Differential Diagnosis
- Single most likely diagnosis
- Normal variant or non-specific headache: The x-ray of the skull is within normal limits, and there is no evidence of acute fracture or other abnormalities, making a normal variant or non-specific headache the most likely diagnosis.
- Other Likely diagnoses
- Tension headache: Given the lack of structural abnormalities, tension headache is a possible diagnosis, as it is a common cause of headache without specific radiographic findings.
- Migraine: Migraines can also present without specific radiographic abnormalities, making it another possible diagnosis.
- Sinusitis (early or mild): Although the maxillary sinuses and ethmoid air cells are reported as unremarkable, early or mild sinusitis might not be evident on a plain x-ray, and clinical correlation is necessary.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Subarachnoid hemorrhage: Although the x-ray does not show any evidence of fracture, a subarachnoid hemorrhage could still occur without a visible fracture, especially if it is a non-traumatic cause. Clinical correlation and possibly a CT scan of the brain are crucial.
- Intracranial hemorrhage: Similar to subarachnoid hemorrhage, other types of intracranial hemorrhages (e.g., intraparenchymal, epidural, subdural) might not be visible on a plain skull x-ray and require further imaging like a CT scan for diagnosis.
- Cerebral venous sinus thrombosis: This condition can present with headache and might not have specific findings on a plain x-ray of the skull, making it a "do not miss" diagnosis that requires clinical suspicion and possibly a CT or MRI scan for diagnosis.
- Rare diagnoses
- Arteriovenous malformation (AVM): AVMs can cause headaches and might not be visible on a plain x-ray. They are rare but require consideration in the differential diagnosis, especially if other symptoms or signs are present.
- Brain tumor: Although rare, brain tumors can present with non-specific headaches. The lack of findings on the x-ray does not rule out this possibility, and further imaging might be necessary based on clinical suspicion and other diagnostic criteria.