The utility of computed tomography scan in evaluation of patients with non acute headache and normal neurologic examination in Nairobi
Objectives To assess the utility of computed tomogram scan (CT scan) in neuroimaging of patients presenting with non acute headache and normal neurologic examination, and to determine the pathological yield in terms of qualifications of referring doctor, age, sex, duration of headache and type of clinically diagnosed headache syndromes. BACKGROUND: Headache is one of the most common reasons why patients go to see a doctor. Majority may not have a serious cause for the headache but a minority will. Headache is majorly classified into primary and secondary headache. Primary headache is a type of headache which is not associated with any demonstrable organic disease or structural neurologic abnormality, on the other hand, secondary headaches include those headaches caused by underlying medical condition. Primary headache is the commonest type of headache. Neuroimaging for primary headaches yields very low intracranial positive results for pathology. Despite this being the fact, patients with primary headache are referred in-discriminatively for head CT scan. There is no local study done on use of CT scan as part of investing patients with non acute headache and normal neurological examination. It is important to study the pattern of patient referrals in Nairobi for Head CT scan in patients with primary headache and find out whether the primary clinicians do make a specific clinical diagnosis before referring. The level of positive pathological yields will be a good indicator on whether this examination is necessary, hence provide basis for the development of a guideline to be followed before doing neuroimaging on these patients in Nairobi. METHOD: One hundred cases that were referred to Kenyatta national hospital and Plaza imaging solutions for head CT scans with complaints of non acute headaches without focal neurological deficit, were recruited into the study after signing an informed consent. The patients were recruited through convenient sampling. The researcher went through the request forms and administered the questionnaire to the patients before including them into the study. This was done prior to doing the CT scan examination. The patients were recruited randomly from all the patients send for imaging in these facilities during the period of study. The researcher reviewed the images with a qualified specialist Radiologist. All these variables were analyzed to find out the proportion and characteristics of study cases that had identifiable abnormalities. Age, sex, duration of headache, type of headache, qualification of referring doctors and the distribution of CT findings were described from a frequency table. RESULTS Mean age of the cases was 36.7 (SD16.6) years. Majority were female making 65%. 78% were referrals from medical officers and Only two patients ( 2%) had findings of solid intracranial and base of skull pathological lesions. The two were referrals from consultant neurologists. 44% had normal head CT scan findings, 43% rhino sinusitis, 8% had brain atrophy and 3% had mastoiditis. CONCLUSION: In patients with non acute headache and normal neurological examination, intra cranial pathological yield was too low. Therefore, there is need to establish a guideline to be followed before referring these patients for head CT scan. Significant extra cranial pathologies were detected. Most of the patients did not have definite clinical diagnosis. If clinicians did adequate clinical examination and took thorough clinical history, they would have requested for more focused imaging examination like paranasal sinus CT scan or high resolution temporal bone CT scan examination and not head CT scan.