Incidental Findings in Radiographic Imaging for Inpatients with Acute Ischemic Stroke

Prevalence and risk factors of unruptured intracranial aneurysms in ischemic stroke patients - A global meta-analysis

Background

Unruptured intracranial aneurysms (UIAs) have an estimated global prevalence of 2.8% in the adult population; however, UIA was identified among more than 10% of ischemic stroke patients. Many epidemiological studies and reviews have pointed to the presence of UIA among patients with ischemic stroke; yet, the extent of this association is not fully known. We performed a systematic review and meta-analysis to determine the prevalence of UIA in patients admitted to hospitals with ischemic stroke and transient ischemic attack (TIA) at both global and continental levels and evaluate factors associated with UIA in this population.

Methods

We identified, in five databases, all studies describing UIA in ischemic stroke and TIA patients between January 1, 2000, and December 20, 2021. Included studies were of observational and experimental design.

Results

Our search yielded 3581 articles of which 23 were included, with a total of 25,420 patients. The pooled prevalence of UIA was 5% (95% confidence interval [CI] = 4-6%) with stratified results showing 6% (95% CI = 4-9%), 6% (95% CI = 5-7%), and 4% (95% CI = 2-5%) in North America, Asia, and Europe, respectively. Significant risk factors were large vessel occlusion (odds ratios [OR] = 1.22, 95% CI = 1.01-1.47) and hypertension (OR = 1.45, 95% CI = 1.24-1.69), while protective factors were male sex (OR = 0.60, 95% CI = 0.53-0.68) and diabetes (OR = 0.82, 95% CI = 0.72-0.95).

Conclusion

The prevalence of UIA is notably higher in ischemic stroke patients than the general population. Physicians should be aware of common risk factors in stroke and aneurysm formation for appropriate prevention.

Apical pulmonary lesions suspected of malignancy visible on neck CT angiography performed for acute stroke: Prevalence, treatment, and clinical implications - the PLEURA study

BACKGROUND

Computed tomography angiography (CTA) of the supraaortic arteries is commonly used for acute stroke workup and may reveal apical pulmonary lesions (APL).

AIM

To determine the prevalence, follow-up algorithms, and in-hospital outcomes of stroke patients with APL on CTA.

METHODS

We retrospectively included consecutive adult patients with ischemic stroke, transient ischemic attack, or intracerebral hemorrhage and available CTA at a tertiary hospital between January 2014 and May 2021. We reviewed all CTA reports for the presence of APL. APL were classified as malignancy suspicious or benign appearing based on radiological-morphological criteria. We performed regression analyses to investigate the impact of malignancy suspicious APL on different in-hospital outcome parameters.

RESULTS

Among 2715 patients, APL on CTA were found in 161 patients (5.9% [95%CI: 5.1-6.9]; 161/2715). Suspicion of malignancy was present in one third of patients with APL (36.0% [95%CI: 29.0-43.7]; 58/161), 42 of whom (72.4% [95%CI: 60.0-82.2]; 42/58) had no history of lung cancer or metastases. When performed, further investigations confirmed primary or secondary pulmonary malignancy in three-quarters (75.0% [95%CI: 50.5-89.8]; 12/16), with two patients (16.7% [95%CI: 4.7-44.8]; 2/12) receiving de novo oncologic therapy. In multivariable regression, the presence of radiologically malignancy suspicious APL was associated with higher NIHSS scores at 24 h (beta = 0.67, 95%CI: 0.28-1.06, p = 0.001) and all-cause in-hospital mortality (aOR = 3.83, 95%CI: 1.29-9.94, p = 0.01).

CONCLUSIONS

One in seventeen patients shows APL on CTA, of which one-third is malignancy suspicious. Further work-up confirmed pulmonary malignancy in a substantial number of patients triggering potentially life-saving oncologic therapy.

Incidental Thyroid Nodules Found During Acute Stroke Angiography: Prevalence, Outcomes, and Suggested Management Guidelines

Objective

In stroke patients, extensive interventions for incidental thyroid nodules can be burdensome and costly. It appears that the risk of malignancy has not been reported in angiographically detected nodules and outcomes have not yet been described in patients, receiving acute stroke work-up.

Materials and Methods

Incidental thyroid nodules were found on neck computerized tomography angiography or magnetic resonance angiography performed during inpatient stroke workup (January 2017 to September 2019). These patient cases were reviewed based on sonography reports, diagnosis, and follow-up care.

