THE LIVER SEGMENTATION AND VOLUMETRY UNRESOLVED ISSUES AND CLINICAL SIGNIFICANCE

Modern methods of medical imaging have contributed to the emergence of new technologies and trends in liver medicine – liver segmentation, which is the process of dividing the organ into functionally independent segments with an individual system of blood supply, venous outflow and excretion of bile and its volumetry (volume-metry – measurements and assessment of the functional volumes of the organ). Given the significant variability of the shape, size, volume, features of the blood supply not only of the liver as a whole, but also of each of its segments, performing accurate segmentation of this organ remains a complex task. The objective of the review is to analyze classical and alternative systems of liver segmentation, which are anatomical and functional models of the organ. Their advantages and disadvantages are highlighted. Particular attention is paid to radiation methods of liver visualization with consideration of the range of their capabilities and limitations in segmentation and volumetry. The material for the study was foreign and domestic literature sources of recent years. The sources were selected using the following keywords: liver, anatomy, liver segments, liver volumetry, transplantation and some others. A total of 50 sources were selected. The descriptive method of analysis was used. Liver segmentation and volumetry already allow solving a wide range of clinical problems, including preoperative planning of resections and transplants, assessment of the dynamics and effectiveness of treatment, as well as building prognostic models and training. The review presents the results of studies of the volumetric assessment of the functional reserve of an organ when planning operations and ways to increase it, discusses manual, semi-automatic and automatic methods of segmentation with their advantages and disadvantages. Particular emphasis is placed on the role of the development of segmentation and volumetry technologies in transplantology. In conclusion, unresolved problems are noted, which require improvement of visualization algorithms, consideration of anatomical variants in segmentation and liver volumetry with the fastest integration of artificial intelligence to improve the accuracy and speed of the analysis. Timely solution of a wide range of designated tasks will continue to contribute to the transformation of approaches in surgical hepatology, providing priority to safe and personalized.

1. Trefts E, Gannon M, Wasserman DH. The liver. Curr Biol. 2017;27(21):R1147-R1151

2. Pereskokov SV, Dmitriev AV, Groshilin VS i dr. Khirurgiya pecheni: ot istokov razvitiya do sovremennykh vozmozhnostey. Sovremennye problemy nauki i obrazovaniya. 2017;(5):170-170. In Russian

3. Juza RM, Pauli EM. Clinical and surgical anatomy of the liver: a review for clinicians. Clin Anat. 2014 Jul;27(5):764-769

4. Ivashchenko OV, Rijkhorst EJ, Ter Beek LC et al. A workflow for automated segmentation of the liver surface, hepatic vasculature and biliary tree anatomy from multiphase MR images. MagnReson Imaging. 2020;68:53-65

5. Srimani P, Saha A. Liver morphology: anatomical study about the outer aspects. Surg Radiol Anat. 2020;42(12):1425-1434

6. Alirr OI, Rahni AAA. Survey on Liver Tumour Resection Planning System: Steps, Techniques, and Parameters. J. Digit. Imaging. 2020;33:304-323

7. Jeong JG, Choi S, Kim YJ et al. Deep 3D attention CLSTM U-Net based automated liver segmentation and volumetry for the liver transplantation in abdominal CT volumes. Sci. Rep. 2022;12:6370

8. Ansari MY, Abdalla A, Ansari MY et al. Practical utility of liver segmentation methods in clinical surgeries and interventions. BMC Med. Imaging. 2022;22:97

9. Bhat M, Rabindranath M, Chara BS et al. Artificial intelligence, machine learning, and deep learning in liver transplantation. J. Hepatol. 2023;78:1216-1233

10. Gotra A, Sivakumaran L, Chartrand G, et al. Liver segmentation: Indications, techniques and future directions. Insights Imaging. 2017;8:377-392

11. Senthilvelan J, Jamshidi N. A pipeline for automated deep learning liver segmentation (PADLLS) from contrast enhanced CT exams. Sci. Rep. 2022;12:15794. https://doi.org/10.1038/s41598-022-20108-8

12. Bonnel F, Duparc F. Historical anatomy of hepatic segmentation: about 250 livers corrosions by Rapp (1953) and Couinaud (1953) in the Conserva-tory of Anatomy in Montpellier. Surg Radiol Anat. 2020;42(12):1407-1420. https://doi.org/10.1007/s00276-020-02596-3

