A stepwise strategy integrating dynamic stress CT myocardial perfusion and deep learning-based FFRCT in the work-up of stable coronary artery disease.

OBJECTIVES: To validate a novel stepwise strategy in which computed tomography-derived fractional flow reserve (FFRCT) is restricted to intermediate stenosis on coronary computed tomography angiography (CCTA) and computed tomography myocardial perfusion imaging (CT-MPI) was reserved for vessels with gray zone FFRCT values. MATERIALS AND METHODS: This retrospective study included 87 consecutive patients (age, 58 ± 10 years; 70% male) who underwent CCTA, dynamic CT-MPI, interventional coronary angiography (ICA), and fractional flow reserve (FFR) for suspected or known coronary artery disease. FFRCT was computed using a deep learning-based platform. Three stepwise strategies (CCTA + FFRCT + CT-MPI, CCTA + FFRCT, CCTA + CT-MPI) were constructed and their diagnostic performance was evaluated using ICA/FFR as the reference standard. The proportions of vessels requiring further ICA/FFR measurement based on different strategies were noted. Furthermore, the net reclassification index (NRI) was calculated to ascertain the superior model. RESULTS: The CCTA + FFRCT + CT-MPI strategy yielded the lowest proportion of vessels requiring additional ICA/FFR measurement when compared to the CCTA + FFRCT and CCTA + CT-MPI strategies (12%, 22%, and 24%). The CCTA + FFRCT + CT-MPI strategy exhibited the highest accuracy for ruling-out (91%, 84%, and 85%) and ruling-in (90%, 85%, and 85%) functionally significant lesions. All strategies exhibited comparable sensitivity for ruling-out functionally significant lesions and specificity for ruling-in functionally significant lesions (p > 0.05). The NRI indicated that the CCTA + FFRCT + CT-MPI strategy outperformed the CCTA + FFRCT strategy (NRI = 0.238, p < 0.001) and the CCTA + CT-MPI strategy (NRI = 0.233%, p < 0.001). CONCLUSIONS: The CCTA + FFRCT + CT-MPI stepwise strategy was superior to the CCTA + FFRCT strategy and CCTA+ CT-MPI strategy by minimizing unnecessary invasive diagnostic catheterization without compromising the agreement rate with ICA/FFR. CLINICAL RELEVANCE STATEMENT: Our novel stepwise strategy facilitates greater confidence and accuracy when clinicians need to decide on interventional coronary angiography referral or deferral, reducing the burden of invasive investigations on patients. KEY POINTS: • A stepwise CCTA + FFRCT + CT-MPI strategy holds promise as a viable method to reduce the need for invasive diagnostic catheterization, while maintaining a high level of agreement with ICA/FFR. • The CCTA + FFRCT + CT-MPI strategy performed better than the CCTA + FFRCT and CCTA + CT-MPI strategies. • A stepwise CCTA + FFRCT + CT-MPI strategy allows to minimize unnecessary invasive diagnostic catheterization and helps clinicians to referral or deferral for ICA/FFR with more confidence.

Diagnostic Performance of CT FFR With a New Parameter Optimized Computational Fluid Dynamics Algorithm From the CT-FFR-CHINA Trial: Characteristic Analysis of Gray Zone Lesions and Misdiagnosed Lesions.

