Shwetha K and Dakshayani K R: Study on branching pattern of segmental branches of splenic artery in human cadaveric spleens by dissection method


Introduction

The spleen is a highly vascular and friable organ. It is the largest secondary lymphoid organ, which contains 25% of the body lymphoid tissue and has both haematological and immunological functions. Spleen is supplied by splenic artery which is the largest branch of coeliac trunk.1 It traverses through the lienorenal ligament to reach near the hilum of the spleen, where it divides into two or three primary branches, each of which is subdivided mostly into two or four secondary branches. Moreover, a superior polar arteries and inferior polar arteries are given from splenic trunk or from one of its primary branches, which goes to the poles of the spleen, without entering the hilum. It is called as superior and inferior polar branches. The human spleen is divided accordingly into two or three main segments. Each main segment is also divided usually into two to four less constant secondary segments. The segments of spleen are separated by a definite avascular plane.

The partial removal of the spleen is possible, as the spleen is divided into segments, separated by fibrous septa and each segment is supplied by its own main artery.2 The presence of splenic segmentation could be attributed to its development or to the terminal division of the artery.

Better anatomical knowledge about segmental distribution of splenic artery and its variations are important for the partial removal of the organ. So, keeping the applied aspect and clinical significance of segmental branches of splenic artery and to add more knowledge to the existing one, the present study was undertaken to study the segmental branches of splenic artery which divide the spleen into various segments, its pattern of distribution and also to find out any inter-segmental arterial anastomosis by dissection method.

Aims and Objectives

To study the branching pattern of the segmental branches of splenic artery and to find out if there is any the anastomosis between the segmental branches.

Materials and Methods

The present study is conducted on 79 Human cadaver spleens, irrespective of their age and sex, fixed in 10% formalin solution, collected from the department of Anatomy and Forensic Medicine, Mysore Medical College and Research Institute.

The gross dissection was done by following the guide lines of Cunningham’s Manual. The spleen was identified and freed from the posterior abdominal wall and stomach by cutting through the gastrosplenic and lienorenal ligaments. The splenic artery was cut about 10 cm proximal to hilum of spleen, then the spleen was removed. The fascia and fat was cleared at the hilum to expose the segmental branches of the splenic artery. Firstly, the primary segmental branches of the splenic artery and its branching patterns were identified and noted, then by removing the parenchyma along the primary branches by piecemeal dissection the secondary branches and also inter segmental arterial anastomosis if any were noted.

Results

Two primary segmental branches were seen in 56 (70.9%) specimens, three primary segmental branches were seen in 19 (24.1%) specimens and four primary segmental branches were seen in 4 (5.1%) specimens.

Superior polar artery was present in 18 (22.8%) specimens and inferior polar artery was present in 32 (40.5%) specimens and both superior and inferior polar artery was seen in 5 (6.3%) specimens.

Superior polar artery arising from main trunk was present in 12 (67%) specimens and superior polar artery arising from primary branch seen in 6 (33%) specimens.

Inferior polar artery was seen arising from main trunk in 15 (47%) specimens, from left gastroepiploic artery in 9 (28%) specimens and from primary branch in 8 (25%) specimens.

Anastomosis between the primary segmental branches were seen in 11 (13.9%) specimens.

The extra-parenchymal anastomosis of primary segmental branches was seen in 5 (6.3%) specimens. The intra-parenchymal anastomosis was seen in 3 (3.7%) and sub-capsular type of anastomosis was seen in 3 (3.7%) specimens.

The distributive type of branching pattern was present in 50 (63.3%) specimens. The marginal type of branching pattern was present in 29 (36.7%) specimens.

Figure 1

Extra-parenchymal anastomosis between superior and inferior primary branches

EP. Anas. – Extra Parenchymal Anastomosis)

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/7ac70c50-1835-496e-8853-fef33127ed56/image/797f171b-c57a-4dcc-8307-38b351eadfd9-uimage.png

Figure 2

Intra-parenchymal anastomosis between superior primary branch and superior polar artery

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/7ac70c50-1835-496e-8853-fef33127ed56/image/04e13714-fe9a-42f7-af0a-fb5636ab1fe9-uimage.png

Figure 3

Sub-capsular type of anastomosis between superior and inferior primary branches

SC. Anas. – Sub capsular Anastomosis)

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/7ac70c50-1835-496e-8853-fef33127ed56/image/9ecabbb3-f9eb-41c1-b087-c861204a84e1-uimage.png

Figure 4

Distributive type of branching pattern

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/7ac70c50-1835-496e-8853-fef33127ed56/image/e515d565-5377-4fe3-8850-4aa3dec71e18-uimage.png

Figure 5

Marginal type of branching pattern

https://typeset-prod-media-server.s3.amazonaws.com/article_uploads/7ac70c50-1835-496e-8853-fef33127ed56/image/e4a9ad0a-2ab7-44f9-89f6-b55a14c79a4e-uimage.png