13. Parhisenko YuA, Vorontsov AK, Kalashnik RS i dr. Istoriya razvitiya khirurgicheskoy anatomii organov gepatopankreatobiliarnoy zony. Vestnik Smolenskoy gosudarstvennoy meditsinskoy akademii. 2016;(4):172-181. In Russian

14. Couinaud C. Lobesetsegmentshepatigues: notessurarchitectureanatomigueetchirurgicaledufoie. Presse Med. 1954:105-310

15. Garg S, Kumar KH, Sahni D et al. Anatomy of the hepatic arteries and their extrahepatic branches in the human liver: a cadaveric study. Ann Anat. 2020;227:151409. https://doi.org/10.1016/j.aanat.2019.07.010

16. Abdalla EK, Vauthey JN, Couinaud C. The caudate lobe of the liver: implications of embryology and anatomy for surgery. Surg Oncol Clin N Am. 2002;11(4):835-848. https://doi.org/10.1016/s1055-3207(02)00035-2

17. Sagoo MG, Aland RC, Gosden E. Morphology and morphometry of the caudate lobe of the liver in two populations. Anat Sci Int. 2018;93(1):48-57. https://doi.org/10.1007/s12565-016-0365-7

18. Shruthy KM, Sudhakaran R. Vascular Anatomy of Segment IV of the Liver in Live Liver Donors. Cureus. 2023;15(9):e46281. https://doi.org/10.7759/cureus.46281

19. Bageacu S, Abdelaal A, Ficarelli S et al. Anatomy of the right liver lobe: a surgical analysis in 124 consecutive living donors. Clin Transplant. 2011;25(4):E447-54. https://doi.org/10.1111/j.1399-0012.2011.01466.x

20. Couinaud C. Erreur dans le diagnostic topographique des lésionshépatiques [Errors in the topographic diagnosis of liver diseases]. Ann Chir. 2002;127(6):418-30. French. https://doi.org/10.1016/s0003-3944(02)00802-7

21. Goldsmith NA, Woodburne RT. The surgical anatomy pertaining to liver resection. Surgery, gynecology & obstetrics. 1957;105(3):310

22. Qin W, Wang L, Hu B et al. Anatomical sites (Takasaki's segmentation) predicts the recurrence-free survival of hepatocellular carcinoma. BMC Surg. 2021;21(1):278. https://doi.org/10.1186/s12893-021-01275-3

23. Belgihiti, J, Clavien PA et al. The Brisbane 2000 terminology of liver anatomy and resections. HPB. 2000;2:333-339

24. Kobayashi T et al. Study on the segmentation of the right anterior sector of the liver. Surgery. 2017;161(6):1536-1542

25. Bismuth H. Revisiting liver anatomy and terminology of hepatectomies. Ann Surg. 2013;257:383-386

26. Wei D, Jiang Y, Zhou X et al. A Review of Advancements and Challenges in Liver Segmentation. J Imaging. 2024;10(8):202. https://doi.org/10.3390/jimaging10080202

27. Oh N, Kim JH, Rhu J et al. Automated 3D liver segmentation from hepatobiliary phase MRI for enhanced preoperative planning. Sci Rep. 2023;13(1):17605. https://doi.org/10.1038/s41598-023-44736-w

28. Oliveira DA, Feitosa RQ, Correia MM. Segmentation of liver, its vessels and lesions from CT images for surgical planning. Biomed Eng Online. 2011;10:30. https://doi.org/10.1186/1475-925X-10-30

29. Strunk H, Stuckmann G, Textor J et al. Limitations and pitfalls of Couinaud's segmentation of the liver in transaxial Imaging. EurRadiol. 2003;13(11):2472-2482. https://doi.org/10.1007/s00330-003-1885-9

30. Paschold M, Huettl F, Kneist W et al. Local, semi-automatic, three-dimensional liver reconstruction or external provider? An analysis of performance and time expense. Langenbecks Arch Surg. 2020;405(2):173-179. https://doi.org/10.1007/s00423-020-01862-7

31. Le DC, Chinnasarn K, Chansangrat J et al. Semi-automatic liver segmentation based on probabilistic models and anatomical constraints. Sci Rep. 2021;11(1):6106. https://doi.org/10.1038/s41598-021-85436-7

32. Kavur AE, Gezer NS, Barış M et al. Comparison of semi-automatic and deep learning-based automatic methods for liver segmentation in living liver transplant donors. DiagnIntervRadiol. 2020;26(1):11-21. https://doi.org/10.5152/dir.2019-19025

