Delayed diagnosis and surgical repair of a chronic post-traumatic cerebrospinal fluid fistula with encephalocele in a child

Abstract

Background:

Encephalocele is a pathological condition characterized by the herniation of intracranial contents through a cranial bone defect. Although most cases are congenital, traumatic encephaloceles can occur following blunt head injury, surgical interventions, or other acquired causes. These lesions are clinically significant due to their association with cerebrospinal fluid (CSF) leakage and the risk of life-threatening meningitis. Traumatic encephaloceles in children are exceedingly rare, particularly those involving the fronto-ethmoidal region.

Case Description:

We report the case of a 13-year-old girl with delayed-onset CSF rhinorrhea, beginning 4 years after craniofacial trauma. Imaging revealed right frontal and fronto-basal parasagittal cortico-subcortical encephalomalacia, an extensive defect at the ethmoid roof, and an associated ethmoidal encephalocele. The patient underwent single-stage endonasal endoscopic repair with multilayer skull base reconstruction. Postoperative follow-up demonstrated complete resolution of rhinorrhea and no recurrence on imaging.

Conclusion:

This case highlights the importance of long-term vigilance in pediatric patients with craniofacial trauma and supports the use of endonasal endoscopic techniques as an effective and minimally invasive approach for the repair of chronic CSF fistulas and associated encephaloceles.

INTRODUCTION

Encephalocele is a pathological condition characterized by the herniation of intracranial contents through a defect in the cranial bones.[4] While most cases are congenital, occurring in approximately 1 in 5,000 live births, encephaloceles can also result from acquired causes. Among these, traumatic encephaloceles are the most common, typically arising from skull fractures, surgical interventions, or severe head injuries.[6] Other less frequent etiologies include tumor-related erosion or spontaneous development.

Traumatic fronto-ethmoidal encephaloceles, although rare, are particularly associated with blunt craniofacial trauma or iatrogenic factors.[9,10] These lesions pose significant clinical risks, primarily due to cerebrospinal fluid (CSF) leakage and the consequent potential for life-threatening complications such as meningitis.[8] Prompt diagnosis and surgical repair of the encephalocele and any associated CSF fistula are essential to reduce morbidity and prevent infection.[10]

Due to the scarcity of cases, precise prevalence rates for traumatic encephaloceles in children are not well established. Their occurrence is considered exceedingly rare, and most available information comes from individual case reports rather than large-scale studies.[6,10,12]

CASE PRESENTATION

A 13-year-old female presented with persistent CSF rhinorrhea, which had been ongoing for 4 years following frontal cranioencephalic trauma. The injury was sustained at the age of nine when a wall collapsed on her during an accident in a less developed country. Initial medical evaluation did not identify the full extent of the injury, as the ethmoidal fracture was missed on the initial imaging evaluation, and no definitive diagnosis or treatment was established at that time.

Over the ensuing years, the patient experienced intermittent clear nasal discharge, particularly evident upon waking with her pillow soaked, but without fever or other signs of acute infection such as meningitis or encephalitis. Due to the chronic nature of her symptoms and the lack of resolution, her parents eventually sought medical care in a developed country.

On clinical evaluation, the so-called reservoir sign[7] was identified: After a period without visible discharge, a significant volume of clear fluid appeared when she tilted her head forward, strongly suggestive of CSF rhinorrhea. There were no signs of meningitis or other alarming neurological symptoms.

Brain computed tomography (CT) revealed right frontal and fronto-basal parasagittal cortico-subcortical encephalomalacia, along with an extensive defect at the ethmoid roof and suspected naso-ethmoidal encephalocele [Figure 1]. For further clarification, magnetic resonance imaging (MRI) confirmed the presence of an ethmoidal encephalocele involving the right fronto-orbital gyrus, with evidence of inflammatory changes in the adjacent posterior ethmoid cell [Figure 2].

Figure 1:

Non-contrast brain computed tomography demonstrating an anterior skull base defect involving the ethmoid roof with suspected encephalocele (red arrow). (a) Coronal soft-tissue and bone window. (b) Sagittal bone window. (c) Axial bone window.

Figure 2:

Brain magnetic resonance imaging demonstrating an ethmoidal encephalocele with herniation into the ethmoid sinus and associated local inflammatory changes (red arrows). (a) Coronal T2-weighted image. (b) Sagittal T2-weighted image. (c) Sagittal non-contrast T1-weighted image demonstrating anterior skull base herniation into the ethmoid sinus.

