Angiotomodensitométrie préopératoire dans les lambeaux perforants : standardisation du protocole

Feasibility study of preoperative microvessel evaluation and characterization in perforator flaps using various modes of color-coded duplex sonography (CCDS)

BACKGROUND

Color-coded duplex sonography (CCDS) is useful for perforator flap design showing the highest sensitivity in identifying microvessels. This prospective study evaluates the feasibility of different ultrasound (US) modes applied by the microsurgeon in daily practice suggesting quantifiable reference values.

METHODS

Twenty-four patients aged between 17 and 68 years (mean 43.3 ± 14.2 years) with 18 anterolateral thigh (ALT) and 6 superficial circumflex iliac artery (SCIP) flaps were included. Indications were traumatic (n = 12), infectious (n = 6), ischemic (n = 4), or tumor-associated defects (n = 2). Different US modes were evaluated regarding applicability using multifrequency linear probes (5-15 MHz). Vessels diameter, peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were measured. Preoperative results were correlated to intraoperative findings.

RESULTS

In the examined patient group with 24 perforator flaps a 100% correlation was seen when comparing perforators detected with CCDS/PD with intraoperative findings using optimized US settings. Sensitivity, PPV, and accuracy of CCDS were 100% respectively. Mean PSV of 16.99 ± 6.07 cm/s, mean EDV of 5.01 ± 1.84 cm/s and RI of 0.7 ± 0.07 were measured in microvessels (PW-mode). CCDS proved to be superior compared to PD in correct diameter assessment showing a mean diameter of 1.65 ± 0.45 mm, compared to PD-mode 1.31 ± 0.24 mm. Mean PSV and EDV were higher in ALT than in SCIP flaps, RI was slightly higher in SCIP flaps (p > .05). There were no significant differences in size of different flaps' perforators (p > .05).

CONCLUSION

CCDS represents a highly valuable tool in the daily practice of free flap reconstructions using optimized low flow US settings and multifrequency linear probes.

Step-by-step guide to ultrasound-based design of alt flaps by the microsurgeon - Basic and advanced applications and device settings

BACKGROUND

The anterolateral thigh (ALT) perforator flap is a popular reconstructive tissue transfer. Consistent with the "hot/cold zone" concept for rapid dissection and thin flap harvest, reliable preoperative perforator mapping is mandatory. Color-coded duplex sonography (CCDS) has been shown to have the highest pooled sensitivity and positive predictive value to identify ALT perforating vessels. By reviewing this guide, the reader should learn: 1. Probe selection and basic/advanced device settings 2. Interpreting tissue morphology 3. Structured mapping approach 4. Pedicle position planning 5. Safe flap design 6. Assess subcutaneous course and flap's thickness for subfascial/epifascial/suprafascial harvest 7. Implement perforators identified into a tailor-made flap design including chimeric flaps.

METHODS

Experiences with ultrasound-guided flap design gained from 125 ALT perforator flap free tissue transfers performed in two reconstructive centers was the basis of our guide. Our structured method comprises standardized markings, patient positioning, and simple ergonomics. Basic and advanced CCDS settings, selection, and conventional probe guidance are outlined for the microsurgeon.

RESULTS

Linear multifrequency probes (6-15 MHz) were used. Best preset programs were breast, thyroid, and vascular. Favorable device properties were depth focused to 2-5 cm, pulse repetition frequency (PRF/Scale) set low to 0.5-1.5 kHz/3-10 cm/s, color gain high, and wall filter (WF) low/off (< 50 Hz). Additional parameters were discussed. A 100% concordance rate was seen comparing preoperative perforator visualization with CCDS and intraoperative findings. Detailed picture and video material were demonstrated.

CONCLUSION

CCDS is a powerful tool for preoperative perforator mapping in perforator flaps such as the ALT.

