Congenital transsphenoidal meningocele: case report and review of the literature

Meningocele in the Parapharyngeal Space: A Case Report and Review of the Literature

The parapharyngeal space has been described as an inverted pyramid shape with the base of the skull and the great cornu of the hyoid bone at the top. Tumors of the parapharyngeal space account for 0.5% of head and neck tumors and a wide range of tumor types can occur in this area, 80% of which are benign, the most common being pleomorphic adenomas of the salivary glands and neurogenic tumors. We present a 39-year-old woman who was hospitalized due to left-sided neck pain with a feeling of blockage in the left ear and hearing loss for 10 months. Imaging showed that the mass was not connected to the cranium and the patient underwent surgical resection via a transoral approach, where the contents of the mass were found to be cerebrospinal fluid, and meningocele in the parapharyngeal space is a rare occurrence. The patient presented mainly with painful symptoms, which were eventually relieved by nerve block therapy.

Small spheno-ethmoidal meningoencephalocele versus ethmoidal mucocele in spontaneous intracranial hypotension

Background

Meningoencephalocele is defined as an abnormal sac of brain tissue and meninges extending beyond natural skull margins, often leading to cerebrospinal fluid (CSF) leakage. When this condition arises in the spheno-ethmoidal region, the diagnosis becomes more challenging as it can be mistaken for other nasal pathologies, such as mucocele.

Research question

We show in this case report a non-congenital sphenoethmoidal meningoencephalocele causing rhinoliquoral fistula and spontaneous intracranial hypotension.

Results

this 65-year-old woman presented with sporadic rhinoliquorrhoea associated with orthostatic headache, nausea and dizziness. Brain MRI revealed a small lesion of an ethmoidal sinus, which was successfully treated with endoscopic endonasal surgery. Histology confirmed the presence of meningoencephalic tissue positive for S100 protein on immunohistochemistry.

Conclusions

When dealing with lesions of the paranasal sinuses in contact with the anterior skull base, rhinoliquorrhoea presence suggests meningoencephalocele. In dubious cases, a proper workup, including a thorough clinical history and neurological examination, specific imaging, and a direct search of CSF-like markers, is essential to support the differential diagnosis. In such cases, a transnasal endoscopic surgical approach is recommended to obtain a final histological diagnosis and to perform eventual dural plastic surgery.

Sternberg’s canal: a rare site of CSF leak—our experience and management of a series of cases at a tertiary care hospital in South India

Background

The lateral craniopharyngeal canal or Sternberg’s canal is located in the postero-lateral part of the sphenoid sinus. It is the weakest area of the skull base, originating due to defective fusion during embryological development in a small proportion of individuals. Hence, it can give rise to CSF leaks from that region. Due to the proximity of this region to the internal carotid artery, optic nerve, and cavernous sinus, it proves to be challenging to repair these defects. The exact location, role in the causation of CSF leaks, and clinical presentation with arachnoid herniation are also subject to much controversy.

Results

In our case series, we describe 7 patients with the rare clinical entity of CSF leak from the Sternberg’s canal, who had a mean age of 38.4 years, 4 of whom also had an arachnoid herniation through the canal. One patient already underwent prior endoscopic surgery for the CSF leak. We highlight a trans-nasal trans-sphenoid approach with multi-layer closure, i.e., fat plug, fascia, and a naso-septal flap with the use of an additional layer of muscle in one of the cases, following which all had good outcomes. Since the primary concern with this rare clinical scenario is correct identification and adequate exposure of the leak for repair, we additionally undertook a trans-pterygoid approach in 2 of our patients.

Conclusions

The key to the successful repair of the Sternberg’s canal leak lies in its accurate identification and exposure. In our series, we achieved good exposure by drilling the pterygoids and lateral sphenoid walls along with the use of angled endoscopes for visualization. Our case series highlights the linear relation of elevated BMI with spontaneous CSF leaks in the absence of benign intracranial hypertension and the reinforcement of repair with the use of a harvested naso-septal flap. Our multi-layered closure ensured good results and no recurrence of a leak in any of our patients.

[Endoscopic endonasal reconstruction of skull base defects in the lateral recess of the sphenoid sinus: evaluation of computed tomograms for planning operations]

OBJECTIVE

Determine the influence of the anatomical features and sizes of the lateral pocket with a defect on the choice of surgical access and the quality of the performed plastics.

MATERIAL AND METHODS

A retrospective analysis of computed tomograms of 38 patients who underwent surgical treatment at the Burdenko National Medical Research Center for Neurosurgery of the Ministry of Health of Russia about defects of the skull base in the area of the lateral pocket of the sphenoid sinus. The patients were divided into three groups depending on the approach used (the 1st group), the recurrence rate (the 2nd group), and the characteristics of intraoperative visualization of the defect (the 3rd group).

