G. Ian Taylor

The Free Vascularized Bone Graft: A Clinical Extension of Microvascular Techniques

For the common problem of lower limb injury with extensive. Loss of skin and bone, a new method of free vascularized bone grafting has been used and integrated with an appropriate soft tissue flap repair. The technique was developed to salvage two legs which would otherwise have been amputated. The preliminary result in Case 2 is encouraging. This case would appear to be the first successful distant transfer of a composite fibular graft by microvascular anastomoses to be reported in man.

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.

Preoperative imaging for DIEA perforator flaps: a comparative study of computed tomographic angiography and Doppler ultrasound.

BACKGROUND Abdominal donor-site flaps, including the transverse rectus abdominis musculocutaneous (TRAM) and deep inferior epigastric artery (DIEA) perforator flaps, are standard in autologous breast reconstruction. With significant variation in the vascular anatomy of the abdominal wall, preoperative imaging is essential for preoperative planning and reducing intraoperative error. Doppler and color duplex sonography have been used with varying results, and the quest continues for optimal preoperative assessment. Computed tomographic angiography has recently been proposed as a noninvasive modality for this purpose. This is the first study to formally compare preoperative Doppler ultrasound with computed tomographic angiography for imaging the DIEA. METHODS Eight consecutive patients undergoing DIEA perforator flap surgery for breast reconstruction underwent both computed tomographic angiography and Doppler ultrasound preoperatively. All investigations and procedures were performed at the same institution with the same primary and assisting surgeons and the same radiology team. RESULTS Computed tomographic angiography was superior to Doppler ultrasound at identifying the course of the DIEA and its branching pattern, and in visualizing its perforators. Preoperative computed tomographic angiography was highly specific (100 percent) and more sensitive in mapping and visualizing perforators (p = 0.0078). It was also proficient at identifying the superficial epigastric arterial system and for effectively displaying the results intraoperatively. It was substantially quicker and removed the interobserver error associated with Doppler ultrasonography. The study was ceased after eight patients because of the overwhelming benefit of computed tomographic angiography over Doppler ultrasonography. CONCLUSION Computed tomographic angiography is a valuable imaging modality for the preoperative assessment of the donor-site vascular supply for TRAM and DIEA perforator flaps.Background: Abdominal donor-site flaps, including the transverse rectus abdominis musculocutaneous (TRAM) and deep inferior epigastric artery (DIEA) perforator flaps, are standard in autologous breast reconstruction. With significant variation in the vascular anatomy of the abdominal wall, preoperative imaging is essential for preoperative planning and reducing intraoperative error. Doppler and color duplex sonography have been used with varying results, and the quest continues for optimal preoperative assessment. Computed tomographic angiography has recently been proposed as a noninvasive modality for this purpose. This is the first study to formally compare preoperative Doppler ultrasound with computed tomographic angiography for imaging the DIEA. Methods: Eight consecutive patients undergoing DIEA perforator flap surgery for breast reconstruction underwent both computed tomographic angiography and Doppler ultrasound preoperatively. All investigations and procedures were performed at the same institution with the same primary and assisting surgeons and the same radiology team. Results: Computed tomographic angiography was superior to Doppler ultrasound at identifying the course of the DIEA and its branching pattern, and in visualizing its perforators. Preoperative computed tomographic angiography was highly specific (100 percent) and more sensitive in mapping and visualizing perforators (p = 0.0078). It was also proficient at identifying the superficial epigastric arterial system and for effectively displaying the results intraoperatively. It was substantially quicker and removed the interobserver error associated with Doppler ultrasonography. The study was ceased after eight patients because of the overwhelming benefit of computed tomographic angiography over Doppler ultrasonography. Conclusion: Computed tomographic angiography is a valuable imaging modality for the preoperative assessment of the donor-site vascular supply for TRAM and DIEA perforator flaps.

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 vascular territories of the anterior chest wall

A series of 31 fresh cadaver injection, dissection and radiographic studies were undertaken to define the vascular architecture of the anterior chest wall and to correlate the findings of previous writers in this area. The findings confirmed that the dominant supply to this region is from the internal thoracic artery which interconnects in all layers with the posterior intercostals, the lateral thoracic, the acromio-thoracic and the transverse cervical arteries. The dominant cutaneous perforators of these vessels are concentrated around the perimeter of the pectoralis major muscle, the costal margin and over the interdigitations of the serratus anterior muscle in the mid-axillary line. The clinical significance of these findings is discussed with particular reference to the design of various breast reduction procedures and the planning of flaps in this area. Of special note is the observation that the concentration of large perforators which exists along the inframammary crease arises from the anterior intercostal vessels in the fifth and sixth intercostal spaces.

