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.

Medial and Superior Orbital Decompression: Improving Access for Endonasal Endoscopic Frontal Sinus Surgery.

OBJECTIVE: Visualization by Draf I-III endoscopic access to the frontal sinus via drainage pathways is sometimes inadequate. We compare lateral frontal sinus exposures by Draf approaches versus our modification of removing the medial-superior wall of the orbit while preserving the periorbita. METHODS: Twenty cadaveric heads dissected using Draf IIB, III, and modified Draf III with medial and superior orbital decompression (MSOD) underwent thin-cut computed tomography (CT) scanning. Under image guidance, measurements extended from the midline crista gali to the most lateral point of the frontal sinus. A case report shows the modified Draf III improved frontal sinus access. RESULTS: Comparing Draf IIB and III with Draf III with MSOD, respectively, distances between midline and most lateral point averaged 19.1 mm, 23.7 mm, and 30.4 mm (left) and 18.7 mm, 25.1 mm, and 32.2 mm (right). Differences between Draf III with/without MSOD were 6.65 mm (left) and 7.09 mm (right); 12 heads were excluded because of under-pneumatization of the sinuses. CONCLUSIONS: Draf III with MSOD extended surgical access to lateral regions of the frontal sinus. This extension achieved better visualization and instrumentation with minimal removal of the frontal bone's orbital segment anterior and superior to the anterior ethmoidal artery while preserving the periorbita.

Long-Term Results of Endoscopic Endonasal Marsupialization of Rathke Cleft Cysts With Bioabsorbable Steroid-Eluting Stents-Technical Case Series and Review of the Literature.

BACKGROUND: Rathke cleft cysts (RCCs) are common benign skull-base lesions arising from embryologic remnants of Rathke pouch. Though frequently asymptomatic, RCCs can become symptomatic because of compression of adjacent neural structures. Transcranial and neuroendoscopic surgical treatments have been described for symptomatic RCCs, but recurrence rates remain as high as 30%. Bioabsorbable steroid-eluting (BASE) stents significantly decrease adhesions and recurrent ostia obstruction after endoscopic sinus surgery. We sought to use BASE stents to aid marsupialization of symptomatic RCCs. OBJECTIVE: To present long-term results of our initial experience with endoscopic-endonasal fenestration and placement of BASE stents for RCCs. METHODS: Patients undergoing neuroendoscopic transsphenoidal fenestration of RCCs with BASE stent placement were identified and their medical records retrospectively reviewed. RESULTS: Four patients underwent neuroendoscopic transsphenoidal fenestration and BASE stent placement from March 2016 to April 2018 for symptomatic RCCs. After the cyst contents were evacuated, a BASE stent was deployed in the cyst fenestration to prevent cyst wall regrowth or closure and facilitate marsupialization to the sphenoid sinus. No perioperative complications were encountered, and all patients reported symptom resolution by 2 weeks postoperatively. Postoperative endoscopic evaluation demonstrated epithelization of the cyst wall opening and patent marsupialization into the sphenoid sinus in all cases. After a mean follow-up of 56 ± 12 months, all patients remained asymptomatic with baseline visual function and no radiographic evidence of recurrence. CONCLUSION: Bioabsorbable steroid-eluting stent placement is a safe, facile, viable augmentation of neuroendoscopic technique for symptomatic RCCs with the potential to reduce long-term recurrence rates.

Anatomic study of the prechiasmatic sulcus and its surgical implications.

