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Introduction: The thymus is located in the superior mediastinum and anterior part of the inferior mediastinum. It plays a crucial role in the development, differentiation, and clonal expansion of T lymphocytes. In forensic cases involving foetal death, accurate estimation of foetal age is essential. When the foetus is extensively damaged, other organs can be used to estimate age. The thymus, being retrosternal and well-protected, is easily accessible during dissection. Therefore, studying the gross features and histogenesis of the thymus can be helpful in estimating gestational age in cases of severely mutilated foetal specimens. Aim: To examine the morphological features and histogenesis of the thymus in aborted and stillborn foetuses from normal pregnancies. Materials and Methods: A pilot study was conducted using a cross-sectional design at the Department of Anatomy, BLDEDU’s Shri BM Patil Medical College, Vijayapura, Karnataka, India, from May 2016 to April 2018. The dimensions and histogenesis of the thymus were studied in a total of 50 human foetal thymus specimens, collected from normal pregnancies across different gestational age groups ranging from 12 to 40 weeks. The specimens were obtained from the Department of Pathology and the Department of Obstetrics and Gynaecology. The dimensions and weight of the thymus were recorded during autopsy. Slides were prepared, stained with Haematoxylin and Eosin (H&E), and examined under a compound microscope. The histogenesis of the thymus was studied to observe its maturation. Results: Foetal weight increased from 134.6±58.3 g at 12 weeks to 1942±598 g at 40 weeks. The weight of the thymus ranged from 0.2 g at 12 weeks to 5.9 g at 40 weeks. Crown rump length varied from 10.7 cm to 29.9 cm. The length of the thymus measured between 0.5 cm and 3.3 cm, breadth between 0.4 cm and 2.3 cm, and height between 0.2 cm and 0.9 cm from 12 to 40 weeks of gestation. Microscopic features observed in the present study at different gestational ages included a well-formed thick capsule at 17 weeks, lobulation starting at 19 weeks, cortico-medullary differentiation beginning at 17 weeks, appearance of epithelial cells around 19 weeks, and initial appearance of Hassal’s corpuscles at 17 weeks, with more numbers observed later on. Conclusion: The thymus can be used in forensic investigations to estimate the gestational age of mutilated foetuses. It exhibits varying features at different gestational ages, which can aid in thymectomy procedures. Additionally, these findings can be considered during prenatal imaging studies.

During routine cadaveric dissection for students, the authors found variations in three cadavers. A male cadaver of approximately 70 years of age showed a unique branch communicating the coeliac trunk with the Superior Mesenteric Artery (SMA). The right and left hepatic arteries gave smaller branches before entering into liver. In another male cadaver of approximately 60 years of age, the left hepatic artery was arising from the left gastric artery. The common hepatic artery gave rise to right gastric artery and gastroduodenal artery, after which it continued as right hepatic artery proper. This gave rise to cystic artery. The present series also observed quadrifurcation of coeliac trunk in a male cadaver of 70 years of age. It gave off four branches namely, splenic artery, left gastric artery, right hepatic artery and left hepatic artery. The gastroduodenal artery was arising from the left hepatic artery. The variations in the branching pattern of coeliac trunk is important for the surgeons during gastric surgeries, liver transplantation, pancreatic and gall bladder surgeries. Radiologists should be aware of such variations during reporting of Computed Tomography (CT) angiograms.

The thoracic aorta extends from lower border of fourth thoracic vertebra upto the aortic hiatus of thoraco-abdominal diaphragm at the lower border of 12th thoracic vertebra. Then it continues as abdominal aorta upto lower border of fourth lumbar vertebra where it terminates as common iliac arteries. Commonly the facial, superficial temporal, splenic artery have tortuous course which are routinely taught to the undergraduate students. During routine dissection we noticed variations in the thoracic and abdominal aorta in a female cadaver, approximately 60 years of age. The thoracic and the abdominal aorta were found to have a tortuous course instead of a straight course. The bilateral renal arteries were also tortuous. Further the bilateral common iliac and internal and external iliac arteries were also tortuous in their course. Such a case of multiple arteries being tortuous indicates a possibility of arterial tortuosity syndrome which is autosomal recessively inherited. Familial screening is also needed in such cases. Marked tortuosity of the arteries may be an incidental finding and if so, should raise a suspicion for the underlying clinical condition and search for its cause. These many curves in the course of aorta are hazardous for any patient during vascular procedures. Probabilities of blockage or rupture of the arteries increase with the number of twists in the arteries.