Transorbital Endoscopic Approach to the Foramen Rotundum for Infraorbital Nerve Stripping.

PURPOSE: To develop and evaluate a transorbital endoscopic approach to the foramen rotundum to excise the maxillary nerve and infraorbital nerve branch. METHODS: Cadaveric dissection study of 10 cadaver heads (20 orbits). This technique is predicated upon 1) an inferior orbital fissure release to facilitate access to the orbital apex and 2) the removal of the posterior maxillary wall to enter the pterygopalatine fossa (PPF). Angulations along the infraorbital nerve were quantified as follows: the first angulation was measured between the orbitomaxillary segment within the orbital floor and the pterygopalatine segment suspended within the PPF, while the second angulation was taken between the pterygopalatine segment and maxillary nerve as it exited the foramen rotundum. With refinement of the technique, the minimum amount of posterior maxillary wall removal was quantified in the final 5 cadaver heads (10 orbits). RESULTS: The mean distance from the inferior orbital rim to the foramen rotundum was 45.55 ± 3.24 mm. The first angulation of the infraorbital nerve was 133.10 ± 16.28 degrees, and the second angulation was 124.95 ± 18.01 degrees. The minimum posterior maxillary wall removal to reach the PPF was 11.10 ± 2.56 mm (vertical) and 11.10 ± 2.08 mm (horizontal). CONCLUSIONS: The transorbital endoscopic approach to an en bloc resection of the infraorbital nerve branch up to its maxillary nerve origin provides a pathway to the PPF. This is relevant for nerve stripping in the context of perineural spread. Other applications include access to the superior portion of the PPF in selective biopsy cases or in concurrent orbital pathology.

Maxillary Nerve as Landmark for Exposure of the Internal Maxillary Artery in Extracranial-Intracranial Bypass Surgery.

OBJECTIVE: To establish a new method for fast exposure of the internal maxillary artery (IMA) during extracranial-intracranial bypass surgery. METHODS: To explore the positional relationship between the IMA and the maxillary nerve and pterygomaxillary fissure, 11 formalin-fixed cadaveric specimens were dissected. Three bone windows of the middle fossa were created for further analysis. Then the IMA length that could be pulled up above the middle fossa was measured after different degrees of removal of bony structure. The IMA branches under each bone window were also explored in detail. RESULTS: The top of the pterygomaxillary fissure was located 11.50 mm anterolateral to the foramen rotundum. The IMA could be identified just inferior to the infratemporal segment maxillary nerve in all specimens. After drilling of the first bone window, the IMA length that could be pulled above the middle fossa bone was 6.85 mm. After drilling of the second bone window and further mobilization, the IMA length that could be harvested was significantly longer (9.04 mm vs. 6.85 mm; P < 0.001). Removal of the third bone window did not significantly improve the IMA length that could be harvested. CONCLUSIONS: The maxillary nerve could be used as a reliable landmark for the exposure of the IMA in the pterygopalatine fossa. With our technique, the IMA could be easily exposed and sufficiently dissected without zygomatic osteotomy and extensive middle fossa floor removal.

Cleft Palate Repair: A New Maxillary Nerve Block Approach.