To assess the diagnostic performance of fractional flow reserve (FFR) derived from coronary computed tomography angiography (CTA) (CT-FFR) obtained by a new computational fluid dynamics (CFD) algorithm to detect ischemia, using FFR as a reference, and analyze the characteristics of "gray zone" and misdiagnosed lesions. This prospective multicenter clinical trial (NCT03692936, https://clinicaltrials.gov/) analyzed 317 patients with coronary stenosis between 30 and 90% in 366 vessels from five centers undergoing CTA and FFR between November 2018 and March 2020. CT-FFR were obtained from a CFD algorithm (Heartcentury Co., Ltd., Beijing, China). Diagnostic performance of CT-FFR and CTA in detecting ischemia was assessed. Coronary atherosclerosis characteristics of gray zone and misdiagnosed lesions were analyzed. Per-vessel sensitivity, specificity and accuracy for CT-FFR and CTA were 89.9, 87.8, 88.8% and 89.3, 35.5, 60.4%, respectively. Accuracy of CT-FFR was 80.0% in gray zone lesions. In gray zone lesions, lumen area and diameter were significantly larger than lesions with FFR < 0.76 (both p < 0.001), lesion length, non-calcified and calcified plaque volume were all significantly higher than non-ischemic lesions (all p < 0.05). In gray zone lesions, Agatston score (OR = 1.009, p = 0.044) was the risk factor of false negative results of CT-FFR. In non-ischemia lesions, coronary stenosis >50% (OR = 2.684, p = 0.03) was the risk factor of false positive results. Lumen area (OR = 0.567, p = 0.02) and diameter (OR = 0.296, p = 0.03) had a significant negative effect on the risk of false positive results of CT-FFR. In conclusion, CT-FFR based on the new parameter-optimized CFD model provides better diagnostic performance for lesion-specific ischemia than CTA. For gray zone lesions, stenosis degree was less than those with FFR < 0.76, and plaque load was heavier than non-ischemic lesions.

Knowledge of Hyperemic Myocardial Blood Flow in Healthy Subjects Helps Identify Myocardial Ischemia in Patients With Coronary Artery Disease.

BACKGROUNDS: Dynamic CT myocardial perfusion imaging (CT-MPI) allows absolute quantification of myocardial blood flow (MBF). Although appealing, CT-MPI has not yet been widely applied in clinical practice, partly due to our relatively limited knowledge of CT-MPI. Knowledge of distribution and variability of MBF in healthy subjects helps in recognition of physiological and pathological states of coronary artery disease (CAD). OBJECTIVES: To describe the distribution and normal range of hyperemic MBF in healthy subjects obtained by dynamic CT-MPI and validate whether it can accurately identify functional myocardial ischemia when the cut-off value of hyperemia MBF is set to the lower limit of the normal range. MATERIALS AND METHODS: Fifty-one healthy volunteers (age, 38 ± 12 years; 15 men) were prospectively recruited. Eighty patients (age, 58 ± 10 years; 55 men) with suspected or known CAD who underwent interventional coronary angiography (ICA) examinations were retrospectively recruited. Comprehensive CCTA + dynamic CT-MPI protocol was performed by the third - generation dual-source CT scanner. Invasive fractional flow reserve (FFR) measurements were performed in vessels with 30-90% diameter reduction. ICA/FFR was used as the reference standard for diagnosing functional ischemia. The normal range for the hyperemic MBF were defined as the mean ± 1.96 SD. The cut-off value of hyperemic MBF was set to the lower limit of the normal range. RESULTS: The global hyperemic MBF were 164 ± 24 ml/100 ml/min and 123 ± 26 ml/100 ml/min for healthy participants and patients. The normal range of the hyperemic MBF was 116-211 ml/100 ml/min. Of vessels with an ICA/FFR result (n = 198), 67 (34%) were functionally significant. In the per-vessel analysis, an MBF cutoff value of <116 ml/100 ml/min can identify myocardial ischemia with a diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 85.9% (170/198), 91.0% (61/67), 83.2 % (109/131), 73.5% (61/83), and 94.8% (109/115). CT-MPI showed good consistency with ICA/FFR in diagnosing functional ischemia, with a Cohen's kappa statistic of 0.7016 (95%CI, 0.6009 - 0.8023). CONCLUSION: Recognizing hyperemic MBF in healthy subjects helps better understand myocardial ischemia in CAD patients.

Clinical and CT features of ovarian torsion in infants, children and adolescents.

