Nasolabial Fold Retrograde Island Flap With Local Heparin Injection For Nasal Defect Repair Following Basal Cell Carcinoma Excision

Summary

This protocol demonstrates the surgical technique for repairing nasal defects using a nasolabial fold retrograde island flap, combined with immediate postoperative local heparin sodium microinjection to prevent venous congestion and enhance flap survival.

Abstract

Basal cell carcinoma (BCC) frequently involves the external nose, necessitating radical surgical excision that often results in complex soft-tissue defects. While the nasolabial fold retrograde island flap offers an aesthetically superior reconstructive option due to its excellent color and texture match, its reliance on a reverse-flow subcutaneous pedicle makes it highly susceptible to venous congestion, which can compromise flap survival. The goal of this protocol is to demonstrate a modified surgical technique that incorporates immediate postoperative local microinjection of heparin sodium to mitigate this specific vascular risk. The procedure involves the radical excision of the nasal tumor, followed by the harvesting and rotation of a subcutaneous pedicle island flap from the ipsilateral nasolabial fold. To address the challenge of venous stasis, heparin sodium is micro-injected into the full thickness of the flap in a multi-point grid pattern immediately after suturing. This intervention utilizes both pharmacological anticoagulation to prevent microthrombosis and mechanical decompression via needle puncture to facilitate venous drainage. In a clinical application involving 24 patients, this protocol achieved a 100% flap survival rate. Early signs of severe venous congestion observed in three cases (12.5%) were successfully reversed within one week through continuous local heparin therapy. Advanced clinical data analysis indicated that flap size was not an independent predictor of venous congestion, demonstrating the robustness of this technique even for larger defects. Furthermore, systemic safety assessments confirmed no clinically significant coagulation abnormalities or adverse events. This method offers a safe, reproducible, and effective strategy for ensuring high-quality flap survival and favorable aesthetic outcomes in nasal reconstruction, avoiding the risks associated with systemic anticoagulation.

Introduction

Basal cell carcinoma (BCC) represents the most prevalent form of cutaneous malignancy worldwide, accounting for approximately 80% of all non-melanoma skin cancers. Its incidence has been steadily rising over the past few decades, posing a growing burden on global healthcare systems¹. The etiology of BCC is multifactorial, with cumulative exposure to ultraviolet (UV) radiation recognized as the primary environmental driver. Consequently, the tumor predominantly affects sun-exposed anatomical regions, particularly the head and neck. Beyond UV radiation, therapeutic ionizing radiation has also been identified as a significant risk factor; patients with a history of radiation therapy are at a heightened risk for developing basal cell and squamous cell carcinomas within the irradiated fields². Epidemiological studies further corroborate that the external nose, being the most prominent and exposed feature of the face, is the single most frequently affected site³.

Clinically, BCC is often characterized by an indolent growth pattern and an exceedingly low potential for distant metastasis, which can lead to a false sense of security among patients and clinicians⁴. However, specific histological subtypes exhibit aggressive biological behaviors. Studies have shown that tumors expressing markers such as alpha-smooth muscle actin are prone to deep local infiltration⁵. In the nasal region, the skin is thin and closely adherent to underlying structures. Neglected or high-risk lesions frequently exhibit “subclinical extension,” where microscopic tumor spread extends significantly beyond the clinically visible borders, infiltrating the subcutaneous fat, muscle fascia, and even the delicate nasal cartilage⁶. To ensure oncological clearance and prevent recurrence, radical surgical resection remains the gold standard of care. Comprehensive guidelines and long-term randomized clinical trials comparing various modalities have consistently demonstrated that surgical excision, whether via standard wide excision or Mohs micrographic surgery, offers superior cure rates compared to non-surgical interventions like cryotherapy or photodynamic therapy^7,8. Although Mohs surgery is widely considered the gold standard for high-risk nasal BCCs due to its maximal tissue preservation and superior margin control, standard wide local excision with a 5 mm margin was utilized in this specific cohort. This approach was chosen primarily due to institutional resource availability and specific patient preferences, particularly among elderly individuals unable to tolerate the prolonged duration of Mohs procedures. Regardless of the excision modality, the paramount objective is to achieve tumor-free margins; however, on the nose, this often necessitates the removal of substantial amounts of tissue, creating complex full-thickness defects that pose a formidable reconstructive challenge⁷.

