Answer for BIR CoW 08 Mar 2026
Fetal lung malformation
Findings
Single intra-uterine gestation Placenta- fundal posterior Evidence of multiple T2 hyperintense cystic lesion of varying sizes replacing lower lobe of right lung, predominantly microcystic measuring 3x3x1.8cm. CPAM volume ratio-0.38 DIAGNOSIS Suggestive of Congenital pulmonary airway malformation[CPAM]- type II involving lower lobe of right lung.
Discussion
Congenitary Pulmonary Airway Malformation(CPAM)25% It results from embryological insult of bronchial tree before seventh week of gestation, with overproduction of terminal bronchiolar structures without alveolar differentiation. The resulting cystic lesion cause enlargement of affected lobes[segment]. If large, cause mediastinal shift, cardiac and venacava compression * It shows communication with tracheobronchial tree, and vascular supply by pulmonary circulation,unless associated with sequestration[hybrid lesion] * Types are I[large cyst 2-10cm], II[multiple small cysts], III[microcystic, appears echogenic] * CPAM volume ratio[CVR]- volume of lung mass x 0.52 and dividing it by head circumference. CVR > 1.6, risk of fetal hydrops is 75%.
Reference - Rumack textbook of diagnostic ultrasound
Findings
Single intra-uterine gestation Placenta- fundal posterior Evidence of multiple T2 hyperintense cystic lesion of varying sizes replacing lower lobe of right lung, predominantly microcystic measuring 3x3x1.8cm. CPAM volume ratio-0.38 DIAGNOSIS Suggestive of Congenital pulmonary airway malformation[CPAM]- type II involving lower lobe of right lung.
Discussion
Congenitary Pulmonary Airway Malformation(CPAM)25% It results from embryological insult of bronchial tree before seventh week of gestation, with overproduction of terminal bronchiolar structures without alveolar differentiation. The resulting cystic lesion cause enlargement of affected lobes[segment]. If large, cause mediastinal shift, cardiac and venacava compression * It shows communication with tracheobronchial tree, and vascular supply by pulmonary circulation,unless associated with sequestration[hybrid lesion] * Types are I[large cyst 2-10cm], II[multiple small cysts], III[microcystic, appears echogenic] * CPAM volume ratio[CVR]- volume of lung mass x 0.52 and dividing it by head circumference. CVR > 1.6, risk of fetal hydrops is 75%.
Reference - Rumack textbook of diagnostic ultrasound
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
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Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!