Following are the meaning of these words;
1) lacunar infarcts; are loss of blood supply in different parts of brain (deeper parts of brain are involved). Lacunar infarcts are small (0.2 to 15 mm in diameter) loss of blood supply usually related to high blood pressure of long standing. These have good prognosis and many times do not cause any symptoms.
2) atherosclerotic encephalopathy; There can be multiple areas in the brain with the loss of blood supply; thus it is called as multi-infarct dementia. Damage occurs to the white brain matter. Loss of memory, intellectual functions and changes in mood may be found in those effected. It is associated with hypertension (high blood pressure).
3) subarachnoid space; our brain is covered by a covering called as meninges. It protects the brain. It has three layers called the dura mater, the arachnoid mater, and the pia mater. The arachnoid is the middle layer and space just below the arachnoid is called as subarachnoid space.
4) ethmoid sinus; sinus are hollow parts in our face bones. This (a pair of ethmoid sinus) is around the nose and are connected with it. Allergies and infection of the nose can cause sinusitis.
The CT scan findings have to corroborated to the clinical findings (symptoms, signs and physical examination findings) for a conclusive diagnosis. The medical imaging assists in the diagnosis and alone it may not be able to give a concrete diagnosis.
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