RESULTS

There were no statistically significant differences in anatomical features in patients who underwent trans-pterygoid and transsphenoidal approaches, as well as in patients of the 2nd group. Patients of the 3rd group (with visualization features) showed statistically significant differences between the distance from the defect to the VR line (p=0.007). In patients with good visualization of the defect using direct optics, this distance was shorter than in patients in whom the defect was visualized with an angled endoscope. No other anatomical differences were noted.

CONCLUSIONS

The anatomical features of the lateral pocket structure (type of pneumatization, size and volume) did not affect the choice of access to the defect and the frequency of recurrence. When comparing the approaches, it was noted that the trans-pterygoid access, providing direct visualization of defects, minimizes the risk of recurrence in the postoperative period. An objective anatomical indicator for choosing an access to the defects of the lateral pocket can be the distance from the defect to the VR line: at a distance of more than 0.7 cm, it is advisable to perform a trans-pterygoid approach; at a distance of less than 0.7 cm, it is possible to achieve direct visualization of the defect and perform high-quality plastic surgery with a transsphenoidal access.

Transnasal endoscopic surgery of sphenoid meningocele associated with pituitary adenoma. A case report

BACKGROUND

Transsphenoid meningoencephalocele is a congenital anomaly formed by herniation of an ependyma delimited sac through a bony defect into the sphenoid sinus. The sac contains cerebrospinal fluid and neurovascular structures. The prevalence of transsphenoid meningoencephalocele in the adult population is rare. It usually manifests as nasal liquorrhoea.

METHODS AND RESULTS

This case report presents an adult male who underwent surgery due to suspected pituitary macroadenoma. The surgery was performed endoscopically via the transnasal approach with a surprising finding of true transsphenoid meningoencephalocele. Ectopic solid tissue was found in the sphenoid sinus in which pituitary adenoma was histologically confirmed.

CONCLUSION

This paper presents a previously unpublished combination of true transsphenoid meningoencephalocele and pituitary adenoma in an adult individual.

Endoscope-assisted microsurgical repair in trigeminal meningocele: case report

Trigeminal meningocele is a rare disease that results in rhinorrhea. Treatments with endoscopic approaches and open craniotomies have high recurrence rates, and controversy regarding the most effective surgical strategy for trigeminal meningocele is ongoing. The authors report a case of a 13-year-old female patient with a diagnosis of trigeminal meningocele determined after she presented with a history of intermittent headaches, suspected rhinorrhea, and recurrent meningitis. In addition to the conventional method of covering the efflux point of CSF and filling the inside of the meningocele with fascial tissues, the authors selectively closed the influx point of CSF from the prepontine cistern to the meningocele using an anterior transpetrosal approach. On the basis of the preoperative images, the authors hypothesized that the influx point of CSF could not be observed under the microscopic direct view and instead used a flexible endoscope. A check valve-like structure with one-way communication of CSF from the prepontine cistern into the cystic cavity was identified and was closed. At the time of this report, 36 months postoperatively, the patient had no indications of recurrence. Although cases of trigeminal meningoceles are infrequently encountered and require a tailored approach, the results in this case thus far indicate that the use of an endoscope and open craniotomy is an effective strategy for surgical treatment.

Sphenoethmoidal meningoencephalocele with variable hypopituitarism: A case report and review of literature

Sphenoethmoidal meningoencephalocele is a rare congenital meningocele with unclear clinical course. Its clinical symptoms are diverse, and this disease is widely observed across all ages. The prognosis of this disease depends on the severity of the central nervous system complications. We reported a case of sphenoethmoidal meningoencephalocele incidentally discovered in a 2-yr-old patient, with the subsequent appearance of diabetes insipidus at school age. An endocrinological evaluation performed when the patient was nine years old using the TRH/CRH/LH-RH load test showed a low response of gonadotropins and slightly hyper-response and normal response of ACTH and TSH, respectively. GH provocative tests indicated severe GH deficiency. Desmopressin and GH treatment efficiently improved his growth rate and quality of life. His pituitary function had presumably been normal from the neonatal period to infancy, but the dysfunction gradually progressed over the next few years along with his physical growth. The symptoms were suspected to be the product of the natural course of his hypothalamus or pituitary gland degeneration, or were otherwise due to gradual damage by chronic mechanical compression or extension. These findings underscore the importance of conducting careful systemic management in the long term, specifically with respect to the endocrinological evaluation of sphenoethmoidal meningoencephalocele.