OBJECTIVE: To investigate the clinical features and computed tomography (CT) findings of pediatric ovarian torsion. METHODS: A retrospective analysis of the clinical and CT data of 61 newborns, infants, children, and adolescents with ovarian torsion confirmed by histopathology was performed. RESULTS: Clinical features included abdominal mass, abdominal pain, nausea and vomiting, and fever. The tumor marker α-fetoprotein was increased in five cases. Ovarian enlargement was found in 26 cases, and follicles were detected in the peripheral region of the ovary in 21 cases. Twenty-one cases presented as solid mixed-density masses on CT images. A total of 30 cases of ovarian torsion were associated with a benign ovarian mass. Among 27 cases of cystic or predominantly cystic masses, the mass had a thickened wall in 26 cases and showed an uneven density in 23 cases. Among all 61 patients, a torsed pedicle was detected in 47 cases. A torsed ovary or mass exhibited mild contrast enhancement in seven cases. Uterine deviation toward the involved side, blurred fat space around lesions, and pelvic free fluid were also found. CONCLUSION: Pediatric ovarian torsion presents a relatively characteristic CT appearance. Correct diagnosis can be established based on clinical and imaging features.

Computed Tomography and Clinical Analysis of Ovarian Mucinous Tumors in Adolescent Patients.

STUDY OBJECTIVE: To investigate the clinical and computed tomography features of ovarian mucinous tumors in children and adolescents. DESIGN, SETTING, AND PARTICIPANTS: A retrospective analysis of clinical and preoperative computed tomography (CT) data was performed in 59 patients who were 20 years or younger with ovarian mucinous tumors confirmed by histopathology. Patients' age, medical history, symptoms, tumor marker levels, and CT imaging findings were recorded. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Identification of the clinical and CT features of ovarian mucinous tumors in pediatric and adolescent patients. RESULTS: There were 41 mucinous cystadenomas in 39 cases, 12 borderline mucinous cystadenomas in 11 cases, and 9 mucinous cystadenocarcinomas in 9 patients. A total of 55 tumors were multilocular (55/62, 88.7%), including fewer than 10 loculations in 23 tumors, 10-20 loculations in 17 tumors, and over 20 loculations in 15 tumors. Eleven borderline mucinous cystadenomas were multilocular (11/12, 91.7%), with over 10 loculations in 7 tumors (7/12, 58.3%). Twelve tumors appeared as multilocular cystic-solid (12/62, 19.4%), and a case of mucinous cystadenocarcinoma was predominantly solid (1/62, 1.6%). Seventeen tumors showed honeycomb sign and stained glass appearance. Six mural nodules, with sizes ranging from 1.1 to 3.5 cm (average: 2.8 cm), were found in borderline mucinous cystadenoma and mucinous cystadenocarcinoma. CONCLUSIONS: The CT findings of ovarian mucinous tumors in children are characteristic. The preoperative CT is helpful in making differential diagnoses.

CT-FFR vs a model of combined plaque characteristics for identifying ischemia: Results from CT-FFR CHINA trial.

