Sternberg's Canal Research Articles

Surgical management of a lateral sphenoid sinus encephalocele: 2-Dimensional operative video

Encephaloceles are considered rare with an approximate incidence of 1 in 35,000, and sphenoid encephaloceles are even more uncommon.2 Two types of sphenoid encephaloceles exist: medial perisellar encephaloceles, and lateral sphenoidal encephaloceles. Surgical correction of the lateral sphenoid recess encephalocele is achieved via one of two endoscopic approaches: extended sphenoidotomy or transpterygopalatine. Extended sphenoidotomy is preferred if the angle between the access door and lateral extension of bone defect is greater than 35°1. Otherwise, the transpterygopalatine approach is used. Intraoperative video demonstrating an extended sphenoidotomy approach to correcting a lateral recess sphenoidal encephalocele has not previously been published.Here we present a case of a 41-year-old female who presented with meningitis, a cerebrospinal fluid leak, and an incidental sphenoid mass. Brain MRI redemonstrated the mass in the sphenoid sinus consistent with an encephalocele occupying Sternberg's Canal. The patient consented to the procedure. The video demonstrates the skull base approach, encephalocele extraction, collagen inlay, and nasal septal bone and vascularized pedicled nasoseptal flap placement. Postoperative imaging confirmed the placement of the collagen inlay and nasal septal bone autograft. The patient recovered from surgery and was discharged on post-operative day 3 with no cerebrospinal fluid (CSF) leak recurrence. Postoperative follow up demonstrated viable nasoseptal graft without evidence of CSF leak.For patients with favorable anatomy, an extended sphenoidotomy approach to lateral sphenoid sinus encephalocele resection is a preferred alternative to the transpterygoid approach. This surgical video demonstrates the technique for managing lateral sphenoid sinus encephaloceles occupying Sternberg's canal, including endonasal approach, encephalocele resection and posterior sphenoid wall repair.

Encephalocele within the Lateral Wall of the Sphenoid Sinus Presenting with Recurrent Meningitis and Cerebrospinal Fluid Rhinorrhea Repaired via Endoscopic Transnasal Transpterygoid Approach

AbstractThe sphenoid sinus is an uncommon site for an encephalocele. It usually presents with cerebrospinal fluid (CSF) leak through the nasal cavity. Sternberg's canal (SC), which is a weak spot on the skull base, is one of the causes of spontaneous CSF leak. It is due to incomplete fusion of the greater wing of the sphenoid bone with the basisphenoid. Repairing these defects is challenging as the traditional external approach carries a high morbidity and a high complication rate. We present the case of a 27-year-old nonobese female patient who was diagnosed with persistent SC defect, which was repaired via an endoscopic transnasal transpterygoid approach. She has not had any recurrence following 18 months of outpatient department visits.

Sternberg's Canal and Defect: Is the Lateral Craniopharyngeal Canal a Source of Spontaneous Cerebrospinal Fluid Leak? Anatomic and Radiological Analysis in Pediatric and Adult Populations.

The lateral craniopharyngeal or Sternberg's canal (SC) originates from superior orbital fissure (SOF) and traverses the sphenoid body into the nasopharynx. A remnant of the canal, Sternberg's defect (SD), has been debated as a source of cerebrospinal fluid (CSF) leak. The canal was described in 1888, and there is limited accurate visual illustration in the literature. To provide a detailed anatomic and radiological illustration of the canal in pediatric and adult population including the mechanism undermining the incidence of the canal, and the possibility of the canal as a source of CSF leak. A total of 195 high-resolution computed tomographies (CT) of patients (50 3-yr-old, 20 5-yr-old, and 125 adults) and 43 dry adult skulls (86 sides) were analyzed for a canal matching the description of the SC. A SC was identified in 86% of the 3-yr-old and 40% of 5-yr-old patients. The diameter and length were 2.12 mm and 12 mm, respectively. The incidence of the canal decreased with age as sinus pneumatization extended into the sphenoid sinus. Only 0.8% of the adult skull on CT had the canal. The canal was not present on the dry adult skulls examination, but SD was found in 4.65%. SC exists with high incidence in the pediatric group. Sinus pneumatization obliterates the canal in the adult population, leaving a defect in 4.65% of cases, which given the location and related anatomic structures, is unlikely to be a source of CSF leak.

Low incidence of true Sternberg's canal defects among lateral sphenoid sinus encephaloceles.