To address a lack of anatomical descriptions in the literature regarding the prechiasmatic sulcus, we conducted an anatomical study of this sulcal region and discuss its clinical relevance to cranial base surgery. Our systematic morphometric analysis includes the variable types of chiasmatic sulcus and a classification schema that has surgical implications. We examined the sulcal region in 100 dry skulls; bony relationships measured included the interoptic distance, sulcal length/width, planum sphenoidale length, and sulcal angle. The varied anatomy of the prechiasmatic sulcii was classified as four types in combinations of wide to narrow, steep to flat. Its anterior border is the limbus sphenoidale at the posterior aspect of the planum sphenoidale. The sulcus extends posteriorly to the tuberculum sellae and laterally to the posteromedial aspect of each optic strut. Averages included an interoptic distance (19.3 +/- 2.4 mm), sulcal length (7.45 +/- 1.27 mm), planum sphenoidale length (19 +/- 2.35 mm), and sulcal angle (31 +/- 14.2 degrees). Eighteen percent of skulls had a chiasmatic ridge, a bony projection over the chiasmatic sulcus. The four types of prechiasmatic sulcus in our classification hold potential surgical relevance. Near the chiasmatic ridge, meningiomas may be hidden from the surgeon's view during a subfrontal or pterional approach. Preoperative evaluation by thin-cut CT scans of this region can help detect this ridge.

Extended Anterior Petrosectomy Through the Transcranial Middle Fossa Approach and Extended Endoscopic Transsphenoidal-Transclival Approach: Qualitative and Quantitative Anatomic Analysis.

BACKGROUND: Petroclival tumors and ventrolateral lesions of the pons present unique surgical challenges. This cadaveric study provides qualitative and quantitative anatomic comparison for an anterior petrous apicectomy through the transcranial middle fossa (TMF) and expanded endoscopic transsphenoidal-transclival approaches. METHODS: In 10 silicone-injected heads, the petrous apex and clivus were drilled extradurally using middle fossa and endonasal approaches. With in situ and frameless stereotactic navigation, we defined consistent points to compare working areas, bone removal volumes, approach angles, and surgical freedom. RESULTS: Mean exposed TMF area (21.03 ± 3.46 cm2) achieved a 44.71 ± 4.13° working angle to the brainstem between cranial nerves V and VI. Kawase's rhomboid area measured 1.76 ± 0.34 cm2, and bone removal averaged 1.20 ± 0.12 cm3 at the petrous apex. Surgical freedom on the lateral brainstem was higher halfway between cranial nerves V and VI at the center of the rhomboid compared with midline at the basilar sulcus (P < 0.01). After clivectomy and petrous apicectomy, mean exposed expanded endoscopic transsphenoidal-transclival area was 5.29 ± 0.66 cm2. Approach from either nostril showed no statistically significant differences in surgical freedom at the foramen lacerum and midpoint basilar sulcus. At the petrous apex, bone volume removed and area exposed were significantly larger for the TMF approach (P < 0.001). CONCLUSIONS: Expanded transclival anterior petrosectomy through the TMF approach provides an adequate corridor to lesions in the upper ventrolateral pons. The expanded endoscopic transsphenoidal-transclival approach better fits midline lesions not extending laterally beyond cranial nerve VI and C3 carotid when evaluating normal anatomic parameters.

Anatomy of the optic canal: a computed tomography study of endoscopic nerve decompression.

OBJECTIVES: Endoscopic optic nerve decompression has variable success rates. Our goal was to further delineate the radiographic anatomy of the optic canal to determine whether the variable success can be explained on anatomic principles. METHODS: The optic canal dimensions and the degree of optic canal exposure to the sphenoid sinus were measured on sinus computed tomography images of 96 patients. RESULTS: A total of 191 optic canals were analyzed (111 female subjects and 80 male subjects). The average medial canal wall length was 1.48 cm (range, 0.7 to 2.3 cm). The length in male subjects was 1.61 cm (range, 1.1 to 2.3 cm), as compared to 1.39 cm (range, 0.7 to 2.0 cm) in female subjects (p < 0.001). Onodi cells and pneumatized anterior clinoid processes were present on 14 and 16 images, respectively. The average degree of exposure of the optic canal to the sphenoid sinus in optic canals without Onodi cells or clinoid pneumatization was 99.3 degrees, and in optic canals with both Onodi cells and clinoid pneumatization it was 117.7 degrees. The potential area of canal exposed was 0.66 cm2, or 28% of the total surface area. CONCLUSIONS: A wide variation in medial canal wall length and exposure of the optic canal to the sphenoid sinus exists on computed tomography images. Variation in medial canal wall length and optic canal exposure may limit the surface area of nerve available for endoscopic optic nerve decompression.