OBJECTIVE: To introduce a different approach for maxillary nerve block (MNB), in cleft palate repair. To reduce the use of opioids during surgery and to prevent frequent respiratory complications by means of an adequate intra and postoperative pain relief. PATIENTS AND METHODS: A prospective clinical trial was planned, to collect scientific evidences between 2 groups of patients with primary cleft palate, receiving surgery in 2 Pediatric centers of Buenos Aires, utilizing a different protocol.Sixty patients undergoing primary cleft palate repair in both hospitals, from January 2017 to July 2018, by senior surgeons and the same expert anesthesiologists' team, were included.Syndromic and secondary cases, and patients whose parents rejected to participate of this study were excluded. The first group called Hospital A included 45 children, the second group identified as Hospital B was formed by 15 patients.A combination of general whit local anesthesia and a bilateral regional MNB, was used in all the patients of the Hospital A. Utilizing an aspirating syringe, children received 0.15 ml/kg of lidocaine clorhidrate 2% with epinephrine 1:50.000, under direct vision through the spheno palatine holes, just before surgery. A traditional general anesthesia procedure plus local anesthesia, was utilized in all the patients treated at the Hospital B Medial blood pressure and cardiac frequency parameters were tested during induction, along the surgical procedure and in the immediate post op, to detect any sign of pain (12). After surgery, patient reactivity, airway depression symptoms, time of initial feeding and discharge time, were also monitored (13).This study was approved by the Hospitals Ethics Committees of both hospitals, and is in accordance with the 1975 Helsinki Declaration, as amended in 1983. The parents have signed an informed consent form for all the patients included. RESULTS: Patients of both groups did not show any significant variant in the monitored parameters to detect signals of pain, along the surgery. The rest of controls during and after surgery showed significant differences in favor of the patients of Hospital A. CONCLUSIONS: Bilateral regional MNB, under direct vision trough the spheno palatine holes results an effective, easy, and safe method for pain relief during and after primary cleft palate repair surgeries.The combination of slight general anesthesia with local anesthesia and regional blocks, results a good option to reduce opioids utilization, to prevent neurotoxicity, respiratory depression, sickness, and vomiting facilitating early feeding and patient discharge.

Infraorbital Foramen Decompression Surgery for the Infraorbital Nerve Hypoesthesia in Patients With Isolated Fracture of Maxillary Sinus Anterior Wall.

Isolated fracture of maxillary sinus anterior wall is relatively uncommon. If the extent of fracture is minimal, only conservative care is amenable, however, there is no agreement on whether infraorbital nerve dysfunction can be used as an indication for surgical intervention. This study was conducted to verify the effect of decompression surgery of infraorbital foramen for recovery of hypoesthesia. A total of 26 patients with unilateral fracture of maxillary sinus anterior wall were enrolled. Ten who received only conservative therapy were allocated in the control group, while sixteen patients were assigned to the decompression group. Pre- and post-treatment sensory assessment using visual analogue scale (VAS) was recorded. Overall treatment satisfaction was also evaluated by means of global assessment scale (GAS). Both absolute VAS value and score increment showed statistical difference only at 4 weeks (P = 0.010 and P = 0.021, respectively), but no significant difference at 1, 12, and 24 weeks. GAS score also showed no statistical significance (P = 0.386). Decompression surgery of infraorbital foramen does not have a significant effect on hypoesthesia recovery in isolated fracture of maxillary sinus anterior wall. Therefore, it is not recommended to perform the operation when the infraorbital nerve hypoesthesia is the only indication for the open reduction.

Tacr3 in the lateral habenula differentially regulates orofacial allodynia and anxiety-like behaviors in a mouse model of trigeminal neuralgia.

Trigeminal neuralgia (TN) is debilitating and is usually accompanied by mood disorders. The lateral habenula (LHb) is considered to be involved in the modulation of pain and mood disorders, and the present study aimed to determine if and how the LHb participates in the development of pain and anxiety in TN. To address this issue, a mouse model of partial transection of the infraorbital nerve (pT-ION) was established. pT-ION induced stable and long-lasting primary and secondary orofacial allodynia and anxiety-like behaviors that correlated with the increased excitability of LHb neurons. Adeno-associated virus (AAV)-mediated expression of hM4D(Gi) in glutamatergic neurons of the unilateral LHb followed by clozapine-N-oxide application relieved pT-ION-induced anxiety-like behaviors but not allodynia. Immunofluorescence validated the successful infection of AAV in the LHb, and microarray analysis showed changes in gene expression in the LHb of mice showing allodynia and anxiety-like behaviors after pT-ION. Among these differentially expressed genes was Tacr3, the downregulation of which was validated by RT-qPCR. Rescuing the downregulation of Tacr3 by AAV-mediated Tacr3 overexpression in the unilateral LHb significantly reversed pT-ION-induced anxiety-like behaviors but not allodynia. Whole-cell patch clamp recording showed that Tacr3 overexpression suppressed nerve injury-induced hyperexcitation of LHb neurons, and western blotting showed that the pT-ION-induced upregulation of p-CaMKII was reversed by AAV-mediated Tacr3 overexpression or chemicogenetic inhibition of glutamatergic neurons in the LHb. Moreover, not only anxiety-like behaviors, but also allodynia after pT-ION were significantly alleviated by chemicogenetic inhibition of bilateral LHb neurons or by bilateral Tacr3 overexpression in the LHb. In conclusion, Tacr3 in the LHb plays a protective role in treating trigeminal nerve injury-induced allodynia and anxiety-like behaviors by suppressing the hyperexcitability of LHb neurons. These findings provide a rationale for suppressing unilateral or bilateral LHb activity by targeting Tacr3 in treating the anxiety and pain associated with TN.