Endoscopic management of lateral sphenoid cerebrospinal fluid leaks: Identifying a radiographic parameter for surgical planning

OBJECTIVE

Repair of cerebrospinal fluid (CSF) leaks of the lateral recess of the sphenoid (LRS) sinus can be challenging to accomplish via an endoscopic transphenoidal approach. The endoscopic transpterygoid approach can improve surgical access to the lateral recess but requires more extensive surgical dissection. We review our experience with LRS CSF leak repair via both techniques to determine whether preoperative radiologic data can help predict the most appropriate surgical approach.

METHODS

Electronic medical records of patients with LRS CSF leaks were retrospectively reviewed at a single tertiary referral center. Radiographic measurements from preoperative computed tomography images were reviewed.

RESULTS

Twenty-two LRS CSF leaks were identified. The transphenoidal and transpterygoid approach were used in 6 (27.3%) and 16 (72.7%) cases, respectively.The mean vidian canal to foramen rotundum angle of the repairs accessed transphenoidally as compared to the transptyergoid approach were not significantly different (41.93° ±10.91, 40.72° ±19.49, respectively; P = .63). However, the mean volume of the LRS accessed by the transpterygoid approach was significantly greater compared to those accessed through the transphenoidal approach (0.97 cm3 ± 0.48, 0.39 cm3 ± 0.40, respectively; P = .04). A LRS volume of 0.400 cm3 or greater predicted the use of the transpterygoid approach with 93.3% sensitivity and 60.0% specificity.

CONCLUSION

This study demonstrated that LRS CSF leaks that necessitated repair by the transpterygoid approach, rather than transphenoidal approach, were in the context of significantly larger lateral recess. Assessment of the LRS volume is a quantifiable parameter to aid in preoperative surgical planning.

LEVEL OF EVIDENCE

Level 4.

A Rare Case of Sphenoid Encephalocoele Presenting with Fifth Cranial Nerve Involvement

A 14-year-old girl presented with chronic headache, recurrent episodes of vomiting, fever, and two episodes of generalized tonic clonic seizure in the past 2 months. Neuroimaging revealed herniation of the brain along with the dura through a defect in the left greater wing of the sphenoid. Left pterional craniotomy was carried out. Herniation of the dural sac along with its contents through the bony defect in the greater sphenoid wing was identified lateral to the V2 nerve passing through the foramen rotundum. The dural defect was repaired. Bony defect was covered with a circular titanium plate. The patient did not have cerebrospinal fluid rhinorrhea postoperatively. At 6-month follow-up, she was asymptomatic.

Endoscopic endonasal resection of congenital trans-sphenoidal meningoencephalocele with extension to the epipharynx in early childhood: a case report

Background

The clinical presentation of sphenoid sinus meningoencephaloceles (MEC) may have insidious onset and evolution. Contemporary treatment incorporates endoscopic resection via the endonasal route.

Case description

We present a case of 3 year old girl who had been complaining of permanent nasal discharge, impeded nasal breathing and difficulty with feeding since she was 5 months old. There was no history of rhinoliquorrhea. Pre-operative magnetic resonance imaging demonstrated MEC that extended from the sellar region through the non-pneumatized sphenoid sinus to the nasopharynx. The lesion was resected via endoscopic endonasal approach. Follow-up rhinoscopy confirmed the absence of post-operative cerebrospinal fluid leak.

Conclusion

Endoscopic endonasal approach can be an effective and a safe treatment option for resection of congenital transsphenoidal MEC in early childhood.

Neck swelling due to skull base (pseudo)meningocele protruding through a congenital skull base bone defect: a case report

BACKGROUND

Meningocele is defined as a protrusion of the meninges through an opening in the skull or spinal column, forming a bulge or sac filled with cerebrospinal fluid. A pseudomeningocele is defined as a cerebrospinal fluid (CSF) collection formed due to escape of CSF through a dural defect with trapping of CSF into the surrounding soft tissues. We herby report rare occurrence of a large (pseudo)meningocele in a young patient with congenital skull base defect presenting as upper lateral neck swelling.

CASE PRESENTATION

We present the case of a 17-year-old boy who had painless progressive swelling right side of the upper neck without any history of meningitis or CSF leak. He had a history of undergoing cranioplasty using steel plates for nontraumatic boggy swelling right parieto-occipital region at the age of 5 years at another hospital. Clinical examination showed painless swelling right side of the upper neck, with positive cough impulse and transillumination. CT head with cisternography showed a large right skull base defect through which a large pseudomeningocele was herniating, thus producing upper neck swelling and compressing oral cavity. The neck swelling and intraoral bulge reduced in size after the coperitoneal shunt.

CONCLUSION

Differential diagnosis of (pseudo)meningocele should be considered while evaluating a painless progressive upper neck swelling having cough impulse and transillumination in a young patient.

