatively. The synergic effect enabled the chemoselectivity to interconvert between phenol dearomatization and O-H insertion, which is a major side reaction. This investigation also revealed that not only does the Schreiner's thiourea catalyst serve as a hydrogen bonding donor, but the sulfur atom in thiourea possesses a general base function. The dual functional support of the thiourea along with maleic acid would thus realize the chemoselective prioritization of dearomatization over the O-H insertion reaction under mild conditions.

Assessing the Risk of Intracranial Aneurysm Rupture Using Morphological and Hemodynamic Biomarkers Evaluated from Magnetic Resonance Fluid Dynamics and Computational Fluid Dynamics.

PURPOSE: Evaluate in vivo hemodynamic and morphological biomarkers of intracranial aneurysms, using magnetic resonance fluid dynamics (MRFD) and MR-based patient specific computational fluid dynamics (CFD) in order to assess the risk of rupture. METHODS: Forty-eight intracranial aneurysms (10 ruptured, 38 unruptured) were scrutinized for six morphological and 10 hemodynamic biomarkers. Morphological biomarkers were calculated based on 3D time-of-flight magnetic resonance angiography (3D TOF MRA) in MRFD analysis. Hemodynamic biomarkers were assessed using both MRFD and CFD analyses. MRFD was performed using 3D TOF MRA and 3D cine phase-contrast magnetic resonance imaging (3D cine PC MRI). CFD was performed utilizing patient specific inflow-outflow boundary conditions derived from 3D cine PC MRI. Univariate analysis was carried out to identify statistically significant biomarkers for aneurysm rupture and receiver operating characteristic (ROC) analysis was performed for the significant biomarkers. Binary logistic regression was performed to identify independent predictive biomarkers. RESULTS: Morphological biomarker analysis revealed that aneurysm size [P = 0.021], volume [P = 0.035] and size ratio [P = 0.039] were statistically significantly different between the two groups. In hemodynamic biomarker analysis, MRFD results indicated that ruptured aneurysms had higher oscillatory shear index (OSI) [OSI.max, P = 0.037] and higher relative residence time (RRT) [RRT.ave, P = 0.035] compared with unruptured aneurysms. Correspondingly CFD analysis demonstrated significant differences for both average and maximum OSI [OSI.ave, P = 0.008; OSI.max, P = 0.01] and maximum RRT [RRT.max, P = 0.045]. ROC analysis revealed AUC values greater than 0.7 for all significant biomarkers. Aneurysm volume [AUC, 0.718; 95% CI, 0.491-0.946] and average OSI obtained from CFD [AUC, 0.774; 95% CI, 0.586-0.961] were retained in the respective logistic regression models. CONCLUSION: Both morphological and hemodynamic biomarkers have significant influence on intracranial aneurysm rupture. Aneurysm size, volume, size ratio, OSI and RRT could be potential biomarkers to assess aneurysm rupture risk.

High-dose-rate intracavitary brachytherapy for recurrent cervical cancer in the vaginal stump after hysterectomy.

This study aimed to evaluate the treatment outcomes of patients who received high-dose-rate intracavitary brachytherapy (HDR-BT) using Iridium-192 with or without external beam radiotherapy as definitive treatment for recurrent cervical cancer after hysterectomy. Thirty-six patients with local recurrence after hysterectomy received radiotherapy including HDR-BT from 2005 to 2013. Overall survival, local control rate, and progression-free survival were estimated retrospectively via the Kaplan-Meier method. Late adverse events were also scored using the Common Terminology Criteria for Adverse Events (version 3.0). Median follow-up time was 38 (range, 7.4-101.3) months. The 3-year estimates of overall survival, local control rate, and progression-free survival were 100.0%, 82.8%, and 76.8%, respectively. Two patients (5.6%) had grade 2 lymphedema, but no other adverse events greater than grade 2 were reported. In conclusion, HDR-BT was an effective treatment modality for patients with cervical cancer recurrence in the vaginal stump.

[Effectiveness of Prothrombin Complex Concentrate for Warfarin-related Intracranial Hemorrhage].