Incidence of epistaxis after endoscopic pituitary surgery: Proposed treatment algorithm.

Endoscopic transsphenoidal surgery for pituitary tumors is an increasingly common practice. Little has been reported on the incidence and treatment of postoperative epistaxis in this population. The aim of this study was to analyze the incidence of postoperative epistaxis and formulate a treatment algorithm based on our experience. We performed a case series with chart review. A total of 434 consecutive patients who had endoscopic transsphenoidal pituitary surgery were identified between April 2006 and November 2013. The incidence, clinical management, and outcomes were recorded. Based on the data, a treatment algorithm was constructed. Fifty-two percent of patients treated were female (mean age: 51.4 years). Tumor types included pituitary adenomas (73.3%), Rathke cleft cysts (19.6%), and other pathologies (6.7%). Eighteen patients reported an epistaxis event within 6 weeks of surgery (4.1%). Treatment included office cauterization in 7 (1.6%) patients, a return to the operating room for 5 (1.2%), nasal packing in 3 (0.7%), embolization in 2 (0.5%), and use of intranasal hemostatic agents in 1 (0.2%). Epistaxis after endoscopic pituitary surgery is concerning for rapid blood loss and risk of intracranial complications. Fortunately, in the absence of new cranial nerve palsy, most bleeding can be controlled with conservative measures such as topical cautery, hemostatic agents, and nasal packing. An algorithm is presented to help guide physician decision making in this clinical scenario.

Refining Operative Strategies for Optic Nerve Decompression: A Morphometric Analysis of Transcranial and Endoscopic Endonasal Techniques Using Clinical Parameters.

BACKGROUND: Various approaches can be considered for decompression of the intracanalicular optic nerve. Although clinical experience has been reported, no quantitative study has yet compared the extent of decompression achieved by an endoscopic endonasal versus transcranial approach. OBJECTIVE: Toward this aim, our morphometric analysis compared both approaches by quantifying the circumferential degree of optic canal decompression that is possible before any meningeal violation, which would result in cerebrospinal fluid (CSF) leak. METHODS: From 10 cadaver heads, 20 optic canals were sequentially decompressed using an endoscopic endonasal approach and pterional craniotomy with extradural clinoidectomy. Dissections ended before violation of the sphenoid sinus during the transcranial approach, and before intracranial transgression from the endonasal corridor. Based on our study criteria, decompressions were not maximal for either approach, but were maximal before violating the other compartment. Decompression achieved from each approach was quantified using CT scans for each stage. RESULTS: Greater circumferential bony optic canal decompression was obtained from transcranial (245.2°) than endonasal (114.8°) routes (P < .001). By endonasal perspective, the anatomical point where the optic nerve traverses intracranially was approximated by the medial border of the anterior ascending cavernous internal carotid artery. CONCLUSION: Our morphometric analysis comparing optic canal decompression for endonasal and transcranial corridors provides important guidance for this location. Ample visualization and wide exposure can be achieved via a transcranial approach with limited risk of CSF leak. A landmark, where the intracanalicular segment ends and optic nerve traverses intracranially, can mark the extent of decompression safely obtained before risking CSF leak.

Endoscopic transorbital superior eyelid approach: anatomical study from a neurosurgical perspective.

