Aneurysm, Tortuosity and Kinking of Abdominal Aorta and Iliac Arteries in Thai Cadavers/ Aneurisma, Tortousidad y Torsion de la Parte Abdominal de la Aorta y de las Arterias Iliacas en Cadaveres Tailandeses.
In general, the dilation of the infrarenal abdominal aorta that exceeds 1.5 times or greater than 3 cm in diameter as compared to the normal aortic segment is called abdominal aortic aneurysm (AAA) (Prisant & Mondy, 2004). Of iliac arterial aneurism, it has been reported that the diameter of the common iliac artery exceeds 2 cm, while of external or internal iliac artery approximately exceeded 0.8 cm (Walker et al, 2010; Uberoi et al., 2011). In addition, the assessments of the tortuosity and kinking of arteries have also been described by magnetic resonance angiography (Del Corso et al, 1998; Schep et al, 2001; Kristmundson et al., 2012). The knowledge of prevalence, appropriate detection and surgical management of aortic aneurysm including the tortuosity and kinking of iliac arteries may be useful to decrease the rate of death from the ruptured aorta (Lederle et al, 1995). Some recognitions of these phenomenons are important for treating consideration in the optimizing radiation doses, endovascular stent grafting or traditional surgery (Marin et al, 1995; Quinn et al., 1991; Zarins et al, 1999; Derom & Nout, 2005; Majewska et al., 2011). The objective of present study was to investigate the prevalence of the aortoiliac aneurysm including tortuosity and kinking of iliac arteries in Thai embalmed cadavers. In addition, we attempted to classify the kinking types of the external iliac artery observed.
MATERIAL AND METHOD
This study was carried out in 85 Thai embalmed cadavers (58 males and 21 females) with no vascular disease history, approximately aged between 29 to 95 years (averaged 61.19 [+ or -] 15.11 years), during the period from June 2011 to May 2013, at the Department of Anatomy, Faculty of Medicine, Khon Kaen University.
Assessment of aortic aneurysm. After opening the abdominopelvic wall, the internal organs underneath diaphragm were carefully removed from the posterior abdominal wall to observe and measure the diameter of abdominal aorta and iliac arteries using a vernier caliper. The measuments were performed three times on three different days. As described in a previous study, the abdominal aorta that exceeded 3 cm in diameter was considered as AAA (Prisant & Mondy). In addition, the aneurism of common iliac artery was considered when its diameter exceeded 2 cm, while of external or internal iliac artery was considered if its diameter exceeded 0.8 cm (Walker et al.; Uberoi et al.).
Assessment of the tortuosity and kinking of iliac arteries. Based on the idea of Schep et al., that detected the tortuosity and kinking of iliac artery by magnetic resonance angiography, this study was performed in cadavers by applying a standard goniometer to measure the individual angle of iliac artery. To consider the tortuosity, the angle of the artery was greater than 130 degrees whereas kinking angle was lesser than 130 degrees. Additionally, kinking variations of external iliac artery were classified.
In this study, AAA was found in 4 (4.71%) cases (two males and two females) of in 85 specimens. The diameters of AAA were 5.74, 4.02, 3.67, and 3.27 cm respectively (Fig. 1A-D). Additionally, the aneurysms of iliac arteries were observed (Table I). From 170 sides of common iliac arteries observed, the aneurysm was found in 7 (4.12%) sides. Only internal but not external iliac artery was considered as aneurysm. It was found only on 1 side (0.59%) of 170 sides (Table I). Its diameter was approximately 1.4 cm.
Moreover, the tortuosity and kinking of iliac arteries were observed (Table I). In170 sides of common or external iliac artery, the tortousities were observed in 3 (1.76%, of common iliac artery) sides and in 34 (20%, of external iliac artery). However, no tortuosity of internal iliac artery was found (Table I). In kinking assessments, these were found in common iliac artery (8 sides [4.71%]), external iliac artery (28 sides [16.47%]), and internal iliac artery (2 sides [1.18%]), respectively (Table I).