33. Gross M, Huber S, Arora S et al. Automated MRI liver segmentation for anatomical segmentation, liver volumetry, and the extraction of radiomics. EurRadiol. 2024;34(8):5056-5065. https://doi.org/10.1007/s00330-023-10495-5

34. Fasel JH, Selle D, Evertsz CJ et al. Segmental anatomy of the liver: poor correlation with CT. Radiology. 1998;206(1):151-156. https://doi.org/ 10.1148/radiology.206.1.9423665

35. Heimann T, van Ginneken B, Styner MA et al. Comparison and evaluation of methods for liver segmentation from CT datasets. IEEE Trans Med Imaging. 2009;28(8):1251-1265. https://doi.org/10.1109/TMI.2009.2013851

36. Huynh HT, Karademir I, Oto A et al. Computerized liver volumetry on MRI by using 3D geodesic active contour segmentation. AJR Am J Roent-genol. 2014;202(1):152-159. https://doi.org/10.2214/AJR.13.10812

37. Ferrero A, Vigano L, Polastri R et al. Postoperative liver dysfunction and future remnant liver: where is the limit? Results of a prospective study. World J Surg. https://doi.org/10.1007/s00268-007-9123-2

38. Abdalla EK, Adam R, Bilchik AJ et al. Improving resectability of hepatic colorectal metastases: expert consensus statement. Ann Surg Oncol. 2006;13(10):1271-1280. https://doi.org/10.1245/s10434-006-9045-5

39. Abdalla EK. Portal vein embolization (prior to major hepatectomy) effects on regeneration, resectability, and outcome. J Surg Oncol. 2010;102(8):960-967. https://doi.org/10.1002/jso.21654

40. Castell DO, O'Brien KD, Muench H et al. Estimation of liver size by percussion in normal individuals. Ann Intern Med. 1969;70(6):1183-1189. https://doi.org/10.7326/0003-4819-70-6-1183

41. Vauthey JN, Chaoui A, Do KA et al. Standardized measurement of the future liver remnant prior to extended liver resection: methodology and clini-cal associations. Surgery. 2000;127(5):512-519. https://doi.org/10.1067/msy.2000.105294

42. Greenbaum LE, Ukomadu C, Tchorz JS. Clinical translation of liver regeneration therapies: A conceptual road map. BiochemPharmacol. 2020;175:113847. https://doi.org/10.1016/j.bcp.2020.113847

43. Leung U, Simpson AL, Araujo RL et al. Remnant growth rate after portal vein embolization is a good early predictor of post-hepatectomy liver fail-ure. J Am Coll Surg. 2014;219(4):620-630. doi: 10.1016/j.jamcollsurg.2014.04.022

44. Meier RP, Toso C, Terraz S et al. Improved liver function after portal vein embolization and an elective right hepatectomy. HPB (Oxford) 2015;17(11):1009-1018. https://doi.org/10.1111/hpb.12501

45. Hernandez-Alejandro R, Bertens KA, Pineda-Solis K et al. Can we improve the morbidity and mortality associated with the associating liver parti-tion with portal vein ligation for staged hepatectomy (ALPPS) procedure in the management of colorectal liver metastases? Surgery. 2015;157(2):194-201. https://doi.org/10.1016/j.surg.2014.08.041

46. Broering DC, Sterneck M, Rogiers X. Living donor liver transplantation. J Hepatol. 2003;38(1):S119-S135. https://doi.org/10.1016/S0168-8278(03)00009-6

47. Low HC, Da Costa M, Prabhakaran K et al. Impact of new legislation on presumed consent on organ donation on liver transplant in Singapore: a preliminary analysis. Transplantation. 2006;82(9):1234-1237. https://doi.org/10.1097/01.tp.0000236720.66204.16

48. Klinicheskie rekomendatsii. Transplantatsiya pecheni, nalichie transplantirovannoy pecheni, otmiranie i ottorzhenie transplantata pecheni. Ob-shcherossiyskaya obshchestvennaya organizatsiya transplantologov «Rossiyskoe transplantologicheskoe obshchestvo». 2020. – S. 95. In Russian

49. Kiuchi T, Tanaka K, Ito T, et al. Small-for-size graft in living donor liver transplantation: how far should we go? Liver Transpl. 2003;9(9):S29-S35. https://doi.org/10.1053/jlts.2003.50198

50. Fan ST, Lo CM, Liu CL et al. Safety of donors in live donor liver transplantation using right lobe grafts. ArchSurg. 2000;135(3):336-340. https://doi.org/10.1001/archsurg.135.3.336