An anatomic study of deep inferior epigastric artery diameters at the origin from external iliac and at the lateral border of rectus abdominis muscle by computed tomographic angiography from autologous breast reconstruction patients

BACKGROUND

Autologous breast reconstruction by means of microsurgical abdominal flaps is an very well described technique. The flap harvest dissection under inguinal ligament would cause the risk of parietal weakening in this zone and postoperative bulging. The goal of our study is to investigate whether the deep inferior epigastric artery diameter remains constant from its exit of the external iliac artery to its entrance in the rectus muscle sheath.

PATIENTS AND METHOD

One hundred arteries were studied on fifty preoperative computed tomographic angiographies made before a DIEAP flap for breast reconstruction. We measured the caliber of the left and right deep inferior epigastric arteries at these two landmarks. The length of this artery between these was also calculated. This data were collected with specific angiography reconstruction.

RESULTS

At the caudal landmark, the mean DIEA diameter was 2.1±0.27mm on the left side and 2.1±0.31mm on the right side. At the cephalic landmark, the mean DIEA diameter was 2.0±0.28mm on the left and 2.0±0.27mm on the right side (P=0.00035 at left side; P=0.0089 at right side). The mean pedicle length between the two landmarks was 22.3±2.85mm on the left side and 22.2±2.98mm on the right side.

CONCLUSION

This computed tomographic angiography study showed that the diameter of DIEA is equivalent at its origin and at the lateral border of muscle. Flap harvest without dissection under inguinal ligament provides sufficient pedicle length and caliber to allow for comfortable and reliable sutures.

[Phalloplasty: Microsurgical options and management algorithm]

The free radial forearm flap is considered as the gold standard in penile reconstruction for good functional and aesthetic results. The scar on donor site could be considered as pathognomonic of their situation by transsexual patients. The development of microsurgical flaps provides new therapeutic options. This options are discussed and a therapeutic algorithm is presented. The main techniques used are the pedicled anterolateral thigh perforator flap and free muscle sparing latissimus dorsi flap. Principal criteria are listed, the choice of patient and the local anatomical conditions are the most important. Antebrachial flap stay the first choice. In case of non-feasibility of this flap, phalloplasty with pedicle ALT flap or free MSLD flap will be proposed. Urethral reconstruction will be done by a narrow free forearm flap or by a delayed thin skin graft or buccal mucosa graft. Microsurgical phalloplasty options are not limited to the forearm flap. Satisfactory results can be obtained using alternative procedure. The use of a therapeutic algorithm allows to choose the most optimal solution for each patient.

[Coverage of anterior knee defect by reverse flow anterolateral thigh flap: About two cases]

The coverage of soft-tissue defects concerning the front of the knee and the proximal lower leg is a complex procedure. The reverse flow anterolateral thigh flap represents a good solution for this defects, especially when the coverage surface is large-sized and a free flap is not appropriate regarding the difficulty of the process. Flap retrograde vascularization is based on the anastomosis between the descending branch of the circumflex femoral artery and lateral superior genicular artery. It is an easy solution with low morbidity. The authors have chosen this flap to cover soft-tissue defect of anterior knee from two patients with total knee prothesis.

[Reconstruction of an abdominal wall defect with a superior epigastric perforator propeller flap: case report]

Perforators flaps take a special place in reconstructive surgery. These flaps can be dissected and turned as a propeller blade on its pedicule axis. We report the case of a 54-year-old man presenting a recurrence of a dermatofibrosarcoma in the right hypochondrium. Tumor resection caused a large abdominal wall defect taking the anterior aponeurosis of the rectus abdominis. An angioscanner was realized in preoperative to locate the perforators of the deep superior epigastric artery. We realized a propeller flap based on a perforator of the left superior epigastric artery who allowed to cover the wall defect. We set up a patch of Vicryl® to reconstruct the aponeurosis plan at the same operative time. We didn't note any necrosis and complete healing occurred in 2 weeks. The margins were healthy. The cosmetic result and the low morbidity make this flap a good therapeutic option. This flap seems reliable, arteries perforators are constant with good diameter.