Reconstructing nasal defects requires a meticulous balance between functional preservation (maintaining airway patency) and aesthetic restoration. The nose is the focal point of the face, and even minor asymmetries or scarring can be visually distracting. While skin grafting is a technically simple option for covering large defects, it often yields suboptimal results on the nose. Grafts frequently result in “patch-like” deformities due to discrepancies in color, texture, and thickness compared to the surrounding sebaceous nasal skin. Moreover, secondary contraction of grafts can distort the alar rim, resulting in functional impairment. Consequently, local flap transfer is the preferred method for nasal reconstruction⁹. The choice of flap depends heavily on the defect’s size and location. Traditional local flaps, such as the rhomboid, bilobed, and dorsal nasal flaps, are excellent for small-to-medium defects but are limited by tissue availability and may cause distortion of adjacent landmarks if stretched over larger areas¹⁰. For extensive defects, the paramedian forehead flap is considered the workhorse; however, it requires a two-stage procedure and leaves a conspicuous vertical scar on the forehead, which many patients find acceptable only as a last resort. Based on the outcomes observed in this clinical series, the nasolabial fold retrograde island flap combined with local heparin injection may be considered a preferred option for medium-to-large defects (approximately 2.5–4.5 cm) located on the mid-to-distal nose (dorsum, sidewall, and ala). This single-stage approach is particularly advantageous when the primary goal is to achieve superior texture matching while avoiding the significant donor site morbidity and staged surgical commitment associated with forehead flaps^9,10.

In this context, the nasolabial fold emerges as an ideal donor site. It provides a generous reservoir of mobile, non-hair-bearing skin that closely matches the color and texture of the nose. The donor site can be closed primarily within the natural nasolabial crease, rendering the postoperative scar virtually imperceptible¹¹. The nasolabial subcutaneous pedicle retrograde island flap is particularly versatile. Unlike traditional transposition flaps, it relies on a “retrograde” blood supply (often a random pattern or reverse flow from the distal branches of the angular and facial arteries), allowing it to reach the distal nose and ala effectively¹¹. However, this unique vascular anatomy is also its “Achilles’ heel.” The flap’s survival depends on a delicate subcutaneous pedicle that must be rotated up to 180°. This torsion can mechanically compress the vascular channels. Physiologically, veins have thinner walls and lower intraluminal pressure than arteries; thus, even mild twisting or postoperative edema can collapse the venous outflow tract while arterial inflow persists. This hemodynamic imbalance leads to venous congestion, a critical complication where blood enters the flap but cannot escape.

Venous congestion is widely regarded as more detrimental to flap survival than arterial insufficiency. Persistent stasis increases hydrostatic pressure within the capillary bed, forcing fluid into the interstitial space and causing severe edema. This swelling further compresses the microvasculature, creating a vicious cycle of ischemia, hypoxia, and eventually, necrosis. At the microcirculatory level, stasis promotes platelet aggregation and microthrombus formation, leading to the “no-reflow” phenomenon. Current salvage strategies for congested flaps, such as systemic anticoagulants or leeches, carry risks of systemic bleeding or infection. This study proposes a novel, targeted intervention: the immediate local micro-injection of heparin sodium. Pharmacologically, high local concentrations of heparin prevent microthrombosis within the compromised vascular bed. Mechanically, the needle puncture sites create artificial outflow tracts, allowing controlled oozing that physically decompresses the flap and reduces venous load until the native drainage system equilibrates.

