Glial heterotopia of the face.

The authors report a case of combined subcutaneous and intranasal glial heterotopia of the face in a 4-month-old boy. The pathogenesis and differential diagnoses of this rare developmental disorder are discussed as is the importance of careful radiologic findings for appropriate surgical decision.

[Nasal glial heterotopia: embryological and clinical approaches]. / Hétérotopie gliale nasale: approches clinique et embryologique.

INTRODUCTION: Nasal gliomas or heterotopia are nonhereditary congenital malformations composed of heterotopic neuroglial tissue. They usually present in infancy. Evaluation should include preoperative imaging with CT scan and/or MRI to rule out intracranial extension. There have been several cases reported in which nasal gliomas were misdiagnosed as capillary hemangiomas. The differential diagnosis includes prenasal space developmental impairment, which are nasoethmoidal meningoencephaloceles, nasal dermoid and epidermoid cysts. CASE REPORT: We describe the case of a newborn male infant presenting at birth with a paramedial nasal glioma. An embryological and clinical analysis of nasal gliomas is proposed. DISCUSSION: Nasal glioma is an uncommon congenital lesion presenting as a large panel of midline craniofacial anomalies. The embryological and anatomical origins of nasal gliomas are reviewed. The most known embryological theory was described by Grünwald in 1910 and is called the "prenasal space" theory. This theory is very attractive because of the embryopathogenic continuum proposed among dermoids, gliomas, and encephaloceles. In this article, we discuss major embryological theories on nasal gliomas pathogenesis and propose that while the prenasal space theory can explain the occurrence and the continuum between basal anterior or prenasal encephaloceles and gliomas, it cannot explain the occurrence of craniofacial demoids of the same topography. Better knowledge of embryological mechanisms implicated in the pathogenesis of nasal gliomas can help clinical management of this kind of malformations.

[Management of nasal fistulas with intracranial extension]. / Management medianer Nasenfisteln mit intrakranieller Ausbreitung.

BACKGROUND: Medial nasal fistulas are rare congenital malformations that mostly become obvious by recurrent infections such as secretion from the fistula opening or swelling of the nasal tissues. In rare cases, these fistulas may extend intracranially with meningeal irritations. PATIENT PRESENTATION: Three patients with medial nasal fistulas were operated during the last two years in our department. In two children, the fistulas ended at the glabella. In one older boy, the fistula revealed an intracranial extension. In the last case, a combined rhino- and neurosurgical approach was applied to perform a complete resection of the fistula. DISCUSSION: During the second embryonic month of facial development, the medial nasal processes approach each other with a fusion of their epithelial covering that completely disappears during later stages. If parts of this epithelial fusion zone persist, epithelial remnants may develop into nasal fistulas or dermoids. The adequate therapy of these nasal malformations consists of a complete surgical removal.

[Clinical and embryological approaches to nasal dermoid sinus cysts]. / Kystes et fistules du dos du nez: de l'embryologie à la clinique.

Nasal dermoid sinus cyst (NDSC) is an uncommon congenital lesion presenting as a large panel of midline craniofacial anomalies. Thirty children with nasal midline masses and/or sinus ostia were surgically treated in the pediatric ENT and cervicofacial surgery department of Trousseau's children's hospital (Paris-France) between 1995 and 2002. All our patients underwent radiological evaluation including CT scan (including axial and coronal planes) and/or MRI (in all three planes) in search of intracranial extension. Thirteen of our patients presented with a midline cyst only, ten had nasal pit only, and seven had combined anomalies. Preoperative radiology and surgery showed an intracranial extension in 3 patients, which exhibited contact of the cyst with the dura. Recurrence being expected if any dermal tissues were left in place, "one-time-excision management" was the rule. CT and MR imaging features were reviewed. The external rhinoplasty procedure resulted in a wide surgical approach, low recurrence and good esthetic results. The embryological and anatomical origins of NDSCs are reviewed. Development of NDSC during embryological development implicates two necessary and sufficient conditions: competence of the ectodermal and mesectodermal cells to form dermoid tissue with epithelial-mesenchymal interactions, and a topographical site of ectodermal inclusion, which fits well with the various clinical presentations of NDSCs. We propose to distinguish NDSCs of anterior topography, located at the anterior skull base level from the basal NDSCs, located at the middle skull base level. We reviewed the various localizations of NDSCs, revisiting a forgotten embryological theory, which unify the various clinical localizations of anterior NDSCs.

[2 modalities in the embryogenic process of frontonasal cysts and fistulae]. / Deux modalités dans le processus embryogénique des kystes et fistules fronto-nasaux.

The two principal embryogenic theories, persistence of residual structures remaining after closure of the anterior neuropore and inclusion of epiblastic derivatives in the prenasal space, may be combined, with resulting two embryonic varieties of these malformations. Glabellar cysts, with or without fistulae extending them downwards, and which remaining at superficial level may perforate the true nasal bones. Other fistulae can develop which extend deeply and present variable dilatations with a more or less oblique path upwards depending on the level of their opening into the nose.

Nasolabial cyst. Case report.

We present a case of nasolabial cyst. The clinical and histological aspects are discussed and a new concept of the embryology of the nasolabial cyst in described.