Endoscopic endonasal treatment of maxillary nerve (V2) painful neuropathy: cadaveric study with clinical correlation.

BACKGROUND: Surgical access to the second (V2, maxillary) and third (V3, mandibular) branches of the trigeminal nerve (V) has been classically through a transoral approach. Increasing expertise with endoscopic anatomy has achieved less invasive, more efficient access to skull base structures. The authors present a surgical technique using an endoscopic endonasal approach for the treatment of painful V2 neuropathy. METHODS: Endoscopic endonasal dissections using a transmaxillary approach were performed in four formalin-fixed cadaver heads to expose the V2 branch of the trigeminal nerve. Relevant surgical anatomy was evaluated and anatomic parameters for neurectomy were identified. RESULTS: Endoscopic endonasal transmaxillary approaches completed bilaterally to the pterygopalatine and pterygomaxillary fossae exposed the V2 branch where it emerged from the foramen rotundum. The anatomy defined for the location of neurectomy was determined to be the point where V2 emerged from the foramen rotundum into the pterygopalatine fossa. The technique was then performed in 3 patients with intractable painful V2 neuropathy. CONCLUSIONS: In our cadaveric study and clinical cases, the endoscopic endonasal approach to the pterygopalatine fossa achieved effective exposure and treatment of isolated V2 painful neuropathy. Important surgical steps to visualize the maxillary nerve and its branches and key landmarks of the pterygopalatine fossa are discussed. This minimally invasive approach appears to be a valid alternative for select patients with painful V2 trigeminal neuropathy.

Long-term Follow-up of Patients Treated with Percutaneous Radiofrequency Thermocoagulation via the Foramen Rotundum for Isolated Maxillary Nerve Idiopathic Trigeminal Neuralgia.

OBJECTIVE: The purpose of this study is to evaluate the effectiveness and safety of percutaneous radiofrequency thermocoagulation (PRT) via the foramen rotundum (FR) for the treatment of isolated maxillary (V2) idiopathic trigeminal neuralgia (ITN) and assess the appropriate puncture angle through the anterior coronoid process to reach the FR. METHODS: Between January 2011 and October 2016, 87 patients with V2 ITN refractory to conservative treatment were treated by computed tomography (CT)-guided PRT via the FR at our institution. The outcome of pain relief was assessed by the visual analog scale (VAS) and Barrow Neurological Institute (BNI) pain grade and grouped as complete pain relief (BNI grades I-III) or unsuccessful pain relief (BNI grades IV-V). Recurrence and complications were also monitored and recorded. The puncture angle for this novel approach was assessed based on intraoperative CT images. RESULTS: Of the 87 treated patients, 85 (97.7%) achieved complete pain relief, and two patients (2.3%) experienced unsuccessful pain relief immediately after operation. During the mean follow-up period of 44.3 months, 15 patients (17.2%) experienced recurring pain. No severe complications occurred, except for hypoesthesia restricted to the V2 distribution in all patients (100%) and facial hematoma in 10 patients (11.5%). The mean puncture angle to reach the FR was 33.6° ± 5.7° toward the sagittal plane. DISCUSSION: CT-guided PRT via the FR for refractory isolated V2 ITN is effective and safe and could be a rational therapy for patients with V2 ITN.