The angiosomes of the body and their supply to perforator flaps.

An angiosome is a composite block of tissue that is supplied anatomically by source (segmental or distributing) vessels that span between the skin and bone. In addition to supplying the deep tissues, the source vessels of these angiosomes supply branches to the overlying skin, which pass either between the deep tissues or through the deep tissues, usually muscle, to pierce the outer layer of the deep fascia, usually at fixed skin sites. Hence, perforator flaps, when dissected to the underlying source vessels, involve tracing vessels either between the deep tissues, whether muscle tendon or bone, or through the deep tissues, usually muscle.

The anatomy of the subscapular-thoracodorsal arterial system: study of 100 cadaver dissections

The results of 100 cadaver dissections of the subscapular-thoracodorsal arterial system are presented. These results confirm the anatomical reliability of the thoracodorsal artery and report the consistent presence of a branch of the thoracodorsal artery to the serratus anterior muscle. The branches to serratus anterior were of sufficient dimensions to support either a latissimus dorsi flap or a serratus anterior flap. A direct cutaneous branch from the thoracodorsal artery to the skin of the axilla was identified in only 47% of the dissections.

The lymphatic anatomy of the breast and its implications for sentinel lymph node biopsy: A human cadaver study

BackgroundCurrent understanding of the lymphatic system of the breast is derived mainly from the work of the anatomist Sappey in the 1850s, with many observations made during the development and introduction of breast lymphatic mapping and sentinel node biopsy contributing to our knowledge.MethodsTwenty four breasts in 14 fresh human cadavers (5 male, 9 female) were studied. Lymph vessels were identified with hydrogen peroxide and injected with a lead oxide mixture and radiographed. The specimens were cross sectioned and radiographed to provide three dimensional images. Lymph (collecting) vessels were traced from the periphery to the first-tier lymph node.ResultsLymph collecting vessels were found evenly spaced at the periphery of the anterior upper torso draining radially into the axillary lymph nodes. As they reached the breast some passed over and some through the breast parenchyma, as revealed in the cross-section studies. The pathways showed no significant difference between male and female specimens. We found also perforating lymph vessels that coursed beside the branches of the internal mammary vessels, draining into the ipsilateral internal mammary lymphatics. In some studies one sentinel node in the axilla drained almost the entire breast. In most more than one sentinel node was represented.ConclusionThese anatomical findings are discordant with our current knowledge based on previous studies and demand closer examination by clinicians. These anatomical studies may help explain the percentage of false-negative sentinel node biopsy studies and suggest the peritumoral injection site for accurate sentinel lymph node detection.

The Angiosomes of the Head and Neck: Anatomic Study and Clinical Applications

The angiosome concept was introduced over a decade ago by Taylor and Palmer, whereby the body was considered to be composed anatomically of multiple three-dimensional composite blocks of tissue supplied by particular source arteries. Since then, detailed studies of the forearm and leg have been examined by Taylor and his coworkers. This study focuses on another region—the head and neck. Six fresh head and neck cadaver specimens were examined after infusion with a radio-opaque lead oxide mixture and correlated with over 24 previous body studies. The vascular anatomy of the skin, superficial musculoaponeurotic system (SMAS), muscles, brain, dura, and bone was examined. Each layer was painstakingly removed, photographed, labeled, and mapped to the respective arteries and veins. A radiologic subtraction technique was used to allow successive layers to be compared. This information was then scanned into a computer, analyzed, color coded, and labeled, thereby producing a three-dimensional study of the head and neck region to identify the respective angiosomes. As in previous detailed examinations of the leg and forearm, the angiosomes were found to be connected usually within tissues, such as muscle, skin, specialized organs or glands, rather than between the tissues. The muscles usually had vessels of two or more angiosomes supplying them and fell into three major groups based on the similarity of their arterial supply. In some areas, the midline anastomoses were rich, especially in the integument of the scalp, forehead, and lips. In other regions, the midline vascular connections were poor, especially in the tongue and palate. No fewer than 13 angiosomes of the head and neck, supplied by the branches of the external carotid, internal carotid, and subclavian arteries, have been defined, mapping their three-dimensional territories in the skin, the deep soft tissues, and the bones. Although most angiosomes spanned between skin and bone, three territories, those of the vertebral, lingual, and ascending pharyngeal vessels, were confined to the deep tissues without cutaneous representation. Finally, this study provides additional data for the surgeon to help plan safer incisions and better reconstructive flap procedures. It also gives information that may help explain the etiology and treatment of head and neck arteriovenous vascular malformations. (Plast. Reconstr. Surg. 105: 2287, 2000.)