NJCA
  • Users Online: 104
  • Print this page
  • Email this page
  • Email this page
  • Facebook
  • Twitter


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2019  |  Volume : 8  |  Issue : 1  |  Page : 22-26

Normal anatomy of porta hepatis—A cadaveric study


Department of Anatomy, Belagavi Institute of Medical Sciences, Belagavi, Karnataka, India

Date of Web Publication7-Sep-2020

Correspondence Address:
Umesh K Kulkarni
Department of Anatomy, Belagavi Institute of Medical Sciences, Belagavi, Karnataka
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.1055/s-0039-1688545

Rights and Permissions
  Abstract 


Background and Aim Porta hepatis (PH) of the liver acts as a gateway for exit and entry of important structures like portal vein, hepatic artery, and hepatic duct. Having knowledge of variations about the dimensions and structures at PH becomes important to avoid complications during surgical and radiological interventions. Our study aims to observe the dimensions of PH and also the number, arrangement, and variations of structures passing through PH.
Materials and Methods Fifty adult cadaveric human livers which were preserved in formalin were studied. Transverse diameter, anteroposterior diameter, and circumference of PH were measured using vernier calipers, measuring scale, and thread. PH was carefully dissected to study the number, arrangement, and combination of arteries, veins, and ducts at PH.
Results The mean transverse diameter, anteroposterior diameter, and total circumference of PH was 3.17 ± 0.50, 1.68 ± 0.36, and 10.46 ± 1.415 cm, respectively. Eighteen specimens showed presence of two arteries, two veins, and one duct at PH. Maximum number of arteries, veins, and ducts passing through PH were 5, 4, and 1, respectively. The ducts were anterior, arteries in the middle, and veins were posterior in PH of all the livers.
Conclusion The variations observed in our study will be of great importance to anatomists, surgeons, and radiologists.

Keywords: porta hepatis, portal vein, hepatic artery, hepatic duct


How to cite this article:
Neginhal DD, Kulkarni UK. Normal anatomy of porta hepatis—A cadaveric study. Natl J Clin Anat 2019;8:22-6

How to cite this URL:
Neginhal DD, Kulkarni UK. Normal anatomy of porta hepatis—A cadaveric study. Natl J Clin Anat [serial online] 2019 [cited 2021 Jan 21];8:22-6. Available from: http://www.njca.info/text.asp?2019/8/1/22/294464




  Introduction Top


The liver is the largest gland and the most important organ in human body. It also performs an astonishingly large number of tasks that impact the whole body system. As the liver is involved in majority of the metabolic activities in the body, it is more likely to get affected by various pathological conditions.

Porta hepatis (PH) is a transverse nonperitoneal fissure on the inferior surface which acts as a gateway of the liver. It extends from the neck of the gall bladder to the fissure for ligamentum teres and venosum, and intervenes between the quadrate lobe in the front and caudate process at the back. Although PH is nonperitoneal, its margins give attachment to lesser omentum. Hepatic artery with autonomic plexus around it and the portal vein (PV) enter the liver through PH. Lymphatics and the hepatic duct emerges out of the liver through PH.

PH transmits important neurovascular structures and hence it acquires great importance while carrying out clinical procedures like liver transplant, surgical interventions, and diagnostic radiological procedures which can be associated with complications. The “complex anatomic architecture” of the vascular and biliary structures at the PH makes it a surgically challenging area.[1] Hence, a surgeon requires detailed knowledge of the normal anatomy of PH and structures related to it.

The present study aims in studying the dimensions, numerical variations, and arrangement of structures in PH. These findings will be of significance for anatomists, surgeons operating on this region, and radiologists to avoid iatrogenic complications.


  Materials and Methods Top


The study was conducted at the Belagavi Institute of Medical Sciences, Belgaum, on 50 adult cadaveric human livers preserved in formalin of unknown sex. Ethical approval was taken from the institutional ethical committee prior to the commencement of the study.

Specimens with any surface anomalies and pathologies were excluded from the study. On inferior surface PH was identified and the transverse diameter and anteroposterior diameter were measured using sliding vernier calipers. Total circumference was measured with a thread and confirmed with a measuring scale (see [Figure 1]). Average of three measurements was recorded. The PH was carefully dissected and studied for number, arrangement, and combination of structures [Figure 2],[Figure 3],[Figure 4],[Figure 5],[Figure 6].
Figure 1: Line diagram of the inferior surface of liver with porta hepatis showing the various diameters measured. Abbreviations: AP, anteroposterior diameter; C, circumference represented by dotted line; CL, caudate lobe; GB, gallbladder; IVC, inferior vena cava; LL, left lobe, QL, quadrate lobe; RL, right lobe; TD, transverse diameter.

Click here to view
Figure 2: Porta hepatis with two arteries, two veins, and one duct.

Click here to view
Figure 3: Porta hepatis with four veins.

Click here to view
Figure 4: Porta hepatis with five arteries, two veins, and one duct.

Click here to view
Figure 5: Porta hepatis with three arteries, two veins, and one duct.

Click here to view
Figure 6: Porta hepatis with four arteries, one vein, and one duct. Abbreviations: A, artery; D, duct; HA, hepatic artery; PV, portal vein; V, vein.