Endoscopic Endonasal Transrotundum Middle Fossa Exposure: Technique of Transpterygoid Maxillary Nerve Transposition.

OBJECTIVE: Middle fossa floor access can be challenging. Open skull base approaches have associated morbidity and yield suboptimal working angles around the temporal lobe. Endoscopic endonasal approaches to the middle fossa are poorly described, but provide an improved angle. I hypothesized that the length of the maxillary nerve can be transposed out of the foramen rotundum to provide a path to expose the full width of the middle fossa floor through the anterolateral and anteromedial triangle. METHODS: Endoscopic endonasal transpterygoid dissections to expose the middle fossa were performed bilaterally on 2 silicone-injected cadaveric heads (4 sides). Transposition of V2 was then performed on all sides, and additional middle fossa exposure was achieved. High-resolution computed tomography imaging was obtained to quantify the extent of exposure. A transzygomatic approach was also performed for comparison. RESULTS: The maxillary nerve was successfully transposed in each dissection. A periosteal fold was identified to assist in the mobilization of the infraorbital nerve. The average middle fossa exposure achieved without transposition was 50% (of the medial to lateral width). Transposition increased that to 95%. Comparison with the open transzygomatic approach demonstrated superior surgical trajectory (inferior to superior) with the endonasal route. CONCLUSIONS: Endoscopic endonasal transpterygoid approaches with or without transposition of the maxillary nerve provide a reasonable option for sequentially exposing the entire medial to lateral extent of the anterolateral triangle. It provides an advantageous inferior to superior surgical angle and can be considered for treatment of select middle fossa floor pathology.

A Cadaver Study to Assess the Feasibility of a Cross-Nerve Transfer of the Infraorbital Nerve for Patients With Peripheral Infraorbital Nerve Injury.

BACKGROUND: Patients with facial fracture or head and neck surgery sometimes suffer from infraorbital nerve injury. This injury results in severe hemilateral numbness in the midfacial area. The infraorbital nerve ends with two major branches; the infra nasal branch (INB) and superior labial branch (SLB). In this study, we assessed the feasibility of cross-nerve transfer of the INB and SLB based on a cadaver study. METHODS: The INB/SLB from a total 20 sides of 10 cadavers (2 men and 8 women; average age, 79.9 years) were dissected. The distribution patterns of the INB and SLB, the distance between the INB/SLB and the piriform aperture, and the shortest distance between the INB/SLB were estimated. RESULTS: Three distribution patterns of the INB and SLB were observed, that is type A (65%); only the INB is thick enough for a nerve transfer, type B (20%); only the SLB is thick enough for a nerve transfer, and a combination of types A and B (15%). The distance between the INB, SLB and the piriform aperture was on average 8.61 and 10.81 mm in each. The shortest distance between the INB and SLB was on average 11.34 ± 3.7 mm. CONCLUSIONS: The INB and SLB existed in all the specimens and could be found approximately 1 cm below the piriform aperture. The average distance between the INB and SLB was approximately 11 mm. These results imply the feasibility of a cross-nerve transfer of the distal part of the infraorbital nerve.

Endoscopic Endonasal Interdural Middle Fossa Approach to the Maxillary Nerve: Anatomic Considerations and Surgical Relevance.

