Periodicity is a characteristic feature in which sinus infection:
High-Yield Explanation
Areas of High attenuation surrounded by a thin zone of low attenuation CT scan reveals pansinusitis and polyposis Pain of frontal sinusitis shows characteristic periodicity, i.e. comes upon waking, gradually increases and reaches its peak by midday and then stas subsiding. It is also called "office headache" as it is present only during office hours.