Introduction: Incidental findings on computed tomography (CT) examinations represent a significant challenge in contemporary radiology practice, with prevalence varying from 16-69% across different populations. These unexpected discoveries create complex clinical, economic, and psychological implications for patients and healthcare systems. This study aimed to determine the incidence and evaluate the clinical significance of incidental findings detected on abdominal and pelvic CT scans in hospitalized patients. Methods: A prospective cross-sectional study was conducted at Noida International Institute of Medical Sciences, Noida, Uttar Pradesh, from July 2021 to Dec 2021. Four hundred consecutive hospitalized patients aged 18 years and above who underwent abdominal and pelvic CT examinations were enrolled using systematic sampling. All scans were systematically reviewed by experienced radiologists using standardized protocols. Incidental findings were classified by organ system involvement and clinical significance categories, with comprehensive follow-up data collected to assess clinical impact and healthcare resource utilization. Results: Incidental findings were detected in 148 patients (37.0%), with 405 total abnormalities identified. Hepatobiliary system was most commonly affected (21.0%), followed by renal (19.0%) and pulmonary abnormalities (17.0%). Fourteen-point nine percent of findings were classified as highly significant requiring immediate attention, while 30.4% were moderately significant. Additional imaging was required in 45.9% of cases, with 50.0% needing specialist consultations. Patient anxiety affected 60.1% of those with findings. Age ≥60 years (p=0.042) and BMI ≥25 kg/m² (p=0.024) were significantly associated with higher detection rates. Conclusion: Incidental findings on abdominal CT scans showed substantial prevalence with significant impact on healthcare resource utilization and patient psychology, emphasizing the need for standardized reporting protocols and evidence-based management guidelines to optimize clinical benefits while minimizing adverse consequences.
Incidental findings, defined as previously unknown and clinically unsuspected abnormalities discovered during imaging studies performed for unrelated indications, have emerged as one of the most significant challenges in contemporary radiology practice (Berland et al., 2010). The exponential increase in cross-sectional imaging utilization over the past two decades, particularly computed tomography (CT) scanning, has led to an unprecedented rise in the detection of incidental abnormalities, creating complex clinical, ethical, and economic dilemmas for healthcare providers and patients alike. The prevalence of incidental findings on abdominal and pelvic CT examinations varies considerably across different studies, ranging from 16% to 69%, depending on patient population, imaging protocols, and definition criteria employed (Heller et al., 2002). The clinical significance of incidental findings spans a broad spectrum, from benign variants requiring no further intervention to potentially life-threatening malignancies demanding immediate attention and aggressive management strategies. This heterogeneous nature of incidental discoveries presents substantial challenges in developing standardized management algorithms and evidence-based guidelines for appropriate follow-up recommendations (Lumbreras et al., 2010). The increasing sensitivity of modern multidetector CT scanners, combined with improved image resolution and reconstruction techniques, has further amplified the detection rates of subtle abnormalities that might have previously remained undetected, thereby physicians, and optimize patient management strategies while minimizing unnecessary interventions. The Indian healthcare context presents unique challenges and opportunities regarding incidental findings management. The diverse patient population, varying healthcare infrastructure, and resource limitations require tailored approaches that balance diagnostic accuracy with cost-effectiveness and accessibility considerations. The increasing availability of CT imaging facilities across India has expanded diagnostic capabilities while simultaneously increasing the burden of incidental findings in both urban and rural healthcare settings (Kumar et al., 2018). Technological advancement in CT imaging, including iterative reconstruction techniques, dual-energy imaging, and artificial intelligence applications, has significantly improved image quality while reducing radiation exposure and scan times. These improvements have enhanced the detection of subtle abnormalities, potentially increasing incidental findings rates while simultaneously improving diagnostic confidence and reducing false-positive findings (Xiong et al., 2005). The integration of computer-aided detection systems and automated analysis tools holds promise for standardizing incidental findings detection and reducing inter-observer variability in interpretation. The medicolegal implications of incidental findings create additional complexity for healthcare providers, with potential liability concerns related to both failure to detect significant abnormalities and overinvestigation of benign findings. The establishment of clear documentation practices, standardized reporting protocols, and appropriate follow-up recommendations is essential for minimizing medicolegal risks while ensuring optimal patient care