Russell J. Corlett

Superiority of the deep circumflex iliac vessels as the supply for free groin flaps. Clinical work.

In this paper we present 16 cases of free transfer of compound flaps from the groin, 11 using the deep circumflex iliac vessels as a stem and 5 using the superficial circumflex iliac vessels as a stem. We found the deep vessels superior in many ways to the superficial vessels for this purpose; they are larger, permitting greater ease in anastomoses and providing more reliable blood flow. We believe that larger osteocutaneous or myocutaneous flaps can be transferred on the deep vessels than on the superficial ones-and that the deep circumflex iliac flap may supplant the conventional free going flap in most situations. The method evolved in response to patient need, not for surgical éclat.

The versatile deep inferior epigastric (inferior rectus abdominis) flap

Abstract The deep inferior epigastric vascular system nourishes a vast area of the anterior abdominal wall and offers a versatile variety of tissue combinations to the reconstructive surgeon for local or free flap transfer. Its supply to and beyond the rectus abdominis muscle provides the basis for flap design. Eighteen cases are presented to illustrate various muscle, myocutaneous and myosubcutaneous flaps that have been used to date to repair defects in the extremities and in the head and neck. The ease of dissection, coupled with the large calibre and length of the vascular stem, are key factors which combine to offer a speedy and a reliable technique. The donor site scar has been improved by the use of a suprapubic transverse incision to dissect the pedicle and this exposure provides access to the iliac crest for bone grafts where indicated. Time will evaluate this technique and further designs and modifications will undoubtedly be forthcoming. Meanwhile the initial results have been most promising.

The extended deep inferior epigastric flap: a clinical technique.

A versatile flap based on the deep inferior epigastric artery is presented. Its application for local and free-flap transfer is discussed and presented in two clinical cases. The possible inclusion of bone as an osteocutaneous flap is outlined. The flap can be raised with ease and speed, and the donor site is repaired as a linear scar. Since the latissimus dorsi flap with its pedicle based in the axilla has become the workhorse for the upper torso, this extended flap may become its distal counterpart with its pedicle based on the groin.

An anatomic review of the delay phenomenon: II. Clinical applications.

This paper applies the anatomic concepts and data obtained from our animal experimental studies of the delay phenomenon to a series of clinical cases. Similar clinical results were obtained to those seen in Part I of our study when skin flaps were raised with and without a delay, when a tissue expander was used, and when the delay technique was extended to musculocutaneous flaps. In each instance, the cutaneous perforators were identified with the Doppler probe to facilitate the delay of specific vessels rather than dividing those at random. Intraoperative arteriograms and venograms reveal that the choke arteries dilate and the anatomically unfavorable valved vein segments become regurgitant. The end result is the observation that at least one additional anatomic vascular territory can be added to the length of a flap with safety following a surgical delay.

The anterior tibial vessels and their role in epiphyseal and diaphyseal transfer of the fibula: experimental study and clinical applications

The blood supply to the fibula from the anterior tibial and peroneal arteries was investigated in 66 fresh cadaver limbs by India ink injection and radiographic studies. These studies revealed a reliable blood supply to the proximal epiphysis and the proximal two-thirds of the diaphysis of the fibula from the anterior tibial artery. Although the peroneal artery provided the dominant supply to the shaft of the bone, its contribution to the head of the fibula was scanty. The cutaneous supply of each vessel was defined and correlated with the territories of the other vessels supplying the leg. The vascular anatomy of the leg was examined in 100 clinical angiograms, revealing 21 limbs with anomalies. This reinforces the case for preoperative angiogram studies where transfer of the fibula is contemplated. The technique of harvesting the proximal growth plate and the shaft of the fibula on the anterior tibial vessels alone is described and illustrated with two successful clinical cases, each followed for 4 years. The growth rate of the transferred epiphysis averaged 1 cm per year.

The DIEA branching pattern and its relationship to perforators: The importance of preoperative computed tomographic angiography for DIEA perforator flaps

Background: Abdominal donor-site flaps based on the deep inferior epigastric artery (DIEA) are the most common flaps used in autologous breast reconstruction. With significant variation in the vascular anatomy of the DIEA, preoperative imaging is desirable. Computed tomographic angiography, recently described for this purpose, uniquely demonstrates the branching pattern of the DIEA. The authors sought to correlate the DIEA branching pattern to the location and course of perforators as a preoperative planning tool for perforator flaps. Methods: Forty-five cadaveric hemi–abdominal walls were used for contrast injection of the DIEA with subsequent radiographic imaging. The branching pattern on radiography was thus correlated to the location and intramuscular course of perforators, from the main DIEA trunk to the point of the penetrating rectus sheath. Results: The DIEA branching pattern correlated closely with the course of perforators. A bifurcating (type II) branching pattern demonstrated a reduced transverse distance traversed by each perforator, whereas a trifurcating (type III) branching pattern demonstrated significantly greater transverse distances (p = 0.0002). Type I vessels were intermediate. Vessel branching type, however, displayed no significant correlation with the number of perforators (p = 0.56). Conclusions: The distances traversed by perforators were significantly reduced with a bifurcating branching pattern of the DIEA, particularly those originating from the lateral branch, and were greatest with a trifurcating branching pattern. Increased transverse distances correlate with greater rectus muscle sacrificed during perforator flap surgery. As computed tomographic angiography is the optimal modality for demonstrating this pattern preoperatively, the authors suggest its use for preoperative assessment in transverse rectus abdominis musculocutaneous and DIEA perforator flaps.