Click here to view



  Results Top


In the present study, the transverse diameter and anteroposterior diameter of PH ranged from 2.4 to 4.5 cm to 1.0 to 2.6 cm. The mean ± standard deviation (SD) for transverse diameter and anteroposterior diameter were 3.17 ± 0.50 and 1.68 ± 0.36 cm, respectively. The minimum total circumference measured was 7.5 cm and the maximum was 12.8 cm with a mean ± SD of 10.46 ± 1.415 cm. The measurements are shown in [Table 1].
Table 1: Dimensions of porta hepatis

Click here to view


[Table 2] shows various combinations of the structures passing through PH and their frequency of occurrence. The common combination in our study was two veins, two arteries, and one duct which were seen in 36% of specimen followed by two veins, three arteries, and one duct in 22% and one vein, two arteries, and one duct in 20% of specimens.
Table 2: Various combinations of structures passing through porta hepatis and their frequency of occurrence

Click here to view


The number of structures varied from one to five for arteries; 56% of specimens showed two arteries and one to four veins,72% of specimens showed two veins, and 100% of specimens showed only one duct ,[Figure 2],[Figure 3],[Figure 4],[Figure 5],[Figure 6]. Details for the number of structures passing through PH and their frequency of their occurrence are shown in [Table 3].
Table 3: Number of each structures passing through porta hepatis and frequency of their occurrence

Click here to view


The arrangement of structures in the PH was constant. The ducts were anterior, arteries in the middle, and veins were posterior in PH of all the livers.


  Discussion Top


PH acts as the gateway of liver through which important structures entry and exit, namely, the PV, hepatic artery, and hepatic duct. The anatomical arrangement and dimensions of these structures is very important for surgeons and radiologists. Common complications of surgeries around the liver may be vascular or nonvascular like biliary peritonitis or biliary stricture following bile duct injury, vascular complications like pseudoaneurysms, hematoma, arterial dissections, or transections. Some of the minimal invasive procedures like percutaneous drainage catheter placement, balloon dilatation, stenting, and coil embolization also lead to complications.[2]

In this study, 50 formalin preserved livers were studied for the dimensions of PH which included the transverse and anteroposterior diameters and the circumference which showed a wide variation. The number of structures and their arrangement with various combinations was observed, the most common combination observed was of two veins, two arteries, and one duct which were seen in 36% of specimens [Figure 2]. As shown in [Table 4], our findings correlates with other studies.[3],[4] PV showed bifurcation in 72% of specimen which was highest followed by single vein in 26% and maximum number of veins was four which was seen in 2% of specimen [Figure 2]. Trifurcation of vein was not observed in the present study.
Table 4: Comparison of observations of the present study with figures quoted in similar studies

Click here to view


As a result of advances in noninvasive cross-sectional imaging techniques and improvements in multidetector computed tomography, three-dimensional imaging has become possible, due to which the abdominal venous anatomic variations and anomalies are commonly detected in routine examinations.[5] Anatomical variations of the PV are common, and extensive study has been conducted to understand the varying branching patterns of the PV and few studies have also reported about the absence of PV branching.[6],[7],[8]

Advancements in surgical and interventional procedures of the liver increase the significance of PV variations. Anatomic PV variations play a critical role in evaluations before surgical interventions, transplantations, and interventional procedure of the liver.[9]

Hepatic artery proper is a branch of the common hepatic artery, it passes through the right free margin of the lesser omentum and enters the PH where it divides into right and left branch. Number of arteries found in PH in the present study was from one to five; two arteries were seen in 56% of specimen and three arteries in 26%. Five arteries were seen in 2% of the liver [Figure 4]. Common variations reported about the hepatic artery is about its branching pattern and its accessory arteries.[10],[11],[12] A study has also reported about the anomalous variation of the origin of the right and left hepatic artery.[13]

A surgeon should have immense knowledge about the variants of the hepatic artery to reduce iatrogenic complications in hepatobiliary surgeries, surgical management of liver trauma, aneurysm of hepatic artery, hepatic arterial infusion chemotherapy, liver transplant surgery, and other such surgeries of this complex anatomic region.[14]

In the present study, single hepatic duct was observed in all the livers, and hepatic duct showed no branching [Figure 2],[Figure 3],[Figure 4],[Figure 5],[Figure 6]. As mentioned in Gray’s text book of anatomy, the main right and left hepatic ducts unite near the right end of PH as the common hepatic duct and passes downwards within the right free margin of the lesser omentum.[15] However, in our study, we have not observed the right and left extrahepatic part of the hepatic duct. Our finding correlates with similar observations, single duct was observed in 79.7 and 76% of liver specimens, respectively.[3],[4] Anatomical and radiological studies have shown the presence of accessory hepatic ducts at different levels of the biliary tree and also observed the absence of right and left hepatic ducts.[16],[17],[18],[19] Because of these anatomic variations, it becomes very much important to have knowledge about these hepatic duct variations of accessory hepatic ducts and also about their position, especially during laparoscopic cholecystectomies, as incidence of bile duct injuries is as twice as high when compared with open cholecystectomies.[20]

Biliary anatomy and its common and uncommon variations are of considerable clinical significance when performing living donor transplantations, radiological interventions in hepatobiliary system, laparoscopic cholecystectomy, and liver resection (hepatectomy, segmentectomy). Magnetic resonance choliangiopancreatography has become the modality of choice for noninvasive evaluation of abnormalities of the biliary tract.


