A Study Of Medial Forearm Flap Cutaneous Perforators With Color Doppler Flow Imaging

Objective:To study the distribution, localization and hemodynamic parameters of the blood vessel of medial forearm flap (MFF) with color doppler flow imaging (CDFI). Methods:We examined 80 normal volunteers' cutaneous perforators on both medial forearm with a broad-spectrum 7.5～13MHz linear transducer.The source,mumber, diameter, course,location, and the hemodynamic parameter were recorded.All these data were analyzed statistically. The patient's medial forearm length was measured from the styloid process of ulna to medial epicondyle of humerus.This line corresponds to the lateral intermuscular septum between the vastus lateralis muscle and the rectus femoris muscle(D). CDFI was applied to detect vascular trunks and perforators (caliber≥0.5mm) of the medial flap of bilateral forearms.Results:The vascular figuration, distribution and localization of the artery trunks, such as brachial artery (BA), ulnar artery (UA),common interosseous artery (CIA), inferior ulnar collateral artery (IUCA) and ulnar recurrent artery (URA), were clearly shown, as well as did the caliber, distribution, localization and the position relation with subcutaneous tissue of the artery perforators, which revealed an bilateral asymmetry in number, derivation, distribution, localization and the points penetrating the deep fascia of the perforators.645 artery perforators (caliber≥0.5mm), extended from proximal to distal limbs horizontally and upward, were detected in 160 medial forearm flaps. The average number of the detected perforators in each flap was 4.03 (range,3 to 6). The length of their pedicels ranged from 3.44 to 28.8mm. They were classified into 3 types:Ⅰmyocutaneous perforators (12.4%);Ⅱseptocutaneous perforators (83.7%);Ⅲdirect cutaneous perforators (3.9%). The calibers of BA, IUCA and URA were respectively 2.8±0.4,1.65±0.54 and 1.32±0.52 mm. The calibers of the distal, intermediate and proximal part of UA were respectively 2.22±0.63,2.39±0.58 and 2.64±0.64 mm. The widest perforator had an external diameter of 1.0±0.3 mm. Among the total perforators,87.5% of the 645 perforators was found to originate from the 2th,3th,4th and 8th sections of the ligature between the ulna and the radius.88.1% of the widest perforators was found to originate from the 2th,4th,7th and 8th sections of the ligature between the ulna and the radius.86.3% of the perforators was found penetrating the deep fascia from the 2th,7th and 8th sections of the ligature between the ulna and the radius. The UA caliber in normal people decreased progressively from proximal to distal part of UA. The difference in UA caliber between bilateral forearms was not statistically significant. On the other hand, the difference in UA caliber between males and females was statistically significant (P<0.05). In systole, the peak value of flow velocity decreased progressively. The pattern of waveform demonstrated varied types, such as one-way double-humped wave, two-way triple-humped wave, one-way triple-humped wave and so on. The proportions of the two-way triple-humped waves were decreased progressively from proximal to distal part of the artery. The one-way double-humped wave predominated the waveform patterns of the artery perforators. But in diastole, the flow velocity in the perforators almost faded away and the waveform indicated a monophase pattern with low velocity and high resistance. Others showed a two-way triple-humped wave type. There were not statistically significant differences in the peak value of UA and all perforators between bilateral forearms or between two groups.Conclusions:(1) CDFI technique can clearly show the figuration of UA and detect the parameters of this artery, through which the disorders and variance of UA will be identified. (2) CDFI can vividly display the derivation, distribution, localization of the perforators of MFF. (3) CDFI can be applied to access the vascular status to underlie the surgical design of MFF and to monitor the vascular status at the follow-up.