Computerised tomographic profile of ethmoid roof on basis of keros classification among ethnic Kashmiri’s

Imran Nazir Salroo, Nisar Hussain Dar, Aamir Yousuf, Kousar Sideeq Lone


Background: The purpose of this study was to evaluate the ethmoid roof on computerized tomography of nose and paranasal sinuses of Kashmiri people and distribute them on basis of KEROS classification.

Methods: Cross sectional descriptive study, the randomly selected paranasal sinus computed tomography (PNS CT) scans coronal cuts .Total of One hundred PNS CT scans done at the SMHS Hospital from April 2015 to September 2015 were reviewed, and selected for study. The bilateral heights of the lateral lamellae of the cribriform plate were obtained, independently coded, and classified according to keros.

Results: The mean height of the lateral lamella among Kashmir’s was seen to be 5.08mm and 29% of patient’s CT PNS were classified as Keros I, 61% were classified as Keros II and 10% were classified as Keros III. There was significant difference in the distribution of Keros classification between the right and left lateral lamella. There was no significant difference in the height of the lateral lamella (t-test: p=0.98 on right side & p =0.89 on left side) and the distribution of Keros classification (Fisher’s Exact test: p = 0.823) among younger (1-14 year) and older (>14 year) Kashmiri age groups. There is significant difference in the height (t-test: p=0.03 on right side and p=0.03 on left side) and the distribution of Keros classification is statistically insignificant (Fishers Exact Test: p=0.11) between Kashmiri females and males.

Conclusions: Preoperative assessment of ethmoid roof anatomy and keros level is mandatory for alerting the surgeon of the potential iatrogenic injury during endoscopic sinus surgeries to minimize the grave complications during ESS.


Tomography, Ethmoid roof, KEROS, Kashmir

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