BACKGROUND AND PURPOSE: Warfarin-associated intracranial hemorrhage(w-ICH)usually increases and results in unfavorable outcomes. Administration of prothrombin complex concentrate(PCC)can reverse anticoagulation and correct prothrombin time-international normalized ratio(PT-INR)immediately; it is recommended by some guidelines for cases of w-ICH. We assessed the effect of PCC on blood coagulation. METHODS: We administered PCC and vitamin K to 11 patients with w-ICH who were admitted to our hospital between October 2016 and November 2017. We measured the PT-INR at baseline and immediately, 1 hour, 6 hours, and on the day after PCC administration. RESULTS: Patients' mean(range)PT-INR normalized from 1.92(1.64-3.26)to 1.08(1.03-1.29)immediately after receiving PCC. Patients' PT-INR was 1.17(1.08-1.29)1 hour after receiving PCC, 1.22(1.16-1.52)6 hours after receiving PCC, and 1.17(1.05-1.29)on the day after receiving PCC. In all the cases, no side effects emerged. Five patients had a safe operation. All the patients' modified Rankin Scale scores at discharge were stable or within a permissive limit in comparison with the symptoms on admission. CONCLUSION: In our cases, administration of PCC corrected the PT-INR immediately and contributed to a better outcome of w-ICH.

Maximal calf circumference reflects calf muscle mass measured using magnetic resonance imaging.

BACKGROUND: Calf circumference (CC) has been used as a surrogate for calf muscle mass, which facilitates venous blood return to the heart through active skeletal muscle. However, the correlation between CC and calf muscle mass has not been extensively examined. This study aimed to examine the relationship between CC and calf muscle mass considering differences in sex and physique in elderly individuals. METHODS: A total of 124 community-dwelling elderly individuals ≥60 years of age (61 men, mean [±SD] age 74.3 ± 5.7 years) were enrolled. Maximal CC was measured using a tape measure with the subject supine. The cross-sectional area of skeletal muscle tissues was measured using magnetic resonance imaging from the point of greatest calf circumference to 5 cm proximal and distal. Calf muscle mass was calculated by multiplying the area of each slice by slice thickness (5 mm). RESULTS: CC was strongly correlated with calf muscle mass in male and female subjects (male: r = 0.908, P < 0.001; female: r = 0.892, P < 0.001). Multiple regression analysis revealed that CC and body mass index (BMI) were independent associate factors of calf muscle mass. The following estimation formulae were derived: (male) calf muscle mass (cm3) = 47.82 × CC (cm)-12.50 × BMI (kg/m2) -732.80; (female) calf muscle mass (cm3) = 32.23 × CC (cm) -4.85 × BMI (kg/m2) -429.94. CONCLUSIONS: A strong correlation was found between CC and calf muscle mass according to magnetic resonance imaging. Sex differences and BMI should be considered for accurate estimation of calf muscle mass using CC.

Analysis of late adverse events and their chronological changes after radiation therapy for cervical cancer.

Several late adverse events occur after radiation therapy (RT) for cervical cancer. However, there has been little reported about their chronological changes. It is still unclear whether concurrent chemoradiotherapy (CCRT) increases late complications. We aimed to evaluate the late adverse events and their chronological changes and whether CCRT increases their incidence and severity. For this purpose, we retrospectively analyzed 157 women with histologically proven cervical cancer. We reviewed all late adverse events and compared the frequency and severity between the patients who underwent CCRT and those who underwent RT alone. We calculated the cumulative occurrence rates of late adverse events stratified by the site and severity, and determined the chronological changes. With survivors' median follow-up time of 74.3 months, late adverse events occurred in 49.0% and serious complications developed in 24.2% of all patients. There was no significant difference in the cumulative incidence rate of all late adverse events between the CCRT and RT-alone groups (p = 0.720). The incidence rate of rectal bleeding was 25.5%. Serious rectal bleeding developed in 5 patients, all within 20 months from the start of RT. Importantly, the symptoms of rectal bleeding disappeared or were relieved in most patients during follow-up. In conclusion, we evaluated the late adverse events and their chronological changes after RT for cervical cancer and showed that adding chemotherapy to RT did not affect the frequency and severity of late complications, and the symptoms of rectal bleeding were relieved over time.

