Endoscopic Transnasal Transmaxillary Approach to Orbital Apex through the Meningo-Orbital Band: A Cadaveric Feasibility Study.

Background: Extradural transcranial release of the meningo-orbital band occupying the lateral part of the superior orbital fissure is used to approach the orbital apex and middle cranial fossa. The authors tested the feasibility of the release of the meningo-orbital band via an endonasal transmaxillary approach. Materials and Methods: Five injected cadaveric heads were assessed for dimensions of superior orbital fissure by computerized tomography. An endonasal transsphenoid transpterygoid approach was done to the superior orbital fissure and annulus of Zinn medially, down to the maxillary nerve. The periorbita was dissected superolaterally to expose the greater wing of the sphenoid and the meningo-orbital band. The superior orbital fissure was decompressed inferiorly by drilling the greater wing of the sphenoid and the maxillary strut after transposition of the maxillary nerve. The meningoorbital band was cut at the junction of the lateral part of the superior orbital fissure and the periorbita exposing the frontotemporal dural junction. The edge of the lesser wing of the sphenoid was drilled toward the annulus of Zinn and the optic canal. The temporal lobe dura was separated from the periorbita and lateral cavernous dural wall at the meningo-orbital band and the ophthalmic nerve. Results: The superior orbital fissure had an oblique angle (mean: 39 ± 2.75 degrees) to the midsagittal plane, the length of its lateral part corresponding to the meningo-orbital band was (mean: 6.08 ± 2.58 mm) and the distance from its lateral end to midline was (mean 2.97 ± 0.11 cm). The meningo-orbital band was released in 10 cadaveric head sides with a distinct plane between the periorbita and the dura propria. Transmaxillary endoscopy provided less orbital retraction and better visualization of the lateral wall of the cavernous sinus. Conclusion: Endonasal transmaxillary release of the meningoorbital band is feasible, allowing exposure of the orbital apex and the middle cranial fossa.

Microsurgery versus stereotactic radiosurgery for small petroclival meningiomas presenting with intractable trigeminal neuropathy: A historical cohort study.

Background: Data on the outcomes of microsurgical resection (SR) and stereotactic gamma knife radiosurgery (GKRS) in patients with trigeminal neuralgia associated with small petrous apex meningiomas are scarce. Objective: We conducted this study to evaluate the pain relief, tumor control, and procedure costs following SR and GKRS for small petroclival meningiomas (less than 3 cm in maximal diameter) using real-world data from our center in Egypt. Material and Methods: We conducted a retrospective cohort study of 47 patients with small petrous apex meningiomas presenting with intractable trigeminal nerve pain (SR: n = 22 and GKRS: n = 25). Data regarding pain relief on Barrow Neurological Institute (BNI), procedure cost, and tumor control were retrieved and analyzed using appropriate statistical tests. Results: Patients who underwent SR had lower median BNI pain intensity scores compared to those patients who underwent GKRS, and a significantly higher proportion of patients in the SR group had good BNI scores compared to those in GKRS group (P < 0.05); however, the total costs of SR were significantly less than GKRS (30,519$ vs. 92,372$, respectively). Conclusion: Both SR and GKRS provide pain relief and tumor control in patients with trigeminal neuralgia associated with petrous apex meningioma. However, in the present study, SR achieved better pain control and was more affordable than GKRS.

Endoscopic Endonasal Approach to the Lateral Wall of the Cavernous Sinus: A Cadaveric Feasibility Study.

OBJECTIVE:: A transcranial extradural approach to the middle cranial fossa (MCF) requires separation of the dural layers of the lateral wall of the cavernous sinus. The authors tested the feasibility of an endonasal approach for this separation. METHODS:: A cadaveric feasibility study was conducted on the sides of 14 dry skulls and 10 fresh cadaveric heads. An endonasal, transsphenoidal, transpterygoid approach was taken to the MCF. The maxillary struts and medial greater wing of the sphenoid below the superior orbital fissure were drilled with transposition of the maxillary nerve. The lateral cavernous dural layers were split at the maxillary nerve with separation of the temporal lobe dura and exposure of the MCF bony base. The integrity of the cranial nerves and inner and outer dural layers of the lateral cavernous wall was checked. Different measurements of bony landmarks were obtained. RESULTS:: The integrity of the dural layers of the lateral cavernous wall and the cranial nerves were preserved in 10 heads. The mean area of the bony corridor was 4.68 ± 0.97 cm2, the V2-to-V3 distance was 15.21 ± 3.36 mm medially and 18.21 ± 3.45 mm laterally, and the vidian canal length was 13.01 ± 3.06 mm. CONCLUSIONS:: Endonasal endoscopic separation of the lateral cavernous dural layers is feasible without crossing the motor cranial nerves, allowing better exposure of the MCF.

Role of surgery for small petrous apex meningiomas causing refractory trigeminal neuropathy in the minimally invasive era.