Transsphenoidal meningoencephalocele protruding into the nasal cavity

Spontaneous transsphenoidal meningoencephalcele is a rare entity, even rarer through the Sternberg’s canal, a congenital defect on the lateral wall of the sphenoid sinus. We report such a case in an obese 52-year-old female with spontaneous cerebrospinal fluid (CSF) rhinorrhoea and recurrent meningitis. Brain CT, MRI and CT cisternography were performed. Surgical correction and short-term follow-up were recorded. CT scan showed a defect on the lateral wall of the right sphenoid sinus filled with a soft tissue mass extending to the nasal cavity. MRI scan revealed brain parenchyma from the right temporal lobe herniated through the sphenoid bone defect. CT cisternography showed 270 mmH₂O opening pressure and confirmed the CSF leakage. Surgical correction was performed with resolution of the symptoms. MRI and CT are complementary modalities for evaluating this entity, the first being the method of choice for meningoencephalcele diagnosis although bone defects are best depicted on CT scan. CT cisternography identifies the specific site of leak and confirms benign intracranial hypertension, consistently reported in meningoencephaloceles. Obesity and benign intracranial hypertension have been reported as a combined mechanism allegedly contributing to meningoencephaloceles through congenital skull base defects, by increasing intraabdominal pressure thus decreasing venous return, with augmented intracranial pressure and subsequent reduced absorption of the CSF.

A modification of endoscopic endonasal approach for management of encephaloceles in sphenoid sinus lateral recess

Spontaneous cerebrospinal fluid leak with meningoencephaloceles in sphenoid sinus lateral recess is challenging. Transnasal visualization of this area is difficult, especially when large pneumatization is present. External approaches to this region involve aggressive surgery and are often associated with significant morbidity. The aim of this study is to assess the real effectiveness of a modification of the endoscopic endonasal approach for their management. This is a prospective case series study and was conducted at Otolaryngology department, Ain Shams University Hospitals, Cairo, Egypt. Seven patients with spontaneous cerebrospinal fluid leak with meningoencephaloceles in the sphenoid sinus lateral recess were included. Diagnosis was confirmed by: analysis for beta-2 transferrin and imaging. They were managed with endoscopic endonasal retrograde trans-sphenoid approach described in this study with multilayered reconstruction of the defect. Mean age of our patients was 40.14 ± 8.35 years; mean BMI was 36.37 ± 2.59 kg/m². Primary empty sella was present and osteodural defect was identified in superior wall of sphenoid sinus lateral recess with punched out and regular smooth edges. Mean intra-cranial pressure was (26.42 ± 3.87 mmH₂O) and size of defect was less than 10 mm, mean 7.85 ± 1.34. Mean-operative time was 169.28 ± 21.87 min. The mean hospital stay was 7.42 ± 1.39 days. No cerebrospinal fluid leak recurrences were observed during follow-up period that ranged from 37 to 48 months. Endoscopic endonasal retrograde trans-sphenoid approach provides a wide, safe, and direct route to the management of sphenoid sinus lateral recess cerebrospinal fluid leak.

Endoscopic surgery for congenital basal meningoencephaloceles in children

Conclusions Endoscopic surgery is safe and effective for children with congenital basal meningoencephaloceles (CBMs); it provides an acceptable operative outcome with a short recovery time and fewer complications and may be considered as a primary approach. Objectives To explore the safety and effectiveness of using transnasal or transoral endoscopic surgery on children with CBMs. Methods The clinical data of eight CBMs children who underwent transnasal or transoral endoscopic surgery in a hospital from January 2011 to January 2015 were collected. The presenting symptoms, lesion locations, surgical outcomes, and complications were examined retrospectively. Results Of the eight children, five (62.5%) patients were male, and their ages ranged from 1 year and 6 months to 14 years (median of 9 years). Six patients presented with the transethmoidal sub-type, and two presented with the transsphenoidal sub-type. The average hospital stay of all patients was 8.6 ± 2.6 days. There were neither intra-operative nor post-operative complications observed in any of the cases during the follow-ups that occurred between 6-54 months (mean of 15.5 months).

Meningocele and Meningoencephalocele of the Lateral Wall of Sphenoidal Sinus: The Role of the Endoscopic Endonasal Surgery

BACKGROUND

Meningocele and meningoencephalocele of the lateral wall of the sphenoidal sinus (LWSS) are rare lesions, crossing the borders of multiple disciplines such as ear-nose-throat, maxillofacial, and neurologic surgery. We reviewed our surgical experience to analyze the role of the endoscopic endonasal approach and consider these pathologies from different perspectives.

METHODS

All consecutive cases of meningocele and meningoencephalocele of LWSS operated through an endoscopic endonasal approach from 1998 to 2015 in our institutions were collected. Medical history, focusing on previous episodes of cerebrospinal fluid leak, meningitis or seizures, was considered. The outcome was assessed considering the medical condition and the postoperative neuroimaging.

