Role of cardiac computed tomography in hyperacute stroke assessment.

BACKGROUND: Incorporating cardiac CT with hyperacute stroke imaging may increase the yield for cardioembolic sources. It is not clarified whether stroke severity influences on rates of intracardiac thrombus. We aimed to investigate a National Institutes of Health Stroke Scale (NIHSS) threshold below which acute cardiac CT was unnecessary. METHODS: Consecutive patients with suspected stroke who underwent multimodal brain imaging and concurrent non-gated cardiac CT with delayed timing were prospectively recruited from 1st December 2020 to 30th November 2021. We performed receiver operating characteristics analysis of the NIHSS and intracardiac thrombus on hyperacute cardiac CT. RESULTS: A total of 314 patients were assessed (median age 69 years, 61% male). Final diagnoses were ischemic stroke (n=205; 132 etiology-confirmed stroke, independent of cardiac CT and 73 cryptogenic), transient ischemic attack (TIA) (n=21) and stroke-mimic syndromes (n=88). The total yield of cardiac CT was 8 intracardiac thrombus and 1 dissection. Cardiac CT identified an intracardiac thrombus in 6 (4.5%) with etiology-confirmed stroke, 2 (2.7%) with cryptogenic stroke, and none in patients with TIA or stroke-mimic. All of those with intracardiac thrombus had NIHSS ≥4 and this was the threshold below which hyperacute cardiac CT was not justified (sensitivity 100%, specificity 38%, positive predictive value 4.0%, negative predictive value 100%). CONCLUSIONS: A cutoff NIHSS ≥4 may be useful to stratify patients for cardiac CT in the hyperacute stroke setting to optimize its diagnostic yield and reduce additional radiation exposure.

Comparison of roentgenographic manifestations of active pulmonary tuberculosis between migrant and non-migrant populations in the Hunter Region.

INTRODUCTION: Active pulmonary tuberculosis in Australia is considered more common in migrants and the immunocompromised, but little data exist on how it manifests in non-migrants. This study identified the radiographic findings of active pulmonary tuberculosis in the Hunter Region, NSW, Australia, and determined whether this manifests differently in non-migrant and migrant populations. METHODS: We retrospectively analysed 64 patients over 8 years from the Hunter Region, who had positive Mycobacterium tuberculosis cultures and contemporaneous thoracic imaging. Recorded data included age, gender, country of origin and chest radiographic findings, the latter categorised into apical fibrocavitatory disease, mixed apical fibrocavitation and consolidation, consolidation, lymphadenopathy, pleural effusions, tree-in-bud, empyema and miliary nodules. RESULTS: Sixty-four patients (men = 37, women = 27) had available thoracic imaging, of which 34 were Australian born. There was no statistically significant difference in the age between Australian-born and migrants (49.1 years (95% confidence interval, CI 42.8-55.5) vs 48.2 years (95% CI 41.1-55.3), P = 0.71). The most common radiographic manifestations were purely apical fibrocavitatory lesions (22%), mixed apical fibrocavitation and consolidation (6%) and purely consolidation (27%). Migrants were more likely to have consolidation (40%), while Australian-born individuals were more likely to have apical fibrocavitatory lesions (26%). Australian-born individuals were slightly more likely to have a normal chest radiograph (18% vs 10%). CONCLUSION: There are radiographic differences between Australian-born and migrant populations with active pulmonary tuberculosis. Migrants are more likely to present with consolidation, and Australian-born with fibrocavitatory lesions. A normal chest radiograph does not exclude active tuberculosis, and while thoracic computed tomography may be useful to detect tree-in-bud opacities, neither should not detract from commencing treatment of a positive culture for tuberculosis.

A comparison of single-photon emission CT lung scintigraphy and CT pulmonary angiography for the diagnosis of pulmonary embolism.

BACKGROUND: This study compared single-photon emission CT (SPECT) ventilation/perfusion (V/Q) scintigraphy with multislice CT pulmonary angiography (CTPA). METHODS: In a prospective, observational study, 100 patients who were >or= 50 years of age were recruited. Seventy-nine patients underwent both diagnostic 16-detector CTPA, and planar and SPECT V/Q scintigraphy. The agreement between the CTPA and the SPECT V/Q scintigraphy for the diagnosis of pulmonary embolism (PE) was calculated. The sensitivity and specificity of blinded SPECT scintigraphy reporting was calculated against a reference diagnosis made by a panel of respiratory physicians that was provided with CTPA and planar V/Q scintigraphy reports, clinical information, and 3-month follow-up data. RESULTS: The observed percentage of agreement between SPECT V/Q scintigraphy and CTPA data for the diagnosis of PE was 95%. When calculated against the respiratory physicians' reference diagnosis, SPECT V/Q scintigraphy had a sensitivity of 83% and a specificity of 98%. CONCLUSIONS: This study indicates that SPECT V/Q scintigraphy is a viable alternative to CTPA for the diagnosis of PE and has potential advantages in that it was feasible in more patients and had fewer contraindications; lower radiation dose; and, arguably, fewer nondiagnostic findings than CTPA. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Registration Number: ACTRN12609000089235.