Evolving Concepts of Keystone Perforator Island Flaps (KPIF): Principles of Perforator Anatomy, Design Modifications, and Extended Clinical Applications.

BACKGROUND: Keystone flaps have demonstrated growing clinical applications in reconstructive surgery in the past decade. This article highlights flap modifications and their versatility for clinical applications and management of complex defects. METHODS: A retrospective chart review was conducted of consecutive patients undergoing keystone flap reconstruction at the authors' institution from January of 2012 to December of 2014. Patient demographics, indications, and operative and postoperative details were abstracted. RESULTS: Forty-two keystone flaps were performed in 36 patients. Indications included malignant melanoma (n = 14), soft-tissue sarcoma (n = 12), benign pathologic conditions (e.g., exposed hardware, enterocutaneous fistula, tissue necrosis) (n = 6), and nonmelanoma skin cancer (n = 4). Twenty-eight percent received neoadjuvant irradiation, and 70 percent of these were for sarcoma. Locoregional adjunct flaps were performed in eight patients. The deep fascia was nearly completely in a circumferential manner in 18 of 36 patients (50 percent), in 92 percent of the sarcoma reconstructions, and located mainly in the lower extremity. Average defect size was 215 cm (range, 4 to 1000 cm). Average defect size was 474 cm and 35.8 cm after sarcoma and malignant melanoma resection, respectively. Average flap size was 344 cm (range, 5 to 1350 cm). Ninety percent of cases had flap sizes exceeding the traditional 1:1 ratio. There was no flap loss or partial necrosis. Mean time to mobilization was 1.8 days, and mean hospital length of stay was 6.8 days. CONCLUSIONS: Keystone flaps offer an excellent versatile tool for reconstructive surgeons. Fundamental principles behind the vascular basis of the keystone flap and its modifications permit their greater utility in complex wounds in the settings of large oncologic resections, irradiation, and trauma. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The cervico-submental keystone island flap for locoregional head and neck reconstruction.

BACKGROUND: Locally advanced head and neck cancer often requires wide resections of the cheek and parotid gland, and in an ageing population preferred reconstructive options aim to avoid lengthy operating times or high risk surgery. While most large parotid defects traditionally require free flap reconstruction, we describe a new and versatile locoregional flap that has been shown to be reliable, simple and safe. METHODS: We describe the cervico-submental (CSM) keystone-design perforator island flap for head and neck reconstruction, including an analysis of 33 consecutive patients with a range of head and neck defects. The flap was raised based on perforators of the external carotid artery and its branches, and designed to overlay the C2/C3 dermatomes (an aide memoire for flap design). The indications, and surgical technique are described. RESULTS: In 33 consecutive patients, no major complications were encountered. Five patients developed superficial infections, one developed post-operative bleeding and one patient developed partial tip necrosis. Theatre time was considerably shorter than our alternative reconstructive options. CONCLUSION: The CSM keystone-design perforator island flap is a novel and versatile flap, which can be used in a range of advanced cheek and parotidectomy defects, and may enable improved surgical management in an increasingly elderly and high-risk population.

Quadriceps keystone island flap for radical inguinal lymphadenectomy: a reliable locoregional island flap for large groin defects.

BACKGROUND: Radical inguinal lymphadenectomy (RIL) for bulky metastatic melanoma and non-melanoma skin cancers of the inguinal region, while shown to improve morbidity and survival oncologically, can result in substantial morbidity from wound complications. Skin defects cannot be closed primarily and the substantial dead space predisposes to seroma, wound dehiscence and infection. Despite the clear need for reconstructive options, extended series describing reconstruction of large inguinal defects in this setting have not been reported. METHODS: A prospectively entered, retrospectively reviewed study of 20 consecutive patients undergoing quadriceps keystone island flaps (QKIF) for the closure of complicated inguinal defects is described. RESULTS: There was 100% flap survival, with no partial or complete flap losses. A reduction in wound breakdown/dehiscence from reported rates was seen, with four patients (20%) having wound breakdown, compared to double that rate in reported series. Other wound complications comprised six patients (30%) with mild wound infections, seven patients (35%) with seromas and two patients (10%) with haematomas. CONCLUSION: The QKIF is an effective means of reconstructing inguinal defects after RIL, particularly in high-risk patients, and is technically simpler than other reconstructive techniques advocated for this purpose. Furthermore, the QKIF offers patients with advanced disease (where management is primarily palliative) a potentially improved quality of life with reduced operative morbidity.