Furthermore, the patterns of external iliac aortic kinking observed in this study (Fig. 2) were also recorded and could be classified into 4 major types (S-shape; reversed -C shape; low grade shape; and V-shape). Of 170 sides, there were found in the S-shape (14 sides [8.24%]), the reversed -C shape (2 sides [1.18%]), the low grade shape (9 sides [5.29%]) and the V-shape (3 sides [1.76 %]), respectively (Fig. 2).
Clinically, the detailed anatomic assessments of the aneurysm, tortuosity, and kinking of abdominal aorta and iliac arteries are required in consideration for endovascular aortic repair, such as endografting, at abdominopelvic region. For AAA, these anatomic features may include aortic neck length, diameter, and bifurcations (Sprouse et al., 2004). In particular, the data on three dimensions of aortoiliac tortuosity are very important for planning of endovascular repairs (Wolf et al., 2011; Kristmundson et al.). Together with computed tomography assessments, accumulated-anatomic data of abdomino-iliac artery features observed in cadaveric samples could be a primary source to determine as appropriate approach in endovascular repairs.
In this study, we found all abnormal types of abdomino-iliac arteries observed in Thai cadavers (Figs. 1 and 2, Table I). However, the aneurysm, tortuosity, and kinking of abdomino-iliac arteries (except external arteries) were less than 10 percent (Table I). It is possible that all cadavers investigated in this study had no history of vascular diseases (data not shown). Interestingly, only tortuosity (20%), and kinking (16.4%) of the external iliac artery was found to have high evidence as compared to those of other arteries (Table I). Assumed from this study, aging Thais may have a tendency of tortuosity and kinking of the external iliac artery. Moreover, we first demonstrated and classified the patterns of external iliac aortic kinking observed in Thai cadavers into 4 major types: S-shape, reversed, C shape, low grade shape, and V-shape, respectively (Fig. 2). Unfortunately, the computed tomography assessments of the aneurysm, tortuosity, and kinking of abdominal aorta and iliac arteries in Thai patients are limited to co-analyze with our results to elucidate particular prevalence.
In conclusion, this study showed prevalence of the aneurysm, tortuosity, and kinking of abdominal aorta and iliac arteries and demonstrated 4 major kinking variations of external iliac arteries observed in Thai cadavers.
ACKNOWLEDGEMENTS. This study was supported by Department of Anatomy, faulty of Medicine, Khon Kara University. We also would like to thank the research cadaveric committee of the Department of Anatomy for their permission in this research.
Del Corso, L.; Moruzzo, D.; Conte, B.; Agelli, M.; Romanelli, A. M.; Pastine, F.; Protti, M.; Pentimone, F. & Baggiani, G. Tortuosity, kinking, and coiling of the carotid artery: expression of atherosclerosis or aging? Angiology, 49(5)-361-11, 1998.
Derom, A. & Nout, E. Treatment of femoral pseudoaneurysms with endograft in high-risk patients. Eur. J. Vasc. Endovasc. Surg., 30(6):644-1, 2005.
Kristmundsson, T.; Sonesson, B. & Resch, T. A novel method to estimate iliac tortuosity in evaluating EVAR access. J. Endovasc. Ther., 19(2):151-64, 2012.
Lederle, F. A.; Wilson, S. E.; Johnson, G. R.; Reinke, D. B.; Littooy, F. N.; Acher, C. W.; Messina, L. M.; Ballard, D. J. & Ansel, H. J. Variability in measurement of abdominal aortic aneurysms. Abdominal Aortic Aneurysm Detection and Management Veterans Administration Cooperative Study Group. J. Vasc. Surg., 21(6):945-52, 1995.
Majewska, N.; Juszkat, R.; B?aszak, M.; Frankiewicz, M.; Makalowski, M.; Stanisic', M.; Wachal, K. & Majewski, W. Abdominal aorta aneurysm: Case report of high radiation dose during stent-graft implantation. Pol. J. Radiol., 76(4):60-2, 2011.
Marin, M. L.; Veith, F. J.; Lyon, R. T.; Cynamon, J. & Sanchez, L. A. Transfemoral endovascular repair of iliac artery aneurysms. Am. J. Surg., 170(2):119-82, 1995.
Prisant, L. M. & Mondy, J. S. 3rd. Abdominal aortic aneurysm. J. Clin. Hypertens. (Greenwich), 6(2):85-9, 2004.