OBJECTIVERecent studies have proposed the superior eyelid endoscopic transorbital approach as a new minimally invasive route to access orbital lesions, mostly in otolaryngology and maxillofacial surgeries. The authors undertook this anatomical study in order to contribute a neurosurgical perspective, exploring the anterior and middle cranial fossa areas through this purely endoscopic transorbital trajectory.METHODSAnatomical dissections were performed in 10 human cadaveric heads (20 sides) using 0° and 30° endoscopes. A step-by-step description of the superior eyelid transorbital endoscopic route and surgically oriented classification are provided.RESULTSThe authors' cadaveric prosection of this approach defined 3 modular routes that could be combined. Two corridors using bone removal lateral to the superior and inferior orbital fissures exposed the middle and anterior cranial fossa (lateral orbital corridors to the anterior and middle cranial base) to unveil the temporal pole region, lateral wall of the cavernous sinus, middle cranial fossa floor, and frontobasal area (i.e., orbital and recti gyri of the frontal lobe). Combined, these 2 corridors exposed the lateral aspect of the lesser sphenoid wing with the Sylvian region (combined lateral orbital corridor to the anterior and middle cranial fossa, with lesser sphenoid wing removal). The medial corridor, with extension of bone removal medially to the superior and inferior orbital fissure, afforded exposure of the opticocarotid area (medial orbital corridor to the opticocarotid area).CONCLUSIONSAlong with its minimally invasive nature, the superior eyelid transorbital approach allows good visualization and manipulation of anatomical structures mainly located in the anterior and middle cranial fossae (i.e., lateral to the superior and inferior orbital fissures). The visualization and management of the opticocarotid region medial to the superior orbital fissure are more complex. Further studies are needed to prove clinical applications of this relatively novel surgical pathway.

Supraorbital vs Endo-Orbital Routes to the Lateral Skull Base: A Quantitative and Qualitative Anatomic Study.

BACKGROUND: Various extensions of the supraorbital approach reach the lateral and parasellar middle cranial fossa regions by removing the orbital rim and greater/lesser sphenoid wings. Recent proposals of a purely endoscopic ventral transorbital pathway to these regions heighten the need to compare these surgical windows. OBJECTIVE: To detail the lateral and parasellar middle cranial fossa regions and quantify exposures by 2 surgical windows (transcranial and transorbital) through anatomic study. METHODS: In 5 cadaveric specimens (10 sides), dissections consisted of 3 stages: stage 1 began with the supraorbital approach via the eyebrow; stage 2, endo-orbital approach via the superior eyelid, continued with removal of lesser and greater sphenoid wings; and stage 3, extended supraorbital, re-evaluated the gains of stage 2 from the perspective of stage 1. Operative working areas were quantified in Sylvian, anterolateral temporal, and parasellar regions; bone removal volumes were measured at each stage (nonpaired Student t-test). RESULTS: Visualization into the anterolateral temporal and Sylvian areas, though varied in perspective, were comparable with either eyelid or transcranial routes. Compared with transcranial views through a supraorbital window, the eyelid approach significantly increased exposure in the parasellar region with wider angle of attack (P < .01) and achieved comparable bone removal volumes. CONCLUSION: Stage 2's unique anatomic view of the lateral and parasellar middle cranial fossa regions paves the way for possible surgical application to select pathologies typically treated via transcranial approaches. Disadvantages may be the surgeon's unfamiliarity with the anatomy of this purely endoscopic, ventral route and difficulties of dural and orbital repair.

Paratrigeminal, Paraclival, Precavernous, or All of the Above? A Circumferential Anatomical Study of the C3-C4 Transitional Segment of the Internal Carotid Artery.

BACKGROUND: Although the term paraclival carotid pervades recent skull base literature, no clear consensus exists regarding boundaries or anatomical segments. OBJECTIVE: To reconcile various internal carotid artery (ICA) nomenclatures for transcranial and endoscopic-endonasal perspectives, we reexamined the transition between lacerum (C3) and cavernous (C4) segments using a C1-C7 segments schema. In this cadaveric study, we obtained a 360°-circumferential view integrating histological, microsurgical, endoscopic, and neuroradiological analyses of this C3-C4 region and identified a distinct transitional segment. METHODS: In 13 adult, silicone-injected, formalin-fixed cadaveric heads (26 sides), transcranial-extradural-subtemporal and endoscopic-endonasal CT-guided dissections were performed. A quadrilateral area was noted medial to Meckel's cave between cranial nerve VI, anterolateral and posterolateral borders of the lateral-paratrigeminal aspect of the precavernous ICA, and posterior longitudinal ligament. Endoscopically, a medial-paraclival aspect was defined. Anatomical correlations were made with histological and neuroradiological slides. RESULTS: We identified a distinct precavernous C3-C4 transitional segment. In 18 (69%) specimens, venous channels were absent at the quadrilateral area, on the paratrigeminal border of the precavernous ICA. A trigeminal membrane, seen consistently on the superior border of V2, defined the lateral aspect of the cavernous sinus floor. The medial aspect of the precavernous ICA corresponded with the paraclival ICA. CONCLUSION: Our study revealing the juncture of 2 complementary borders of the ICA, endoscopic endonasal (paraclival) and transcranial (paratrigeminal), reconciles various nomenclature. A precavernous segment may clarify controversies about the paraclival ICA and support the concept of a "safe door" for lesions involving Meckel's cave, cavernous sinus, and petrous apex.