Despite the theoretical benefits, standardized protocols for this technique are lacking. This study aims to evaluate the clinical efficacy of combining the nasolabial retrograde island flap with a rigorous postoperative local heparin sodium injection protocol. By analyzing outcomes in 24 patients, we assess the impact of this method on flap perfusion, survival quality, and aesthetic results, offering a refined solution for high-risk nasal reconstruction.

Protocol

The study protocol was conducted in strict accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Wuxi No.2 People’s Hospital (Approval number: 2024Y-155). All patients provided written informed consent for both the surgery and the publication of their medical images.

1. Patient selection and preparation

1. Inclusion criteria: Select patients with pathologically confirmed basal cell carcinoma (BCC) of the external nose who require surgical excision and flap reconstruction.
2. Pre-operative assessment: Perform a comprehensive physical examination and assess the size, location, and depth of the tumor. Evaluate the laxity of the skin at the donor site (nasolabial fold).
3. Exclusion criteria: Exclude patients with distant metastasis, severe systemic coagulation disorders, uncontrolled hypertension, or other surgical contraindications (Figure 1).
4. Patient positioning: Place the patient in a supine position. Clean the surgical site with a standard iodophor disinfectant, then drape it with sterile towels.
5. Anesthesia: Administer local infiltration anesthesia around the tumor and the nasolabial fold donor site using 2% lidocaine injection.

2. Tumor excision

1. Marking: Mark the tumor excision boundaries with a surgical marking pen, ensuring a 5 mm safety margin from the visible edge of the lesion.
2. Excision: Use a standard No. 11 surgical blade to excise the tumor and the surrounding 5 mm of normal tissue down to the deep subcutaneous layer or perichondrium to ensure tumor-free margins.
3. Hemostasis: Achieve rigorous hemostasis using electrocoagulation.

3. Flap design and harvesting (Retrograde Island Flap)

1. Design: Design a fusiform or leaf-shaped skin flap along the ipsilateral nasolabial fold. The size of the flap should match the defect size (ranging from approximately 2.0 cm × 1.6 cm to 4.2 cm × 4.6 cm).
2. Incision: Incise the skin and subcutaneous tissue along the design lines using a No. 11 surgical blade. Ensure the incision length corresponds to the intended flap length (ranging from 2.6 to 4.5 cm).
3. Flap Dissection: Dissect the flap from the distal end (near the oral commissure) towards the proximal end (alar base).
4. Pedicle Preservation: Preserve a subcutaneous tissue pedicle at the proximal end (near the nasal alar) to maintain the retrograde blood supply from the angular and facial artery branches. Do not skeletonize the vascular pedicle; retain a wide base of sufficient subcutaneous fat to ensure venous drainage. During dissection, rigorously ensure the pedicle is not thinned out excessively to avoid compromising the micro-vascular network (See Figure 2A).
5. Tunneling/Transfer: Loosen the tissue between the pedicle and the defect to create a subcutaneous tunnel or rotation arc.

4. Flap transfer and suturing

1. Transfer: Rotate the island flap approximately 180 around the pedicle pivot point to cover the nasal defect without excessive tension. Critically, observe the pedicle during rotation to ensure there is no kinking, sharp torsion angles greater than 180, or external compression from the edges of the skin tunnel, as this will immediately compromise the fragile venous outflow.
2. Donor site closure: Undermine the wound edges of the nasolabial donor site and close it directly in layers to hide the scar within the nasolabial fold.
3. Flap fixation: Suture the flap to the recipient site edges using 6–0 non-absorbable surgical sutures. Ensure precise alignment of the skin edges(See Figure 2B).

5. Local Heparin Sodium injection protocol

Note: This is the critical intervention for preventing venous congestion.