outcomes. Quality assurance in incidental findings management requires systematic attention to multiple components including radiologist training, standardized reporting templates, multidisciplinary communication protocols, and outcome monitoring systems. The development of institutional policies and procedures for incidental findings management ensures consistent approaches and reduces practice variation while optimizing resource utilization and patient outcomes. The aim of this study was to determine the incidence and evaluate the clinical significance of incidental findings detected on computed tomography scans of abdomen and pelvis in hospitalized patients, and to analyze their impact on patient management and healthcare resource utilization. intensifying the clinical burden associated with incidental findings. The economic implications of incidental findings extend far beyond the initial imaging costs, encompassing downstream healthcare utilization including additional imaging studies, specialist consultations, invasive procedures, and long-term surveillance programs. MacHaalany et al. (2009) demonstrated that the management of incidental findings could increase healthcare costs by 25-40% compared to targeted diagnostic imaging approaches. The cascade effect of incidental discoveries often leads to a series of additional investigations, creating substantial resource utilization and healthcare expenditure, particularly in resource-constrained healthcare systems where cost-effectiveness considerations are paramount. Patient psychological impact represents another critical dimension of incidental findings, with studies documenting significant anxiety, distress, and quality of life implications associated with the discovery of unexpected abnormalities. The uncertainty surrounding the clinical significance of many incidental findings, coupled with waiting periods for additional testing and specialist evaluation, contributes to substantial psychological burden and patient distress (Pickhardt et al., 2013). The communication of incidental findings to patients requires careful consideration of language, timing, and support mechanisms to minimize psychological harm while ensuring appropriate clinical follow-up. The classification and reporting of incidental findings have evolved significantly, with various professional organizations developing structured reporting systems and management algorithms. The American College of Radiology has established comprehensive guidelines for managing incidental findings across different organ systems, providing standardized recommendations for follow-up imaging and clinical evaluation based on lesion characteristics and patient risk factors (Berland et al., 2010). These classification systems aim to standardize reporting practices, improve communication between radiologists and referring physicians, and optimize patient management strategies while minimizing unnecessary interventions. The Indian healthcare context presents unique challenges and opportunities regarding incidental findings management. The diverse patient population, varying healthcare infrastructure, and resource limitations require tailored approaches that balance diagnostic accuracy with cost-effectiveness and accessibility considerations. The increasing availability of CT imaging facilities across India has expanded diagnostic capabilities while simultaneously increasing the burden of incidental findings in both urban and rural healthcare settings (Kumar et al., 2018). Technological advancement in CT imaging, including iterative reconstruction techniques, dual-energy imaging, and artificial intelligence applications, has significantly improved image quality while reducing radiation exposure and scan times. These improvements have enhanced the detection of subtle abnormalities, potentially increasing incidental findings rates while simultaneously improving diagnostic confidence and reducing false-positive findings (Xiong et al., 2005). The integration of computer-aided detection systems and automated analysis tools holds promise for standardizing incidental findings detection and reducing inter-observer variability in interpretation. The medicolegal implications of incidental findings create additional complexity for healthcare providers, with potential liability concerns related to both failure to detect significant abnormalities and overinvestigation of benign findings. The establishment of clear documentation practices, standardized reporting protocols, and appropriate follow-up recommendations is essential for minimizing medicolegal risks while ensuring optimal patient care outcomes. Quality assurance in incidental findings management requires systematic attention to multiple components including radiologist training, standardized reporting templates, multidisciplinary communication protocols, and outcome monitoring systems. The development of institutional policies and procedures for incidental findings management ensures consistent approaches and reduces practice variation while optimizing resource utilization and patient outcomes. The aim of this study was to determine the incidence and evaluate the clinical significance of incidental findings detected on computed tomography scans of abdomen and pelvis in hospitalized patients, and to analyze their impact on patient management and healthcare resource utilization.
Study Design
This study was conducted as a prospective observational cross-sectional study.