Contrast enhancement efficacy of iodinated contrast media: Effect of molecular structure on contrast enhancement.

PURPOSE: To investigate the contrast enhancement in DSA images based on the X-ray absorption characteristics of iodinated contrast media. METHODS: We have derived a new formula of predicting the pixel value ratio of two different contrast media and designate it as "Contrast Enhancement Ratio (CER)". In order to evaluate the accuracy of CER, we have evaluated the relationship between CER and pixel value ratio for all combinations of eleven iodinated contrast media. The non-ionic iodinated contrast media, iopamidol, iomeprol, iopromide, ioversol, iohexol, and iodixanol, were evaluated in this study. Each contrast medium was filled in the simulated blood vessel in our constructed anthropomorphic phantom, and DSA images were obtained using an angiographic imaging system. To evaluate the contrast enhancement of the contrast medium, the mean pixel value was calculated from all pixel values in the vascular image. RESULTS: CER was indicated to agree well with the pixel value ratio of two different contrast medium solutions and showed a good accuracy. CER was also shown to have a good linear relation to the pixel value ratio when the iodine concentration was constant. This means that the molecular structure of the contrast media affects contrast enhancement efficacy. Furthermore, in evaluation of contrast enhancement of iodinated contrast media by using the weight factor (that is a key factor in CER) ratio, Iodixanol, and iopamidol, and iomeprol have the same ability of contrast enhancement in DSA images, and iohexol shows the lowest ability. CONCLUSIONS: We have derived a new formula (CER) of predicting the pixel value ratio of two different contrast medium solutions, and shown that CER agreed well with the pixel value ratio for blood vessel filled with eleven contrast media.

Sub-solid nodule detectability in seven observers of seventy-nine clinical cases: comparison between ultra-low-dose chest digital tomosynthesis with iterative reconstruction and chest radiography by receiver-operating characteristics analysis.

PURPOSE: To compare sub-solid nodules detectability (SSND) between ultra-low-dose chest digital tomosynthesis (ULD-CDT) with/without iterative reconstruction (IR) and chest radiography (CR) by using low-dose computed tomography (LDCT) as the standard of reference (SOR). MATERIALS AND METHODS: Institutional Review Board approved this study and written informed consent was obtained. In a single visit, 79 subjects underwent ULD-CDT at 120 kV and 10 mA, CR and LDCT (effective dose: 0.171, 0.117 and 3.52 mSv, respectively). Sixty-three coronal images were reconstructed using CDT with/without IR. SOR as to SSN presence was determined based on LDCT images. Seven radiologists recorded SSN presence and locations by continuously-distributed rating. Receiver-operating characteristic (ROC) analysis was used to compare SSND of ULD-CDT with/without IR and CR, in total and subgroups classified by nodular longest diameter (LD) (> or < 9 mm) and mean CT attenuation value (CTAV) (> or < -600 Hounsfield of Unit (HU)). Detection sensitivity (DS) was compared among 4 groups classified by combination of the identical thresholds: nodular LD (9 mm) and mean CTAV (-600 HU) in each of ULD-CDT with/without IR and CR with Friedman and Wilcoxon signed rank test. RESULTS: SSND for total 105 SSNs as well as larger SSNs with nodular LD of 9 mm or more at ULD-CDT with IR was higher than either that at ULD-CDT without IR or CR, as the areas under the ROC curve were 0.66 ± 0.02, 0.59 ± 0.01 and 0.52 ± 0.01, respectively (p < 0.05). DS at ULD-CDT with IR was 69.5 ± 10.8% in groups with larger (LD > 9 mm) and more-attenuated (>-600 HU) SSNs, and higher than in the other 3 groups (p < 0.05). CONCLUSION: ULD-CDT with IR demonstrated better SSND than that without IR or CR, with increased DS for larger and more-attenuated SSNs compared with the remaining ones.