Oncologic clearance with preservation of reconstructive options: literature review and the 'delayed reconstruction after pathology evaluation (DRAPE)' technique.

Intraoperative frozen section and Mohs' micrographic surgery (MMS) are two techniques used to ensure oncological clearance without resorting to unnecessarily wide margins that might compromise reconstructive options for definitive wound closure. In addition to some technical issues, these techniques are suboptimal for resection of tumours such as melanoma, where specific tissue margins at histopathology are required to ensure minimal risk of local recurrence. We describe a technique that minimizes the amount of tissue excised and uses definitive paraffin sections interpreted in a pathology laboratory in order to delay reconstruction until after clear oncologic margins are obtained. This 'delayed reconstruction after pathology evaluation (DRAPE)' technique is particularly directed at extensive and complicated skin lesions, located in areas of the body that can be difficult to reconstruct and are prone to disfigurement and/or loss of function. A review of the literature is undertaken, establishing the role of each technique in achieving clear surgical margins. A case example is presented, highlighting the role of the DRAPE approach. The DRAPE technique is presented as a useful option for high-risk lesions, especially within aesthetically sensitive regions or for complex reconstructions, and when reconstruction can be reasonably delayed while tumour clearance is established.

Keystone island flap reconstruction of parotid defects.

BACKGROUND: Skin cancers of the face and scalp have a propensity to metastasize to the parotid group of lymph nodes. The resection of these secondary tumors and other primary tumors in the parotid region often results in defects requiring flap reconstruction. Pectoralis major flaps are reliable and free flaps are arguably the criterion standard. However, we have found keystone island flaps to be a simple and robust alternative, with low donor-site and patient morbidity. The aim of this article is to share our surgical technique, experience, and outcomes of reconstructing parotid defects with keystone island flaps. METHODS: The authors retrospectively reviewed 62 patients who had 63 parotid defect reconstructions at a single institution from 2004 to 2009 (5-year period). RESULTS: The diseases involved were squamous cell carcinoma (52 cases), melanoma (five cases), basal cell carcinoma (four cases), and others (two cases). Nine patients presented with a previous history of radiotherapy and 33 patients required adjuvant radiotherapy. Seven patients (11 percent) suffered postoperative complications necessitating a return to the operating room. CONCLUSIONS: Keystone island perforator-based flaps present an alternative to free tissue transfer. From the series presented, it can be seen that reliable and reproducible results are achievable. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The superior thyroid artery perforator flap: anatomical study and clinical series.

UNLABELLED: The redundant tissues of the anterior neck are well suited as a donor site for fasciocutaneous flaps in head and neck reconstruction, with similar skin quality and numerous underlying perforators. However, historic cadaveric research has limited the use of this as a donor site for the design of long and/or large flaps for fear of vascular compromise. The authors undertook an anatomical study to identify the vascular basis for such flaps and have modified previous designs to offer the versatile and reliable superior thyroid artery perforator (STAP) flap. Forty-five consecutive computed tomographic angiograms of the neck were reviewed, assessing the vascular supply of the anterior skin of the neck. Based on these findings, eight consecutive patients underwent head and neck reconstruction using a flap based on the dominant perforator of the region. In all cases, a perforator larger than 0.5 mm was identified within a 2-cm radius of the midpoint of the sternocleidomastoid muscle at its anterior border. This perforator was seen to emerge through the investing layer of deep cervical fascia as a fasciocutaneous perforator and to perforate the platysma on its ipsilateral side of the neck, proximal to the midline. This was seen to be a superior thyroid artery perforator in 89 of 90 sides and an inferior thyroid artery perforator in one case. Eight consecutive patients underwent preoperative imaging and successful flap planning and execution based on this dominant perforator. The superior thyroid artery perforator (STAP) flap demonstrates reliable vascular anatomy and is well suited to reconstruction of a broad range of head and neck defects. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Use of the keystone island flap for advanced head and neck cancer in the elderly--a principle of amelioration.

Traditional management strategies of advanced head and neck cancer in the elderly include palliation and radical resection with microsurgical reconstruction. The keystone flap approach is an alternate reconstructive technique with a range of benefits for the aging population. This publication presents a series of elderly patients with head and neck cancer who underwent resection and reconstruction using the keystone flap principles. The aim is to demonstrate the value of this reconstructive technique in the various anatomical regions of the head and neck. Various operative sequences are accompanied by illustrations and discussions of the underlying principles.