Spontaneous sphenoid sinus cerebrospinal fluid (CSF) encephaloceles have been postulated to arise from a persistent Sternberg's canal. However, recent evidence has questioned this embryological etiology. We examined the anatomic location of a series of lateral sphenoid sinus encephaloceles to determine if they corresponded with the location of Sternberg's canal. We queried a prospectively acquired database of surgically treated spontaneous CSF leaks and identified those arising from the sphenoidal sinus. Images were reviewed to characterize the leaks with respect to the foramen rotundum (FR) and the vidian canal (VC). Four leak types were classified of which Type I (medial to FR and VC entering nasopharynx) was theoretically located in the precise location of Sternberg's canal. Type II was medial to FR; Type III was lateral to FR; Type IV passed through an enlarged FR into sphenoid sinus. Demographic data were analyzed. Of 103 repaired CSF leaks, 17 arose from the lateral sphenoid sinus. There were no true Type I leaks, 3 Type II leaks, 12 Type III leaks, and 2 Type IV leaks. No differences were found with respect to sphenoid pneumatization, BMI, age, sex, arachnoid pits, or postoperative leak between different types. No evidence was found to support the existence of a classic Sternberg canal CSF leak, supporting the hypothesis that most sphenoid spontaneous leaks likely occur secondary to chronically elevated ICP. Rare cases may be related to a weakness in the sphenoid wall in the region of Sternberg's canal.

Endoscopic Transpterygoid Approach and Skull Base Repair After Sphenoid Meningoencephalocele Resection. Our Experience

Introduction and objectivesCerebrospinal 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. MethodsWe 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. ResultsNo complications were observed during surgery or the postoperative period. After a mean follow-up of 81 months, only one recurrence was seen. ConclusionsThe 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.

Abordaje endoscópico transpterigoideo y reparación de base de cráneo tras resección de meningoencefalocele esfenoidal. Nuestra experiencia

Introduction and objectivesCerebrospinal 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. MethodsWe 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. ResultsNo complications were observed during surgery or the postoperative period. After a mean follow-up of 81 months, only one recurrence was seen. ConclusionsThe 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.

Spontaneous sphenoid lateral recess cerebrospinal fluid leaks arise from intracranial hypertension, not Sternberg's canal

Spontaneous cerebrospinal fluid (CSF) leaks/encephaloceles are proven to be associated with intracranial hypertension by objective measurements of CSF pressure during or following endoscopic repair. A common area of involvement is a pneumatized lateral recess of the sphenoid (LRS) sinus, where prolonged intracranial pressures lead to arachnoid pits and subsequent development of skull-base defects. Even though the LRS is never present at birth, a "congenital" cause of these leaks due to a persistent Sternberg's (lateral craniopharyngeal) canal continues to be erroneously perpetuated in the literature. The objective of this study was to eliminate the myths defining these leaks as congenital in nature. Evaluation of LRS CSF leaks present within a multiinstitutional case series was performed. Data regarding demographics, body mass index (BMI), radiologic evaluation of intracranial hypertension, and direct intracranial pressure measurements (when available) were collected. Data evaluation identified 77 LRS CSF leaks in 59 patients (mean age 52 years). Obesity was present in 83% of individuals (mean BMI 36) and 81% were females. Radiologic evidence of intracranial hypertension (eg, empty sella, dilated optic nerve sheaths, and scalloped/attenuated bone) was present on 96% of preoperative computed tomography (CT) and/or magnetic resonance imaging (MRI) scans. Opening or postsurgical lumbar drain or ventriculostomy pressure measurements were elevated in 95% of patients (mean 27.7; range, 9-50 cmH2 O). This study provides objective evidence that LRS CSF leaks are secondary to erosions from intracranial hypertension and refutes the myth regarding a congenital origin from Sternberg's canal.

Glial Heterotopia of Sphenoid in Association with a Patent Sternberg's Canal presenting with Meningitis

ABSTRACTEctopic glial tissue, presenting at various sites of body is a rare embryonic developmental anomaly. Very few cases are reported in adults, most being incidentally detected, revealed only by histopathological findings. One of the rarest locations is the sphenoid sinus.We present here the case of a middle aged female, presenting with spontaneous cerebrospinal fluid (CSF) rhinorrhea and meningitis. With the radiological finding of a soft tissue density in sphenoid sinus with erosion of left temporal skull base, she underwent lateral craniotomy, with excision of the mass and middle cranial fossa floor repair. Histopathology revealed a heterotopic glial tissue. Peroperative finding of a well-defined defect in the lateral wall of an extensively pneumatized sphenoid showed typical features of a patent Sternberg's canal.This case could be a living proof for the existence of this rare developmental anomaly. A persisting Sternberg's canal should be considered as the source of spontaneous CSF leaks with or without lesions in sphenoid sinuses with extensive lateral pneumatization. Most of the cases may be treated with an extended endoscopic approach. Extreme lateral lesions like this would benefit most from a craniotomy approach for proper closure of skullbase defect. Three years after successful surgery, she remains symptom free.How to cite this articleSuma R, Jeena KJ, Pavithran VM, Govindan A, Ramachandran K. Glial Heterotopia of Sphenoid in Association with a Patent Sternberg's Canal presenting with Meningitis. Int J Otorhinolaryngol Clin 2014;6(2):81-83.