OBJECTIVES: To evaluate the diagnostic performance of fractional flow reserve (FFR) derived from coronary computed tomography angiography (CCTA; CT-FFR) and combined plaque characteristics for ischemia in different CCTA stenosis levels. METHODS: This clinical trial analyzed 317 patients with 30 %-90 % coronary stenosis in 366 vessels from 5 centers undergoing CCTA and invasive FFR. 366 vessels were assigned into < 50 % (nonobstructive) and ≥ 50 % (obstructive) stenosis groups. Lesion length (LL), plaque burden (PB), diameter stenosis (DS), volume ratio of plaque subcomponents < 30 HU (VR < 30HU), and high-risk features were analyzed. Logistic regression models were used to identify plaque characteristic predictors for lesion-specific ischemia in different stenosis grades. The area under receiver operating characteristics curve (AUC) of integrated plaque characteristics and CT-FFR were calculated and compared. RESULTS: In < 50 % stenosis lesions, PB (OR: 1.296, p = 0.002), LL (OR:1.075, p = 0.020), and DS (OR:1.085, p = 0.031) were independent predictors of ischemia. In ≥ 50 % stenosis lesions, VR < 30HU (OR:1.031, p = 0.005) and DS (OR: 1.020, p = 0.044) were independent predictors for ischemia. AUC of plaque characteristic (VR < 30HU plus DS) for ischemia was 0.67 (95 % CI: 0.61-0.72) in ≥ 50 % stenosis level, which was significantly lower than CT-FFR (AUC=0.90; 95 % CI: 0.86-0.93) (p < 0.001). For lesions causing < 50 % stenosis, AUC of combined plaque model (VR < 30HU plus DS) was 0.88 (95 % CI: 0.80-0.95), equivalent to AUC of CT-FFR (AUC = 0.88; 95 % CI: 0.80-0.96; p = 0.957). CONCLUSION: CT-FFR is a powerful functional assessment tool for both obstructive and nonobstructive diseases. However, for nonobstructive CAD confirmed by CCTA, a model of a combination of plaque characteristics could be a valuable alternative to CT-FFR.

Effect of Coronary Calcification Severity on Measurements and Diagnostic Performance of CT-FFR With Computational Fluid Dynamics: Results From CT-FFR CHINA Trial.

Aims: To explore the effect of coronary calcification severity on the measurements and diagnostic performance of computed tomography-derived fractional flow reserve (FFR; CT-FFR). Methods: This study included 305 patients (348 target vessels) with evaluable coronary calcification (CAC) scores from CT-FFR CHINA clinical trial. The enrolled patients all received coronary CT angiography (CCTA), CT-FFR, and invasive FFR examinations within 7 days. On both per-patient and per-vessel levels, the measured values, accuracy, and diagnostic performance of CT-FFR in identifying hemodynamically significant lesions were analyzed in all CAC score groups (CAC = 0, > 0 to <100, ≥ 100 to <400, and ≥ 400), with FFR as reference standard. Results: In total, the sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under receiver operating characteristics curve (AUC) of CT-FFR were 85.8, 88.7, 86.9, 87.8, 87.1%, 0.90 on a per-patient level and 88.3, 89.3, 89.5, 88.2, 88.9%, 0.88 on a per-vessel level, respectively. Absolute difference of CT-FFR and FFR values tended to elevate with increased CAC scores (CAC = 0: 0.09 ± 0.10; CAC > 0 to <100: 0.06 ± 0.06; CAC ≥ 100 to <400: 0.09 ± 0.10; CAC ≥ 400: 0.11 ± 0.13; p = 0.246). However, no statistically significant difference was found in patient-based and vessel-based diagnostic performance of CT-FFR among all CAC score groups. Conclusion: This prospective multicenter trial supported CT-FFR as a viable tool in assessing coronary calcified lesions. Although large deviation of CT-FFR has a tendency to correlate with severe calcification, coronary calcification has no significant influence on CT-FFR diagnostic performance using the widely-recognized cut-off value of 0.8.

Relationship between Upper Extremity Lymphatic Drainage and Sentinel Lymph Nodes in Patients with Breast Cancer.

