The surgical management and outcomes of kissing nevi of the eyelids

Abstract

Purpose

To describe the clinical characteristics, surgical technique, and outcomes in patients with kissing nevi who underwent surgical management in two tertiary referral centers.

Methods

Medical chart review was conducted for all patients who underwent surgical repair in Moorfields Eye Hospital and The Children’s Hospital of Philadelphia. Demographics, medical history, lesion characteristics, surgical intervention, and outcomes were collected. Main outcome measures were surgical interventions as well as functional and cosmetic outcomes.

Results

Thirteen patients were included. Mean age at presentation was 23.46 years (±19.35,4–61), and the mean number of surgeries per patients was 1.9 (±1.3,1–5). Initial procedure included incisional biopsy in three cases (23%) and complete excision and reconstruction in 10 cases (77%). Surgery involved the upper and lower anterior lamella in all cases, the upper posterior lamella in 4 patients (31%), and the lower posterior lamella in 2 patients (15%). Local flaps were utilized in 3 cases and grafts in 5 cases. Complications included: trichiasis (n = 2, 15%), lower eyelid ectropion (n = 2, 15%), mild ptosis (n = 1, 8%), and upper/lower punctal ectropion (n = 1, 8%). Twelve patients (92%) were satisfied with the final functional and cosmetic outcome. No recurrence or malignant transformation were observed in any patient.

Conclusion

The surgical management of kissing nevi can be challenging, and commonly includes the use of local flaps or grafts, often requiring multiple interventions. The approach should be based on lesion size and location, proximity and involvement of key anatomical landmarks, as well as individual facial characteristics. Surgical management has a favorable functional and cosmetic outcome in the majority of patients.

Introduction

Kissing nevus of the eyelids, also known as divided naevi, panda nevus or split ocular nevus, is a rare dermatological congenital abnormality [1]. It was first described in 1919 by Fuchs as an interesting embryological phenomenon [2]. Congenital divided nevus has also been described in the penis [3] and between fingers [4], however this is much less common than the eyelids [5].

In embryological studies it was found that the palpebral buds (preliminary eyelids) develop during the 7th week of gestation above and below the cornea [6]. By the 9th to 10th gestational week, the two eyelids meet and the epidermal layer fuses. During the 20th week, the eyelids begin to separate, with complete separation occurring at 28–30 weeks [6]. The assumption is that the kissing nevus is created between the 9th and 20th weeks of gestation when melanocytes originating from the neural crest migrate to the undersurface of the embryonic epidermis of the scalp and face and proliferate to a single nevus [6]. The nevus is divided when the lids separate. The nevus appear to “kiss” on closure of the lids- appearing as one [6].

Kissing nevi are commonly an isolated disorder, not associated with other medical problems or malignant nevus in other areas in the body; however, an early systemic medical evaluation is mandatory due to the wide differential diagnosis. This includes neurofibromas, epitheliomas, tuberculomas and syphilides [7].

A kissing nevus can cause congenital ptosis, ectropion, trichiasis, epiphora, or even amblyopia [8], and the esthetic appearance becomes increasingly troublesome during the teenage years and adulthood [8], all of these reasons being an indication for treatment [9]. Management includes non-surgical treatments such as laser therapy, cryotherapy and dermabrasion when it is limited to the superficial dermis, as well as surgery [5]. The purpose of the current study is to describe the clinical characteristics, surgical treatment and prognosis of patients with kissing nevus who underwent surgical treatment in two tertiary referral centers.

Methods

Patients and data

All patients who had been diagnosed with eyelids kissing nevi and underwent surgical repair in Moorfields Eye Hospital, London, United Kingdom or The Children’s Hospital of Philadelphia (CHOP), Philadelphia, Pennsylvania, U.S.A. over a 15 year period between January 2006 and March 2021 were included. The following parameters were retrieved from the medical database and analyzed: patient demographics, ocular and medical history, laterality and location of the condition, clinical presentation, type of surgical intervention, and final outcome. Descriptive statistical analyses were carried out using Microsoft Excel (Microsoft, Redmond, WA, USA).