BACKGROUND: Radiosurgery seems to be a very appealing option for patients having a small petrous apex meningioma and presenting with trigeminal neuralgia, presumably because of the lower risk and cost involved. The aim of this study was to analyze the results of our surgical series of petrous apex meningioma presenting with trigeminal neuralgia, and to determine the efficacy of neurosurgical treatment with regard to pain control. The procedure-related complication and morbidity rates were also evaluated. MATERIALS AND METHODS: This is a retrospective study of 17 patients with a small (<3 cm) petrous apex meningioma. The included patients were refractory to medical treatment for trigeminal neuralgia and were deemed as surgical candidates. Postoperatively, the patients were assessed for pain relief according to the Barrow Neurological Institute (BNI) scale. A P value of less than 0.05 was considered significant. Magnetic resonance imaging was also performed after 6 weeks to assess the radicality of resection. RESULTS: In a median follow-up of approximately 2 years, the study showed that 14 of the 17 (82.4%) patients had complete pain relief, with very low morbidity and no mortality, and 100% tumor control. According to the Barrow Neurological Institute (BNI) scale for the assessment of postoperative pain relief, 52.9, 23.5, 5.9, 11.8, and 5.9% of patients had grades I, II, IIIa, IIIb, and IV in terms of their pain relief, respectively. CONCLUSIONS: In our population of patients, surgery proved to be successful in providing symptomatic relief, with low morbidity and no mortality, and was comparable with other studies involving the minimally invasive modalities. However, these results warrant further follow-up, with recruitment of more patients, to demonstrate whether or not, surgery should be the primary choice of treatment in this subgroup of patients.

Composite Vascular Pedicled Middle Turbinate Flap for Reconstruction of Sellar Defects.

OBJECTIVES: Herein, we describe our experience in simple harvest of the vascular pedicled middle turbinate flap (MTF) sufficient for sellar defect reconstruction. METHODS: An anatomical feasibility study is done in 10 sides of 5 preserved injected cadaveric heads. The middle turbinate is separated from the skull base and the basal lamella with or without retrograde dissection of its tail as a composite flap based on the middle turbinate and posterolateral nasal arteries. The technique was applied in 25 cases of cerebrospinal fluid (CSF) leak after endoscopic transsphenoidal surgery. RESULTS: The mean area of MTF with and without medial mucosal dissection was 9.53 cm(2) and 7.6 cm(2), respectively. The mean length between anterior end of MT and basal lamella and the latter and the sella was 3.67 cm and 2.33 cm, respectively. The mean area of sella was 2.2 cm(2). The MTF covered the sella, planum, and tuberculum sella corridors in 10 head sides. Partial dissection of MT medial mucosa was needed in 3 head sides to cover sella, planum, and tuberculum sella. Follow-up for 26 to 37 month revealed control of CSF leak in 24 cases. CONCLUSION: Composite MTF is a simple rapid reproducible option for sellar defects reconstruction.

Endoscopic orientation of the parasellar region in sphenoid sinus with ill-defined bony landmarks: an anatomic study.

The sphenoid bony landmarks are important for endoscopic orientation in skull base surgery but show a wide range of variations. We aimed to describe an instructional model for the endoscopic parasellar anatomy in sphenoid sinuses with ill-defined bony landmarks. Five preserved injected cadaveric heads and four sides of dry skulls were studied endoscopically via transethmoid, transsphenoidal approach. The parasellar region was exposed by drilling along the maxillary nerve (V2) canal [the length of the foramen rotundum (FR) between the middle cranial fossa and the pterygopalatine fossa]. This was achieved by drilling in the inferior part of the lateral wall of posterior ethmoids immediately above the sphenopalatine foramen. Cavernous V2 was traced to the paraclival internal carotid artery (ICA). Cavernous sinus (CS) apex was exposed by drilling a triangle bounded by V2 and its canal inferiorly, bone between FR and superior orbital fissure (SOF) anteriorly, and ophthalmic nerve (V1) superiorly. Drilling was continued toward the annulus of Zinn (AZ) and optic nerve superiorly and over the intracavernous ICA posteriorly. Endoscopic measurements between V2, SOF, AZ, and opticocarotid recess were obtained. Endoscopic systematic orientation of parasellar anatomy is presented that can be helpful for approaching sphenoid sinus with ill-defined bony landmarks.

Laryngopharyngeal reflux with sore throat: an ultrastructural study of oropharyngeal epithelium.

OBJECTIVES: We performed an electron microscopic ultrastructural study of oropharyngeal epithelium in patients with laryngopharyngeal reflux (LPR) and sore throat to evaluate whether dilatation of intercellular spaces could be traced at this level. METHODS: The study included 20 patients with LPR and sore throat and 5 control subjects. The patients were subjected to upper gastrointestinal tract endoscopy and flexible pharyngolaryngoscopy. Oropharyngeal biopsy specimens were taken from the patients and controls for ultrastructural study by transmission electron microscopy. RESULTS: The entire group of patients with LPR showed dilatation of intercellular spaces essentially at the squamous basal and suprabasal levels in their oropharyngeal biopsy specimens, whereas none of the control subjects showed such a morphological marker. CONCLUSIONS: Dilatation of intercellular spaces as a morphological marker can be traced in patients with LPR and sore throat at the level of the oropharynx. This contributes to a better understanding of the pathophysiology of LPR. If this finding is confirmed in a large series, it will represent a cost-effective, relatively noninvasive method for diagnosis of LPR.