Grade I
Diameter less than 5 mm: Superficial and confined to the limbus.
Depth of invasion: Limited to about half of the corneal stroma.
Corneal Dermoid (Limbal Dermoid)
Key Points at a Glance
Section titled “Key Points at a Glance”1. What is Corneal Dermoid?
Section titled “1. What is Corneal Dermoid?”Corneal dermoid is a congenital benign tumor that occurs on the cornea, limbus, or conjunctiva. It is a choristoma in which skin tissue aberrantly proliferates in the corneoconjunctival area, also called limbal dermoid. A choristoma is a tumor composed of normal tissue growing in an ectopic location.
The incidence in newborns is 1–3 per 10,000, accounting for 25% of congenital orbital lesions 2). Limbal dermoid is the most common type, typically occurring at the inferotemporal limbus. It is usually unilateral and occurs sporadically without heredity. Its size generally does not change after birth. Diameter ranges from 3 mm to as large as 10 mm.
Corneal dermoid and orbital dermoid cyst are completely different diseases and should not be confused.
Q
Can corneal dermoid become malignant?
A
Corneal dermoid is a congenital benign tumor (choristoma) with no reports of malignant transformation. It is a non-proliferative lesion that generally does not change in size after birth. However, it may cause amblyopia or cosmetic issues, so regular follow-up is important.
2. Main Symptoms and Clinical Findings
Section titled “2. Main Symptoms and Clinical Findings”
Jinho Jeong, Gabriel M Rand, Ju-Yeun Lee, Ji-Won Kwon Novel limbal dermoid surgery for visual acuity and cosmesis improvement: A 7-year retrospective review 2023 Jun 2 PLoS One. 2023 Jun 2; 18(6):e0286250 Figure 4. PMCID: PMC10237392. License: CC BY.
The black asterisk indicates corneal opacity, and the white asterisk indicates conjunctival keratinization with neovascularization. The irregular surface and surrounding conjunctival changes after excision of the corneal dermoid are visible.
Subjective Symptoms
Section titled “Subjective Symptoms”- Decreased visual acuity: Due to astigmatism and resulting amblyopia. Large lesions may also block the visual axis.
- Foreign body sensation: Caused by keratinization or elevation of the tumor surface.
- Cosmetic concerns: The white tumor may be noticeable in appearance.
Clinical Findings
Section titled “Clinical Findings”Corneal dermoid is a well-demarcated, white, hemispherical, solid tumor that commonly occurs at the inferotemporal limbus. It appears milky white to light brown and may have hairs on its surface. The dermoid surface is keratinized like skin, causing tears to be repelled.
Oblique astigmatism and anisometropic amblyopia are present in about two-thirds of cases. Bilateral involvement is seen in 10–25% of all ocular surface dermoids5).
Based on clinical and AS-OCT findings, they are classified into three grades5).
Grade II
Large lesion: Covers most of the cornea and extends to just anterior to Descemet’s membrane in the deep stroma.
Characteristic: Does not involve Descemet’s membrane itself.
Grade III
Most severe: Covers the entire cornea and penetrates from the anterior surface of the eyeball to the iris pigment epithelium.
Frequency: The rarest type.
3. Causes and Risk Factors
Section titled “3. Causes and Risk Factors”Corneal dermoid results from abnormal development of the first and second branchial arches during embryonic life. Dysplasia of the ectoderm that forms the cornea and conjunctiva causes skin tissue to become misplaced into the corneoconjunctiva, forming a dermoid. Most cases are sporadic, but it can occur in association with the following syndromes.
Goldenhar Syndrome (Oculo-auriculo-vertebral Spectrum)
Section titled “Goldenhar Syndrome (Oculo-auriculo-vertebral Spectrum)”A syndrome in which limbal dermoid is accompanied by accessory ears, ear pits, mandibular hypoplasia, and vertebral anomalies, occurring in 1 in 3,000–5,000 births with a male-to-female ratio of 3:2 1). Most cases are sporadic. Maternal diabetes, hypertension, viral infections (influenza, rubella), and exposure to cocaine, tamoxifen, or retinoic acid have been reported as predisposing factors 1).
When limbal dermoid is found, systemic examination should be performed to check for the presence of Goldenhar syndrome.
Other Associated Syndromes
Section titled “Other Associated Syndromes”- Ring dermoid syndrome: A rare autosomal dominant disorder characterized by bilateral annular limbal dermoids. Associated with mutations in the PITX2 gene.