Frustrane Duraplastiktechnik oder persistierender/rekanalisierter Sternberg Kanal der Keilbeinhöhle?

Spontaneous rhinoliquorrhea with or without meningo-encephaloceles in the region of the sphenoid sinus occurs very infrequently. It is not uncommon that the attempt of transnasal endoscopic duraplasty in this region leads to recurrence of the CSF leak. The existence of a lateral craniopharyngeal canal can be a possible explanation for these failures.Retrospective analysis of 23 patients with rhinoliquorrhea of different pathogenesis in the region of the frontal and central skull base that were treated with transnasal, video-endoscopic surgical procedures in our department between 2006 and 2011.2 of 23 patients with proven rhinoliquorrhea following a transnasal video endoscopic duraplasty procedure showed a recurrence of the CSF leak. The computertomographic analysis with respect to the current literature indicated the presence of a craniopharyngeal canal at the lateral side of the sphenoid sinus. This canal is also known in the literature as Sternberg's canal. In contrast to the other 21 treated cases there were no planar skull base defects of different pathogenesis in these 2 cases, but a ontogenetically bony canal. The canal can reopen spontaneously or due to an external mechanical impact.The closure of this bony canal requires a modified surgical procedure such as sufficient padding of the bony canal and its sealing by a vascularized pedicle flap in contrast to the ordinary planar bony skull base defects.

Glial Heterotopia of Sphenoid in Association with a Patent Sternberg's Canal presenting with Meningitis

ABSTRACT Ectopic glial tissue, presenting at various sites of body is a rare embryonic developmental anomaly. Very few cases are reported in adults, most being incidentally detected, revealed only by histopathological findings. One of the rarest locations is the sphenoid sinus. We present here the case of a middle aged female, presenting with spontaneous cerebrospinal fluid (CSF) rhinorrhea and meningitis. With the radiological finding of a soft tissue density in sphenoid sinus with erosion of left temporal skull base, she underwent lateral craniotomy, with excision of the mass and middle cranial fossa floor repair. Histopathology revealed a heterotopic glial tissue. Peroperative finding of a well-defined defect in the lateral wall of an extensively pneumatized sphenoid showed typical features of a patent Sternberg's canal. This case could be a living proof for the existence of this rare developmental anomaly. A persisting Sternberg's canal should be considered as the source of spontaneous CSF leaks with or without lesions in sphenoid sinuses with extensive lateral pneumatization. Most of the cases may be treated with an extended endoscopic approach. Extreme lateral lesions like this would benefit most from a craniotomy approach for proper closure of skullbase defect. Three years after successful surgery, she remains symptom free.

Intrasphenoidal Meningo-encephalocele: Report of two rare cases and review of literature

Background:Transsphenoidal encephaloceles represent a rare clinical entity with wide range of symptoms in adult. Such lesions require accurate diagnosis and surgical treatment. The incidence of congenital encephalocele is very low occurring in approximately 1 in 3000-5000 live births. Even though 63 similar cases have been reported in the literature not all of them have been discussed completely. Due to the rare occurrence of these lesions, we will focus on the main clues in the diagnosis and management of such lesions, which are challenging.Case Description:We intend to present our experience with two cases of trans-sphenoidal meningoencephalocels, one located medially and the other herniating through the Sternberg's canal. The younger was 17 and the elder was 47 years old and both of them presented with cerebrospinal fluid (CSF) leakage. Both patients were treated successfully using pure endoscopic endonasal approach.Conclusion:Ideal surgical approach for such patients is still not clear due to lack of adequate experience in the literature, it is suggested that full preoperative imaging studies might lead the surgeons to undertake minimally invasive skull base approaches in similar patients.

Association Between Cerebrospinal Fluid Leakage and Persistence of Sternberg's Canal: Coincidence or Cause?