Table 1

Number of primary segmental branches of splenic artery

S. No.

Primary segmental branches

Number of specimens

Percentage (%)

1

One

Nil

0

2

Two

56

70.9

3

Three

19

24.1

4

Four

4

5.1

5

Total

79

100

Table 2

Types of anastomosis

Types of anastomosis

Number of specimen

Percentage (%)

None

68

86.3

Extra-parenchymal

5

6.3

Intra-parenchymal

3

3.7

Sub-capsular

3

3.7

Total

79

100.0

Table 3

Comparison of number of primary segmental branches of splenic artery with the previous studies

Author

Number of specimens studied

Number of primary segmental branches

2

3

4

Gupta CD et al. (1976)3

50

84%

16%

-

Mikhail Y et al. (1979)4

25

77%

23%

-

Katrisis E et al. (1982)5

70

88.7%

14.3%

-

Mandarin LCA (1983)6 [6]

25

68.2%

10.6%

4.5%

Garcia PJA (1988)7

181

92.82%

7.18%

-

Sow ML (1991)8

32

84%

16%

-

Silva LFA (2010)9

-

93.34%

6.66%

-

Chaware PN et al. (2012)10

-

85.58%

14.42%

-

Swamy VL et al. (2013)11

60

66%

17%

17%

Londhe SR et al. (2013)12

50

90%

10%

-

Present study

79

70.9%

24.1%

5.1%

Table 4

Comparison of polar arteries with the previous studies

Author

Polar artery

Superior

Inferior

Both

Present Study

22.8%

40.5%

6.3%

Mikhail Y et al4

18%

50%

12%

Garcia PA et al7

29.28%

44.75%

10.49%

Chaware PN et al10

28.82%

42.34%

11.7%

Swamy VL et al11

41.6%

25%

16.6%

Londhe SR et al12

32%

56%

24%

Table 5

The comparison of anastomosis between segmental branches with the previous studies

Author

Observation

Present study

13.9%

Gupta CD et al3

No anastomosis

Garcia PJA et al7

19.89%

Mandarim LCA et al6

16.7%

Chaware PN et al10

1.80%

Table 6

Comparison of types of anastomosis with the previous studies

Author

Type of anastomosis

Extra-parenchymal

Intra-parenchyma

Sub-capsular

Present study

6.3%

3.7%

3.7%

Sow ML et al.8

9%

32%

-

Holibkova A et al.13

15%

45%

8%

Table 7

The comparison of branching pattern with the previous studies

Author

Branching Pattern

Distributive type

Marginal type

Present study

63.3%

36.7%

Michels NA et al.14

70%

30%

Holibkova A et al.13

80%

20%

Charles Brunicardi F et al.15

70%

30%

Discussion

Spleen is supplied by splenic artery, which terminates at the hilum by dividing into 2 or 3 terminal branches. These are named as superior, middle and inferior primary branches. These branches supply a particular part of the spleen which is separated by an avascular plane. Thus, these branches divide the spleen into definite arterial segments. So these arteries can be considered as the primary segmental branches.5 In the present study two primary branches were seen in 56 (70.9%) specimens, three in 19 (24.1%) specimens and four in 4 (5.1%) specimens. Other studies showed only 2 to 3 primary branches. In this study we have observed 2 to 4 primary branches. The comparison of number of primary branches with the previous studies is given in Table 3.

In some spleens, a branch arising from splenic artery itself or one of its primary branch which does not pierce the hilum, but goes to the poles of spleen. These are known as superior and inferior polar arteries. These arteries also supply a particular segment of spleen, which can be considered as the polar segments.16 In our study we observed superior polar artery was present in 18(22.8%) specimens and inferior polar artery was present in 32 (40.5%) specimens and both superior and inferior polar artery was seen in 5 (6.3%) specimens. The comparison between other studies is given in Table 4.

Superior polar arteries arising from main trunk was present in 12 (67%) specimens and superior polar arteries arising from primary branch were seen in 6 (33%) specimens. Inferior polar artery was seen arising from main trunk in 15 (47%) specimens, from left gastroepiploic artery in 9 (28%) specimens and from primary branch in 8 (25%) specimens.

Katrisis E et al5 in their study noted that, the polar arteries arise either from main trunk or primary branch. Silva LFA et al9 observed 16% arising from main trunk and 20% arising from terminal branches. Swamy VL et al11 noted all polar arteries arising from main trunk only.

The spleen is divided into segments; each segment is supplied by its own segmental branches. These segments are separated by a definite avascular plane. But rarely there may be an inter-segmental anastomosis. In the present study, anastomosis between the primary segmental branches seen in 11 (13.9%) specimens. The comparison of anastomosis between segmental branches with previous studies is given in Table 5.

The inter-segmental anastomosis can be of three types.

  1. Extra parenchymal Anastomosis.

  2. Intra parenchymal anastomosis.

  3. Sub capsular anastomosis.

In the present study we observed, the extra-parenchymal anastomosis of primary segmental branches were seen in 5 (6.3%) specimens, the intra parenchymal anastomosis was seen in 3 (3.7%) specimens and sub capsular type of anastomosis was seen in 3 (3.7%) specimens. Comparison of type of anastomosis with the previous studies is given in Table 6.