PURPOSE: The purpose of this study was to identify the relationship between upper extremity lymphatics and sentinel lymph nodes (SLNs) in breast cancer patients. METHODS: Forty-four patients who underwent axillary reverse mapping (ARM) during axillary lymph node dissection (ALND) with SNL biopsy (SLNB) between February 2017 and October 2017 were investigated. ARM was performed using indocyanine green (ICG) to locate the upper extremity lymphatics; methylene blue dye was injected intradermally for SLN mapping. RESULTS: ARM nodes were found in the ALND fields of all examined patients. The rate of identification of upper extremity lymphatics within the SLNB field was 65.9% (29 of 44). The ARM nodes were involved in metastases arising from primary breast tumors in 7 of the patients (15.9%), while no metastases were detected in pathologic axillary lymph node-negative patients. Lymphatics from the upper extremity drained into the SLNs in 5 of the 44 patients (11.4%); their ARM-detected nodes were found to be in close proximity to the SLNs. CONCLUSIONS: The ARM nodes and SLNs are closely related and share lymphatic drainage routes. The ARM procedure using fluorescence imaging is both feasible and, in patients who are SLN negative, oncologically safe. ARM using ICG is therefore effective for identifying and preserving upper extremity lymphatics, and SLNB combined with ARM appears to be a promising surgical refinement for preventing upper extremity lymphoedema. CLINICAL TRIAL REGISTRATION: This trial is registered with ClinicalTrial.gov: NCT02651142.

Resectable primary pleural myxoid liposarcoma with a pedicle: report of a rare case and literature review.

Primary pleural myxoid liposarcoma is a rare tumor. Here, we report a primary myxoid liposarcoma occupying the majority of the left thoracic cavity with features suggesting invasion. Computed tomography (CT) at medical check-up incidentally revealed a bulky inhomogeneous fatty mass. The tumor's large size made a prediction of its resectability by preoperative CT difficult. The patient underwent an operation, which revealed that the tumor was attached to the pleura with a thin pedicle; the tumor was resected completely. Few therapies for pleural liposarcoma other than resection are available; hence, surgery should be considered even if the tumor's size implies invasion on radiological imaging. In this case report, we discuss the imaging findings of this case with a review of the related literature.

Computed tomography findings in large vestibular aqueduct syndrome.

CONCLUSIONS: Patients with large vestibular aqueduct syndrome (LVAS) have disturbed morphogenesis of bony labyrinth. Semicircular canal anomalies are common in LVAS. OBJECTIVE: To describe the additional inner ear anomalies on CT imaging in pediatric patients with LVAS, and to investigate the lateral semicircular canal (LSCC) anomalies associated with LVAS by measurement of the LSCC bony island width. PATIENTS AND METHODS: We retrospectively reviewed the digitally stored temporal bone CT imaging obtained for 23 patients with LVAS, additional inner ear anomalies were noted, and measurements of the LSCC bony island width were made on axial CT scans on the workstation. Measurements were compared to the normative data obtained from 20 patients without sensorineural hearing loss. RESULTS: Of the 23 patients (bilateral in 22 and unilateral in 1), additional inner ear malformations were identified in 21 cases presenting either singly or in combination. A small LSCC bony island (<3 mm in diameter) appeared highly typical; vestibule and LSCC anomalies were identified in 13 cases (26 ears) based on visual inspection combined with abnormal measurements. Dehiscence of the superior and/or posterior semicircular canal was identified in 19 ears, and Mondini deformity was identified in 6 ears.

[Evaluation of maximum intensity projection in HRCT in the diagnosis of the destruction of ossicular chain in chronic otitis media].

OBJECTIVE: To observe the ossicular chain structure with maximum intensity projection (MIP) and to evaluate the diagnostic value of it in the destruction of ossicular chain in chronic otitis media (COM). METHOD: Sixty-eight patients (136 ears) were scanned with HRCT. The original data was processed with MIP reconstruction technique. The images of the ossicular chain structure in normal ears were observed, while the images in suffering ears were compared with the findings in operation. RESULT: In normal ears, the ossicular chain structure was shown clearly by MIP, which can also display three-dimensional images of the ossicular chain. In the suffering ears of chronic otitis media of cholesteatoma type, granuloma type and simple type, MIP displayed the destruction of ossicular chain in 39 ears, 5 ears and 0 ear respectively, which was observed in 39 ears, 6 ears and 0 ears respectively in operation. CONCLUSION: MIP technique in HRCT can display the ossicular chain spatial structure clearly, which is very helpful to evaluate the destruction of ossicular chain in chronic otitis media (COM) and to make accurate operation plan.