Operative Learning Curve After Transition to Endoscopic Transsphenoidal Pituitary Surgery.

BACKGROUND: No clear consensus yet defines the endpoints for operative learning curves in the transition to minimally invasive endoscopic techniques. This retrospective review of our first 202 patients who underwent endoscopic pituitary resection examines the statistical learning curve related to operative times-a measure of our surgical team's efficiency and complication rate, a reflection of surgical skill and maturity. METHODS: Retrospective chart review included patient demographic data, tumor type, operative time, complications, and follow-up. During the 5-year study period, surgeries were performed by an otolaryngology-neurosurgery team. Statistical analysis by Pearson's correlation delineated a learning curve for operative time and complications. RESULTS: Our learning curve showed comparable plateaus: 120 cases (48% males, 52% females) for operative time (mean, 134 minutes; range, 62-307 minutes) and 100 cases for incidence of cerebrospinal fluid (CSF) leak. The risk of CSF leak declined significantly with the surgeon's increasing experience. Complication rates were as follows: temporary nasal obstruction, 9.9%; CSF leak, 8.4%; postoperative epistaxis, 7%; sinusitis, 4.5%; septal osteomyelitis, 2.4%; postoperative sellar hematoma, 1.5%; anosmia, 0.5%; and septal perforation, 0.5%. The overall CSF leak rate included 5.5% intraoperative and 2.9% postoperative; most cases resolved with a lumbar drain. Four patients (2%) underwent postoperative surgical repair and lumbar drainage. CONCLUSION: Our learning curve-defined endpoints for 2 measures, operative time and complication rates, support improved outcomes for reduced CSF leaks, the most common complication, with increasing operative experience. We will continue to examine the implications related to safety, efficacy, and the need for subspecialization in this minimally invasive surgery.

Base of tongue schwannoma: a case report.

Both malignant and benign lesions may be found on the base of the tongue, including metastasis from other sites. Various surgical approaches to the base of tongue have been described. Here, we report a case of a 26-year-old woman with a schwannoma in the base of tongue removed through a suprahyoid pharyngotomy approach. The biology and pathology of schwannoma in the oral cavity are discussed. The advantage of the suprahyoid pharyngotomy approach for complete excision of a mass in the base of tongue is demonstrated.

Resection of a recurrent paraganglioma via an endoscopic transnasal approach to the jugular fossa.