The study was approved by the local Institutional Review Boards of Moorfields and CHOP and adhered to the tenets of the Declaration of Helsinki.

Results

Demographics

Thirteen patients (6 males; 7 females) were included, with a mean age at presentation of 23.46 years (±19.35,4–61). Additional ocular disorders included high myopia with refractive amblyopia in one patient; none of the patients had family history of a kissing nevus. Systemic disorders included a urological disorder requiring a nephrectomy at childhood in one patient. The mean time of follow up was 244.59 months (±455.43, 3–646).

Nevus characteristics

Six patients (46.2%) had a medial canthal nevus, six (46.2%) had a lateral canthal nevus and one (7.6%) had a central eyelid nevus extending to the majority of the eyelid length, but not involving the canthi. In all cases, the lesion involved the anterior lamella of the upper and lower eyelids. Two patients (15.4%) had additional noticeable nevi on the head and neck in childhood: one on the bulbar conjunctiva extending to the temporal cornea and one on the left cheek. Nevi characteristics are summarized in Table 1.

Table 1.

Nevus characteristics.

Nevus characteristics	Number	Percent
Nevus side
Right	6	46%
Left	7	54%
Visual Acuity (LogMAR, Mean ± SD, Range)	0.095 ± 0.19 (0.0–0.5)
Diameter of Nevus (mm)
Upper eyelids	11.5 ± 5.2 (4–20)
Lower eyelids	10.5 ± 6.4 (2–20)
Color-
Brown	11	85%
Gray	1	8%
Black	1	8%
Amelanotic	0	0%
Type of lesion
Flat	1	8%
Elevated	8	61%
Dome-shaped	4	31%
Pedunculated	0	0%

Surgical intervention

The mean age at first surgery was 23.7 years (±19.6, 4–61). The mean number of surgeries per patient was 1.92 (±1.32, 1–5) during the follow-up period of 244.59 months (±455.43, 3–646). All surgeries were under general anesthetic or sedation. The main reason for surgery in all patients was to improve esthetic appearance. In all patients, the surgery involved the upper and lower anterior lamella. In four patients (30.1%) the surgery involved the upper posterior lamella, and in two patients (15%) the lower posterior lamella.

The initial intervention included incisional biopsy in three patients (23%) (to make sure that there is no malignant transformation). None of them had a second surgery. Ten patients (77%) underwent anterior and posterior eyelid reconstruction by different methods:

Two patients (15%) had direct closure of the anterior lamella of the upper and lower eyelids, while one patient (8%) had direct closure of the upper eyelid anterior and posterior lamella as well as direct closure of lower anterior lamella.

Three patients (24%) underwent canthoplasty and periosteal flap creation followed by canthal reconstruction for lower posterior lamella reconstruction, as well as direct closure of the anterior lamella of the upper and lower eyelids.

Four patients (31%) had a reconstructive surgery utilizing a graft: two free tarsal grafts for upper eyelid posterior lamella reconstruction and two retro-auricular skin grafts for upper eyelid anterior lamella reconstruction (Figs. 1, 2, and 3).

Fig. 1. A 21-year-old lady who has a “Kissing nevus” since birth.

The upper lid is cosmetically relatively acceptable, but the lower lid nevus is densely pigmented with involvement of the posterior lamella (A, B). The lower eyelid nevus was excised from the lower anterior lamella. It was reconstructed with skin graft taken from the post-auricular skin with a good cosmetic result (C, D).

Fig. 2. At the age of 4, this patient had extensive involvement of the lids by a congenital nevus.