  Conclusion Top


The findings in this study will help anatomists, radiologists, and surgeons to understand the variations of dimensions, number, and arrangement of structures at PH.

Conflict of Interest

None.



 
  References Top

1.
Tirumani SH, Shanbhogue AK, Vikram R, Prasad SR, Menias CO. Imaging of the porta hepatis: spectrum of disease. Radiographics 2014;34(1):73-92  Back to cited text no. 1
    
2.
Covey AM, Brody LA, Getrajdman GI, Sofocleous CT, Brown KT. Incidence, patterns, and clinical relevance of variant portal vein anatomy. AJR Am J Roentgenol 2004;183(4):1055-1064  Back to cited text no. 2
    
3.
Sapna M, Shetty SD, Nayak S. A study on the number and arrangement of the structures passing through the porta hepatis in South Indian population. Int J Morphol 2015;33(1):164-168  Back to cited text no. 3
    
4.
Gupta D, Sharma P, Gandotra A. Porta hepatis in normal liver. IJBAR 2017;8(3):121-125  Back to cited text no. 4
    
5.
Calhoun PS, Kuszyk BS, Heath DG, Carley JC, Fishman EK. Three-dimensional volume rendering of spiral CT data: theory and method. Radiographics 1999;19(3):745-764  Back to cited text no. 5
    
6.
Koq Z, Oguzkurt L, Ulusan S. Portal vein variations: clinical implications and frequencies in routine abdominal multidetector CT. Diagn Interv Radiol 2007;13(2):75-80  Back to cited text no. 6
    
7.
Kouadio EK, Bessayah A, Valette PJ, et al. Anatomic variation: absence of portal vein bifurcation. Surg Radiol Anat 2011;33(5):459-463  Back to cited text no. 7
    
8.
Chaib E. Absence of bifurcation of the portal vein. Surg Radiol Anat 2009;31(5):389-392  Back to cited text no. 8
    
9.
Erbay N, Raptopoulos V, Pomfret EA, Kamel IR, Kruskal JB. Living donor liver transplantation in adults: vascular variants important in surgical planning for donors and recipients. AJR Am J Roentgenol 2003;181(1):109-114  Back to cited text no. 9
    
10.
Kamath BK. A study of variant hepatic arterial anatomy and its relevance in current surgical practice. Int J Anat Res. 2015;3(1):947-953  Back to cited text no. 10
    
11.
Pujahari AK. Problem of a rare anomalous hepatic artery during Whipple procedure. Saudi J Gastroenterol 2010;16(2):122-123  Back to cited text no. 11
    
12.
Covey AM, Brody LA, Maluccio MA, Getrajdman GI, Brown KT. Variant hepatic arterial anatomy revisited: digital subtraction angiography performed in 600 patients. Radiology 2002;224(2):542-547  Back to cited text no. 12
    
13.
Bhardwaj N. Anomalous origins of hepatic artery and its significance for hepatobiliary surgery. J Anat Soc India 2010;59(2):173-176  Back to cited text no. 13
    
14.
Sehgal G, Srivastava AK, Sharma PK, Kumar N, Singh R. Variations of extrahepatic segments of hepatic arteries: a multislice computed angiography study. IJSRP 2013;3:1-8  Back to cited text no. 14
    
15.
Standring S, ed. Gray’s Anatomy: The Anatomical Basis of Clinical Practice. 40th ed. Philadelphia: Churchill Livingstone Elsevier; 2008:1178  Back to cited text no. 15
    
16.
Mariolis-Sapsakos T, Kalles V, Papatheodorou K, et al. Anatomic variations of the right hepatic duct: results and surgical implications from a cadaveric study. Anat Res Int 2012;2012:838179  Back to cited text no. 16
    
17.
Khayat MF, Al-Amoodi MS, Aldaqal SM, Sibiany A. Abnormal anatomical variations of extra-hepatic biliary tract, and their relation to biliary tract injuries and stones formation. Gastroenterol Res 2014;7(1):12-16  Back to cited text no. 17
    
18.
Du$unceli E, Erden A, Erden I. Anatomic variations of the bile ducts: MRCP findings [in Turkish]. Tani Girisim Radyol 2004;10(4):296-303  Back to cited text no. 18
    
19.
Ohkubo M, Nagino M, Kamiya J, et al. Surgical anatomy of the bile ducts at the hepatic hilum as applied to living donor liver transplantation. Ann Surg 2004;239(1):82-86  Back to cited text no. 19
    
20.
Devi KP. The study of variations of extra hepatic biliary apparatus. IOSR-JDMS. 2013;5(5):25-31  Back to cited text no. 20
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Materials and Me...
Results
Discussion
Conclusion
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed116    
    Printed12    
    Emailed0    
    PDF Downloaded17    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]