OBJECTIVE: To present a novel endoscopic, transnasal approach to a recurrent paraganglioma of the jugular fossa (glomus jugulare). STUDY DESIGN: Case report and review of the literature. SETTING: The study was carried out at the University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, U.S.A. PATIENT: A 64-year-old woman presented to the University of Pittsburgh Medical Center with a 9-month history of left otalgia, occasional vertigo, facial pain, and recurrent epistaxis. She had undergone two previous procedures over the past 35 years for a glomus tympanicum. Physical examination revealed a mass in the left nasopharynx originating from the eustachian tube. A computed tomographic scan revealed an expansive mass in the left jugular foramen extending into the posterior parapharyngeal space suggestive of a large jugular paraganglioma. INTERVENTION: The patient underwent preoperative embolization of the paraganglioma. An endoscopic, transnasal approach along the eustachian tube, the ascending parapharyngeal carotid artery, and into the jugular fossa was used to remove the tumor. Intraoperative image guidance assisted in the identification of key anatomic landmarks. RESULTS: Postoperative magnetic resonance imaging revealed a thin rim of enhancement at the posterior aspect of the jugular fossa consistent with residual tumor. The patient was discharged to home on postoperative Day 1 in stable condition. There have been no complications with 4 months of follow-up, and the left facial paralysis secondary to preoperative embolization has resolved. CONCLUSION: We report the successful subtotal resection of a recurrent paraganglioma via a novel endoscopic, transnasal, transclival, transpetrous approach with image guidance. This approach allowed the near-total resection of a recurrent glomus jugulare with minimal surgical morbidity. Technological advances and surgical experience with nasal endoscopy and image guidance allow minimally invasive surgical management of select extracranial lesions of the lateral cranial base.

Causes for 30-Day Readmission following Transsphenoidal Surgery.

OBJECTIVE: The Affordable Care Act Readmissions Reduction Program introduced reimbursement policy changes resulting in penalties for hospitals with higher-than-average readmission rates among several categories, including elective surgical cases. We examined the rate of complications resulting in 30-day readmission following endoscopic transsphenoidal surgery. STUDY DESIGN: Case series with chart review. SETTING: Academic tertiary care center. METHODS: A database of 466 consecutive patients who underwent endoscopic transsphenoidal surgery at a tertiary care center between April 2006 and July 2014 was reviewed for 30-day causes for readmission, length of stay, level of care required, and average cost. RESULTS: Twenty-nine readmissions were identified within our study period, indicating a 30-day readmission rate of 6.2%. Among all patients, rates of 30-day readmission were 2.1% for epistaxis, 1.5% for hyponatremia, 0.9% for cerebrospinal fluid leak, and 1.7% for other medical conditions. Average cost per readmission ranged from $6011 for hyponatremia to $24,613 for cerebrospinal fluid leak. CONCLUSION: Overall, the rate of 30-day readmission following endoscopic pituitary surgery is low. However, common causes of readmission do add significant cost to the overall care of this patient population. Special attention to surgical technique to prevent epistaxis and cerebrospinal fluid rhinorrhea, as well as multidisciplinary team management to avoid postoperative endocrine dysfunction, is critical to minimize these complications.

Infundibular Hemangioblastoma in a Patient with Neurofibromatosis Type 1: Case Report and Review of the Literature.

BACKGROUND: Supratentorial hemangioblastomas are rare tumors, most commonly occurring in the sellar/suprasellar region, cerebrum, and ventricle. They are generally found in patients with von Hippel Lindau disease but have infrequently been reported in patients without this syndrome. CASE DESCRIPTION: A 35-year-old woman with a history of neurofibromatosis type 1 presented to our care with visual loss and headaches. Magnetic resonance imaging of the brain demonstrated an 8-mm cystic, contrast-enhancing lesion abutting the optic chiasm and optic tracts. The patient's endocrine profile was unremarkable. The tumor was resected using an endoscopic expanded transsphenoidal approach. Pathologic evaluation was consistent with hemangioblastoma. Postoperatively, the patient experienced an improvement in her visual symptoms. CONCLUSIONS: Hemangioblastoma should be included in the differential of sellar/suprasellar mass lesions, particularly in patients with von Hippel Lindau disease. Small suprasellar lesions may be safely and effectively removed using an expanded transsphenoidal approach.

The Medial Extra-Sellar Corridor to the Cavernous Sinus: Anatomic Description and Clinical Correlation.