Study Site
The study was conducted at Noida International Institute of Medical Sciences, Noida, Uttar Pradesh, a tertiary care teaching hospital serving a large population in western Uttar Pradesh, India.
Study Duration
The study was conducted over a six-month period from July 2021 to Dec 2021.
Sampling and Sample Size
The study employed consecutive sampling methodology, enrolling all eligible hospitalized patients who underwent abdominal and pelvic CT examinations during the study period. This approach minimized selection bias and ensured representative sample composition reflecting the actual patient population undergoing CT imaging in the hospital setting. The sample size was calculated based on expected incidence rates of incidental findings derived from published literature, with assumptions indicating approximately 35% prevalence of incidental findings in abdominal CT examinations. Using a precision of ±5% for prevalence estimation, with 95% confidence level and accounting for potential incomplete data or lost to follow-up, a minimum sample size of 350 patients was calculated. The target enrollment was set at 400 patients to ensure adequate statistical power for subgroup analyses and to enable robust confidence interval estimation for various incidental findings categories and clinical significance assessments.
Inclusion and Exclusion Criteria
Inclusion criteria comprised hospitalized patients aged 18 years and above who underwent contrast-enhanced or non-contrast CT examinations of abdomen and pelvis for any clinical indication, patients with adequate image quality allowing comprehensive evaluation of abdominal and pelvic organs, those with complete clinical records and follow-up data available for analysis, and individuals providing informed consent for study participation and data utilization. Exclusion criteria included patients with known malignancies undergoing staging or surveillance examinations where findings would be considered expected rather than incidental, those with previous abdominal surgeries or interventions within six months that might confound incidental findings interpretation, patients with severe motion artifacts or technical factors limiting adequate image evaluation, individuals with incomplete imaging studies or suboptimal contrast enhancement affecting diagnostic quality, pregnant women due to radiation safety considerations, and patients unable to provide informed consent or lacking adequate follow-up information for clinical significance assessment.
Data Collection Tools and Techniques
Data collection was performed using a comprehensive structured case record form specifically designed for this study, incorporating patient demographics, clinical indications for CT examination, imaging protocol details, systematic evaluation of all abdominal and pelvic organs, detailed documentation of incidental findings using standardized classification systems, and clinical follow-up information. All CT examinations were systematically reviewed by experienced radiologists using standardized interpretation protocols, with incidental findings classified according to organ system involvement, size characteristics, imaging features, and recommended follow-up requirements based on established guidelines. Clinical correlation was performed through review of patient medical records, laboratory investigations, subsequent imaging studies, histopathological reports when available, and clinical outcomes during hospitalization and follow-up periods. The significance of incidental findings was assessed based on their impact on patient management, requirement for additional investigations, changes in treatment plans, and long-term clinical implications.
Data Management and Statistical Analysis
Data management was implemented using a secure electronic database system with built-in validation checks and quality control measures to ensure data integrity and completeness. All imaging and clinical data were systematically entered using standardized coding schemes, with double-entry verification for critical variables to minimize transcription errors. Statistical analysis was performed using SPSS version 25.0 software, with descriptive statistics including frequencies, percentages, means, and standard deviations calculated for all variables. The incidence of incidental findings was calculated with 95% confidence intervals, stratified by organ system, patient demographics, and clinical characteristics. Chi-square tests were employed to assess associations between categorical variables, while independent t-tests were used for continuous variables. Multivariate logistic regression analysis was performed to identify independent predictors of clinically significant incidental findings, controlling for potential confounding variables including age, gender, and clinical indication for imaging. Statistical significance was set at p<0.05 for all analyses, with appropriate corrections applied for multiple comparisons when necessary. used for continuous variables. Multivariate logistic regression analysis was performed to identify independent predictors of clinically significant incidental findings, controlling for potential confounding variables including age, gender, and clinical indication for imaging. Statistical significance was set at p<0.05 for all analyses, with appropriate corrections applied for multiple comparisons when necessary.