Given the chronicity of the CSF fistula (4 years) and the associated encephalocele, the patient was scheduled for elective endonasal endoscopic surgery in collaboration with the otorhinolaryngology (ear, nose, and throat [ENT]) team.

Surgical procedure

Under general anesthesia, an endonasal endoscopic approach was performed. Intraoperatively, an encephalocele was identified in the right olfactory fossa with a persistent CSF fistula [Figure 3]. A maxillary uncinectomy was performed to identify and widen the maxillary sinus ostium, followed by anterior and posterior ethmoidectomy and medial and superior turbinectomy. The sphenoid sinus ostium was identified and enlarged to improve access and visualization.

Figure 3:

Intraoperative endoscopic view demonstrating the encephalocele at the olfactory fossa (black arrow).

The encephalocele was mechanically retracted by applying gentle pressure using a cottonoid [Figure 4], revealing a skull base defect at the cribriform plate measuring approximately 1.5 × 1.5 cm. Progressive coagulation successfully reduced the encephalocele into the intracranial compartment.

Figure 4:

Endoscopic intraoperative view showing mechanical reduction of the encephalocele (black arrow).

A multilayer reconstruction was then undertaken. Closure was initiated with placement of a dural substitute over the defect [Figure 5], followed by Surgicel, bone fragments harvested from the middle turbinate, and a porous polyethylene implant (MEDPOR®, Stryker, Kalamazoo, MI, USA) to reinforce the skull base [Figure 6]. Finally, a vascularized nasoseptal flap was rotated into position and secured over the reconstruction, supported by fibrin glue [Figure 7]. Resorbable and non-resorbable nasal packing materials were applied to ensure stability of the repair. The procedure was completed without intraoperative complications.

Figure 5:

Intraoperative view following dural closure (black arrow).

Figure 6:

Placement of the MEDPOR^® implant (Stryker, Kalamazoo, MI, USA) during anterior skull base reconstruction (black arrow).

Figure 7:

Reconstruction using a vascularized nasoseptal flap (black arrow).

Postoperative course and follow-up

Postoperatively, the patient was monitored closely for recurrence of CSF leakage and signs of infection. She received prophylactic antibiotics (ceftriaxone 1000 mg twice daily) for 7 days.

A follow-up CT scan [Figure 8] was performed 4 days after surgery, revealing no intracranial lesions. The scan demonstrated a moderately hyperdense linear structure corresponding to the reconstruction of the anterior cranial fossa floor.

Figure 8:

Postoperative head computed tomography demonstrating integrity of the anterior skull base reconstruction (red arrow). (a) Coronal view bone window. (b) Coronal view soft-tissue window. (c) Sagittal view soft-tissue window.

The patient was discharged 1 week after surgery without complications. At a follow-up visit in the otorhinolaryngology outpatient clinic 4 months later, nasal endoscopy confirmed good healing with a viable graft and no signs or symptoms of nasal CSF fistula [Figure 9].

Figure 9:

Endoscopic evaluation at 4-month follow-up demonstrating satisfactory healing and reconstruction integrity (red circle).

In addition, follow-up MRI [Figure 10] demonstrated a successful surgical repair with no evidence of recurrent herniation or new intracranial lesions. The patient remained asymptomatic, with no further episodes of rhinorrhea or infectious complications.

Figure 10:

Follow-up T2-weighted brain magnetic resonance imaging demonstrating stable repair with no evidence of residual encephalocele (red arrows). (a) Coronal view. (b) Sagittal view. (c) Axial view.

DISCUSSION

Traumatic fronto-ethmoidal encephaloceles represent an uncommon but clinically significant consequence of anterior skull base injury. The thin bony walls of the ethmoid sinus are particularly susceptible to disruption following craniofacial trauma, making this region a common site for post-traumatic skull base defects and encephaloceles.[6,10] Herniation of meninges and intracranial contents into the paranasal sinuses may subsequently occur and is frequently associated with CSF leakage. In most reported cases, CSF rhinorrhea develops within hours to months after the traumatic event, while bacterial meningitis, often recurrent, typically occurs within the 1^st 3 months if the fistula remains untreated.[8]

The present case demonstrated an unusual clinical course. Although the patient sustained significant craniofacial trauma during childhood, rhinorrhea became clinically evident only approximately 1 year later, and no episodes of meningitis occurred despite 4 years of intermittent CSF leakage. This delayed, and relatively indolent presentation likely contributed to the prolonged interval before definitive diagnosis and treatment. Furthermore, the absence of early infectious complications may have reduced clinical suspicion for an anterior skull base defect. The initial imaging evaluation performed after trauma was reportedly interpreted as negative; however, based on subsequent findings, it is likely that the ethmoidal fracture was not recognized at that time. This highlights the diagnostic challenges associated with subtle anterior skull base injuries, particularly in the acute trauma setting and in pediatric patients.