Endoscopic surgical techniques allow treating various pathological diseases of the cranial base, including cerebrospinal fluid leaks (CSF). These approaches have a high success rate and reduce surgical time and morbidity. However, when they are located in the lateral wall of the sphenoid, the surgery is more complex. In our case, the CSF appeared to be related with a Sternberg's canal. Predisposing factors were also associated with an extensive unilateral pneumatization of the sinus and benign intracranial hypertension. The closure of the leak was achieved using an endoscopic transethmoidal transpterygoid approach for proper exposition of the lateral wall of the sphenoid. After 5 years of monitoring, the patient has had no more episodes of rhinoliquorrhea.

Endoscope-Assisted Trans-Sphenoidal Approach for Treatment of Sternberg's Canal

We report an uncommon case of a 45-year-old woman who presented with spontaneous rhinorrhea. A computed tomography (CT) scan of the head revealed an abnormally large sphenoid sinus associated with a parasellar bony defect (Sternberg's canal) through which magnetic resonance imaging could detect an encephalocele of the right temporal lobe. An endoscope-assisted trans-sphenoidal approach was performed and, with the aid of image guided surgery, reduction of the encephalocele was obtained and followed by surgical repair of the dural and bony defects. The postoperative course was uneventful and the cerebrospinal fluid fistula was closed as confirmed by the postoperative CT scan and by the absence of rhinorrhea. After three years of monitoring the patient remained asymptomatic.

Asociación entre fístula de líquido cefalorraquídeo y persistencia del canal de Sternberg: ¿coincidencia o causa?

Endoscopic surgical techniques allow treating various pathological diseases of the cranial base, including cerebrospinal fluid leaks (CSF). These approaches have a high success rate and reduce surgical time and morbidity. However, when they are located in the lateral wall of the sphenoid, the surgery is more complex. In our case, the CSF appeared to be related with a Sternberg's canal. Predisposing factors were also associated with an extensive unilateral pneumatization of the sinus and benign intracranial hypertension. The closure of the leak was achieved using an endoscopic transethmoidal transpterygoid approach for proper exposition of the lateral wall of the sphenoid. After five years of monitoring, the patient has had no more episodes of rhinoliquorrhea.

Sternberg′s canal as a cause of encephalocele within the lateral recess of the sphenoid sinus: A report of two cases

Background:Intrasphenoidal encephaloceles are extremely rare findings. Sternberg's canal is a lateral craniopharyngeal canal resulting from incomplete fusion of the greater wings of the sphenoid bone with the basisphenoid. It acts as a weak spot of the skull base, which may lead to develop a temporal lobe encephalocele protruding into the lateral recess of the sphenoid sinus (SS).Case Description:We present two cases of intrasphenoidal encephalocele due to persistence of the lateral craniopharyngeal canal. The first case presented with cerebrospinal fluid (CSF) rhinorrhea and the second one was referred to the neurosurgical department with CSF rhinorrhea and meningitis. Radiological investigations consisted of computed tomography (CT) scan, CT cisternography and magnetic resonance images in both cases. These imaging studies identified a herniated temporal lobe through a bony defect which communicates the middle cranial fossa with the lateral recess of the SS. Both patients underwent a transcranial repair of the encephalocele because of the previous failure of the endoscopic surgery. There was no complication related to the surgical procedure and no recurrence of CSF leakage occurred 2 and 3 years after surgery, respectively.Conclusion:Encephalocele within the lateral recess of the SS is a rare entity which must be suspected in patients who present with spontaneous CSF rhinorrhea. Congenital intrasphenoidal encephaloceles, which are located medial to the foramen rotundum, seem to be due to persistence of the Sternberg's canal. Transcranial approach is a good option when a transnasal approach had failed previously.

Sternberg's Canal and the Controversies Surrounding It

ABSTRACTIntroductionAlthough 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 methodsA 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.ResultsDue 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.ConclusionWhile 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.

Ttranscranial approach for spontaneous csf rhinorrhea due to sternberg's canal intrasphenoidal meningoencephalocele: case report and review of literature

One type of congenital intrasphenoidal meningoencephalocele is remnant of lateral craniopharyngeal (Sternberg's) canal. We present a case of a 23-year girl with 10-month history of right side CSF rhinorrhea. CT scan, MRI revealed congenital meningoencephalocele and CSF leak from middle fossa to right side of sphenoid sinus, and there were bony defects at the floor of the anterior aspect of the right middle fossa. Transcranial repair was performed with right side pterional craniotomy. Careful preoperative evaluation and localization of the sphenoid defect are essential for selection of the best possible surgical approach and skull base reconstruction for repair of sphenoid sinus CSF leaks and meningoencephaloceles. In this case, an endoscopic technique was not successful so, transcranial repair was performed with right side pterional craniotomy.