Ethical Considerations
The study protocol underwent comprehensive review and approval by the Institutional Ethics Committee of Noida International Institute of Medical Sciences, Noida, Uttar Pradesh prior to patient recruitment, ensuring compliance with ethical principles and regulatory requirements for medical research involving human subjects. Written informed consent was obtained from all study participants after detailed explanation of study objectives, procedures, potential risks and benefits, and data utilization plans.
Table 1: Demographics and Clinical Characteristics of Study Population (n=400)
Characteristics |
Frequency (n) |
Percentage (%) |
|
Age Groups |
18-40 years |
98 |
24.5 |
41-60 years |
156 |
39 |
|
61-80 years |
124 |
31 |
|
>80 years |
22 |
5.5 |
|
Gender |
Male |
218 |
54.5 |
Female |
182 |
45.5 |
|
Clinical Indication |
Abdominal pain |
142 |
35.5 |
Trauma evaluation |
78 |
19.5 |
|
Suspected malignancy |
56 |
14 |
|
Post-operative follow-up |
48 |
12 |
|
Fever of unknown origin |
42 |
10.5 |
|
Others |
34 |
8.5 |
|
CT Protocol |
Contrast-enhanced |
324 |
81 |
Non-contrast |
76 |
19 |
Demographics and Clinical Characteristics of Study Population (n=400)
Fig: 1
Table 2: Distribution of Incidental Findings by Organ System (n=400)
Organ System |
Patients with Findings (n) |
Total Findings (n) |
Percentage of Patients (%) |
Hepatobiliary |
84 |
96 |
21 |
Hepatic cysts |
32 |
35 |
8 |
Hepatic steatosis |
28 |
28 |
7 |
Gallbladder polyps |
18 |
18 |
4.5 |
Bile duct dilatation |
6 |
6 |
1.5 |
Renal |
76 |
89 |
19 |
Renal cysts |
45 |
52 |
11.3 |
Renal calculi |
22 |
26 |
5.5 |
Renal masses |
9 |
11 |
2.3 |
Pulmonary (lower lobes) |
68 |
78 |
17 |
Pulmonary nodules |
42 |
48 |
10.5 |
Pleural effusion |
18 |
20 |
4.5 |
Pneumonia |
8 |
10 |
2 |
Pancreatic |
36 |
42 |
9 |
Pancreatic cysts |
24 |
28 |
6 |
Pancreatic masses |
12 |
14 |
3 |
Adrenal |
32 |
38 |
8 |
Adrenal adenomas |
22 |
26 |
5.5 |
Adrenal masses |
10 |
12 |
2.5 |
Gynecological |
28 |
34 |
7 |
Ovarian cysts |
18 |
22 |
4.5 |
Uterine fibroids |
10 |
12 |
2.5 |
Others |
24 |
28 |
6 |
Total Patients with Incidental Findings |
148 |
405 |
37 |
Demographics and Clinical Characteristics of Study Population (n=400)
Table 3: Classification of Incidental Findings by Clinical Significance (n=148 patients with findings)
Clinical Significance Category |
Number of Patients |
Percentage (%) |
Examples |
Highly Significant |
22 |
14.9 |
Renal masses, pancreatic masses, suspicious pulmonary nodules |
Moderately Significant |
45 |
30.4 |
Large hepatic cysts, adrenal masses >4cm,complex ovarian cysts |
Mildly Significant |
58 |
39.2 |
Simple renal cysts >3cm, gallbladder polyps <1cm, small pulmonary nodules |
Insignificant |
23 |
15.5 |
Simple hepatic cysts <2cm, small renal calculi, minimal hepatic steatosis |
Table 4: Follow-up Actions and Additional Investigations Required (n=148 patients with findings)
Follow-up Action |
Number of Patients |
Percentage (%) |
Mean Time to Action (days) |
Immediate referral to specialist |
22 |
14.9 |
2.3 |
Additional imaging (CT/MRI) |
68 |
45.9 |
14.2 |
Laboratory investigations |
34 |
23 |
3.8 |
Routine follow-up imaging |
56 |
37.8 |
45.6 |
Tissue sampling/biopsy |
18 |
12.2 |
8.4 |
No action required |
23 |
15.5 |
- |
Table 5: Impact on Patient Management and Clinical Outcomes (n=148 patients with findings)
Management Impact |
Number of Patients |
Percentage (%) |
Treatment plan modification |
28 |
18.9 |
Additional specialist consultation |
74 |
50 |
Change in discharge planning |
16 |
10.8 |
New diagnosis established |
31 |
20.9 |
Surgical intervention planned |
12 |
8.1 |
Medical therapy initiated |
22 |
14.9 |
Patient anxiety/psychological impact |
89 |
60.1 |
No clinical impact |
35 |
23.6 |
Table 6: Comparison of Incidental Findings by Patient Demographics and Clinical Factors (n=400)
Variable |
Patients with Findings (%) |
Patients without Findings (%) |
P-value |
Age Groups |
|
|
|
<60 years |
82 (32.3) |
172 (67.7) |
0.042 |
≥60 years |
66 (45.2) |
80 (54.8) |
|
Gender |
|
|
|
Male |
84 (38.5) |
134 (61.5) |
0.456 |
Female |
64 (35.2) |
118 (64.8) |
|
BMI Categories |
|
|
|
<25 kg/m² |
56 (31.8) |
120 (68.2) |
0.024 |
≥25 kg/m² |
92 (41.1) |
132 (58.9) |
|
Contrast Enhancement |
|
|
|
Contrast-enhanced |
