Origin of inferior phrenic arteries in the celiac trunk / Origen de las arterias frenicas inferiores en el tronco celiaco.
SUMMARY: The knowledge of the arterial anatomic variations is very important for the clinical, radiological and surgical diagnosis. Regarding inferior phrenic arteries, which irrigate the diaphragm, it is known that they vary in relation to their origin. The purpose of the present study is to verify these variations. The abdominal cavity of eighty-nine adult cadavers of both sexes was dissected, of which 69 fixed in 10% formalin solution and 20 non-fixed. The fixed cadavers were dissected in Laboratories of Anatomy of the Federal University of Sao Paulo (UNIFESP-EPM), the Santo Amaro University (UNISA) and Lusiadas de Santos University (UNILUS). The nonfixed cadavers were dissected from the Death Verification Service of the city of Sao Paulo (USP) and from the UNIFESP Brazil. After exposure of the celiac axis, we analyzed the possible emission of inferior phrenic arteries from this vessel as well as site of origin. The results showed us the presence of inferior phrenic arteries in 31 (34.83%) among the 89 cadavers. In the remained 58 (65.17%), the celiac trunkhad not these branches. It was observed that in 19 (21.35%) out of the 89 cadavers the inferior phrenic artery originating at the left contour of the celiac axis, in five (5.62%) cadavers, the phrenic artery presented its origin at the right contour and seven (7.86%) presented two phrenic arteries of which five were independently originated from each side of the celiac trunk and two (2.25%) from one axis.
KEY WORDS: Anatomy; Phrenic artery; Celiac artery; Anatomical variation.
PETRELLA, S.; RODRIGUES, C. F. S.; SGROTT, E. A; FERNANDEZ. G. J. M.; MARQUES, S. R. & PRATES. J. C. Origen de las arterias frenicas inferiores en el tronco celiaco. Int. J. Morphol., 24(2):137-142, 2006.
RESUMEN: El conocimiento de las variaciones anatomicas arteriales es de gran importancia para los diagnosticos clinico, radiologico y quirurgico. Con relacion a las arterias frenicas inferiores que irrigan el diafragma, se tiene conocimiento que estas presentan variaciones referentes a su origen.
Disecamos la cavidad abdominal de 89 cadaveres adultos de ambos sexos, de los cuales 69 fueron fijados en solucion de formalina a 10%, y 20 no fijados. Los cadaveres fijados fueron disecados en los laboratorios de Anatomia de la Universidad Federal de Sao Paulo-UNIFESP, en la Universidad de Santo Amaro-UNISA, y en la Universidad Lusiadas de Santos, UNILUS. Los cadaveres no fijados fueron disecados en los Servicios de Verificacion de Obitos de la capital (USP y UNIFESP), Brasil. Se verifico la emision de arterias frenicas inferiores a partir del tronco celiaco y el lugar de origen de estas.
Los resultados obtenidos indicaron la presencia de arterias frenicas inferiores en 31 (34.83%) de los 89 cadaveres. En los otros 58 (65.17%) el tronco celiaco no emitio tal ramo. Tambien se verifico en 19 (21.35%) de los 89 cadaveres, la arteria frenica inferior con origen en el contorno izquierdo del tronco celiaco, en 5 (5.62%) esta presentaba su origen en el contorno derecho y en 7 (7.86%) emitia dos arterias frenicas, mientras que 5 de estas se originaban separadamente de cada lado del tronco celiaco y 2 (2.25%) de un unico tronco.
Estos resultados permiten considerar el origen de las arterias frenicas inferiores en el tronco celiaco como una variacion anatomica.
PALABRAS CLAVE: Anatomia; Arteria frenica; Arteria celiaca; Variacion anatomica.
Vascular variations are constantly observed in dissection of adult cadavers (Lipshutz, 1917).
The phrenic arteries as collateral branches in the aorta abdominal part had their origin in right and/or left anterior contour of this vessel (Anson & McVay, 1936), but it may also occur as branches originated directly from the celiac trunk, independently at the right and/or left sides or from a common trunk (Lipshutz).
In general, these accessory vessels, which supply the diaphragm, are of small caliber (Lipshutz; Michels, 1951; 1953b).
The purpose of this study was to analyze percentage of inferior phrenic arteries originating at the celiac trunk either in males or females, as well as the percentage of origin of these arteries in the left and/or right sides of the celiac trunk.
MATERIAL AND METHOD
Eighty-nine cadavers from the following Institutions were dissected: Death Verification Service of the Federal University of Sao Paulo (UNIFESP/EPM), Obituary Service of the city of Sao Paulo at the Medical University of Sao Paulo (USP) and Anatomy Laboratories of the Federal University of Sao Paulo (UNIFESP/EPM), Medical Sciences Faculty of the Lusiada University Center (UNILUS) and the Santo Amaro University (UNISA).
Sixty-nine cadavers were dissected and fixed in 10% formalin solution, their ages ranging from 21 to 82 years, of which 60 were males and 9 females.
Also, 20 non-fixed cadavers were dissected and maintained in a frigorific chamber, of which 12 were males and eight females, with ages ranging from 34 to 88 years. Dissections were performed during the necropsies in the following institutions: Death Verification Service of the city of Sao Paulo in the Medical Faculty of the Sao Paulo University and in the Death Verification Service of the Federal University of Sao Paulo
To dissect the celiac trunk in the fixed cadavers, pancreas was removed and its body sectioned or divided with the aid of scissor. In non-fixed cadavers, the celiac trunkwas reached by the omentum, opening the flaccid part of the lesser omentum. Ganglions and the nervous tissue of the celiac plexus, involving the initial segment of the celiac trunk, were withdrawn with the aid of a pincer and scissor to allow observing disposition of these inferior phrenic arteries at the celiac trunk.