Corrigendum to "Distant Supervision with Transductive Learning for Adverse Drug Reaction Identification from Electronic Medical Records".

[This corrects the article DOI: 10.1155/2017/7575280.].

Embryonal brain tumor with unknown primary lesion and massive cerebrospinal fluid dissemination: A case report.

The 2007 World Health Organization Classification of Tumors of the Central Nervous System (CNS) categorized embryonal tumors of the CNS into three classes: medulloblastoma, CNS primitive neuroectodermal tumor, and atypical teratoid/rhabdoid tumor. Due to the lack of specific histological features, it was sometimes difficult to accurately differentiate CNS embryonal tumors pathologically. Here, we report a case of a young man, who presented with headache. Gadolinium-enhanced magnetic resonance imaging demonstrated massive lesions in the cerebrospinal fluid space, which strongly suggested leptomeningeal dissemination of a brain tumor. The histology showed the tumor comprised densely packed, small cells with scant cytoplasm. Immunoreactivities were positive for synaptophysin and chromogranin A, and negative for glial fibrillary acidic protein, S-100, EMA, and CD20. Because the tumors were located in multiple sites and most of them were within the cerebrospinal fluid space, the primary lesion could not be determined. We diagnosed this case as 'CNS primitive neuroectodermal tumor' by the patient age and predominantly supratentorial distribution of the lesions. After the induction therapy, WHO published its updated classification in 2016. Considering the possibility that the diagnosis is medulloblastoma, we performed additional immunohistochemical analyses, and diagnosed Group 3 medulloblastoma because of the expression of natriuretic peptide receptor 3.

Computer-Supported Meta-reflective Learning Model via mathematical word problem learning for training metacognition.

To become a self-regulated learner, one needs to have a skill required to induce himself to comprehend their own cognition. In this paper, we provided a definition of Seed skill to become a self-regulated learner (S2SRL) as a basis terminology for developing our proposed framework, CREMA-Computer-Supported Meta-Reflective Learning Model via MWP in order to design an environment to encourage learners to use intrinsic comprehension of metacognitive questioning to acquire S2SRL in mathematical word problem (MWP) learning. To assess our proposed framework, we addressed these questions: (i) Can CREMA really support learner to gain S2SRL and (ii) How does it work in a practical environment? To answer these two questions, three classes of low performance students of grade 9 (total 101 students) were assigned into three different learning groups: (i) a group of students who learnt MWP with our proposed method by implementing CREMA, (ii) a group of students who learnt MWP in traditional method combining MetaQ-metacognitive questions and motivational statements, and (iii) a class of students who learnt MWP in traditional method. The result from our investigation showed that MetaQ played an important role in CREMA, while integrating computer and technology enhanced students' learning sense and empowered methodology to facilitate learning objects in the implementation of CREMA to effectively support students to gain S2SRL in MWP learning.

Development of a support system for measurement and analysis of thinking processes based on a metacognitive interpretation framework: a case study of dissolution of belief conflict thinking processes.

The ability for metacognitive thought, or "thinking about thinking," is recognized as an increasingly important skill for the future enrichment of social life. However, this skill is difficult to teach because it involves implicit cognitive activities that cannot be perceived by an outside observer. In this study, we propose an interpretation framework of metacognition as one approach to considering metacognitive thinking processes. This framework serves as the design principles for developing a system that makes it possible to provide metacognitive interpretations of gaze behaviors and thought operation actions and provides a common basis for sharing and comparing knowledge from analysis results. In this study, for an example of framework-based system development, we construct a thinking externalization application and thinking analysis support system with a thinking task of dissolving belief conflict as the theme. We also demonstrate an example of the analysis of thinking about belief conflict, as derived from lower-level and higher-level thinking interpretation rules. From the example results of the defined interpretation rules, we found that the desired behavior occurred, demonstrating the postulated possibility of capturing the thought process. By realizing a series of phases on the framework proposed in this paper, it contributes to the feasibility of grasping the metacognition process and accumulating knowledge about it.