1. Preparation: Withdraw standard Heparin Sodium Injection fluid (e.g., 12,500 units/2 mL or similar standard concentration) using a 5 mL disposable syringe.
2. Immediate post-operative injection: Immediately after suturing, perform local micro-injections into the flap.
3. Injection Technique: Insert the needle into the deep dermal and subdermal plexus layers of the flap. Adopt a multi-point injection pattern (Grid pattern) to ensure uniform fluid distribution across the entire flap surface. Administer approximately 1–2 drops of heparin sodium per 0.5 cm² of flap surface area(See Figure 2C).
4. Endpoint: Continue the micro-injections until the flap color transitions from dark red/pale to a healthy pale pink, indicating improved microcirculation. Note: The determination of this endpoint currently relies on the surgeon’s subjective post-operative visual clinical judgment (color transition and a normalized capillary refill time of 1–2 s), rather than on automated objective perfusion-monitoring devices.

6. Post-operative care and monitoring

1. Dressing: Cover the incision with sterile petrolatum gauze and apply medical sterile gauze. Apply a pressure dressing to the wound area.
2. Medication: Administer routine antibiotic prophylaxis and anti-inflammatory treatment.
3. Post-operative Heparin maintenance: Monitor the flap daily for signs of venous congestion (dark purple color, swelling). Administration does not follow a fixed schedule for all patients; it is based solely on daily clinical observation. If congestion is observed, repeat the local heparin sodium micro-injection (same dosage: 1–2 drops/0.5 cm²) once daily until the flap color stabilizes to light pink (typically requiring 3 to 7 days of intervention).
4. Safety considerations and bleeding management: Due to the use of local anticoagulants, monitor the puncture sites and the donor site closely for excessive bleeding or hematoma formation. If continuous or excessive oozing occurs, temporarily halt the heparin injections and apply mild, intermittent external pressure. Ensure this protocol is strictly avoided in patients with known severe systemic coagulopathies.
5. Monitoring metrics: Assess flap color (Red/Pale/Dark Purple), temperature, swelling, and capillary refill time daily. Monitor wound exudation/bleeding.
6. Safety check: Perform blood routine and coagulation function tests (platelet count, prothrombin time (PT), and activated partial thromboplastin time (APTT)) one week post-operatively to exclude systemic coagulation abnormalities.
7. Follow-up: Remove sutures at 7 days post-operatively. Evaluate the final aesthetic outcome (scarring, texture, color match) at 1 month and 3 months.

Results

Patient demographics and clinical characteristics

A total of 24 patients with nasal basal cell carcinoma (BCC) were enrolled in this study between June 2024 and June 2025. The cohort consisted of 14 males and 10 females, with a mean age of 72.0 years ± 12.8 years (range: 50–94 years). The tumor locations were primarily on the nasal dorsum (n = 15), followed by the nasal ala (n = 5) and nasal tip (n = 4). Detailed demographic and baseline characteristics are summarized in

Discussion

BCC represents a significant and growing public health challenge, accounting for most cutaneous malignancies worldwide. Epidemiological trends over the past decade have demonstrated a consistent rise in incidence, particularly among aging populations with a history of cumulative ultraviolet radiation exposure^12,13. The external nose, serving as the central aesthetic unit of the face, is disproportionately affected, hosting a high frequency of these lesions due to...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Heparin Sodium Injection	Tianjin Biochem Pharmaceutical Co., Ltd. (Tianjin, China)	H12020511	Core intervention for preventing venous congestion
Iodophor	Shanghai Likang Disinfection High-Tech Co., Ltd. (Shanghai, China)	No. 0001	For surgical site disinfection
Lidocaine injection	Hebei Tiancheng Pharmaceutical Co., Ltd. (Cangzhou, China)	H13022313	For local infiltration anesthesia
No. 11 surgical blade	Shanghai Pudong Jinhwan Medical Supplies Co., Ltd. (Shanghai, China)	20212020377	For tumor excision and flap harvesting
6-0 Non-absorbable Surgical Suture	Jiahe Medical Materials Co., Ltd. (Suzhou, China)	20162020017	For flap fixation and skin closure
Sterile petrolatum Gauze	Zhende Medical Products Co., Ltd. (Shaoxing, China)	20163141626	For initial incision dressing
Medical sterile gauze	Xuchang Zhende Medical Dressing Co., Ltd. (Xuchang, China)	20172140450	For pressure dressing