- Epidermal nevus syndrome: A group of rare disorders involving epidermal nevi of the skin and abnormalities of the brain, eyes, and skeletal system.
Q
What is the relationship with Goldenhar syndrome?
A
Corneal dermoid (limbal dermoid) can be an ocular finding of Goldenhar syndrome. Goldenhar syndrome is a congenital disorder accompanied by accessory ears, ear pits, mandibular hypoplasia, and vertebral anomalies, occurring in 1 in 3,000–5,000 births 1). When limbal dermoid is found, it is important to perform systemic examination to confirm these associations.
4. Diagnosis and Examination Methods
Section titled “4. Diagnosis and Examination Methods”Clinical Diagnosis
Section titled “Clinical Diagnosis”The diagnosis of corneal dermoid is primarily based on clinical findings, and biopsy is generally not required. If a resected specimen is available, histopathological examination can confirm the diagnosis.
Examination Methods
Section titled “Examination Methods”- Slit-lamp microscopy: Confirms a well-demarcated, white, hemispherical, solid mass. Observe the presence of hair and neovascularization on the surface.
- Anterior segment optical coherence tomography (AS-OCT): Non-invasively evaluates the depth of the lesion and involvement of Descemet’s membrane 5). It is also useful for grade classification.
- Ultrasound biomicroscopy (UBM): Used to assess lesion depth, but visualization of Descemet’s membrane may be difficult due to strong acoustic attenuation from the dermoid.
- Cycloplegic refraction: Essential for evaluating astigmatism and anisometropic amblyopia.
- Digital photography documentation: Tracks changes in lesion size over time.
Systemic Evaluation
Section titled “Systemic Evaluation”If Goldenhar syndrome is suspected, multidisciplinary evaluation including otolaryngology and pediatrics should be performed. Hearing tests, head CT, spinal X-rays, and cardiac/renal ultrasound are recommended 1).
Differential Diagnosis
Section titled “Differential Diagnosis”- Dermoid cyst: Dermoids are solid, whereas dermoid cysts are cystic and contain secretions.
- Peters anomaly: Congenital central corneal opacity with iris and lens adhesions.
- Sclerocornea: A congenital anomaly where the cornea appears white and opaque like the sclera.
- Pterygium: An acquired fibrovascular proliferation typically located on the nasal side.
- Corneal scar: history of trauma or infection
5. Standard Treatment
Section titled “5. Standard Treatment”Amblyopia Treatment (Highest Priority)
Section titled “Amblyopia Treatment (Highest Priority)”The most important aspect of corneal dermoid is the prevention and treatment of amblyopia. Surgery does not improve astigmatism and therefore does not treat amblyopia. It is necessary to start amblyopia treatment with refractive correction (glasses) and occlusion of the healthy eye before surgery.
Conservative Management (Grade I)
Section titled “Conservative Management (Grade I)”For Grade I dermoids with astigmatism less than 1D and minimal surface irregularity, conservative observation is appropriate. Regular examinations should be performed every 6 to 12 months, evaluating visual acuity, lesion size, and cycloplegic refraction.
Surgical Treatment
Section titled “Surgical Treatment”Surgery is primarily cosmetic, and early surgery is generally not indicated. Surgery is considered in the following cases:
- Amblyopia unresponsive to conservative management
- Invasion of the pupillary area or optical zone
- Surface decompensation with corneal dellen (thinning)
- Chronic ocular irritation or recurrent conjunctivitis
- Aesthetic considerations
The surgical procedure is selected according to the grade.
| Grade | Recommended Procedure |
|---|---|
| Grade I (superficial) | Excision + superficial keratectomy |
| Grade II | Deep anterior lamellar keratoplasty (DALK) ± amniotic membrane transplantation |
| Grade III | Total anterior segment reconstruction |
Key points of superficial keratectomy
Section titled “Key points of superficial keratectomy”Superficial keratectomy is performed after tumor excision. Simple excision alone frequently leads to recurrence or pseudopterygium. The graft does not need to be fresh cornea; frozen preserved cornea is acceptable. The trephine diameter is usually about 7.0 mm. Suturing is performed with 10-0 nylon interrupted sutures, approximately 12 stitches. Since residual tumor can cause severe postoperative inflammation and pseudopterygium, complete excision should be aimed for.
Abdulmannan et al. (2022) reported the management outcomes of 5 cases of limbal dermoid in infants and children. Astigmatism of 1D or more was observed in 4 cases, but astigmatism did not improve after surgery, and visual improvement was mainly due to spectacle use and occlusion of the healthy eye 6).
