Case 11: Paramedian forehead flap for nasal soft tissue reconstruction
Authors: Linn Anna Fiehn (MD), Anna Louise Norling (MD) and Magnus Balslev Avnstorp (MD)
67-year-old male was referred to the dept. of Plastic Surgery by his local dermatologist with basal cell carcinoma (BCC) of the infiltrating type localized on the apex nasi, measuring 25 x 25 mm. The diagnosis was previously confirmed by histological analysis of a punch biopsy. Pre-existing conditions: bronchial asthma, adipositas, COPD and AFib. Currently medicated with edoxaban, digoxin and verapamil.
Before and after
Patient examination
The patient appears alert, oriented, and in good general condition. The tumor sits medially on the apex nasi, measures 25 x 25 mm and fills out the entire nasal tip subunit [1]. It presents itself as a pale color with irregular borders, and a non-ulcerous central dent. Overall, the clinical examination agrees with the finding of a BCC. No palpable lymphadenopathy at the head, neck, supra-, or infraclavicular.
Pre-Operative Considerations
Although generally considered to be at very low risk of distant metastasis, the BCCs have a potential of local invasive growth. Tumors’ excision with a 5 mm safety margin is indicated [2]. Taking the psychosociological effect and functional risk of the tumors’ location into account, the best possible reconstruction should follow the necessary excision [3]. The paramedian forehead flap poses an excellent option for the repair of > 20 mm nasal defects and should be considered the gold standard for the reconstruction of this type of defect [4]. The procedure can be safely performed in patients of all ages, with multiple comorbidities, in active smokers, and with no need to adapt the patient’s anticoagulation status [4]. Only treatment with Clopidogrel was described to increase the risk of strong bleeding and should therefore be carefully assessed preoperatively [4].
- Plan: For a paramedian forehead flap, guiding principles suggest the use of a reasonably narrow pedicle (13 – 15 mm), leading to an axial flap pattern defined by blood supply through the supratrochlear artery [4, 5]. Early subperiosteal dissection will ensure adequate blood supply to the flap [4]. Adequate distal thinning and medial rotation of the pedicle will help with correct flap insertion and is followed by donor site closure [4]. After 3-4 weeks, the flap is divided, and the final flap inset is performed.
- Patient information: The procedure can be performed under local anesthesia in the outpatient clinic. As it is a two-step procedure, it includes a 3- to 4-week period between flap elevation + primary inset and flap division + final inset. Depending on tissue quality and availability on the forehead, direct suture is not always possible and the donor site has to potentially heal in secondary intention or receive an allograft, xenograft, equine products, or skin graft [4]. Complications include bleeding, infection, and distal flap necrosis [6, 7]. In line with the experience in our clinic and findings from literature [4-6, 8], we conclude a low perioperative risk and expect an excellent functional and aesthetic outcome.
Step 1: BCC excision
After identifying the excision area, the tumor is removed with a 5 mm safety margin at an appropriate depth into the subcutaneous tissue, leaving a 30 x 30 mm nasal defect. Frozen sections are harvested from the defect borders at 12, 3, 6, 9 o’clock and the base and sent for rapid histological analysis.
- Frozen sections showed no malignancy at the margins at 3, 6, 9, 12 or the base. Therefore, the operation is continued by
Step 2: Flap definition
The pedicle, defined by arterial inflow through the supratrochlear artery is located appr. 20 mm lateral to the midline. A reasonably narrow pedicle (ca. 15 mm) is drawn while blood supply to the flap is monitored by Doppler. A reverse Gilles test at the level of the eyebrow helps to ensure sufficient pedicle length.
Step 3: Flap elevation and thinning
Local anesthetics (Lidocaine + Adrenalin) are administered generously, which also helps to minimize bleeding. The flap is elevated from distal to proximal. Starting to dissect on the level of the galea, subperiosteal dissection begins from ca. 10 mm above the brow to safely capture subperiosteal perforators. The distal part of the flap (15-20 mm) is then thinned to the subcutaneous plane by removal of subcutaneous fat and frontalis muscle until the required thickness for defect reconstruction is achieved.
Step 4: Initial flap inset
Medial rotation is used to bring the tip of the flap down to the defect. The distal one-eighth of the flap is now thinned to the level of the dermis as this part will not be elevated again. Subdermal inverted single sutures with 4-0 absorbable polyfilament followed by cutaneous single sutures with 5-0 non-absorbable monofilament are used to perform flap inset.
Step 5: Donor site closure
In this case, direct closure was possible by a few subdermal inverted sutures using 3-0 absorbable polyfilament to approximate the wound borders followed by a cutaneous layer of cutaneous single sutures using 3-0 non-absorbable monofilament.