RESULTS

The series includes 23 patients (7 male, 16 female). Mean age was 52 years (26-73 years). Eleven cases were meningoencephaloceles and 12 meningoceles. A clear cerebrospinal fluid leak occurred on in 19 patients and was associated with meningitis in 3. Two were presenting a history of epilepsy. No complications were observed, but 1 case presented seizures on waking. At follow-up (mean 84 months, 4-167) each patient is in good clinical condition with no further episodes of leaking or seizures.

CONCLUSIONS

Endoscopic endonasal surgery is a safe and effective approach for meningocele and meningoencephalocele of LWSS; it allows resection of herniated tissue and repair of the osteodural defect. The favorable clinical outcome and the possible effectiveness on seizures lead us to support this approach as first minimally invasive treatment also in presence of epilepsy, as a first low risk epilepsy surgical procedure.

Ethmoidal encephalocele associated with cerebrospinal fluid fistula: indications and results of mini-invasive transnasal approach

Anterior skull base defects with encephalocele in adults are quite rare and can be a cause of spontaneous rhinoliquorrhea; however, cerebrospinal fluid (CSF) fistula can be not rarely misdiagnosed for several months or years. Five adult patients affected by ethmoidal encephalocele with CSF fistula were treated in our institute from 2006 through to 2011. Onset of clinical history was represented by rhinoliquorrhea, which was precociously recognized in only 1 patient; in the other 4, it was misdiagnosed for a period ranging from 11 months to 5 years. After clinical diagnosis of CSF fistula and after brain magnetic resonance imaging, ethmoidal encephalocele was evident in all patients; preoperative study was completed by spiral computed tomography scan, to clearly identify the skull base bone defect. All patients were operated on by transsphenoidal endonasal endoscope-assisted microsurgical approach through 1 nostril. The herniated brain was coagulated and removed, and reconstruction of cranial base was performed. Postoperative rhinoliquorrhea or other complications did not occur in any patient at short and late follow-up. All patients were discharged after a few days. Endonasal endoscope-assisted microsurgical approach was effective in exposing and repairing the ethmoidal bone defect; tridimensional vision and wide lateral and superior exposition of the operative field were possible in each patient, thanks to the use of microscope and angulated endoscope.

Spontaneous sphenoid sinus cerebrospinal fluid leak and meningoencephalocele - are they due to patent Sternberg's canal?

Sternberg's canal is a congenital bony defect in the lateral wall of the sphenoid sinus. If it persists to adulthood, it may become a source of spontaneous cerebrospinal fluid leak (CSF) and meningoencephalocele. The aim of the study was to describe the authors' experience and review articles related to spontaneous sphenoid sinus CSF leaks and Sternberg's canal. We analysed patients managed surgicallly due to sphenoid sinus CSF leak and performed a PubMed database search. Two female patients with spontaneous CSF leak of sphenoid origin were found. Both patients underwent surgery with the endoscopic endonasal approach, and the defect was closed using the multi-layer technique. Twelve articles related to CSF leaks of sphenoid origin (due to Sternberg's canal) were found in the PubMed database. Lines of lesser resistance within sphenoid bone may underlie CSF leak pathology together with intracranial hypertension. The endoscopic transnasal approach to the sphenoid sinus is an excellent alternative to standard transcranial procedures.

Endoscopic transpterygoid approach and skull base repair after sphenoid meningoencephalocele resection. Our experience

INTRODUCTION AND OBJECTIVES

Cerebrospinal fluid leaks associated to meningoencephaloceles of the sphenoid lateral recess are rare entities. A congenital bony defect at this level results in the persistence of Sternberg's canal, or a lateral craniopharyngeal canal, which is supposed to be the origin of these lesions. Our objective was to show that the endoscopic transpterygoid approach is an effective technique for their treatment.

METHODS

We present a series of 5 cases of meningoencephaloceles of the sphenoid lateral recess treated with endoscopic sinus surgery (4 women and one man; mean age=59, range 37-72 years). Cerebrospinal fluid rhinorrhoea was present in all of them and they all underwent a transpterygoid approach with reconstruction of the skull base. We describe the surgical technique and review the literature.

RESULTS

No complications were observed during surgery or the postoperative period. After a mean follow-up of 81 months, only one recurrence was seen.

CONCLUSIONS

The transpterygoid approach has proven to be effective for the treatment of meningoencephaloceles of the sphenoid lateral recess. Providing wide access to identify the defect, followed by meningoencephalocele ablation, is the key for successful surgery.