Intractable Hiccups After Coil Embolization of Partially Thrombosed Posterior Inferior Cerebellar Artery Aneurysm.

BACKGROUND: Hiccups are defined as sudden-onset involuntary contractions of the diaphragm followed by immediate inspiration and laryngeal closure, and they are considered intractable if prolonged beyond 1 month. A reflux arc involving phrenic, vagal, and central midbrain modulation is likely responsible for hiccups. We herein report a case of intractable hiccups caused by compression of the dorsal aspect of the medulla oblongata after treatment of a partially thrombosed distal posterior inferior cerebellar artery (PICA) aneurysm. CASE DESCRIPTION: A 51-year-old man presented with severe headache and was diagnosed with subarachnoid hemorrhage. Magnetic resonance imaging and cerebral angiography showed a partially thrombosed distal PICA aneurysm associated with a fusiform aneurysm in the ipsilateral vertebral artery. Based on the limited distribution of the clot, we performed endovascular coil occlusion of the aneurysm lumen followed by parent vessel occlusion for the distal PICA aneurysm. After the procedure, the patient presented with hiccups that could not be controlled by any medications. Magnetic resonance imaging showed an area of hyperintensity at the bilateral dorsal part of the medulla adjacent to the embolized aneurysm. The hiccups spontaneously disappeared 1 month after the procedure, and the abnormal signal findings also disappeared within the same period. The hiccups did not recur for 30 months postoperatively. CONCLUSIONS: In this case, the precise location of the culprit lesion causing the patient's hiccups was the dorsal medulla oblongata. Clinicians should be aware of the possibility of structural or functional disorders of the reflux arc in patients with intractable hiccups.

Distant Supervision with Transductive Learning for Adverse Drug Reaction Identification from Electronic Medical Records.

Information extraction and knowledge discovery regarding adverse drug reaction (ADR) from large-scale clinical texts are very useful and needy processes. Two major difficulties of this task are the lack of domain experts for labeling examples and intractable processing of unstructured clinical texts. Even though most previous works have been conducted on these issues by applying semisupervised learning for the former and a word-based approach for the latter, they face with complexity in an acquisition of initial labeled data and ignorance of structured sequence of natural language. In this study, we propose automatic data labeling by distant supervision where knowledge bases are exploited to assign an entity-level relation label for each drug-event pair in texts, and then, we use patterns for characterizing ADR relation. The multiple-instance learning with expectation-maximization method is employed to estimate model parameters. The method applies transductive learning to iteratively reassign a probability of unknown drug-event pair at the training time. By investigating experiments with 50,998 discharge summaries, we evaluate our method by varying large number of parameters, that is, pattern types, pattern-weighting models, and initial and iterative weightings of relations for unlabeled data. Based on evaluations, our proposed method outperforms the word-based feature for NB-EM (iEM), MILR, and TSVM with F1 score of 11.3%, 9.3%, and 6.5% improvement, respectively.

Effect on Completion of Clinical Pathway for Improving Clinical Indicator: Cases of Hospital Stay, Mortality Rate, and Comprehensive-Volume Ratio.

Many studies have analyzed the effects of clinical pathways, but most have considered only single diseases. The purpose of the present study was to exploratively analyze electronic medical records related to the use of clinical pathways, seeking trends that could usefully benefit clinical activity. From the data warehouse of University of Miyazaki Hospital, collected from April 2014 to March 2016, we retrospectively identified 6523 patients for whom a clinical pathway was applied. Other inclusion criteria were single hospitalization, the type of medical fee was comprehensive, and data were available so that all clinical indicators could be calculated. Two types of deviation from the clinical pathway were defined: cancellation (described in the clinical pathway but not implemented) and addition (not described in the clinical pathway but nevertheless implemented). If the code of International Classification of Diseases describing the clinical pathway differed from that describing where the medical resource was mostly spent, we considered this as indicating a complication. We compared principal clinical indicators (length of hospital stay, mortality rate, and comprehensive-volume ratio) by completion rate for the clinical pathway. Regardless of whether patients had complications, completing the clinical pathway was associated with a significant reduction in length of hospital stay. This finding indicated that length of hospital stay could be shortened if all medical treatments described in the clinical pathway were implemented. Our results demonstrated that it is possible to shorten the length of hospital stay by improving clinical pathways to include medical treatment for preventing complications.