A, B The patient had excision and skin grafting procedures, but nevus remained at the lid margins (C). The lid margin nevus was resected because of suspicious areas of black pigmentation. The specimen from the upper lid is positioned for pathology. The lesion was read as benign (D). The upper lid is repaired with a free tarsoconjunctival graft with a skin flap from the upper lid. The lower lid margin is left open to heal after the lid margin nevus was contoured using a Colorado cauter (E,F). A good cosmetic result was at the end of follow up (G).

Fig. 3. A 5-year-old patient with temporal kissing nevus that underwent reconstruction using skin graft and local advancement flap.

A 5-year-old patient with left temporal kissing nevus (A, B). The nevus was excised from the upper and lower anterior lamella and lid margin (C). The upper eyelid defect was reconstructed using skin graft taken from the ipsilateral upper eyelid, and the lower defect using local advancement flap from cheek (D, E). (F).

Outcome

Postoperative complications included: trichiasis of patients who underwent excision of the lesion without graft or flap (n = 2, 15%), mild lower eyelid ectropion of patient who underwent excision of the lesion with skin graft (n = 1, 8%), lower lid retraction of patient who underwent excision of the lesion with skin flap (n = 1, 8%) (Fig. 2), and upper/lower punctal ectropion of patient who underwent excision of the lesion with skin graft (n = 1, 8%).

At the end of follow-up, twelve patients (92%) were satisfied with the cosmetic result, while one patient (8%) was unsatisfied due to mild residual ptosis that he had also before (but was improved after the surgery). None of the patients had lesion recurrence or malignant transformation.

Discussion

Kissing nevus of the eyelid is a rare phenomenon, with only a few case reports and small cases series reported in the literature to date [10–12]. In this series, we present 13 cases of kissing nevi that underwent surgical repairs. Surgical techniques were diverse and included the use of flaps and grafts for reconstruction. In all cases the reconstruction involved the anterior lamella of the upper and lower eyelids, while in less than a half the posterior lamella was involved. At the end of follow-up, none of the patients had malignant transformation and almost all were satisfied with the cosmetic result. To the best of our knowledge, this is one of the largest reported series of kissing nevi to date.

Although kissing nevus is a congenital disorder [5], the patients in this series presented only in their late childhood to adulthood. This may be attributed to delayed referral to tertiary centers due to the lack of a functional ophthalmic disorder (such as amblyopia), as well as the increased emphasis on cosmetic appearance as the child grows. In this series, the surgical indication was esthetic in all cases, and this, together with the age of presentation, is in accordance with previous reports [13, 14]. However, since kissing nevi can also cause deprivational or refractive amblyopia due to ptosis [1, 15, 16], patients may require early intervention, and a comprehensive ophthalmic examination is recommended in all kissing nevi cases soon after birth.

Historically, two classification systems were used to evaluate kissing nevi. The first is based on nevus size: (a) small (less than 1.5 cm in diameter), (b) medium (1.5–20 cm in diameter) and (c) large (greater than 20 cm in diameter) [5]. The second refers to the histological type (melano-cystic, cellular or compound) [5]. According to the first classification, one of our patients had a large nevus. In the literature, it was reported that patients with large nevi are at higher risk for malignant transformation and may need to be followed up closely [17, 18]. However, in our case series, no malignant transformations were observed in the long follow up period of more than 20 years. McDonnel et al. reported that the average risk of malignancy is 14% for a whole lifetime in large nevi [16]. However, in Desai et al’s literature review of 149 cases in 23 papers, no cases of malignant transformation were observed [5]. Therefore, the risk of malignant transformation is very low and probably does not require any long-term management other than that practiced in common nevi.