Quinn, S. F.; Sheley, R. C.; Semonsen, K. G.; Sanchez, R. B. & Hallin, R. W. Endovascular stents covered with pre-expanded polytetrafluoroethylene for treatment of iliac artery aneurysms and fistulas. J. Vasc. Interv. Radiol., 8(6):1051-63, 1991.
Schep, G.; Kaandorp, D. W.; Bender, M. H.; Weerdenburg, H.; van Engeland, S. & Wijn, P F. Magnetic resonance angiography used to detect kinking in the iliac arteries in endurance athletes with claudication. Physiol. Meas., 22(3):415-81, 2001.
Sprouse, L. R. 2nd; Meier, G. H. 3rd; Parent, F. N.; DeMasi, R. J.; Stokes, G. K.; LeSar, C. J.; Marcinczyk, M. J. & Mendoza, B. Is three-dimensional computed tomography reconstruction justified before endovascular aortic aneurysm repair? J. Vasc. Surg., 40(3):443-1, 2004.
Uberoi, R.; Tsetis, D.; Shrivastava, V.; Morgan, R.; Belli, A. M. & Subcommittee on Reporting Standards for Arterial Aneurysms of The Society for Vascular Surgery. Standard of practice for the interventional management of isolated iliac artery aneurysms. Cardiovasc. Intervent. Radiol., 34(1):3-13, 2011.
Walker, T. G.; Kalva, S. P.; Yeddula, K.; Wicky, S.; Kundu, S.; Drescher, P; d'Othee, B. J.; Rose, S. C.; Cardella, J. F.; Society of Interventional Radiology Standards of Practice Committee; Interventional Radiological Society of Europe & Canadian
Interventional Radiology Association. Clinical practice guidelines for endovascular abdominal aortic aneurysm repair: written by the Standards of Practice Committee for the Society of Interventional Radiology and endorsed by the Cardiovascular and Interventional Radiological Society of Europe and the Canadian Interventional Radiology Association. J. Vasc. Interv. Radiol., 21(11):1632-55, 2010.
Wolf, Y. G.; Tillich, M.; Lee, W. A.; Rubin, G. D.; Fogarty, T. J. & Zarins, C. K. Impact of aortoiliac tortuosity on endovascular repair of abdominal aortic aneurysms: evaluation of 3D computer-based assessment. J. Vasc. Surg., 34(4):594-9, 2001.
Zarins, C. K.; White, R. A.; Schwarten, D.; Kinney, E.; Diethrich, E. B.; Hodgson, K. J. & Fogarty, T. J. AneuRx stent graft versus open surgical repair of abdominal aortic aneurysms: multicenter prospective clinical trial. J. Vasc. Surg., 29(2):292-305, 1999.
Department of Anatomy--Faculty of Medicine
Khon Kaen University--123 Mitraparp Road
Khon Kaen, 40002
Porntip Boonruangsri *; Bussakorn Suwannapong *; Somsiri Rattanasuwan * & Sitthichai Iamsaard *
* Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
Caption: Fig. 1. Photographs showing the abdominal aortic aneurysm found in 4 of 85 Thai cadaveric specimens. The most width of aneurysm was measured; A) 5.74 cm, B) 4.02 cm, C) 3.67 cm, and D) 3.27 cm. AAA, abdominal aortic aneurysm; CIA, common iliac artery; EIA, external iliac artery; IIA, internal iliac artery.
Caption: Fig. 2. Photographs (A-D) and schematics (A'-D') showing the 4 types of the external iliac aortic kinking observed in 85 Thai cadaveric specimens. A, A') S-shape; B, B') reversed -C shape; C, C') low grade shape; D, D'), V-shape. CIA, common iliac artery; EIA, external iliac artery; IIA, internal iliac artery.
Table I. Showing prevalence of aortic aneurysm and tortuosity and kinking of iliac artery in 85 Thai cadavers. Sided number (%) Arteries Aneurysm Tortuosity Kinking Abdominal aorta 4 (4.71%) -- -- Common iliac artery 7 (4.12%) 3 (1.76%) 8 (4.71%) External iliac artery -- 34 (20%) 28 (16.47%) Internal iliac artery 1 (0.59%) -- 2 (1.18%)