Q
Will surgery cure astigmatism?
A
Removing the dermoid by surgery does not improve astigmatism. Surgery is for cosmetic purposes and does not treat amblyopia. For astigmatic amblyopia, refractive correction with glasses and occlusion therapy of the healthy eye are necessary. It has been reported that astigmatism does not change or tends to increase slightly after surgery 6).
Q
When is the best time for surgery?
A
Surgery for corneal dermoid is for cosmetic purposes, and in principle, there is no indication for early surgery. Dermoids covering the pupillary area require early surgery, but if they are confined to the limbus and not enlarging, surgery can be performed after infancy. Surgery at a young age requires general anesthesia.
6. Pathophysiology and Detailed Pathogenesis
Section titled “6. Pathophysiology and Detailed Pathogenesis”Several hypotheses exist regarding the pathogenesis of corneal dermoid. One theory suggests that it arises from metaplastic changes in mesodermal cells between the optic cup rim and surface ectoderm during early development. Another proposes sequestration of pluripotent cells during embryonic development of surrounding ocular structures.
As a choristoma, a dermoid is composed of ectodermal tissues such as hair, skin, and rarely teeth, along with mesodermal tissues such as adipose tissue and cartilage. Histologically, it shows structures resembling epidermis and dermis containing collagenous connective tissue, hair follicles, and sebaceous glands.
The dermoid tissue itself has no proliferative activity.
Mitamura et al. (2021) reported a pterygium-like growth containing residual dermoid tissue in a 79-year-old Japanese woman who underwent limbal dermoid resection at age 12. Immunohistochemistry showed Ki67 (cell proliferation marker) positivity in pterygium epithelial cells and neovascular endothelial cells, but negativity in dermoid components (adipose tissue, connective tissue, peripheral nerves) 3). Although residual dermoid tissue after incomplete resection lacks proliferative capacity, it may act as a modifying factor for pterygium development.
This report supports the importance of complete resection and reaffirms that dermoid tissue itself is a congenital, non-proliferative lesion.
7. Latest Research and Future Perspectives
Section titled “7. Latest Research and Future Perspectives”Development of New Surgical Techniques
Section titled “Development of New Surgical Techniques”Poddi et al. (2025) reported a technique for Grade I limbal dermoid involving excision followed by mitomycin C (0.02%) application and triple-layer amniotic membrane transplantation fixed with fibrin glue. In an 18-year-old female, no recurrence was observed over 2 years of follow-up, with corneal topographic regularization, reduction in higher-order aberrations, and improvement in BCVA 2).
For a giant corneal and ocular surface dermoid (17×14 mm), Choudhary et al. (2021) reported a combined technique of pre-descemetic DALK (deep anterior lamellar keratoplasty) and SLET (simple limbal epithelial transfer) from the contralateral eye. Satisfactory cosmetic results were achieved while preventing pseudopterygium formation 4).
Lamellar keratoplasty using lenticules extracted from SMILE surgery has also been reported, attracting attention as a technique that does not require donor corneas.
Genetic Research
Section titled “Genetic Research”Fu et al. (2024) performed whole exome sequencing (WES) on a 4-year-old boy with Goldenhar syndrome and identified five gene mutations (PRDM16, FAT4, POLR1C, PLEC, MED12) potentially associated with microtia 1). Elucidating the genetic basis of Goldenhar syndrome may contribute to future diagnosis and prevention.
8. References
Section titled “8. References”
- Fu Y, Yu H, Zhang J, Zhou N. Goldenhar syndrome with limbal neoformation, microtia and skeletal deformities: a case report and literature review. BMC Ophthalmol. 2024;24:81.
- Poddi M, Romano V, Borgia A, et al. Combined Multilayered Amniotic Membrane Graft and Fibrin Glue as a Surgical Management of Limbal Dermoid Cyst. J Clin Med. 2025;14:607.
- Mitamura M, Kase S, Ohguchi T, Ishida S. A case of pterygium-like proliferation containing postoperative limbal dermoid remnants: a clinicopathological study. BMC Ophthalmol. 2021;21:12.
- Juneja A, Puthalath AS, Gupta N, Verma PK. Isolated bilateral limbal dermoid, preauricular skin tags and ametropic amblyopia. BMJ Case Rep. 2021;14:e245078.
- Abdulmannan DM. Successful Management of Limbal Dermoid in Infancy and Childhood: A Case Series. Cureus. 2022;14(3):e22835.