Step 6: Wound dressing
Micropore was used on the sutured nasal tip and forehead. However, the posterior, raw side of the pedicle can be significantly inconvenient to the patient if not addressed properly. Therefore, extra care is taken to achieve the best possible hemostasis while not putting the flaps’ blood perfusion at risk. Small bleeding spots were coagulated with the bipolar tweezers and the pedicle was circumferentially dressed with Jelonet.
Step 7: Pre-flap division 34 days postoperative
Final flap division and inset is performed 34 days after initial flap elevation. All suture sites are closed and show no sign of irritation or infection. The flap itself shows adequate perfusion.
Step 8: Flap division and final inset
For flap division and final flap inset, the pedicle is first separated at its origin medially to the eyebrow. To avoid eyebrow asymmetry by traction, a V-shaped skin flap is preserved from the pedicle and fitted to the remaining donor site defect. Next, the pedicle is separated from the flap at the tip of the nose, leaving enough tissue for final defect reconstruction. The flap is then re-elevated for about 50% (elevation is often possible up to 70-80%) [4], proximally thinned to the subcutaneous layer, and adjusted to the defect. Thorough hemostasis is performed. Both the remaining donor site defect as well as the final flap inset are sutured with subdermal inverted sutures using 5-0 absorbable polyfilament followed by cutaneous single sutures using 5-0 non-absorbable monofilament. Sutures are dressed with Micropore and dry gauze.
Post-Operative Plan
If the procedures were performed at the outpatient clinic and according to general guiding principles, the postoperative care for both operations is usually minimal. Dicillin 1000 mg x 4 is administered in a prophylactic dosage. The patient is advised to keep the head elevated and avoid hot food and drinks during the next 24-48 h. Fresh bandages (Micropore for the sutures, Jelonet for the pedicle) are provided for self-conducted dressing changes every other day. Analgesia can be steered by the patient with up to 4 x 1g paracetamol per day. 10 days after initial flap inset, the sutures can be removed at the outpatient clinic together with flap evaluation and division planning. Until then, the patient should avoid exhausting physical activities such as exercise or home chores.
- The paramedian forehead flap should be considered the gold standard for reconstruction of larger nasal tip defects, providing patients predominantly with excellent functional and cosmetic outcomes [4, 5].
- The procedure can be safely performed in an outpatient setting on patients of all ages, with multiple comorbidities and even active smokers [4].
- Multiple adjustments/ extensions can be made to the procedure to best address the individual defect regarding lining, support, and coverage [4].
- Carefully assess for preinstalled Clopidogrel treatment as it puts patients at risk of excessive bleeding [4].
- The degree of thinning is case- and patient-dependent and should therefore undergo constant intraoperative evaluation. Flap thinning in smokers is not recommended and should be done, if necessary, only with great caution in risk of necrosis [4].
- Whenever possible, hair transferal with the flap should be avoided as it can cause hair growth or ingrown hair, which are highly inconvenient to the patient and can be challenging to manage [4].
- If direct donor site closure is not possible, it has to either heal in secondary intention or receive an allograft, xenograft, equine products, or skin graft [4], which can compromise the aesthetic outcome.
- Avoid closing the donor site at the flap rotation point to prevent pinching and venous congestion [4].
References
- Burget, G.C., Aesthetic restoration of the nose. Clinics in plastic surgery, 1985. 12(3): p. 463-480.
- Krammer, C.W., et al., Treatment algorithm for non-melanoma skin cancer. Ugeskr Læger, 2018. 180:V01180044.
- John, J., et al., Outcomes Associated with Nasal Reconstruction Post-Rhinectomy: A Narrative Review. Arch Plast Surg, 2022. 49(2): p. 184-194.
- Correa, B.J., et al., The forehead flap: the gold standard of nasal soft tissue reconstruction. Semin Plast Surg, 2013. 27(2): p. 96-103.
- Menick, F.J., Aesthetic refinements in use of forehead for nasal reconstruction: the paramedian forehead flap. Clin Plast Surg, 1990. 17(4): p. 607-22.
- Chen, C.L., et al., Postoperative Complications of Paramedian Forehead Flap Reconstruction. JAMA Facial Plast Surg, 2019. 21(4): p. 298-304.
- Hammer, D., F. Williams, and R. Kim, Paramedian forehead flap. Atlas of the Oral and Maxillofacial Surgery Clinics of North America, 2020. 28(1): p. 23-28.
- Cerci, F.B., Usefulness of the subunit principle in nasal reconstruction. An Bras Dermatol, 2017. 92(5 Suppl 1): p. 159-162.