1. Deciding extent of FESS
In radiation recurrent malignancy, treatment is done according to tumor size before radiation i.e. pretreatment tumor status. In similar lines for chronic sinusitis surgical treatment is given based on premedical treatment sinus status. This may mean a total Sphenofronto ethmoidectomy even for minor polyposis. Experience has shown, if this is not done recurrence rates are high.
2. Is this the actual skull base? The sinuses are limited superiorly by the anterior skull base which is hard dense bone to feel as seen in figure. Para nasal sinuses are filled with air and papery thin septae divide them into various cells. Chronic infection of the sinuses causes thickening of these septae due to various mediators of inflammation. The important principle of FESS is good clearance of sinuses with out leaving any polypogenic tissue and unopened air cells in the sinuses to prevent recurrence. Due to chronic infection of the sinuses the thin septae become thickened and gives resistance while removing the cells, on palpation these septae are felt like hard bone giving a false impression of the skull base. Hence they are not cleared and result in recurrence of disease Orientation of the endoscopic anatomy with good visualization of the sinuses helps to overcome this pitfall.
The sinuses are limited superiorly by the anterior skull base which is hard dense bone to feel as seen in figure. Para nasal sinuses are filled with air and papery thin septae divide them into various cells. Chronic infection of the sinuses causes thickening of these septae due to various mediators of inflammation. The important principle of FESS is good clearance of sinuses with out leaving any polypogenic tissue and unopened air cells in the sinuses to prevent recurrence. Due to chronic infection of the sinuses the thin septae become thickened and gives resistance while removing the cells, on palpation these septae are felt like hard bone giving a false impression of the skull base. Hence they are not cleared and result in recurrence of disease Orientation of the endoscopic anatomy with good visualization of the sinuses helps to overcome this pitfall.