Morphometric study of cricoid cartilages in Western India

It is important to determine the size and proportion of the larynx as such information is useful in procedures such as intubation, endoscopy and surgical manipulations. Recent interest in the cases of subglottic stenosis and postintubational stenosis of the lower respiratory tract has led to renewed interest in ascertaining the measurements of the various laryngeal cartilages. The aim of the present study was to collect morphometric data of cricoid cartilage from a regional population.

Fifty laryngeal preparations from adult cadavers of Western India were assessed. Sections were prepared via dissection and the removed cricoid cartilages then measured and weighed.

The mean antero-posterior diameter (19.29±2.47) of the cricoid cartilage was greater than the average transverse diameter (18.33±2.26). The height of arch of cricoid cartilage was 6.54±1.23mm and height of lamina was 21.45±1.97mm. Mean weight of cricoid cartilage was 4.53±1.27grams. The shape of the cricoid cartilage was ovoid in 46% of cases, oval in 38%, pear shaped in 12% and narrow-oblong in 4% of cases.

Inter-subject variability in the dimensions of cricoid cartilages was observed. The large difference in almost all sizes and shapes of the cricoid cartilage makes it difficult to standardise the rigid stents used in these organs. Endotracheal tubes of the appropriate size should therefore be based on the measurements of individual patients. Clinicians should therefore be aware of morphological variations as they are of fundamental clinical importance.