Two main surgical approaches are reviewed in the literature. The first technique involves a single-staged lesion removal with immediate reconstruction [14]. The second surgical approach includes a staged procedure of multiple lesion removals followed by possible reconstruction at a later stage. The later approach allows observation for recurrence in high-risk cases as well as minimizes the surgical defect in each intervention; for example – allowing for multiple successive primary closures instead of the use of large skin grafts in extensive primary excisions [13]. In this series, most of the patients underwent a single-staged procedure. This approach has several advantages. First, a single-staged procedure that includes complete excision may be critical to avoid re-growth and the need for further surgical procedures. This was demonstrated in Wu-Chen et al’s case, in which a patient underwent incomplete excision of a dermal kissing nevus at age 6 [19]. Several years later the patient had significant regrowth of the lesion with suspicion of malignancy [19]. Second, in contrast to other eyelid lesions such as squamous cell carcinoma and sebaceous cell carcinoma, the diagnosis of non-malignant congenital kissing nevus is clinical, thus histopathological analysis should not withhold reconstruction [1]. Third, multiple surgeries as well as multiple anesthesia may be associated with adverse potential surgical and neurotoxic side effects, even more so in young children [20]. The economic impact may also be taken into consideration, with multiple surgeries requiring resources such as physicians’ availability, theater time and instruments, and longer waiting periods for other patients. Therefore, it seems that a single-staged surgery, as presented in this series, may be beneficial in most cases.

Kissing nevi, involving the anterior lamella of both eyelids, can also involve the upper and/or posterior lamella [15], and surgery requires meticulous reconstruction of all lamellae. In our series, the surgery involved the anterior lamella of the upper and the lower eyelids in all cases, while a graft was needed only in two cases. In less than half of the cases, the surgery involved the posterior lamella, while in a third of them, the reconstruction required a free tarsal graft. In our series, post-surgical eyelid malposition has only occurred in cases that the surgical intervention involved the posterior lamella. Therefore, posterior lamella surgery should be reserved for cases that require such intervention, mandating a careful, minimal excision and optimal reconstruction. A careful consideration should be applied to the mucocutaneous junction and the eyelashes. In some cases, post-surgical madarosis was observed, which may be a major drawback on cosmetic outcome. Meticulous pigment removal around the eyelash’s follicles with the assistance of an operating room microscope may minimize follicle destruction. Alternatively, in cases of mild pigmentary changes around the follicles, a ‘laissez faire’ approach may be reasonable approach in certain individuals.

In conclusion, we present a large series of patients with kissing nevi of the eyelid who underwent surgical repair. The indication was esthetic, rather than functional, in all cases, the patients were satisfied with the surgical outcome, and no recurrence or malignant transformation was observed. The removal and reconstruction can mostly be performed in a single-staged procedure that involves the posterior lamella in the minority of cases. The reconstruction should be personalized to each patient according to the lesion size and anatomical structures involved. The use of a microscope in the operating room is recommended for lesion removal in the eyelashes’ area. Personalized surgery for young patients, with careful attention to the posterior lamella provide good long-term functional and esthetic outcomes.

Summary table

What was known before

• Kissing nevus of the eyelids is a rare dermatological congenital abnormality. A kissing nevus can cause congenital ptosis, ectropion, trichiasis, epiphora, or even amblyopia, and the esthetic appearance becomes increasingly troublesome during the teenage years and adulthood all of these reasons being an indication for treatment.

What this study adds

• Surgical techniques for kissing nevus are diverse and included the use of flaps and grafts for reconstruction. In all cases the reconstruction involved the anterior lamella of the upper and lower eyelids, while in less than a half the posterior lamella was involved. None of the patients had malignant transformation and almost all were satisfied with the cosmetic result.

Author contributions

OZ: Conception or design of the work, Data collection, Data analysis and interpretation, Drafting the article, Critical revision of the article, Final approval of the version to be published. DL: Data collection, Data analysis and interpretation, Critical revision of the article, Final approval of the version to be published. JAK: Critical revision of the article, Final approval of the version to be published. WRK: Critical revision of the article, Final approval of the version to be published. GBS: Critical revision of the article, Final approval of the version to be published. DHV: Conception or design of the work, Data collection, Critical revision of the article.

Competing interests

The authors declare no competing interests.