Lateral sphenoid sinus recess cerebrospinal fluid leak: a case series

The lateral recess of the sphenoid sinus is one of the most common sites of meningocele and spontaneous cerebrospinal fluid (CSF) leak. Despite the availability of several techniques for closure of skull base defects occurring in this location, recurrence still poses a major challenge. This report reviews the experience of surgical repair of lateral sphenoid sinus recess CSF leak at a tertiary referral center and provides a brief discussion of this rare lesion. Nine surgeries were performed for six cases of spontaneous lateral sphenoid sinus recess CSF leak (two revisions and one repair of a new defect). Two patients presented with intracranial hypertension (ICH) and four with meningocele or meningoencephalocele. The transpterygoid approach was used in two procedures. A multilayer graft was used in seven cases and a nasoseptal flap in two. Three patients received lumbar or ventricular shunts, and one received acetazolamide for ICH management. Two minor complications were recorded, and the overall surgical success rate was 78 %. We conclude that nasoseptal flaps are a valid option for repair of recurrent CSF leaks, particularly in the lateral sphenoid sinus recess. Furthermore, identification and correction of ICH plays an essential role in the success of treatment in this patient population.

Unusual presentation of an asymptomatic pseudomeningocele within the sphenoid sinus

OBJECTIVE

We report the rare case of a 55-year-old woman with an asymptomatic left sphenoid sinus pseudomeningocele mimicking a mucocele.

CASE REPORT

A 55-year-old woman was found to have an incidental mass in the left sphenoid sinus on computed tomography. Magnetic resonance imaging confirmed the presence of a mucocele. A left endoscopic sphenoidotomy was performed to drain the mucocele. Despite an anatomical puncture through a stenosed sphenoid ostium, alarmingly, the opening leaked cerebrospinal fluid. A dehiscent lateral wall was identified with a dural opening communicating with the sphenoid sinus. This was immediately repaired with a free nasal septal mucosal graft. Six months post-operatively, the patient remained free from cerebrospinal fluid leakage.

CONCLUSION

Pseudomeningoceles are extremely rare in the absence of trauma or iatrogenic injury. Surgeons should be alert to their presence as they can mimic a unilateral mucocele or nasal polyp. Endoscopic management lends itself to a single-stage repair.

Pathophysiology and treatment options in trigeminal meningoceles

Trigeminal meningoceles, lateral to the maxillary nerve (V2), have seldom been reported as underlying pathology for spontaneous rhinoliquorrhea. In contrast to sphenoid meningoceles arising from a persistent lateral craniopharyngeal canal (Sternberg-Cruveilhier, medial to V2), their occurrence seems to be generated by addition of erosive processes to the constitutively thin bony shell underneath the semilunar ganglion, lateral to the round foramen (and V2). The developmental and anatomical relationships of trigeminal meningoceles to the sphenoid bone are depicted, and in a review of the literature we present the different surgical approaches employed for sealing the dura leak. In view of these techniques we discuss an unusual case of therapy-resistant rhinoliquorrhea with left-sided trigeminal meningocele involving the Meckel cave at the lateral sphenoid and reaching the superior orbital fissure and the medial orbital space. In contrast to patients who have lateral sphenoidal meningoceles with a persistent lateral craniopharyngeal canal (Sternberg-Cruveilhier), who can be treated successfully using an endoscopic transsphenoidal approach (recurrence rate 13.7%), the recurrence rate of cerebrospinal fluid (CSF) efflux for trigeminal meningoceles lies much higher (endoscopically 66%, open craniotomy 33%). The surgical strategy thus has to be chosen individually, taking into account specific anatomical situations and eventually preceding operations.

Rathke's pouch remnant and its regression process in the prenatal period

OBJECTS

During ontogeny, part of Rathke's pouch, a physiologically superior pouching of the stomodeal ectoderm, may remain, forming the usual anomaly known as Rathke's cleft cyst. More rarely, however, the entire pouch (i.e., the craniopharyngeal canal) remains, resulting in transsphenoidal meningoencephalocele. This study is aimed to provide a better understanding of the pathogenesis.

MATERIALS AND METHODS

We histologically evaluated the inferior protrusion of the putative hypophysial fossa in 35 embryonic and fetal heads, respectively (15 at 5-8 weeks and 20 at 12-16 weeks of gestation).

RESULTS

In 3 of the 35 specimens, we observed a complete cleft originating from the adenohypophysis, passing through the sphenoid and connecting with the pharyngeal epithelium or pharyngobasilar fascia. In another 18 specimens, we observed a duct-like structure protruding from the fossa and ending in the sphenoid. The sellar protrusion contained vein-like structures and debris of red blood cells. The protrusion was located on the anterior or anterosuperior side of the notochord. No ossification center was observed around the sellar region of the embryos. Although ossification occurred in 12 of the 20 fetuses, nine of the latter showed no evidence of cleft or protrusion, indicating that the incidence of Rathke's pouch remnant was lower in the fetuses (11/20) than in the embryos (11/15).

