Incidental findings of cardiac MSCT: who might benefit from scanning the entire thorax on Ca score imaging?

Prevalence of pulmonary nodules detected incidentally on noncancer-related imaging: a review

Pulmonary nodules are common incidental findings requiring surveillance. Follow-up recommendations vary depending on risk factors, size and solid or subsolid characteristics. This review aimed to evaluate the prevalence of clinically significant nodules detected on noncancer-dedicated imaging and the prevalence of part-solid and ground-glass nodules. We conducted a systematic search of literature and screened texts for eligibility. Clinically significant nodules were noncalcified nodules >4-6 mm. Prevalence estimates were calculated for all studies and risk of bias was assessed by one reviewer. Twenty-four studies were included, with a total of 30 887 participants, and 21 studies were cross-sectional in design. Twenty-two studies used computed tomography (CT) imaging with cardiac-related CT being the most frequent. Prevalence of significant nodules was highest in studies with large field of view of the chest and low size thresholds for reporting nodules. The prevalence of part-solid and ground-glass nodules was only described in two cardiac-related CT studies. The overall risk of bias was low in seven studies and moderate in 17 studies. While current literature frequently reports incidental nodules on cardiovascular-related CT, there is minimal reporting of subsolid characteristics. Unclear quantification of smoking history and heterogeneity of imaging protocol also limits reliable evaluation of nodule prevalence in nonscreening cohorts.

Prognostic value of extracardiac incidental findings on attenuation correction cardiac computed tomography

BACKGROUND

Attenuation corrected computed tomography (CTAC) is often performed to improve the specificity of single-photon emission tomography imaging. Extracardiac incidental findings are frequently observed. It is unclear whether these findings have any prognostic value.

METHODS

Consecutive patients (n = 1139) at a tertiary care center were retrospectively evaluated for incidental findings on CTAC. Clinically significant incidental findings were defined as findings warranting physician follow-up. Information regarding subsequent resource utilization was obtained by chart review. Cox proportional hazard model adjusted for demographic and clinical variables was used to evaluate association of these incidental findings with all-cause and cancer-specific mortality.

RESULTS

A total of 135 (12%) patients with incidental findings were identified, 83 of whom (68%) were newly diagnosed. Lung nodules were the most common finding, present in 92 (68%) patients. Over a median follow-up of 468 days, incidental findings were not significantly associated with increased risk of all-cause mortality (HR 1.34; 95% CI 0.77-2.33, P = 0.29) but was significantly associated with cancer-specific mortality (HR 3.21; 95% CI 1.26-8.14, P = 0.01). This association remained statistically significant when the analysis was limited to newly diagnosed incidental findings. Among patients with incidental findings, follow-up radiographic studies were conducted in 87%, and invasive procedures performed in 32%. Physician office-based follow-up of these findings occurred in 42% of patients and incidental finding-related hospitalization occurred in 14%.

CONCLUSIONS

This study shows that incidental findings are common and were associated with all-cause and cancer-specific mortality but only the later remained statistically significant after multivariable adjustment.

Incidental extracardiac findings at coronary CT: clinical and economic impact

OBJECTIVE

The purpose of this study was to evaluate the prevalence of incidental extracardiac findings on coronary CT, to determine the associated downstream resource utilization, and to estimate additional costs per patient related to the associated diagnostic workup.

MATERIALS AND METHODS

This retrospective study examined incidental extracardiac findings in 151 consecutive adults (69.5% men and 30.5% women; mean age, 54 years) undergoing coronary CT during a 7-year period. Incidental findings were recorded, and medical records were reviewed for downstream diagnostic examinations for a follow-up period of 1 year (minimum) to 7 years (maximum). Costs of further workup were estimated using 2009 Medicare average reimbursement figures.

RESULTS

There were 102 incidental extracardiac findings in 43% (65/151) of patients. Fifty-two percent (53/102) of findings were potentially clinically significant, and 81% (43/53) of these findings were newly discovered. The radiology reports made specific follow-up recommendations for 36% (19/53) of new significant findings. Only 4% (6/151) of patients actually underwent follow-up imaging or intervention for incidental findings. One patient was found to have a malignancy that was subsequently treated. The average direct costs of additional diagnostic workup were $17.42 per patient screened (95% CI, $2.84-$32.00) and $438.39 per patient with imaging follow-up (95% CI, $301.47-$575.31).

CONCLUSION

Coronary CT frequently reveals potentially significant incidental extracardiac abnormalities, yet radiologists recommend further evaluation in only one-third of cases. An even smaller fraction of cases receive further workup. The failure to follow-up abnormal incidental findings may result in missed opportunities to detect early disease, but also limits the short-term attributable costs.

Incidental non-cardiac findings of a coronary angiography with a 128-slice multi-detector CT scanner: should we only concentrate on the heart?

Objective

To evaluate the spectrum, prevalence, and significance of incidental non-cardiac findings (INCF) in patients referred for a non-invasive coronary angiography using a 128-slice multi-detector CT (MDCT).

Materials and Methods

The study subjects included 1,044 patients; 774 males (mean age, 59.9 years) and 270 females (mean age, 63 years), referred for a coronary CT angiography on a 128-slice MDCT scanner. The scans were acquired from the level of the carina to just below the diaphragm. To evaluate INCFs, images were reconstructed with a large field of view (> 300 mm) covering the entire thorax. Images were reviewed in the axial, coronal, and sagittal planes, using the mediastinal, lung, and bone windows. The INCFs were classified as severe, indeterminate, and mild, based on their clinical importance, and as thoracic or abdominal based on their locations.

Results

Incidental non-cardiac findings were detected in 56% of patients (588 of 1,044), including 435 males (mean age, 65.6 years) and 153 females (mean age, 67.9 years). A total of 729 INCFs were observed: 459 (63%) mild (58% thoracic, 43% abdominal), 96 (13%) indeterminate (95% thoracic, 5% abdominal), and 174 (24%) severe (87% thoracic, 13% abdominal). The prevalence of severe INCFs was 15%. Two severe INCFs were histologically verified as lung cancers.

Conclusion

The 128-slice MDCT coronary angiography, in addition to cardiac imaging, can provide important information on the pathology of the chest and upper abdomen. The presence of severe INCFs is not rare, especially in the thorax. Therefore, all organs in the scan should be thoroughly evaluated in daily clinical practice.