Clinical outcomes of 125I brachytherapy with and without external-beam radiation therapy for localized prostate cancer: results from 300 patients at a single institution in Japan.

The aim of this study was to determine the outcomes and adverse events for 300 men with prostate cancer treated with 125iodine (125I) brachytherapy with and without external-beam radiation therapy (EBRT) at a single institution in Japan. Between February 2005 and November 2011, 300 consecutive patients with clinically localized prostate cancer were treated with 125I brachytherapy at the Nagoya University Hospital. A total of 271 men were treated with implants with doses of 145 Gy, and 29 men were treated with implants with doses of 110 Gy combined with EBRT (40-50 Gy/20-25 fractions). The median patient age was 69 years (range, 53-83 years). The median follow-up period was 53 months (range, 5-99 months). According to the National Comprehensive Cancer Network risk classification, 132 men (44%) had low-risk, 147 men (29%) had intermediate-risk and 21 men (7%) had high-risk disease. The 5-year overall survival rate, biochemical relapse-free survival rate, and disease-specific survival rates were 93.5%, 97.3% and 98.5%, respectively. Two men (0.6%) died of prostate cancer and 10 men (3.3%) died of other causes. Seventeen men (5.6%) experienced Grade 2 rectal bleeding in all: 12 (41.4%) of 29 in brachytherapy with EBRT, and 5 (1.8%) of 271 in brachytherapy alone. The rates of Grade 2 and 3 genitourinary toxicity were 1.0% and 1.7%, respectively. Excellent local control was achieved at our hospital for localized prostate cancer with 125I brachytherapy with and without EBRT. Gastrointestinal and genitourinary toxicities were acceptable.

[Tentorial Dural Arteriovenous Fistula Successfully Treated with Transvenous Embolization Using a Double Catheterization Technique through Venous Drainage:A Case Report].

BACKGROUND: Tentorial dural arteriovenous fistulas(dAVFs)are a rare clinical entity accounting for less than 10% of all intracranial dAVFs. Because these lesions are characterized by high hemorrhagic risk, aggressive treatment should be considered. Although the number of reported cases treated with endovascular transarterial embolization(TAE)using glue has been increasing, little is known about the transvenous approach. Here, we report the case of a patient with a tentorial dAVF who was successfully treated with transvenous embolization(TVE)through venous drainage using a double catheterization technique. CASE PRESENTATION: A 68-year-old male patient who had a history of left putaminal hemorrhage treated with a craniotomy was diagnosed with a tentorial dAVF on a magnetic resonance angiogram. Because the patient refused another craniotomy for surgical interruption of the dAVF, an endovascular approach was considered. We first attempted to perform TAE with glue, but catheterization into the tortuous meningohypophyseal trunk failed. We then performed a TVE of the venous drainage near the shunt with detachable coils and achieved complete obliteration of the fistula. During coil embolization of the venous drainage, insertion of small coils near the shunt was supported by another anchor coil that was delivered using a double catheterization technique. CONCLUSIONS: The method of TVE through venous drainage using a double catheterization technique, which involved placing coils in the fragile drainage vein, was safe and effective in a case of tentorial dAVF. This technique should be considered as another option for the management of complex tentorial dAVFs.

Sub-solid Nodule Detection Performance on Reduced-dose Computed Tomography with Iterative Reduction: Comparison Between 20 mA (7 mAs) and 120 mA (42 mAs) Regarding Nodular Size and Characteristics and Association with Size-specific Dose Estimate.

