ABSTRACT
BACKGROUND: Proper staging of the mediastinum is an essential component of lung cancer evaluation. Positron emission tomography-computed tomography (PETCT) and endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) are an integral part of this process. False-positive PETCT results can occur following surgical procedures but has not been demonstrated following EBUS-TBNA. We aimed to determine whether false-positive PETCT rates increase when EBUS-TBNA is performed prior to PETCT. STUDY DESIGN AND METHODS: A retrospective review was carried out of clinical cases that underwent both PETCT and EBUS-TBNA within 30 days for the suspected malignancy. The impact of test sequence on the PETCT false-positive rate (FPR) was determined using Generalised Estimating Equation logistic regression analysis. RESULTS: A total of 675 lymph node stations were sampled and imaged on PETCT. Overall, 332 (49.2%) nodes were sampled by EBUS-TBNA before PETCT, and 343 (50.8%) afterwards, with the interval between EBUS and subsequent PETCT being a mean±sd of 11.6±6.8 days (range 1-29). The FPR on qualitative PETCT for the EBUS first group was 41 (23.2%) out of 164, and for PETCT first it was 57 (29.0%) out of 193 for a difference of 5.8% (95% CI -3.4-14.7, p=0.22). In the regression model, EBUS as the first test was associated with a lower FPR when using the clinical PETCT interpretation. INTERPRETATION: The performance of EBUS-TBNA sampling did not influence the FPR of PETCT when bronchoscopy took place in the 30 days prior to testing. Test sequence should be selected based on other clinical considerations.
ABSTRACT
OBJECTIVE: The goals of our study were to retrospectively review our experience in using Tc-white blood cell (WBC) single-photon emission computed tomography/computed tomography (SPECT/CT) imaging in the evaluation of possible arterial graft infection and to attempt to establish objective criteria for assessment. METHODS: Eleven Tc-WBC SPECT/CT studies performed for the evaluation of clinically suspected arterial graft infection were retrospectively reviewed and compared with reference outcomes. In an attempt to define objective criteria for interpretation, comparison was also made with background liver and bone marrow activity. RESULTS: When compared with reference outcomes, the subjective scan interpretations showed 6 of 11 true positives (TP), 4 of 11 true negatives (TN), and 1 of 11 false positive (FP). Using the liver as a comparator resulted in 4 of 10 TP, 5 of 10 TN, and 1 of 10 FN. Using the bone marrow as a comparator resulted in 3 of 10 TP, 5 of 10 TN, and 2 of 10 FN. In one patient neither the liver nor the bone marrow was in the field of view. CONCLUSION: These findings suggest a high accuracy for Tc-WBC SPECT/CT in assessing clinically suspected arterial graft infection. Furthermore, the liver may be the best objective comparator for standardized interpretation.
Subject(s)
Arteries/surgery , Leukocytes/diagnostic imaging , Prosthesis-Related Infections/diagnostic imaging , Technetium , Tomography, Emission-Computed, Single-Photon/methods , Tomography, X-Ray Computed/methods , Aged , Female , Humans , Image Interpretation, Computer-Assisted , Male , Middle Aged , Retrospective Studies , Sensitivity and SpecificityABSTRACT
Hepatopulmonary syndrome (HPS) is a complication of portal hypertension, defined by the presence of liver disease, abnormal pulmonary gas exchange and evidence of intrapulmonary vascular dilatations producing a right-to-left intrapulmonary shunt. Liver transplantation (LT) is the treatment of choice; however, severe hypoxemia (PaO(2) < 50 mmHg on room air) is considered a contraindication to LT. This approach disadvantages some patients, particularly young patients with no intrinsic cardio-respiratory disease. We discuss one such patient who improved with LT despite having extremely severe HPS (PaO2 < 29 mmHg).