CONCLUSION

Rathke's pouch may be closed by ossification of the sphenoid, but increased cell proliferation and/or large amounts of degenerated veins may provide a structure resistant to the mechanical pressure caused by ossification.

Closed Meningo(encephalo)cele: a new feature in Hunter syndrome

BACKGROUND AND PURPOSE

Hunter syndrome (MPS type II) is a rare X-linked recessive disease caused by lysosomal enzyme iduronate-2-sulfatase deficiency, characterized by frequent and variable brain and skull involvement. Our objective was determine the frequency of closed cephaloceles in a large cohort of subjects affected with Hunter syndrome and to investigate possible correlations with clinical and neuroradiologic findings.

MATERIALS AND METHODS

Brain MR imaging of 33 patients (32 males and 1 female, age range 2.5-30.8 years, mean age 10.4 years) affected with Hunter syndrome were retrospectively evaluated. Eleven (age range 3.6-30.8 years; mean age 15.1) presented with an "attenuated" phenotype, while 22 (age range 2.5-19.1 years; mean age 8.2) had a "severe" phenotype.

RESULTS

A closed cephalocele was detected in 9/33 patients (27%) at the level of anterior and middle fossa in 6 and 3 cases, respectively; 6/9 subjects were affected with the attenuated phenotype and 1/9 suffered from epilepsy. Closed cephaloceles did not show a significant association with other brain and spine MR imaging features of Hunter disease, such as enlargement of perivascular spaces, cisterna magna, pituitary sella, ventricles and subarachnoid spaces, craniosynostosis, dens hypoplasia, white matter abnormalities, spinal stenosis due to periodontoid cap, platyspondylia, or intervertebral disk anomalies.

CONCLUSIONS

Closed cephaloceles are frequent in Hunter syndrome and should be considered a neuroradiologic feature of this disease.

An unusual cause of nasal airway obstruction in a neonate: trans-sellar, trans-sphenoidal cephalocoele

Introduction:

Neonates are obligate nasal breathers, and nasal obstruction may have serious implications. We present an extremely rare cause of neonatal nasal obstruction, and its management.

Case report:

An eight-day-old neonate was referred for upper airway obstruction. Initial investigations had identified no obvious cause. Rigid airway endoscopy revealed a large, cystic lesion appearing to arise from the roof of the posterior nasal space. Computed tomography and magnetic resonance imaging indicated a basal cephalocoele projecting inferiorly into the oropharynx, with an intracranial connection to the pituitary fossa. Histology showed fibrovascular tissue lined on one aspect by respiratory type epithelium, with mucous glands present. The tissue contained multiple cystic spaces lined by choroid plexus epithelium, with glial tissue present in the walls of the mass. A transpalatal excision of the nasopharyngeal cephalocoele, with closure of the intracranial connection, palatal repair and lumbar drain placement was undertaken. Post-operative recovery was uneventful, with no evidence of cerebrospinal fluid leakage or palatal dysfunction.

Conclusion:

This surgical approach gave excellent access whilst avoiding the obvious morbidity associated with an intracranial approach. Nasal masses should be considered in the differential diagnosis of neonatal respiratory distress due to nasal obstruction.

A case of sphenoid sinus meningoencephalocele repaired by an image-guided endoscopic endonasal approach

We report a Japanese patient with a complaint of unilateral watery nasal discharge. Analysis of the nasal discharge showed it to contain high levels of sugar and transferrin, which indicated cerebrospinal fluid (CSF) rhinorrhea. A diagnosis of sphenoid sinus meningoencephalocele was easily made on the basis of the CT, MRI and nasal discharge findings. We performed surgery by an image-guided endoscopic endonasal approach (IGEEA). An image guidance system (IGS) was used to confirm the position of the bone defect and the prolapsed brain lobe. We resected the brain lobe, and used fat tissue and fascia to create an extracranial-intracranial blockade. As of 18 months after the operation, there is no evidence of infection or CSF leakage. The IGEEA enabled us to successfully repair the middle skull base using a multi-layer sealing technique, while the IGS allowed us to confirm the anatomical structures and successfully avoid causing collateral damage to the surrounding tissues. This case exemplifies the beneficial effect that of the development of surgical support equipment on the operative approach that is now indicated for sphenoid sinus meningoencephaloceles: the endonasal approach has largely replaced other approaches, such as lateral rhinotomy.

Sternberg's Canal and the Controversies Surrounding It

Introduction

Although Maxmillan Sternberg described this anatomical entity (the lateral craniopharyngeal canal or the Sternberg's canal) as far back as in 1888, it has only recently stirred much controversy in world medical literature.