RATIONALE AND OBJECTIVES: This study aimed to compare sub-solid nodule detection performances (SSNDP) on chest computed tomography (CT) with Adaptive Iterative Dose Reduction using Three Dimensional Processing (AIDR 3D) between 7 mAs (0.21 mSv) and 42 mAs (1.28 mSv) in total and in subgroups classified by nodular size, characteristics, and location, and analyze the association of SSNDP with size-specific dose estimate (SSDE). MATERIALS AND METHODS: As part of the Area-detector Computed Tomography for the Investigation of Thoracic Diseases Study, a Japanese multicenter research project, 68 subjects underwent chest CT with 120 kV, 0.35 seconds per rotation, and three tube currents: 240 mA (84 mAs), 120 mA (42 mAs), and 20 mA (7 mAs). The research committee of the study project outlined and approved our study protocols. The institutional review board of each institution approved this study. Axial 2-mm-thick CT images were reconstructed using AIDR 3D. Standard reference was determined by CT images at 84 mAs. Four radiologists recorded SSN presence by continuously distributed rating on CT at 7 mAs and 42 mAs. Receiver operating characteristic analysis was used to evaluate SSNDP at both doses in total and in subgroups classified by nodular longest diameter (LD) (≥5 mm), characteristics (pure and part-solid), and locations (ventral, intermediate, or dorsal; central or peripheral; and upper, middle, or lower). Detection sensitivity was compared among five groups of SSNs classified based on particular SSDE to nodule on CT with AIDR 3D at 7 mAs. RESULTS: Twenty-two part-solid and 86 pure SSNs were identified. For larger SSNs (LD ≥ 5 mm) as well as subgroups classified by nodular locations and part-solid nodules, SSNDP was similar in both methods (area under the receiver operating characteristics curve: 0.96 ± 0.02 in CT at 7 mAs and 0.97 ± 0.01 in CT at 42 mAs), with acceptable interobserver agreements in five locations. For larger SSNs (LD ≥ 5 mm), on CT at 42 mAs, no significant differences in detection sensitivity were found among the five groups classified by SSDE, whereas on CT with 7 mAs, four groups with SSDE of 0.65 or higher were superior in detection sensitivity to the other group, with SSDE less than 0.65 mGy. CONCLUSIONS: For SSNs with 5 mm or more in cases with normal range of body habitus, CT at 7 mAs was demonstrated to have comparable SSNDP to CT at 42 mAs regardless of nodular location and characteristics, and SSDE higher than 0.65 mGy is desirable to obtain sufficient SSNDP.

StatSensor-i point-of-care creatinine analyzer may identify patients at high-risk of contrast-induced nephropathy.

The current study assessed the accuracy of the StatSensor-i (STA) point-of-care creatinine analyzer prior to and following adjustment (offset correction) by linear regression scatter plots produced by the reference samples from patients and volunteers for detecting high risk of contrast-induced nephropathy in patients with an estimated glomerular filtration rate <45 ml/min/1.73 m2. Blood samples were obtained from 233 consecutive outpatients scheduled for contrast-enhanced CT studies. Of the 233 patients, 123 patient samples were evaluated prior to adjustment and the other 110 following adjustment. Serum creatinine levels and estimated glomerular filtration rate were measured using the analyzer and compared with the values returned by laboratory tests. Analysis was with the paired t-test, the Pearson correlation coefficient and Bland-Altman plotting. The sensitivity, specificity, positive and negative predictive values (PPV, NPV), and accuracy for detecting patients with an estimated glomerular filtration rate <45 ml/min/1.73 m2 were subsequently calculated. Mean serum creatinine levels measured with the analyzer were significantly higher than those returned by laboratory tests before (P<0.0001) and after adjustment (P<0.01). Following adjustment, the difference in serum creatinine values obtained with the STA analyzer and by laboratory methods did not exceed 0.3 mg/dl. Prior to adjustment, 9.7% of the samples were overdiagnosed as having an estimated glomerular filtration rate of <45 ml/min/1.73 m2; following adjustment, the overdiagnosis rate was 2.7%. The sensitivity, specificity, PPV, NPV and accuracy were 100, 89, 50, 100 and 90.2% before and 100, 96.3, 33.3, 100 and 96.4% after adjustment, respectively. With the adjusted point-of-care creatinine analyzer, estimated glomerular filtration rate may be reliably evaluated in the radiology suite.