Results

Of the 13 563 patients, 192 had incidental thyroid nodules (prevalence 1.4%). Twenty-six died from comorbidities and 22 received thyroid sonography. Twelve nodules from 10 patients had sonographic characteristics for biopsy: 10 benign, 1 indeterminate, and 1 papillary thyroid cancer (risk of malignancy: 8%). The cancer patient underwent hemithyroidectomy and is disease-free. Follow-up of the remaining patients showed no worsening or suspicious nodules. The American College of Radiology (ACR) guidelines would have prevented 8 unnecessary sonograms and 1 biopsy without missing malignancy.

Conclusion

Although a small risk of malignancy was noted, 95% of patients undergoing additional diagnostic thyroid testing had clinically insignificant results. The ACR guidelines can prevent unnecessary interventions. Given the 14% mortality rate in the study cohort, it is proposed that a clinical evaluation of patients is important before undergoing further diagnostics, as comorbidities may be worse than a thyroid cancer.

Prevalence, predictors and prognosis of incidental intracranial aneurysms in patients with suspected TIA and minor stroke: a population-based study and systematic review

INTRODUCTION

Unruptured intracranial aneurysms (UIAs) are common incidental imaging findings, but there are few data in patients with transient ischaemic attack (TIA)/stroke. The frequency of UIA might be higher due to shared risk factors, but rupture risk might be reduced by intensive secondary prevention. We determined the prevalence and prognosis of UIA in patients with suspected TIA/minor stroke.

METHODS

All patients referred to the population-based Oxford Vascular Study (2011-2020) with suspected TIA/minor stroke and non-invasive angiography were included. We determined the prevalence of incidental asymptomatic UIA and the risk of subsequent subarachnoid haemorrhage (SAH) by follow-up on intensive medical treatment, with guideline-based monitoring/management. We also did a systematic review of UIA prevalence/prognosis in cohorts with TIA/stroke.

FINDINGS

Among 2013 eligible patients, 95 (4.7%) had 103 previously unknown asymptomatic UIA. Female sex (OR 2.3, 95% CI 1.5 to 3.7), smoking (2.1, 1.2 to 3.6) and hypertension (1.6, 1.0 to 2.5) were independently predictive of UIA, with a prevalence of 11.1% in those with all three risk factors. During mean follow-up of 4.5 years, only one SAH occurred: 2.3 (95% CI 0.3 to 16.6) per 1000 person-years. We identified 19 studies of UIA in TIA/stroke cohorts (n=12 781), all with either symptomatic carotid stenosis or major acute stroke. The pooled mean UIA prevalence in patients with TIA/stroke was 5.1% (95% CI 4.8 to 5.5) and the incidence of SAH was 4.6 (95% CI 1.9 to 11.0) per 1000 person-years.

INTERPRETATION

The 5% prevalence of UIA in patients with confirmed TIA/minor stroke is likely higher than that in the general population. However, the risk of SAH on intensive medical treatment and guideline-based management/monitoring is low.

Incidental findings on CT angiography of the head and neck in stroke patients. Evaluation of frequency and detection rate

OBJECTIVE

A comprehensive CT algorithm in suspected ischemic stroke consists of a native CT scan, CT perfusion imaging of the brain and a CT angiography from the aortic arch to the vertex. Besides core findings of the brain and targeted vessels, various other findings may be identified. We analyzed a large patient sample and estimated the frequency of incidental findings (IFs) and whether these findings were correctly mentioned in the radiological reports.

PATIENTS AND METHODS

In the time period between 01/16 and 02/19 the radiological database of one hospital containing 1625 patients admitted for stroke suspicion were retrospectively evaluated. In total 1175 patients with ischemic stroke CTs were included. IFs were classified according to Lumbreras et al. for their clinical relevance. The primary radiological report was used to classify, whether the finding was reported initially or not.

RESULTS

Overall, 1988 IFs were identified in 1175 patients (mean 1.7 findings per patient). The most frequent finding were thyroid incidentalomas with n = 461 (23.2 % of all findings), followed by signs of mucosal swelling and/or opacification of the nasal sinus (n = 391, 19.7 %). Regarding clinical relevance, 181 findings were of major relevance (9.1 % of all findings), 902 were of moderate relevance (45.4 %) and 905 were of minor relevance (45.5 %). Overall, 772 findings (38.8 %) were not reported and 1216 (61.2 %) were sufficiently reported by the radiologist.

CONCLUSION

The present study corroborates that incidental findings are frequent in patients undergoing ischemic stroke CT, which are about half of moderate and major relevance. About 40 % of these findings were not mentioned in the primary radiology report, including findings of high clinical relevance. The radiologist should be aware of these findings.