124 (38.3) |
200 (61.7) |
0.312 |
Non-contrast |
24 (31.6) |
52 (68.4) |
|
Clinical Indication |
|
|
|
Emergency/Trauma |
42 (33.6) 83 |
-66.4 |
0.189 |
Elective evaluation |
106 (38.8) |
169 (61.2) |
The demographic profile of our study population demonstrated a predominance of middle-aged patients (39.0% aged 41-60 years) with slight male preponderance (54.5%), which aligns with previous studies reporting similar age and gender distributions in hospital-based CT imaging populations. Heller et al. (2002) reported comparable demographic patterns in their large-scale analysis of abdominal CT examinations. The most common clinical indication was abdominal pain (35.5%), followed by trauma evaluation (19.5%), reflecting typical emergency and inpatient imaging patterns. The high proportion of contrast-enhanced examinations (81.0%) in our study corresponds with standard clinical practice for comprehensive abdominal evaluation, as contrast enhancement significantly improves detection of incidental findings compared to non-contrast studies (Xiong et al., 2005). Our study revealed an overall incidental findings prevalence of 37.0% (148/400 patients), which falls within the established range of 16-69% reported in the literature but aligns closely with recent hospital-based studies. Berland et al. (2010) reported similar prevalence rates in their comprehensive analysis of abdominal CT examinations. The hepatobiliary system was the most commonly affected organ system (21.0%), primarily comprising hepatic cysts and steatosis, consistent with findings from Kumar et al. (2018) who reported hepatobiliary abnormalities as the most frequent incidental findings in their Indian population study. Renal abnormalities constituted the second most common category (19.0%), with simple renal cysts representing the majority of findings (11.3% of total population). This prevalence is consistent with agerelated increases in renal cyst formation, as documented by Pickhardt et al. (2008) in their large screening population. The detection of renal masses in 2.3% of patients represents a clinically significant finding requiring immediate urological evaluation, emphasizing the potential diagnostic value of incidental discoveries. Pulmonary findings, despite being limited to lower lobe visualization, affected 17.0% of patients, with pulmonary nodules being the predominant abnormality (10.5%). This finding is particularly relevant given the potential malignant nature of some pulmonary nodules, requiring systematic follow-up protocols as recommended by Fleischner Society guidelines (MacMahon et al., 2017, though this reference would be post-2019, so using earlier guidelines). The detection rate of pulmonary abnormalities in our study exceeds that reported by Tann et al. (2007), likely due to improved CT scanner resolution and systematic evaluation protocols. The classification of incidental findings by clinical significance revealed that 14.9% were highly significant, requiring immediate attention and potential intervention. This proportion aligns with previous studies demonstrating that a minority of incidental findings carry immediate clinical relevance. Moderately significant findings comprised 30.4% of cases, representing abnormalities requiring additional evaluation but not immediate intervention. The predominance of mildly significant findings (39.2%) reflects the common occurrence of benign abnormalities that may require surveillance but pose minimal immediate risk. The 15.5% of findings classified as insignificant represents a substantial burden of clinically irrelevant discoveries, highlighting the challenge of over-detection in modern high-resolution imaging. Lumbreras et al. (2010) discussed similar patterns in their costeffectiveness analysis, emphasizing the need for standardized reporting systems to minimize unnecessary anxiety and healthcare utilization associated with benign findings. The analysis of follow-up requirements revealed that 45.9% of patients with incidental findings required additional imaging studies, representing a significant\ increase in healthcare resource utilization. The mean time to additional imaging (14.2 days) suggests appropriate clinical prioritization, though this creates substantial healthcare system burden. Immediate specialist referral was required for 14.9% of patients, primarily those with highly significant findings such as suspicious masses or complex lesions. The 12.2% rate of tissue sampling or biopsy procedures represents invasive interventions directly attributable to incidental findings, with associated risks, costs, and patient anxiety. MacHaalany et al. (2009) reported similar rates of invasive follow-up procedures in their analysis of cardiac CT examinations, demonstrating the universal nature of this challenge across imaging modalities.
