23 Tenzel Semicircular Flap
Summary
The Tenzel semicircular flap was first described in 1975 by Dr. Richard Tenzel and consists of an advancement-rotational musculocutaneous flap used for direct closure of moderate-sized lower or upper eyelid defects. The procedure involves creating a semicircular skin-muscle flap rotated either upward or downward from the lateral canthal angle with selective cantholysis and advancement of the flap for direct closure. Drs. Levin and Buckman modified the procedure in 1986 to include the release of the lower eyelid retractors and inferior orbital septum to allow for more laxity and the closure of larger defects. The semicircular flap is a particularly useful technique with successful cosmetic and functional outcomes that is performed in a single stage and avoids the need for grafting of other tissues. There are several potential complications, including ectropion, lid retraction, lateral canthal webbing or dystopia, and notching of the lid margin. These may be avoided with appropriate surgical planning and technique.
23.1 Goals
The goals of the semicircular flap are anatomical, functional, and cosmetic reconstruction of lower or upper eyelid defects of moderate size. 1 As with any eyelid reconstruction, it is important to create an anatomically stable and cosmetically acceptable eyelid and margin and to restore the functional ability of the eyelid to protect and lubricate the eye.
23.2 Advantages
There are several advantages to the Tenzel semicircular flap. The semicircular design of the flap generates more lateral movement of the graft than a straight-line design would permit. 1 , 2 , 3 , 4 The procedure is performed in a single stage and does not require temporary closure of the eyelids. This is in contrast to a tarsoconjunctival flap from the upper eyelid. Furthermore, the semicircular flap does not require grafting or manipulation of other nonadjacent tissues. It utilizes the adjacent lateral eyelid margin tissue with natural lashes for direct closure, which promotes a more favorable cosmetic appearance compared to utilizing grafted tissue without lashes. In the semicircular flap, the medially mobilized periorbital tissue that does not contain lashes is limited to the lateral eyelid.
23.3 Expectations
The semicircular flap is a reliable procedure and the surgeon can expect a reasonable cosmetic outcome with good functionality of the reconstructed eyelid. There are several minor complications that have been reported, many of which may be avoided with the appropriate preoperative planning and surgical techniques. 5
23.4 Key Principles
The semicircular flap is an advancement-rotational musculocutaneous flap used for direct closure of moderate-sized lower or upper eyelid defects. 1 , 2 , 3 , 4 It should be considered when the size of the defect would not permit direct closure alone. The technique recruits the adjacent lateral remaining eyelid and periorbital tissue. It was first described in 1975 by Dr. Richard Tenzel. 2 , 3 The original technique was modified by Drs. Levine and Buckman to promote further mobilization by freeing the attachments of the inferior orbital septum and the lower eyelid retractors. 4 The approach to the semicircular flap varies on an individual basis, depending on the size and location of the defect, the degree of tissue laxity, and the personal preferences of the surgeon.
23.5 Indications
The Tenzel semicircular flap can be used for closure of moderate-sized upper or lower eyelid defects, which have been described as defects involving 1/3 to 1/2 of the eyelid margin. The degree of lid laxity should be considered when determining its use. 1 , 2 , 3 , 4 , 5 , 6 Several reports of this technique are being used to successfully repair defects involving up to 80% of the eyelid. 4 , 5 This procedure is best for repair of central eyelid defect with at least 2 mm of remaining tarsus on the lateral and medial wound, but has also been utilized in cases where there is minimal tarsus laterally or medially. 3 The semicircular flap is typically used for reconstruction following surgical excision of tumors or other eyelid lesions, but it may also be used for repair of traumatic defects if there is sufficient remaining tissue.
23.6 Contraindications
The Tenzel semicircular flap should not be utilized for large upper or lower eyelid defects where there is not sufficient tissue mobilization for adequate closure. Large defects are defined as involving over 50% of the upper or lower eyelid margin. While there are many reports of the semicircular flap technique being used for defects involving up to 75 to 80% of the margin, other techniques, including the Hughes flap and the Cutler-Beard procedure, may be recommended for eyelid margin defects greater than 50%. 1 , 4 , 5 , 6 , 7 Lack of tarsal remnant on the lateral or medial wound edge may limit the ability to utilize the Tenzel semicircular flap by decreasing lid stability of the final reconstruction, thereby increasing the risk for postoperative lid malposition. 3