BACKGROUND: The maxillary nerve (V2) can be approached via the open middle fossa approach. OBJECTIVE: To delineate the anatomy of V2 and its specific segments with respect to the endonasal landmarks. We present the endoscopic endonasal interdural middle fossa approach to V2 and its potential application for the treatment of perineural spread in sinonasal/skull base tumors. METHODS: Five human head silicon-injected specimens underwent bilateral endoscopic endonasal transpterygoid approaches. V2 prominence and the maxillary strut were identified in the lateral recess along with paraclival carotid protruberance. The regions superior and inferior to V2 corresponding to the anteromedial and anterolateral triangles of the middle fossa were exposed. RESULTS: V2 can be classified into 3 segments: interdural (from the Gasserian ganglion to the proximal part of the maxillary strut), intracanalicular (corresponding to the anteroposterior length of the maxillary strut), and pterygopalatine (distal to the maxillary strut and the site of its divisions). Endonasally, the average length of the interdural and the intracanalicular segments were approximately 9 and 4.4 mm, respectively. V2, following its division distal to the maxillary strut, was successfully dissected off the middle fossa dura and transected just distal to the Gasserian ganglion. CONCLUSION: Endonasally, the interdural segment can be safely mobilized between the periosteal and meningeal dural layers while ensuring the integrity of the middle fossa dura. This allows transection of infiltrated V2 to facilitate tumor resection without entering the intradural/arachnoidal space. Posteriorly, this is limited by the Gasserian ganglion and superomedially by the dural envelope surrounding the cavernous sinus and the paraclival carotid artery.

[Maxillary trigeminal schwannoma. Presentation of a case and review of literature]. / Schwannoma trigeminal maxilar. Presentación de un caso y revisión de la literatura.

INTRODUCTION: Schwannomas are benign tumours that are relatively common in the head, however the involvement of the sinunasal region is rare and there are only 5 cases reported in the maxilla in current literature, representing less than 1% of bone tumours. CLINICAL CASE: We report the case of a woman with a right maxillary schwannoma who underwent a complete resection of the lesion. Emphasis is placed on the rarity of the lesion in terms of its location and includes a review of clinical behaviour, diagnosis and current treatment options. CONCLUSIONS: Maxillary trigeminal schwannoma must be suspected if vague sinunasal symptoms, paranasal mass or, as in this case, trigeminal neuralgia present. Surgical treatment is indicated, and approaches vary according to location and tumour size.

Infraorbital nerve transposition to expand the endoscopic transnasal maxillectomy.

BACKGROUND: The infraorbital nerve (ION) is a terminal branch of the maxillary nerve (V2) providing sensory innervation to the malar skin. It is sometimes necessary to sacrifice the ION and its branches to obtain adequate maxillary sinus exposure for radical resection of sinonasal tumors. Consequently, patients suffer temporary or permanent paresthesia, hypoestesthia, and neuralgia of the face. We describe an innovative technique used for preservation of the ION while removing the anterior, superior, and lateral walls of the maxillary sinus through a medial endoscopic transnasal maxillectomy. METHODS: All patients who underwent transnasal endoscopic maxillectomy with ION transposition in our institute were retrospectively reviewed. RESULTS: Two patients were identified who had been treated for sinonasal cancers using this approach. No major complications were observed. Transient loss of ION function was observed with complete recovery of skin sensory perception within 6 months of surgery. One patient referred to a mild permanent anesthesia of the upper incisors. No diplopia or enophthalmos were encountered in any of the patients. CONCLUSION: The ION transposition is useful for selected cases of benign and malignant sinonasal tumors that do not infiltrate the ION itself but involve the surrounding portion of the maxillary sinus. Anatomic preservation of the ION seems to be beneficial to the postoperative quality of life of such patients.

Transantral endoscopic approach for the treatment of lesions affecting the maxillary nerve.

BACKGROUND: Surgical approaches to skull base lesions that affect the maxillary nerve are complex, due to deep location and presence of relevant neurovascular structures surrounding this area. METHOD: We propose the transantral endoscopic approach (TEA) for the treatment of lesions affecting the maxillary nerve or its vicinity. More specifically, the ones that are located anterior to the foramen rotundum. CONCLUSIONS: This technique represents a minimally invasive treatment option for these kind of cranial base lesions. It offers optimal visualisation similar to the endonasal approach, whereas less dissection is required.

A Novel Surgical Approach to Chronic Temporal Headaches.

