SENSITIVITY OF ULTRASONOGRAPHY IN THE EARLY DIAGNOSIS OF CHOLELITHIASIS AMONG PATIENTS AGED 20–40 YEARS: A CROSS-SECTIONAL STUDY IN DERA ISMAIL KHAN, PAKISTAN. Pakistan Journal of Medical & Cardiological Review, [S. l.], v. 5, n. 2, p. 5899–5920, 2026. DOI: 10.66021/pakmcr1433. Disponível em: https://pakjmcr.com/index.php/1/article/view/1433. Acesso em: 20 aug. 2026.