The papillary process of the caudate lobe, also known as the medial papillary process, represents a division of the inferior caudate lobe of the liver 1. The inferior aspect of the caudate may be divided into medial and lateral processes. While the lateral or caudate process is contiguous with the right liver lobe, the medial or papillary process extends leftward and towards the stomach 1,3.
There is variable morphology of the inferior caudate lobe. Often, a sagittally-oriented inferior fissure or groove separates the lateral caudate and medial papillary processes. The papillary process itself may extend anteriorly or inferiorly to protrude into the superior recess of the lesser sac 3.
It is important to remain cognizant of the papillary process of the caudate on cross-sectional imaging, as it can often be mistakenly interpreted. Due to its leftward projection and (variable) fissure separation from the medial process, the papillary process usually appears discontinuous from the rest of the liver on at least one axial CT slice. Thus it can be mistaken for a lymphadenopathy or a pancreatic body mass, particularly when congenitally hypertrophied (variant anatomy) or enlarged from cirrhosis 1,3. The papillary process can be confidently identified on the basis of contiguity with the rest of the caudate lobe.
- 1. Auh YH, Rosen A, Rubenstein WA, Engel IA, Whalen JP, Kazam E. CT of the papillary process of the caudate lobe of the liver. (1984) AJR. American journal of roentgenology. 142 (3): 535-8. doi:10.2214/ajr.142.3.535 - Pubmed
- 2. Donoso L, Martínez-Noguera A, Zidan A, Lora F. Papillary process of the caudate lobe of the liver: sonographic appearance. (1989) Radiology. 173 (3): 631-3. doi:10.1148/radiology.173.3.2682770 - Pubmed
- 3. Dodds WJ, Erickson SJ, Taylor AJ, Lawson TL, Stewart ET. Caudate lobe of the liver: anatomy, embryology, and pathology. (1990) AJR. American journal of roentgenology. 154 (1): 87-93. doi:10.2214/ajr.154.1.2104732 - Pubmed