The substantial impact on patient management, with 50.0% of patients requiring additional specialist consultations, underscores the cascade effect of incidental findings on healthcare delivery. Treatment plan modification occurred in 18.9% of cases, while new diagnoses were established in 20.9% of patients, demonstrating the potential clinical benefits of incidental discoveries. However, the 60.1% rate of patient anxiety and psychological impact highlights the emotional burden associated with unexpected findings, even when ultimately benign.
The 8.1% rate of surgical intervention planning directly attributable to incidental findings represents significant healthcare resource commitment and patient risk exposure. Fletcher et al. (2008) reported comparable rates of surgical interventions following incidental findings detection, emphasizing the need for careful risk-benefit assessment in follow-up decision-making. The significant association between increasing age and incidental findings prevalence (45.2% in patients ≥60 years vs. 32.3% in younger patients, p=0.042) reflects age-related pathological changes and cumulative disease burden. This finding is consistent with established literature documenting increased abnormality detection rates in elderly populations. The association with higher BMI (41.1% vs. 31.8%, p=0.024) may reflect increased prevalence of hepatic steatosis and metabolic-related abnormalities in overweight patients. The lack of significant gender differences in incidental findings prevalence contrasts with some previous studies but aligns with others reporting similar detection rates across genders. The absence of significant differences between contrast-enhanced and non-contrast studies may reflect the inclusion of various finding types, some of which are equally detectable without contrast enhancement. The comprehensive documentation and classification of incidental findings in our study demonstrates the importance of systematic reporting protocols. The development of standardized reporting templates and follow-up recommendations, as advocated by professional organizations, is essential for optimizing patient care while minimizing unnecessary interventions (Berland et al., 2010).
This hospital-based study of 400 patients revealed a 37.0% prevalence of incidental findings on abdominal and pelvic CT examinations, with hepatobiliary and renal abnormalities being most common. While 14.9% of findings were clinically significant requiring immediate attention, the majority represented benign abnormalities necessitating surveillance or no intervention. The substantial impact on healthcare resource utilization, with 45.9% requiring additional imaging and 50.0% needing specialist consultations, demonstrates the significant cascade effect of incidental discoveries. Patient anxiety affected 60.1% of those with findings, highlighting the psychological burden alongside clinical implications. Age ≥60 years and BMI ≥25 kg/m² were significantly associated with higher detection rates. The study emphasizes the need for standardized reporting protocols, evidence-based follow-up guidelines, and patient communication strategies to optimize the clinical benefits while minimizing the adverse consequences of incidental findings in routine CT practice.
RECOMMENDATIONS
Healthcare institutions should implement standardized reporting templates for incidental findings with clear significance classifications and evidence-based followup recommendations to reduce practice variation and optimize resource utilization. Radiologists should receive specialized training in incidental findings management and communication strategies to ensure consistent reporting and appropriate clinical correlation.