Encephalocele presenting as lower lid swelling: A rare case report.

Encephalocele is a rare congenital abnormality characterized by abnormal protrusion of brain and meninges through an opening in the skull. We report an 8-year-old girl who presented with a swelling in the right lower lid for the last 6 years. In her infancy, she had undergone surgery for a very small swelling located in the right nasolacrimal area. On further clinicoradiological evaluation, anterior encephalocele was diagnosed. This case highlights the uncommon site of anterior encephalocele; misdiagnosis and mismanagement of which could result in dreaded complications such as meningitis and cerebrospinal fluid leaking fistula formation.

Encephalocele is the herniation of the cerebral tissue, meninges, and cerebrospinal fluid (CSF) through the bony defect in the skull. In anterior encephalocele, herniation of meninges occurs through the skull in different directions and locations at the site of meeting of the nasal, maxillary, and lacrimal bones. This diversity together with the extent of herniation explains the variety of clinical appearance.[1] It is a congenital condition which represents the defective closure of the neural tube, probably caused by an early teratogenic insult and exhibits a different geographical distribution.[2] Encephalocele usually causes sign and symptoms which are misleading.[3] Herein, we report a patient who presented with the right eye lower lid swelling which on further neuroradiological evaluation turned out to be a case of encephalocele. A written and informed consent was taken from the patient for reporting this case.

Case Report

An 8-year-old girl approached us with the complaint of a painless swelling in the right lower lid and watering for the last 6 years [Fig. 1a]. The swelling was gradually increasing in size. There was no history of trauma. At the age of 1 year, the patient had been operated on for a peanut-sized swelling over the medial side of the right eye. This was performed under the clinical impression that the swelling might be dacryocystocele or dermoid. Operative notes of the previous surgery mentioned that the clear fluid came out of the swelling. The histopathology of the excised lesion demonstrated the presence of fibrous tissue only. The patient remained asymptomatic for 2 years after which the swelling reappeared below the scar of the previous surgery. Since then, the swelling has been gradually increasing in size. On examination, there was a cystic swelling present below the medial canthus, extending down to the right lower lid. The swelling was nonpulsatile, irreducible, and did not increase on cough and straining. A bony defect could be felt under the swelling. There were no stigmata of neurofibromatosis and rest of the ophthalmic and systemic examination was normal. Nasolacrimal system was found patent on irrigation of fluid. Computed tomography head and orbit disclosed a bony defect in the anteromedial part of the right orbit [Fig. 1b]. Magnetic resonance imaging demonstrated T2 hyperintense lesion in the inferomedial aspect of the right orbit suggestive of encephalocele. The patient underwent frontal craniotomy and basal repair by a pedicle pericranial flap to prevent the CSF egress into the encephalocele. After surgery, the lower lid swelling disappeared with the resolution of associated clinical symptoms [Fig. 1c].

Figure 1

Case description of anterior encephalocele. (a) Clinical picture showing the right eye lower lid swelling. (b) Computed tomography head and orbit (coronal view) showing anterior fossa skull base defect along the cribriform plate on the right side along with herniation of intracranial soft tissue into the ethmoid air sinuses and medial aspect of the right orbit through a medial orbital wall defect (black arrow). (c) Postoperative photo showing the resolution of lower lid swelling

Discussion

Our case in infancy had a small swelling on the medial side of the right eye which was not increasing on crying, irreducible and nonpulsatile and was misdiagnosed as dacryocystocele by the treating ophthalmologist. The absence of associated features such as broad nasal root, hypertelorism, and optic disc abnormalities made the diagnosis further difficult. The patient came to us when she was 8 years and had anterior encephalocele at an unusual location – lower lid. The scar of previous surgery made the encephalocele to descend down into the lower lid where ample space was available for the cyst to enlarge slowly. The clinical signs which are usually present in an encephalocele are pulsation, reducibility, and increase in the swelling size on coughing and straining, which were absent in this case. This is due to narrow neck or closure of the neck of encephalocele by herniated brain tissue.[4] Anterior encephaloceles have been reported with good treatment outcome in earlier large series from India.[567] A good surgical outcome has also been reported in an 11-day-old infant diagnosed with anterior orbital meningoencephalocele by Bersaniand Cecchi.[8]

Conclusion

This case exemplifies the error in diagnosing an anterior encephalocele when located at an unusual location, nasolacrimal area. A radiological imaging at the time of initial presentation in infancy could have avoided second surgery. The patient underwent surgery without imaging which might have resulted in grave complications such as meningitis. Therefore, a high clinical suspicion and proper clinical examination and imaging modality are required to avoid further devastating complication when dealing with such cases.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

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Conflicts of interest

There are no conflicts of interest.