OBJECTIVE: The zenith of surgical interest in the cavernous sinus peaked in the 1980s, as evidenced by reports of 10 surgical triangles that could access the contents of the lateral sellar compartment (LSC). However, these transcranial approaches later became marginalized, first by radiosurgery's popularity and lower morbidity, and then by clinical potential of endoscopic corridors noted in several qualitative studies. Our anatomic study, taking a contemporary look at the medial extra-sellar corridor, gives a detailed qualitative-quantitative analysis for its use with increasingly popular endoscopic endonasal approaches to the cavernous sinus. METHODS: In 20 cadaveric specimens, we re-examined the anatomic landmarks of the medial corridor into the LSC with qualitative descriptions and measurements. An illustrative case highlights a recurrent symptomatic pituitary adenoma that invaded the cavernous sinus approached through the medial corridor. RESULTS: The corridor's shape varied from tetrahedron to hexahedron. Comparing right and left sides, width averaged 3.6 ± 4.5 mm and 4.0 ± 4.4 mm, and height averaged 2.3 mm and 2.1 mm, respectively. About 35% of sides showed ample space for access into the cavernous sinus. Our case report of successful outcome lends support for the safety and efficacy of this endoscopic approach. CONCLUSIONS: Our re-examination of this particular surgical access into the LSC refines the understanding of the medial extra-sellar corridor as a main endoscopic access route to this compartment. Achieving safe access to the contents of the LSC, this 11th triangle is clinically relevant and potentially superior for select lesions in this region.

Current use of 18F-fluorodeoxyglucose positron emission tomography and combined positron emission tomography and computed tomography in squamous cell carcinoma of the head and neck.

The history and physical examination, computed tomography (CT) and magnetic resonance imaging are the cornerstones for identifying new and recurrent cancers of the head and neck. The advent of positron emission tomography (PET) and combined PET/CT imaging technology is a promising development. These modalities have the potential to help stage patients presenting with head and neck cancer, identify responses to nonsurgical therapy, and allow earlier detection of recurrence in the hope of improving survival. The following paper provides a brief history of PET and PET/CT imaging. The current PET and PET/CT literature for squamous cell carcinoma of the head and neck is reviewed, and specific recommendations for its use are provided.

The use of combined PET/CT for localizing recurrent head and neck cancer: the Pittsburgh experience.

We performed a retrospective study of 47 patients to ascertain the ability of combined positron-emission tomography and computed tomography (PET/CT) to localize recurrent head and neck cancer. When clinically warranted, biopsies were performed in an attempt to obtain pathologic confirmation of the PET/CT findings. Of the 47 patients, 33 exhibited PET/CT findings consistent with recurrent cancer. Of the 33 patients, 25 underwent either biopsy or surgical excision of disease in an attempt to obtain a pathologic confirmation. Biopsy analysis confirmed the PET/CT findings in 22 of these patients; in the remaining 3 patients, pathologic findings were inconsistent with the PET/CT diagnosis. Based on the subset of 25 patients who underwent pathologic testing, the sensitivity of combined PET/CT was 95% and the specificity was 60%. We conclude that combined PET/CT imaging is a valuable tool for localizing tumor recurrence in patients with head and neck cancer.

Comparing operative exposures of the le fort I osteotomy and the expanded endoscopic endonasal approach to the clivus.

Objectives We compare surgical exposures to the clivus by Le Fort I osteotomy (LFO) and the expanded endoscopic endonasal approach (EEEA). Methods Ten cadaveric specimens were imaged with 1.25-mm computed tomography. After stereotactic navigation, EEEA was performed followed by LFO. Clival measurements included lateral and vertical limits to the midline lower extent of exposure (t test). Results For EEFA and LFO, respectively, maximal lateral exposure in millimeters (mean ± standard deviation) was 24.5 ± 3.7 and 24.5 ± - 3.8 (p = 0.99) at the opticocarotid recess (OCR) and 25.1 ± - 4.1 and 24.1 ± - 3.0 (p = 0.53) at the foramen lacerum level; lateral reach at the hypoglossal canals was 39.0 ± - 5.88 and 56.1 ± - 5.3 (p = 0.0004); and vertical extension was 56.0 ± - 4.1 and 56.3 ± - 3.4 (p = 0.78). Conclusions For clival exposures, LFO and EEEA were similar craniocaudally and laterally at the levels of the OCR and foramen lacerum. LFO achieved greater exposure at the level of the hypoglossal canal.