Headache is among the most frequent complaints encountered in clinical practice and is a leading cause for neuroimaging referrals. Although the majority of headaches are primary in nature, such as migraine or tension-type headache, imaging is often performed to exclude secondary causes.

With the widespread availability of advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging (MRI), incidental findings are increasingly being detected. Incidental findings are defined as unexpected abnormalities that are unrelated to the patient’s presenting complaint. These findings may range from benign anatomical variants to potentially serious pathologies.

The detection of incidental findings presents a clinical dilemma, as it may lead to unnecessary anxiety, additional investigations, and increased healthcare costs. On the other hand, some incidental findings may have clinical significance and require further evaluation.

Previous studies have reported incidental findings in 10–30% of neuroimaging performed for headache. However, there is limited data from Indian settings. Therefore, the present study aims to assess the prevalence and spectrum of incidental findings in patients undergoing CT/MRI brain for headache

Study Design and Setting

Hospital-based cross-sectional study conducted in the Department of Radiodiagnosis over a period of 1 year.

Study Population

Patients presenting with headache and referred for CT or MRI brain.

Sample Size

A total of 220 patients were included.

Inclusion Criteria

• Patients aged ≥18 years
• Presenting with headache
• Undergoing CT/MRI brain

Exclusion Criteria

• Known intracranial pathology
• History of trauma
• Previous neurosurgery

Imaging Protocol

• CT brain: Non-contrast CT
• MRI brain: T1, T2, FLAIR sequences

Data Categorization

Findings were classified into:

1. Normal
2. Pathological findings related to headache
3. Incidental findings unrelated to headache

Statistical Analysis

• Descriptive statistics
• Chi-square test
• p < 0.05 considered significant

A total of 220 patients presenting with headache and undergoing neuroimaging were included in the study. The mean age of the participants was 35 ± 12 years, indicating a wide age distribution ranging from young adults to middle-aged individuals. Females constituted the majority of the study population (60%), while males accounted for 40%, suggesting a higher healthcare-seeking behavior or prevalence of headache among females in this cohort.

With regard to imaging outcomes, the majority of patients (62%) had normal neuroimaging findings, indicating no detectable structural abnormality on CT or MRI brain. Pathological findings directly related to the presenting complaint of headache were observed in 18% of patients. These included conditions such as intracranial masses, infections, hydrocephalus, and vascular abnormalities, which warranted further clinical evaluation and management. Notably, incidental findings—defined as abnormalities unrelated to the cause of headache—were identified in 20% of the study population, highlighting their relatively common occurrence in routine neuroimaging.

Among the incidental findings, sinusitis was the most frequently observed, accounting for 8% of cases. Although often detected on imaging, sinusitis may not necessarily be the primary cause of headache in all patients. Benign cystic lesions, including arachnoid and pineal cysts, were identified in 4% of individuals and were largely asymptomatic. White matter changes, suggestive of small vessel ischemic disease or age-related alterations, were seen in 3% of patients. Intracranial calcifications were present in 2% of cases and were mostly incidental with no clinical significance. Other findings, including vascular variants and mild cerebral atrophy, were observed in 3% of participants.

Further analysis revealed a statistically significant association between age and the occurrence of incidental findings. Patients aged above 40 years showed a higher prevalence of such findings compared to younger individuals (p < 0.05). This trend may be attributed to age-related structural changes in the brain and increased likelihood of subclinical pathologies in older populations.

Overall, the results demonstrate that while most neuroimaging studies in patients with headache are normal, a considerable proportion reveals incidental findings. These findings emphasize the importance of careful interpretation and clinical correlation to avoid unnecessary investigations and patient anxiety.

The present study found that incidental findings were present in 20% of patients undergoing neuroimaging for headache, which is consistent with previous studies reporting prevalence rates between 10% and 30%. The majority of imaging studies were normal, reinforcing the fact that most headaches are primary in nature and do not require imaging.

Among incidental findings, sinusitis was the most common, followed by benign cysts and white matter changes. Sinusitis is frequently detected on imaging and is often unrelated to headache symptoms, although it may occasionally contribute to secondary headaches. Benign cysts such as arachnoid and pineal cysts are usually asymptomatic and detected incidentally.

White matter changes observed in this study may be associated with age-related changes or vascular risk factors. These findings were more common in older individuals, which explains the significant association with increasing age.

The detection of incidental findings poses a challenge for clinicians. While most findings are benign and require no intervention, some may necessitate further evaluation. Therefore, careful interpretation and clinical correlation are essential to avoid unnecessary investigations and patient anxiety,

Incidental findings are relatively common in CT and MRI brain imaging performed for patients presenting with headache, as demonstrated in the present study. The majority of these findings are benign, such as sinusitis, benign cysts, or age-related changes, and are often not directly related to the patient’s symptoms. However, their detection can lead to unnecessary, additional investigations, and increased healthcare burden if not interpreted appropriately. Therefore, it is essential for clinicians and radiologists to carefully correlate imaging findings with clinical presentation. A judicious and evidence-based approach is crucial to avoid overdiagnosis, ensure appropriate management, and provide reassurance to patients when findings are clinically insignificant

Limitations

• Single-center study
• Limited sample size
• Lack of follow-up

Recommendations

• Avoid unnecessary imaging in primary headache
• Develop guidelines for incidental findings management
• Patient counseling to reduce anxiety

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