Imaging plays a central role in the diagnosis of traumatic CSF fistulas and encephaloceles. High-resolution thin-slice CT remains particularly valuable for identifying osseous skull base defects, whereas MRI and magnetic resonance cisternography provide superior characterization of herniated intracranial contents and associated soft tissue abnormalities.[8] CT cisternography may also be useful in selected cases when the site of leakage remains uncertain. In the present patient, a combined CT and MRI evaluation was sufficient to demonstrate both the ethmoidal defect and the associated encephalocele, allowing accurate surgical planning without the need for invasive diagnostic studies.

Traumatic encephaloceles in children remain exceedingly rare, and the current literature is limited predominantly to isolated case reports and small case series. Earlier reports suggested that only approximately 25 cases of post-traumatic encephaloceles had been documented by 2010. More recently, a 2023 systematic review identified 52 reported cases across all age groups, with ages ranging from 6 months to 66 years and a mean age of 25.3 years.[6] The orbital roof, ethmoid bone, and sphenoid bone were the most commonly affected structures, while presenting symptoms varied according to lesion location and included CSF rhinorrhea, exophthalmos, visual symptoms, and hearing loss.[6] The scarcity of pediatric cases limits the establishment of standardized diagnostic and therapeutic strategies, reinforcing the importance of continued case reporting and detailed characterization of these lesions.

A comparable case described by Oswal et al. [9] involved a 16-year-old male with traumatic frontoethmoidal encephalocele following a bicycle accident, successfully treated with a single-stage multidisciplinary procedure involving neurosurgery and maxillofacial surgery teams.[9] Similar reports emphasize the importance of multidisciplinary collaboration and individualized surgical planning in the management of complex anterior skull base defects.

Surgical repair remains the cornerstone of treatment for traumatic encephaloceles associated with CSF leakage, particularly in chronic cases or when the risk of intracranial infection is significant.[8,10] Historically, management often involved transcranial or combined intracranial–extracranial approaches, frequently requiring staged procedures with craniotomy and subsequent craniofacial reconstruction.[10] Although effective, these techniques may be associated with greater morbidity and longer recovery periods.

In recent years, endonasal endoscopic techniques have become increasingly favored because they provide excellent visualization of the anterior skull base while minimizing surgical morbidity, hospital stay, and cosmetic sequelae.[10,12] The refinement of these reconstructive techniques largely originated from the development of expanded endoscopic approaches for pituitary adenomas and other skull base lesions, where multilayer watertight dural closure and vascularized nasoseptal flap reconstruction significantly reduced postoperative CSF leak rates.[1-3,5,11] Reported success rates for closure of CSF fistulas using endoscopic approaches are high, particularly in well-selected cases. In the present patient, the anatomical location of the defect and the chronic nature of the fistula favored a single-stage endoscopic endonasal repair performed collaboratively with the ENT team. The favorable postoperative course and absence of recurrence support the role of minimally invasive endoscopic reconstruction as a safe and effective therapeutic option in selected pediatric patients with traumatic anterior skull base defects.

CONCLUSION

This case highlights the critical need for heightened clinical vigilance in patients with a history of craniofacial trauma, particularly when persistent or intermittent clear nasal discharge occurs, even years after the initial injury. The patient underwent successful endonasal endoscopic repair of an ethmoidal encephalocele associated with a chronic CSF fistula, with uneventful postoperative recovery and no evidence of recurrence on follow-up.

The findings also emphasize the value of appropriate radiological evaluation in suspected CSF leaks and the role of surgical treatment in preventing complications such as meningitis. Given the rarity of post-traumatic encephaloceles and chronic CSF fistulas in pediatric patients, continued case reporting may contribute to improved recognition and management of these conditions.

Ethical approval:

Institutional Review Board approval is not required.

Declaration of patient consent:

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given consent for their images and other clinical information to be reported in the journal. The patient understands that the patient’s 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:

Nil.

Conflicts of interest:

There are no conflicts of interest.

Use of artificial intelligence (AI)-assisted technology for manuscript preparation:

The authors confirm that there was use of artificial intelligence (AI)-assisted technology. The authors used ChatGPT (OpenAI) exclusively for assistance with English language editing and manuscript phrasing. No AI tool was used for data analysis, interpretation, or the generation of scientific conclusions.

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