Materials and methods

A review of contemporary world literature on this subject has been made and applied to the authors’ personal surgical experience of managing 21 spontaneous cerebrospinal fluid (CSF) leaks over a period of 6 years, with special focus on lateral sphenoid CSF leaks, in an attempt to understand their philosophy and clinical course.

Results

Due to the rarity of such spontaneous CSF leaks (in all the published world series as well as the authors’ personal experience), it is difficult to comment on the exact site of congenital ‘weakness’, i.e. Sternberg's canal. Similar body profiles of all the patients in most series further complicates the scenario.

Conclusion

While one school of thought based on clinical and cadaveric studies hypothesizes, the Sternberg's canal to be present lateral to the foramen rotundum, the other based entirely on radiological analysis of 1000 CT scans of the paranasal sinuses proposes it to be medial to the foramen rotundum. Most patients with lateral sphenoid sinus CSF leaks (in world literature as well as the authors’ personal experience), are obese middle-aged women irrespective of whether the leak arises medial or lateral to the foramen rotundum. Thus, two strong and valid theories as regards the origin and existence (in adult life) of the Sternberg's canal are present and a multicentric, combined clinicoradiological, meta-analytical approach may probably serve as a solution to this controversy.

Middle fossa approach to a temporosphenoidal encephalocele -technical note-

Temporosphenoidal encephalocele (TSE) is a rare entity caused by herniation of the anteromedial temporal lobe into the sphenoid sinus (SS) through a middle fossa (MF) defect. A 45-year-old woman presented with a spontaneous TSE manifesting as a 4-year history of recurrent cerebrospinal fluid rhinorrhea and meningitis. Coronal computed tomography showed a skull defect in the superior wall of the right lateral recess of the SS. This homogeneous intrasphenoidal lesion appeared hypointense on T(1)-weighted magnetic resonance (MR) imaging and hyperintense on T(2)-weighted MR imaging. The patient underwent a frontotemporal craniotomy and extradural MF exploration. The encephalocele was amputated and the temporal base dura primarily sutured and reinforced with fat graft. The MF hole was plugged with temporalis fascia and a calvarial graft layered over the bone defect. Histological examination confirmed meningoencephalocele. Rhinorrhea resolved and the patient remained asymptomatic. Resection of an anteromedial TSE and closure of the craniodural defect in the MF floor via a less invasive extradural skull base approach is effective.

Spontaneous cerebrospinal fluid rhinorrhea: a clinical and anatomical study

OBJECTIVES/HYPOTHESIS

Spontaneous nasal cerebrospinal fluid (CSF) fistula represents a rare clinical entity. The possible etiology and the localization of the rhinorrhea remain an ongoing clinical challenge. The purpose of this study was to evaluate the localization of spontaneous CSF fistula and to correlate it with anatomical studies.

STUDY DESIGN

Retrospective clinical study, prospective anatomical study.

METHODS

Twenty-nine patients with spontaneous CSF rhinorrhea were retrospectively studied, 10 males and 19 females. Ages ranged from 10 to 92 years (mean, 50 years). In addition, 48 human skulls from newborns to adults were examined for the postnatal development of the anterior and middle cranial fossa.

RESULTS

In our study isolated cribriform plate defects were found in four patients. The lateral lamina of the ethmoid bone showed defects in three patients. In nine patients the bony defect could be found in the region of the fovea ethmoidalis. The bony defect between the extra- and intracranial space was found in the lateral recess of the sphenoid sinus in eight patients. Five patients had special sites (e.g., supraorbital recess and frontal recess).

CONCLUSIONS

This study supports the theory that bony dehiscence in the lateral lamina of the ethmoid bone can be congenital and can also be spontaneously acquired later. The bony dehiscence in the lateral wall of the sphenoid sinus can only develop during pneumatization.

Transsphenoidal meningoencephalocele associated with cleft lip and palate: challenges for diagnosis and surgical treatment

PURPOSE

The aim of this study was to highlight the challenges for early diagnosis and the difficulties observed in surgical treatment of patients with transsphenoidal meningoencephalocele associated with cleft lip and/or palate.

METHOD

We evaluated six male patients treated over the course of 4 years. Five patients presented encephalic herniation with nonfunctional brain tissue; one of these presented herniation of the pituitary gland and cerebral ventricles.

RESULTS

All the patients received surgical treatment for the cleft lip and/or palate. Only one patient underwent repair of the meningoencephalocele, via nasal endoscopy. There were no postprocedural clinical or surgical complications.

CONCLUSION

The tendency is to avoid neurosurgery, opting for periodic follow-up with magnetic resonance imaging. In the presence of cleft palate, palatoplasty is essential to protect the meningoencephalocele.