After resection of subjacent tissues to the diaphragmatic crura and adhesion of tissues all along the median arcuate ligament, these structures were exposed allowing observation of its relationships with the celiac trunk.
Statistical Analysis (Siegel et al., 1976). To study the possible associations between sexes and the presence of inferior phrenic arteries at the celiac trunk, in a type 2 x 2 table, the Chi-square test for two independent samples was used.
The rejection level for the null hypothesis was fixed in a value smaller or equal to 0.05% (5%). When the calculated statistics did not present significance, NS was used to characterize it.
The results of the presence of inferior phrenic arteries in the celiac trunk, when compared between sexes, in 89 cadavers, are shown in the Table I.
Analysis of these results showed that the difference between sexes, in relation the presence of these structures was not statistically significantly.
In the cases where the celiac trunkhad no inferior phrenic arteries, no statistically significant difference between sexes was observed.
In 31 (34.83%) cadavers, the inferior phrenic arteries had their origin in the celiac trunk (Fig. 1), in contrast to what occurred when evaluating 58 cadavers (65.17%), in which the celiac trunk did show this collateral branch.
[FIGURE 1 OMITTED]
When the presence of the inferior phrenic arteries was analyzed in 31 cadavers, it was observed that 19 (61.29%) or 21.35% of the overall cadavers analyzed in the current study, presented a left phrenic artery (Fig.2) with its origin at the left contour of the celiac trunk, 5 (16.13%) or 5.62% of the total showing a right phrenic artery (Fig.3) with origin at the contour of right celiac trunk and 7 (22.58%) or 7.86% of total, both arteries of which 5 (16.13%) or 5.62% of the total had their origin independent of each side of the celiac trunk and in 2 (6.45%) or 2.25% of the total from one celiac trunk.
[FIGURES 2-3 OMITTED]
In our study, we observed that the inferior phrenic arteries might have their origin either side of the celiac trunk or in booth sides, in different ratios.
The presence of these arteries in the celiac trunk was observed in 31 (34.83%) of the 89 analyzed cadavers and the absence in 58 (65.17%) (Fig.1). These results led us to conclude that the phrenic arteries with presence in the celiac trunk are a type of variation.
These findings are not in accordance with Michels (1953a), who reported this finding 74% in 200 cadavers.
The phrenic origin in the left contour of the celiac trunk was observed in 19 (21.35%) of the 89 cadavers, similar to the results of Pick & Anson (1940), who reported to have found 34 (17%) out of 200 cadavers and it is not in accordance with Lipshutz who observed six (7.23%). On the other hand, in five cadavers we could observe one inferior phrenic artery, originating from the right contour of the celiac trunk, similar to those found by Lipshutz in three (3.61%) cases.
The two inferior phrenic arteries origining in the celiac trunk, as independent branches, were found in five (5.62%) cadavers, differing from Pick & Anson who reported 41 (20.5%) and are in agreement with Lipshutz, who observed five (6.02%). The common trunk found in two (2.25%) was similar to the percentage of 2.41% of Lisphutz and differing from the 25 (12.5%) found by Pick & Anson.
The knowledge of this type of variation shows that surgeons must be cautious to avoid unintentional sectioning of small caliper arteries, as it may occur during the celiac artery decompression in the compression syndrome of the celiac trunkby the median arcuate ligament.
Received : 14-10-2005 Accepted: 28-03-2006
Anson, B. J. & McVay, C.B. The topographical positions and the mutual relations of the visceral branches of the abdominal aorta. A study of 100 consecutive cadavers. Anat. Rec., 67:7-15, 1936.
Lipshutz, B. A composite study of the coeliac trunkartery. Am. Surg., 65:159-69, 1917.
Michels, N.A. The hepatic, cystic and retroduodenal arteries and their relations to the biliary ducts. Ann. Surg., 133:503-24, 1951.
Michels, N.A. Variational anatomy of the hepatic, cystic, and retroduodenal arteries. Am. Med. Assoc., 66:20-34, 1953a.
Michels, N. A. Collateral arterial pathways to the liver after ligation of the hepatic artery and removal of the celiac axis. Cancer, 6:708-24, 1953b.
Pick, J.W. & Anson, B. J. Inferior phrenic artery. Anat. Rec., 78:413-25, 1940.
Siegel, S. Estatistica nao parametrica(para as ciencias do comportamento). MacGraw-Hill, SaoPaulo, 1976.
* Selma Petrella; ** Celio Fernando de Sousa Rodriguez; *** Emerson Alexandre Sgrott; **** Geraldo Jose Medeiros Fernandes; **** Sergio Ricardo Marques; **** Jose Carlos Prates
* Arbovirus Division, Adolfo Lutz Institute, Sao Paulo, Brazil.
** Department of Morphology, Federal University of Alagoas, Brazil.
*** Descriptive and Topographic Anatomy Division, Vale do Itajai University, Santa Catarina, Brazil.
**** Descriptive and Topographic Anatomy Division, Federal University of Sao Paulo, Brazil.
Prof. Dra. Selma Petrella
Rua Rio Grande, 180 Apto. 62
Sao Paulo--Vila Mariana
Sao Paulo--SP, BRASIL
Table I The presence of the inferior (IPAs) in the celiac trunk(CA)cadavers according to gender and statistical result. Gender Presence Male Female Total CA with IPAs 26 5 31 CA with IPAs 46 12 58 Total 72 17 89 [X.sup.2] calc = 0.272 NS