Anatomical variations in the harvest of anterolateral thigh flap perforators: A cadaveric and clinical study

Background: The anterolateral thigh (ALT) flap has become increasingly popular due to its versatility and minimal donor site morbidity. Its major limitation has been uncertainty in predicting perforator anatomy, with the occasional absence of suitable perforators and high variability in their size and course. The variability of this anatomy has not been adequately explored previously. Methods: A cadaveric study was undertaken, in which 19 thighs (from 10 fresh cadavers) underwent contrast injection and angiographic imaging. Anatomical variations of the vasculature were recorded. A clinical study of 44 patients undergoing ALT flap reconstruction was also undertaken. Perforator anatomy was described in the first 32 patients, and the subsequent 12 patients underwent computed tomography angiography with a view to predicting individual anatomy and improving operative outcome. Results: Cadaver angiography was able to highlight and classify the variations in arterial anatomy, with four patterns observed and marked variability between cases. In 32 patients undergoing ALT flaps without preoperative CT angiography (CTA), five patients (16%) did not have any suitable perforators from the descending branch of the lateral circumflex femoral artery. By selecting the limb of choice with preoperative CTA, the incidence of flap unsuitability was reduced to 0%. Comparing CTA with Doppler, CTA was more accurate (sensitivity 100%) and provided more information. Conclusion: The perforators supplying the ALT flap show significant variability in location and course, with the potential for unsuitable perforators limiting flap success. Preoperative CTA can demonstrate the vascular anatomy and can aid perforator selection and operative success.

The perforator angiosome: A new concept in the design of deep inferior epigastric artery perforator flaps for breast reconstruction

Background: The previously described “perfusion zones” of the abdominal wall vasculature are based on filling of the deep inferior epigastric artery (DIEA) and all its branches simultaneously. With the advent of the DIEA perforator flap, only a single or several perforators are included in supply to the flap. As such, a new model for abdominal wall perfusion has become necessary. The concept of a “perforator angiosome” is thus explored. Methods: A clinical and cadaveric study of 155 abdominal walls was undertaken. This comprised the use of 10 whole, unembalmed cadaveric abdominal walls for angiographic studies, and 145 abdominal wall computed tomographic angiograms (CTAs) in patients undergoing preoperative imaging of the abdominal wall vasculature. The evaluation of the subcutaneous branching pattern and zone of perfusion of individual DIEA perforators was explored, particularly exploring differences between medial and lateral row perforators. Results: Fundamental differences exist between medial row and lateral row perforators, with medial row perforators larger (1.3 mm vs. 1 mm) and more likely to ramify in the subcutaneous fat toward the contralateral hemiabdomen (98% of cases vs. 2% of cases). A model for the perfusion of the abdominal wall based on a single perforator is presented. Conclusion: The “perforator angiosome” is dependent on perforator location, and can mapped individually with the use of preoperative imaging.

Avoiding denervation of rectus abdominis in DIEP flap harvest II: an intraoperative assessment of the nerves to rectus.

Background: The deep inferior epigastric artery perforator (DIEP) flap aims to reduce donor-site morbidity by minimizing rectus muscle damage; however, damage to motor nerves during perforator dissection may denervate rectus muscle. Although cadaveric research has demonstrated that individual nerves do not arise from single spinal cord segments and are not distributed segmentally, the functional distribution of individual nerves remains unknown. Using intraoperative nerve stimulation, the current study describes the motor distribution of individual nerves supplying the rectus abdominis, providing a guide to nerve dissection during DIEP flap harvest. Methods: Twenty rectus abdominis muscles in 17 patients undergoing reconstructive surgery involving rectus abdominis (DIEP, transverse rectus abdominis musculocutaneous, or vertical rectus abdominis musculocutaneous flaps) underwent intraoperative stimulation of nerves innervating the infraumbilical segment of the rectus. Nerve course and extent of rectus muscle contraction were recorded. Results: In each case, three to seven nerves entered the infraumbilical segment of the rectus abdominis. Small nerves (type 1) innervated small longitudinal strips of rectus muscle, rather than transverse strips as previously described. There was significant overlap between adjacent type 1 nerves. In 18 of 20 cases, a single large nerve (type 2) at the level of the arcuate line supplied the entire width and length of rectus muscle. Conclusions: Nerves innervating the rectus abdominis are at risk during DIEP flap harvest. Small, type 1 nerves have overlapping innervation from adjacent nerves and may be sacrificed without functional detriment. However, large type 2 nerves at the level of the arcuate line innervate the entire width of rectus muscle without adjacent overlap and may contribute to donor-site morbidity if sacrificed.

Lymphatic drainage of the nasal fossae and nasopharynx : preliminary anatomical and radiological study with clinical implications

The lymphatic pathways of the nasal cavity are of enormous clinical importance. To date there has been no accurate radiographic record of these pathways.