The targets for the surgical treatment of temporal headaches are the zygomaticotemporal branch of the trigeminal nerve and the auriculotemporal nerve. The former is often accessed by means of an endoscopic brow approach or potentially by laterally extending a transpalpebral incision. An established surgical approach, the Gillies incision, was modified to access the zygomaticotemporal nerve, as it was felt to combine the advantages of the traditional techniques. Nineteen patients underwent zygomaticotemporal nerve decompression and neuroplasty or neurectomy and muscle implantation using this surgical approach. A 3.5-cm incision was made behind the anterior, temporal hairline and the zygomaticotemporal branch of the trigeminal nerve was approached directly, remaining superficial to the deep temporal fascia. Each patient was assessed preoperatively and postoperatively with regard to the frequency, duration, and severity of their symptoms to calculate a Migraine Headache Index score. All evaluations were performed at least 1 year postoperatively. The mean preoperative Migraine Headache Index score was 131.7 and the mean postoperative score was 52 (p < 0.0001). There were no surgical complications. There appeared to be no differences between those patients that had decompression and neuroplasty versus those that underwent neurectomy and implantation, as both groups experienced significant reductions in Migraine Headache Index scores following the procedure. The anterior temporal approach to the zygomaticotemporal nerve is both safe and effective. The advantages of this approach include a hidden scar, the ability to directly manipulate the nerve for transection or preservation, and access to the auriculotemporal nerve through the same incision.

3D Image-Guided Percutaneous Radiofrequency Thermocoagulation of the Maxillary Branch of the Trigeminal Nerve Through Foramen Rotundum for the Treatment of Trigeminal Neuralgia.

Percutaneous radiofrequency thermocoagulation of the trigeminal ganglion through the foramen ovale is a well-established procedure for the treatment of trigeminal neuralgia (TN). However, this approach can be tricky when individual trigeminal sub-branch nerve block is required. We report our initial experience of image-guided radiofrequency thermocoagulation of the maxillary branch through the use of foramen rotundum.From February 2012 to February 2015, we treated 25 patients with isolated TN of the maxillary branch. Radiofrequency thermocoagulation of the maxillary branch through the foramen rotundum was performed under fluoroscopy. TN pain was evaluated using the visual analogue scale both before and after the procedure.The mean preoperative visual analogue scale score was 8.6 ±â€Š0.8. The pain completely disappeared after the initial procedure in 22 patients and after a second procedure in 2 patients. An additional patient had a postoperative visual analogue scale score of 2 and did not undergo further treatment. Facial numbness occurred in 23 patients but was tolerable. Patients were followed up for a mean of 14.74 months (range, 1-29 months). Recurrence was observed in 9 patients (36%) during the follow-up period. All recurrences were well managed with repeat procedures.Percutaneous radiofrequency thermocoagulation of the maxillary branch through the foramen rotundum under fluoroscopy is a safe and effective procedure for the treatment of isolated TN of the maxillary branch.

[A case report of endoscopic assisted unilateral infraorbital nerve decompression].

Patients of infraorbital nerve injury often appear in the sensory abnormalities of corresponding position, such as numbness or pain. We present a case with numbness of the left cheek because of the injury. The patient were treated by endoscopic assisted on the left infraorbital nerve decompression through the approach of the canine fossa. The symptom shows improvement after the operation. The patient feels numbness significantly ease on 4 months after the operation.

Trigeminal Neuralgia: Evaluation of the Relationship Between the Region of Neuralgic Manifestation and the Site of Neurovascular Compression Under Endoscopy.