Based on terminal branching pattern, the splenic artery pedicle can be classified into two types.

  1. Distributive type where the splenic artery divides away from the hilum of the spleen with long terminal branches that enters through the hilum.

  2. Marginal type where the artery divides at the hilum with short terminal branches.

In the present study we observed, the distributive type of branching pattern was present in 50(63.3%) specimens and the marginal type of branching pattern was present in 29(36.7%) specimens.

A study conducted by Henschen et al.17 classified three types of pattern and observed, short distribution in 10%, long distribution in 40% and marginal type in 46%. The comparison of present study with previous studies is given in Table 7.

Conclusion

The spleen is a highly vascular and friable organ. It is the largest of secondary lymphoid organ, which contains 25% of the body’s lymphoid tissue and has both haematological and immunological functions. Total splenectomy is commonly done after a splenic injury, which leads to decrease in the immunity and predisposes the normal host to overwhelming life threatening infections and also creates an altered haematological picture. To overcome this, partial splenectomy can be done by ligating a particular segmental branch of splenic artery.

The partial removal of the spleen is possible, as the spleen is divided into segments, separated by fibrous septa and each segment is supplied by its own main artery. The presence of splenic segmentation could be attributed to its development or to the terminal division of the artery. Better anatomical knowledge about segmental distribution of splenic artery and its variations are important for the partial removal of the organ.

Source of Funding

None.

Conflicts of Interest

None.

References

1 

S Standring The Anatomical Basis of Clinical PracticeGray’s Anatomy39th editionChurchill Livingstone ElsevierEdinburg2008123945

2 

E Kyber Uber die Milz des Menschen and einiger sangetiereArch Microsk Anat Entw Mech1870654070

3 

CD Gupta SC Gupta AK Arora SP Jeya Vascular segments in human spleenJ Anat197612136136

4 

Y Mikhail R Kamel NNY Nawar MFM Rafla Observations on the mode of termination and parenchymal distribution of the splenic artery with evidence of splenic lobation and segmentationJ Anat197912822538

5 

E Katritsis A Parashos N Papadopoulos Arterial Segmentation of the Human Spleen by Post-Mortem Angiograms and Corrosion-CastsAngiology19823311720710.1177/000331978203301104

6 

SR Londhe Study of vascular pattern in human spleen by carrion cast methodAl Ameen J Med Sci2013621679

7 

JA Garcia-Porrero A Lemes Arterial Segmentation and Subsegmentation in the Human SpleenCells Tissues Organs198813142768310.1159/000146529

8 

ML Sow A Dia T Ouedraogo Anatomic basis for conservative surgery of the spleenSurg Radiol Anat199113281710.1007/bf01623878

9 

LFA Silva Morfometric study of arterial branching of the spleen compared to radiological studyRev Col Bras Cir20113831815

10 

PN Chaware SM Belsare YR Kulkarni SV Pandit JM Ughade Variational anatomy of the segmental branches of the splenic arteryJCDR2012633368

11 

VLI Swamy D Suseelamma SD Jadhav ZR Balbhim NP Mithil K Chaitanya Study of prehilar branches of splenic artery by dissection methodInt J Med Res Health Sci201323620310.5958/j.2319-5886.2.3.109

12 

LCA Mandarim FJ Sampaio MA Passos Vascular segmentation of the spleen in the new born infants. Anatomical support for partial resectionJ Chir (Paris)19831208-94713

13 

A Holibkova L Machalek D Houserkova V Ruzieka A contribution to the types of branching and anastomosis of the splenic artery in the human spleenBiomedical Papers199814114952

14 

FC Brunicardi Schwartz’s Principles of Surgery8th editionMcGraw-Hill Companies Inc20051298

15 

NA Michels The variational anatomy of the spleen and splenic arteryAm J Anat1942701217210.1002/aja.1000700103

16 

HP Redmond JM Redmond BP Rooney JP Duignan DJ Bouchier-Hayes Surgical anatomy of the human spleenBr J Surg198976219820110.1002/bjs.1800760230

17 

C Henschen Die chirurgischen Anatomie der MilzgefisseSchweiz Med Wochenschr19285816170



jats-html.xsl

© This is an open access article distributed under the terms of the Creative Commons Attribution License (creativecommons.org) which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


  • Article highlights
  • Article tables
  • Article images

Article History

Received : 16-02-2021

Accepted : 23-02-2021

Available online : 12-04-2021


View Article

PDF File   Full Text Article


Copyright permission

Get article permission for commercial use

Downlaod

PDF File   XML File   ePub File


Digital Object Identifier (DOI)

Article DOI

https://doi.org/10.18231/j.ijcap.2021.007


Article Metrics






Article Access statistics

Viewed: 100

PDF Downloaded: 58