High-resolution magnetic resonance angiography of digital arteries in SSc patients on 3 Tesla: preliminary study

Abstract

Objective. We sought to evaluate the use of high-resolution three-dimensional time of flight (3D TOF) magnetic resonance angiography (MRA) at 3 Tesla in the visualization of digital arteries in SSc patients. Methods. A total of 33 patients with SSc [32 females and 1 male; mean (s.d.) age 37.0 (10.2) years; median number of years since onset of RP 3.4 (2.8) years] and 7 healthy controls [6 females and 1 male; mean (s.d.) age 30.7 (3.5) years] were examined on a 3T MR system. A modified high spatial resolution (voxel size = 0.35 × 0.35 × 0.5 mm³) 3D TOF MRA (repetition time/echo time = 19/4.4 ms, flip angle = 15°, slice thickness = 1 mm) was performed during a total scan time of 8 min 22 s. The source images and maximum intensity projection reconstruction were studied; the digital arteries count and lumen area of the selective section of the vessel were measured independently by two experienced radiologists and compared with that of the control ones; and a four-level grading system was made according to the severity. Statistical analysis was performed with t-test and P < 0.05 was used as the criterion. Results. We detected the eight digital arteries in the four fingers (without the thumb) of each case and got a 47.58% presentation in general in the SSc group, and artery No. 5 had the highest presentation rate (70.97%). Statistics showed that the digital arteries No. 1 (P = 0.058) and No. 3 (P = 0.093) had no difference in the lumen area (P > 0.05). We finally got 3 cases in Grade 1, 14 cases in Grade 2, 9 cases in Grade 3 and 5 cases in Grade 4. Conclusion. MRA of the digital arteries in the described technique is a promising method for us to judge the severity of microvascular involvement in finger vessels of SSc patients.