This study aimed to evaluate the relationship among the pain region, branches of trigeminal nerve, and the neurovascular compression (NVC) location. A total of 123 consecutive patients with trigeminal neuralgia (TN) underwent endoscope-assisted microvascular decompression according to positive preoperative tomographic angiography. V2 alone was in 51 cases and V3 alone was in 64 cases. The location of NVC was classified into cranial, caudal, medial, or lateral sites. Some patients with multiple regions were recorded as medial + cranial, lateral + cranial, medial + caudal, and lateral + caudal. Twenty-eight (71.8%) of 39 patients with TN (V2) had their NVC at the medial site of the nerve. Twenty-seven (64.3%) of 42 patients with TN (V3) had their NVC at the lateral site of the nerve. There was a statistically significant difference (P = 0.0011 < 0.01, χ2 test). Sixteen (69.6%) of 23 patients with TN(V2) had their NVC at the cranial site of the nerve. Thirty-four (69.4%) of 49 patients with TN (V3) had their NVC at the caudal site of the nerve. There was no statistical difference (P = 0.3097 > 0.01). Evaluation of the relationship between the pain region and the NVC location by endoscopic images during microvascular decompression is more accurate. The second branch is mostly distributed in the medial area, and third branch is mainly distributed in the lateral area.

Surgical management of vasomotor rhinitis: a systematic review.

BACKGROUND: Vasomotor rhinitis (VMR) is one of the most prevalent forms of nonallergic rhinitis. In the past, when maximal medical therapy failed, surgical options were limited. Vidian neurectomy (VN) was one option; however, it was fraught with complications and limited success. The advent of endoscopic sinus surgery revitalized interest in surgical procedures for VMR. This study was designed to review the available literature and assess the safety and efficacy of surgery on the vidian and posterior nasal nerves for treatment of VMR and when possible, compare the different approaches to one another in regard to safety and efficacy. METHODS: A systematic review was performed of English language articles using Ovid and PubMed. Search terms included "endoscopic vidian neurectomy," "vidian neurectomy," "endoscopic posterior nasal neurectomy" (EPNN), and "posterior nasal neurectomy." Only clinical trials performed on humans with safety and or efficacy data were included. Independent extraction of articles by two authors using predefined data fields was performed. Safety defined by complication rates and efficacy defined as objective improvement on outcomes scores along with the overall length of benefit were the primary measures of treatment effect. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement for reporting systematic reviews was followed. RESULTS: In comparison with open VN, endoscopic techniques were not associated with any long-term sequelae. Rhinorrhea and nasal obstruction were shown to improve after endoscopic VN (EVN) and the benefits were maintained for several years after surgery. CONCLUSION: EVN is well tolerated, safe, and effective in a majority of patients. Overall, the literature has shown that the endoscopic approach is associated with less morbidity than the traditional transantral approach. Currently, no literature exists on the effect of EPNN in patients with vasomotor rhinitis and further study is needed to elucidate the efficacy of this procedure in this subset of patients.

Posttraumatic Midface Pain: Clinical Significance of the Anterior Superior Alveolar Nerve and Canalis Sinuosus.

BACKGROUND: Posttraumatic midface pain secondary to injury of the anterior superior alveolar nerve (ASAN) is characterized as pain localized to the central and lateral incisors, canines, and maxilla. This nerve is susceptible to injury and subsequent formation of neuromas after midface trauma. Surgical intervention requires an accurate and precise understanding of the course of the ASAN. METHODS: Dissections of 12 human cadaver heads were conducted to identify the course of the ASAN through the canalis sinuosus (CS). Fifty 1-mm slice face computed tomographic scans were evaluated to document the dimensions and course of the CS. RESULTS: The ASAN branched laterally from the infraorbital nerve before reaching the infraorbital rim in all cadavers. The bifurcation occurred 18 mm posterior to the infraorbital rim (range, 10-30 mm). At a point 25 mm inferior to the infraorbital rim, the ASAN is found 3.4 mm lateral to the piriform aperture (range, 3-4 mm). Radiographic analysis demonstrated a 12.9-mm horizontal length of the CS across the anterior maxilla (SD, 2.2 mm), a distance of 4.8 mm between the piriform aperture and the CS (SD, 1.2 mm), and 11.7 mm vertical length of the CS along the piriform aperture (SD, 3.0 mm). CONCLUSIONS: The ASAN maintains consistent coordinates at specific points along its course through the midface. An improved understanding of the course of the ASAN will guide future diagnosis of injury to this nerve and surgical intervention for patients with posttraumatic midface pain secondary to ASAN injury.