Differential Diagnosis
- Single most likely diagnosis
- Arteriovenous malformation (AVM): The presence of calcifications in the left occipital region on the CT scan, along with the patient's history of progressively severe headaches and the sudden onset of a severe headache with visual loss, suggests an AVM. The partial resolution of the dense right homonymous hemianopia during the examination could be due to the dynamic nature of an AVM, which can cause intermittent symptoms due to changes in blood flow.
- Other Likely diagnoses
- Migraine with aura: The patient's history of severe headaches on one side that initially responded to over-the-counter analgesics could suggest migraines. However, the sudden onset of a severe headache with visual loss and the presence of calcifications on the CT scan make this diagnosis less likely.
- Subarachnoid hemorrhage: Although the patient presents with a severe headache, the lack of other symptoms such as neck stiffness, fever, or altered mental status, and the presence of calcifications on the CT scan, make this diagnosis less likely.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Acute cerebral infarction: Although the patient's symptoms are not typical for a stroke, it is essential to consider this diagnosis due to the potential for severe consequences if left untreated. The presence of a dense right homonymous hemianopia could be indicative of a posterior circulation stroke.
- Subdural hematoma: The patient's history of severe headaches and the sudden onset of a severe headache with visual loss could be indicative of a subdural hematoma, especially if there is a history of trauma. However, the lack of other symptoms such as altered mental status or focal neurologic deficits makes this diagnosis less likely.
- Rare diagnoses
- Carotid cavernous fistula: This diagnosis is unlikely due to the lack of other symptoms such as pulsatile exophthalmos, chemosis, or a bruit over the orbit.
- Epidural hematoma: The patient's symptoms and the presence of calcifications on the CT scan make this diagnosis unlikely. Epidural hematomas typically present with a loss of consciousness, focal neurologic deficits, and a history of trauma.