Study cohortFig. 1

Flowchart of this study. 16 patients were enrolled in this study

This was a retrospective, single-center clinical investigation. Between January 2024 and June 2024, a total of 19 consecutive patients (10 men and 9 women) were enrolled in this study (Fig. 1). All patients had symptoms of intermittent claudication or chronic limb threatening ischemia, thus a catheter examination was performed for diagnosis. One patient was excluded due to the right radial approach, one patient was excluded due to the inability to measure the distance with the catheter due to chronic total occlusion in the external iliac artery, and one patient was excluded due to the disappearance of CT image data. 16 consecutive patients were enrolled in this study. All patients underwent lower limb angiography via the left radial or distal radial arteries. All patients underwent simple computed tomography (CT) with their hands down before and after lower limb angiography. This study was approved by the Ethics Committee of the Kyoto Tanabe Central Hospital (Approval No.: 2024-001).

Computed tomography

The CT scan area ranged from the chest to below the knee. The distances from the left radial artery to the left and right iliac artery bifurcations, left radial artery to the right common femoral artery at the upper femoral border, and left radial artery to the left common femoral artery at the upper femoral border were measured.

CT images were acquired using an Aquilion ONE (Canon Medical Systems Corporation, Otawara, Tochigi, Japan). The detector collimation was 320 × 0.5 mm; the field of view was 500 mm; the gantry rotation speed was 0.5 s; the helical scanning; and the tube voltage was 80 kVp. An automatic exposure control with an SD of 8 was used for the tube current. Images were reconstructed with a slice thickness of 1.0 mm. All data were transferred and analyzed using Ziostation REVORAS (ZIOSOFT Inc, Tokyo, Japan).

Step.1.

A straight line is drawn from the three points of the proximal axillary artery (surgical neck level of the humerus) via the intersection of the radial and ulnar arteries, starting from the radial styloid process. (3 plots)

Step.2.

The axillary artery to the aortic arch is connected as short a distance as possible while following the vascular run. (15–20 plots)

Step.3.

The aortic arch to the iliac artery bifurcation is the shortest possible intravascular distance. (5–8 plots)

Step.4.

The iliac artery bifurcation to the popliteal artery is connected as short a distance as possible while following the vascular run.

Measure the distance between the lines connected by the above method.

Catheter Step.1.

After careful disinfection and local anesthesia, puncture the left radial artery and insert a sheath. The iliac artery contrast study is performed with a pigtail catheter. Radifocus Guide Wire M Standard Type (Terumo Corporation, Tokyo, Japan) was used to select the optimal artery, and if it is difficult, Radifocus Guide Wire M Stiff Type (Terumo Corporation) was used.

Step.2.

Replace the catheter with a 150 cm long multipurpose catheter and contrast the left and right superficial femoral arteries. This may be unilateral depending on renal function and lesion.

Step.3.

After contrasting the superficial femoral artery, withdraw the 150 cm-long multipurpose catheter up to the upper femoral border and measure the length of the extra multipurpose catheter outside the body from the radial styloid process.

Subtract the above from 150 cm to identify the distance from the left radial artery to the common femoral artery at the upper femoral border.

Step.4.

Withdraw the 150 cm-long multipurpose catheter to the iliac artery bifurcation and measure the length of the extra multipurpose catheter outside the body from the radial styloid process.

Subtract the above from 150 cm to determine the distance from the iliac artery bifurcation to the iliac artery bifurcation.

Statistical analysis

All measurements were performed by a clinical technologist. Simple linear regression with Pearson’s correlation coefficient (r), coefficient of determination (R-squared), and p-values were calculated. Statistical significance was set at p < 0.05.