Repair of Giant Anterior Skull Base Encephalocele Containing Intralesional Eloquent Brain: Technical Note

Pediatric Congenital Anterior Skull Base Encephaloceles and Surgical Management: A Comparative Review of 22 Patients Treated Transnasally, Transcranially, or Combined Approach With a Review of the Literature

BACKGROUND AND OBJECTIVES

Anterior basal encephaloceles are considered a rare entity and are often associated with midline cerebral abnormalities. Those with a large skull base defect and herniation of brain parenchyma in the neonate or young infant present unique challenges for surgical management.

METHODS

We analyzed the neurosurgical administrative and operative databases between 1986 and 2022 to determine clinical presentation, operative approach, and outcome of basal encephaloceles.

RESULTS

Over the 36-year period, 27 pediatric anterior basal encephaloceles were managed, of which 22 had full documentation and images allowing comprehensive review. Mean age at presentation was 5 years (SD 4.94). The majority were transethmoidal encephaloceles (59%), followed by the transsphenoidal-sphenoethmoidal type (32%). Overall, 91% were managed surgically by a transcranial, endoscopic, or combined approach. Four children required subsequent procedures, predominantly for persistent cerebrospinal fluid leak. No significant differences in proportion of patients requiring interval/revision surgery after initial conservative, endoscopic endonasal, or transcranial surgery was identified. Neither age at surgery nor size of the defect on computed tomography scan was associated with the need for revision surgery. Size of cranial defect was significantly smaller in the endoscopic group ( P = .01). There was a historic tendency for younger children with larger defects to have a transcranial approach. With the addition of endoscopic skull base expertise, smaller defects in older children were more recently treated endoscopically.

CONCLUSION

Basal encephaloceles are rare and complex lesions and are optimally managed within a skull base multidisciplinary team able to provide multiple approaches. Large skull base defects with brain parenchymal involvement often require a transcranial or combined transcranial-endoscopic approach.

Persisting embryonal infundibular recess (PEIR) and transsphenoidal-transsellar encephaloceles: distinct entities or constituents of one continuum?

Persisting embryonal infundibular recess (PEIR) is a very rare anomaly of the floor of the third ventricle in which the embryonic morphology of the infundibular recess (IR) persists. The exact underlying mechanism of development of PEIR is unknown, and the anomaly has been reported as an isolated finding or in association with other conditions. On the other hand, trans-sphenoidal encephaloceles are the rarest form of basal encephaloceles. The trans-sphenoidal trans-sellar encephalocele (TSE) is the least common variant in which the pituitary gland, pituitary stalk, optic pathways, parts of the third ventricle and IR may be present within the encephalocele. We recently treated one patient with TSE. Based on the observed morphological similarity of the IR in our patient and in the published cases of PEIR, we reviewed the literature in order to validate the hypothesis that PEIR and TSE may possibly belong to one spectrum of malformations. Across the published reports, the morphology of the IR in TSE is very closely similar to PEIR. Moreover, radiological, patho-anatomical, and embryological evidence is in support to our hypothesis that PEIR and TSE are most likely the two extremes of the same continuum of malformations.

An uncommon etiological factor for aspiration pneumonitis caused by spontaneous sphenoid sinus meningoencephalocele with cerebrospinal fluid rhinorrhea: a case report

BACKGROUND

Aspiration pneumonitis is an inflammatory disease of the lungs which is difficult to diagnose accurately. Large-volume aspiration of oropharyngeal or gastric contents is essential for the development of aspiration pneumonitis. The role of cerebrospinal fluid (CSF) rhinorrhea is often underestimated as a rare etiological factor for aspiration in the diagnosis process of aspiration pneumonitis.

CASE PRESENTATION

We present a case of a patient with 4 weeks of right-sided watery rhinorrhea accompanied by intermittent postnasal drip and dry cough as the main symptoms. Combined with clinical symptoms, imaging examination of the sinuses, and laboratory examination of nasal secretions, she was initially diagnosed as spontaneous sphenoid sinus meningoencephalocele with CSF rhinorrhea, and intraoperative endoscopic findings and postoperative pathology also confirmed this diagnosis. Her chest computed tomography showed multiple flocculent ground glass density shadows in both lungs on admission. The patient underwent endoscopic resection of meningoencephalocele and repair of skull base defect after she was ruled out of viral pneumonitis. Symptoms of rhinorrhea and dry cough disappeared, and pneumonitis was improved 1 week after surgery and cured 2 months after surgery. Persistent CSF rhinorrhea caused by spontaneous sphenoid sinus meningoencephalocele was eventually found to be a major etiology for aspiration pneumonitis although the absence of typical symptoms and well-defined risk factors for aspiration, such as dysphagia, impaired cough reflex and reflux diseases.

CONCLUSIONS

We report a rare case of aspiration pneumonitis caused by spontaneous sphenoid sinus meningoencephalocele with CSF rhinorrhea, which can bring more attention and understanding to the uncommon etiology for aspiration, so as to make more accurate diagnosis of the disease and early surgical treatment.