An anatomical study on pyramidal lobe of thyroid gland in Bangladeshi people.

The study was done to see the incidence of pyramidal lobe of thyroid gland including its position, attachment, length and incidence of its association with levator glandulae thyroidae in Bangladeshi population. Sixty postmortem tissue blocks containing thyroid gland and its related neighbouring structures were collected from 48 male and 12 female cadavers of different age groups and fixed in 10% formol-saline solution. Gross and fine dissection was carried out to study the incidence of presence of pyramidal lobe, its attachments, length, breadth and association with levator gladulae thyroidae. In the present study, findings were compared with those of Western and Bangladeshi researchers. It was evident that, fifty percent of the thyroids possesses pyramidal lobe. Incidence was more in male (52.1%) than in female (41.7%). It also appeared from the observations that, this lobe was commonly situated on the left side. In the majority of cases (56.66%), base of the pyramidal lobes were attached to the upper border of the isthmus with or without encroachment on the adjacent part of the left lobe. The range of length and breadth of the pyramidal lobe was from 1.8 to 35mm and 1.3 to 19mm respectively. In 73.33% cases, pyramidal lobe was associated with levator glandulae thyroideae and in only 26.66% cases pyramidal lobe was found independently.