Osteoma Cutis (Nevus of Nanta) of the Eyebrow

Abstract

There have been various modifications in traditional evisceration technique to provide better cosmetic and functional outcome to the patient. Smith et al. 1 retrospectively reviewed the 201 cases which had undergone evisceration by the "2 scleral flaps" technique. They concluded that this technique is a simple, safe, and useful procedure that enables the placement of adequately sized implants. However, their study lacks a few important things. First, the authors have not adequately analyzed the motility of the implant and prosthesis. Though all patients were pleased with their cosmetic result after prosthesis fitting, the objective assessment of motility was not carried out. Moreover, postoperative motility depends upon various factors depending upon each case. For example, cases with trauma and retinal detachment (with scleral buckling) may not have adequate preoperative motility, and these accounted for the majority of cases (130 out of 201 cases) in the study. We believe that postoperative motility in such cases may not be adequate when compared to other cases.Secondly, the "2 scleral flaps" technique involves sclerotomy from the limbus to the optic nerve in 2 quadrants, after which flaps are released from the optic nerve. This would cause more disturbances of the orbital tissue, suspensory ligament, and physiologic dynamics of muscle. We know that the rectus muscles pass through the connective tissue sleeves or pulleys, located close to the equator of the globe, which stabilizes the position of the recti relative to the orbit during eye movements. These pulleys are dependent upon the intermuscular septum and Tenon's fascia for their support and are believed to be the functional origin of the muscle. So when scleral flaps are made, damage to this important structure is bound to occur, especially in trauma and retinal detachment, where they are already compromised. This is also reflected in the present study by Smith et al. 1 , who noted the implant exposure in 3 cases, out of which 2 occurred in cases with etiology of severe trauma.Third, separation of the scleral flaps from the optic nerve is a further disadvantage because nerve will retract posteriorly, and thereby, the central retinal artery cannot aid in fibrovascular growth in the implant. Moreover, an open scleral cavity posteriorly can cause implant migration out of the central space. We also believe that though the separation of scleral flaps from the optic nerve reduces the tension on sclera anteriorly, it could possibly exert more tension on the conjunctiva and Tenon's fascia. This is because the optic nerve in addition to the recti would prevent the anterior movement of the implant and sclera.In the scleral quadrisection technique described by Yang et al. 2 and Sales-Sanz and Sanz-Lopez, 3 the implant is covered anteriorly by 2 layers of sclera. Thus, chances of exposure are minimized. The evisceration by the 2 scleral flaps technique does not provide this advantage.The evisceration technique should be performed so as to minimally disturb the orbita...

Unilateral Pleomorphic Lipoma of the Eyebrow

“…The commonest primary tumours are a variety of benign and malignant adnexa-derived epithelial tumours, of which the commonest is benign pilomatrixoma [1] that primarily affects the paediatric age group and presents as a chalky white nodule. A variety of eyebrow soft tissue lesions have been documented in case reports/series; they include fibrous histiocytoma [3], osteoma cutis [4], cellular neurothekeoma [5], dermatofibrosarcoma protuberans [6], rhabdomyoma [7], neurofibroma [8], nodular fasciitis [9] and conventional lipoma [10]. …”

“…The commonest benign tumour of the eyebrow skin is pilomatrixoma [1] in the paediatric age group, followed by dermoid cysts [2]. Soft tissue lesions are even rarer, and case reports/few series for the following lesions have been documented: fibrous histiocytoma [3], osteoma cutis [4], cellular neurothekeoma [5], dermatofibrosarcoma protuberans [6], rhabdomyoma [7], neurofibroma [8], nodular fasciitis [9] and conventional lipoma [10]. We report the clinical and histopathological features of an eyebrow soft tissue mass in a 65-year-old female, discuss the clinical and histopathological differential diagnoses and survey the literature of eyebrow tumours affecting the subcutis.…”

André Nanta (1883-1963) and the nevus which bears his name

“…It is postulated that secondary ossification is the consequence of folliculitis, trauma, or neoplastic proliferation, which may induce the dermal fibroblasts to differentiate into osteoblasts [1]. Histologically, the osteomas are composed of well-formed bony spicules with prominent cement lines and calcification.…”

“…A nevus of Nanta lesion is characterized by the presence of cutaneous ossification (osteoma cutis) of an existing melanocytic nevus [1][2][3][4]. It is postulated that secondary ossification is the consequence of folliculitis, trauma, or neoplastic proliferation, which may induce the dermal fibroblasts to differentiate into osteoblasts [1].…”