Inferior mesenteric artery: detailed anatomy and morphometry.

Area of Science:

• Vascular Anatomy
• Interventional Radiology
• Surgical Anatomy

Background:

• The inferior mesenteric artery (IMA) is vital for irrigating the distal colon and rectum.
• Precise morphometric data of the IMA is limited, hindering surgical and interventional procedures.
• Understanding IMA anatomy is critical for colon cancer surgeries and percutaneous interventions.

Purpose of the Study:

• To conduct a detailed morphometric analysis of the inferior mesenteric artery.
• To provide essential parameters for optimizing percutaneous vascular treatments.
• To enhance understanding for colon surgeries.

Main Methods:

• Contrast-enhanced computed tomography angiography (CTA) scans from 105 forensic cases were analyzed.
• Multiplanar reconstructions and maximum intensity projections were utilized.
• Measurements of the IMA and its branches, including left colic artery (LCA) trunk length and superior rectal artery (SRA) variations, were performed.

Main Results:

• The left colic artery (LCA) exhibited a short trunk in 38.1% of cases (avg. length 2.4 mm) and a long trunk in 61.9% (avg. length 42.6 mm).
• Superior rectal artery (SRA) variations were classified into three types, with Type 1 (53.3%), Type 2 (38.1%), and Type 3 (8.6%).
• A statistically significant higher number of sigmoid arteries was observed in women (p = 0.001).

Conclusions:

• A short LCA trunk may facilitate procedures due to wider branching angles and larger diameters, improving catheter access.
• The presence of extra superior rectal arteries (SRAs) originating before the sigmoid arteries could influence surgical approaches.
• These findings offer critical anatomical insights for interventional radiologists and surgeons.