Spontaneous CSF-leaks and meningoencephaloceles in sphenoid sinus by persisting Sternberg's canal

Cerebrospinal fluid (CSF) leaks and meningoencephaloceles of the lateral recess of sphenoid sinuses are rare findings. A congenital bony defect in the lateral wall of sphenoid sinus called Sternberg's canal could be the origin of these lesions. Their endoscopic transnasal management is challenging though less traumatic than transcranial approaches. The aim of this study was to define Sternberg's canal as a potential source for these rare lesions and to describe their endoscopic endonasal management. In a retrospective analysis clinical charts of 27 patients with CSF-leaks and / or meningoencephaloceles operated between March 2002 and October 2008 at the University ENT-hospital Graz have been reviewed. All patients were treated by an endoscopic endonasal approach. Five patients (4 female / 1 male) were identified with spontaneous CSF-leaks from sphenoid sinus and meningoencephaloceles. In all five cases, Sternberg's canal was the site of leakage, with the bony and dural defects always located laterally between the maxillary and Vidian nerves. Mean age was 51.2 years and mean body mass index (BMI) was 31.9 kg/m2. All patients were operated using a multilayer closure technique. Two patients had recurrences after 12 days and 7 months, respectively, managed by endoscopic revision surgery resulting in a 100% closure rate after one revision (mean follow-up: 6.5 months). Persisting Sternberg's canal can be the source of spontaneous CSF-leaks and meningoencephaloceles in the lateral recess of sphenoid sinus especially when associated with extensive pneumatisation. Endoscopic management is technically challenging, nevertheless its advantages are a good view of the surgical field while being less traumatic than transcranial approaches.

Sternberg's Canal: Fact or Fiction?

Sternberg's (lateral craniopharyngeal) canal was originally described in anatomic studies as a membranous space in the lateral wall of the sphenoid sinus. The canal has been etiologically associated with lateral sphenoid sinus "spontaneous" cerebrospinal fluid (CSF) leaks. A patent Sternberg's canal has been reported in up to 4% of adults, and persistent vestiges have been reported in up to 30%. However, no modern studies analyzing high-resolution CT scans have been published. A consecutive analysis of 1000 high-resolution CT scans of sphenoid bones was performed. Scans were analyzed for a lateral recess, bony defects, arachnoid pits, and holes possibly representing Sternberg's canal. Data were compared with a case series of lateral sphenoid CSF leaks. Average patient age was 38.7 years (10-92 years). A sphenoid lateral recess was present in 35.3% (17.4% bilateral) of cases. Arachnoid pits were present on the floor of the middle cranial fossa in 23.4% of cases. Seven skull base defects were identified. Only one traveling medial to V2 resembled the description of Sternberg's canal. In contrast, a case series of 25 patients with lateral sphenoid sinus CSF leaks all had a lateral recess, defects, and arachnoid pits lateral to V2 (p < 0.00001). Sternberg's canal as historically defined is not nearly as prevalent as previously reported. Furthermore, the presence of arachnoid pits in all sphenoid CSF leaks and the predominant leak location lateral to the sites of fusion of ossification centers suggests that the leaks are acquired. Contributing factors may include arachnoid pits/weaknesses in the skull base and intracranial hypertension.

Endonasal Endoscopic Repair of Sternberg's Canal Cerebrospinal Fluid Leaks

Management of cerebrospinal fluid leaks or encephaloceles of Sternberg's canal 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 the study was to assess the real effectiveness of an endoscopic endonasal approach for treating cerebrospinal fluid leaks of the lateral recess of the sphenoid sinus. The authors conducted a retrospective evaluation. Clinical charts of patients with cerebrospinal fluid leaks and/or encephaloceles of Sternberg's canal treated at our institution were retrospectively reviewed. All these patients were managed with an endonasal endoscopic procedure. Fifteen patients (9 female and 6 male) were included in this study. Nine patients underwent a transethmoidal-pterygoidal-sphenoidal approach with a multilayer reconstructive technique. No cerebrospinal fluid leak recurrences were observed during follow up (mean follow up 37.6 +/- 21.7 standard deviation months) The transethmoidal-pterygoidal-sphenoidal approach provides a wide, safe, and direct route to the lateral recess of the sphenoid sinus. Multilayered reconstruction of the skull base defects must be considered the first option for this kind of lesion.