Endoscopic endonasal approaches to infratemporal fossa tumors: a classification system and case series.

OBJECTIVES/HYPOTHESIS: To propose a clinically applicable anatomic classification system describing three progressive endoscopic endonasal approaches (EEAs) to the infratemporal fossa (ITF) and their potential sequelae. Overall feasibility and outcomes of these approaches are presented through a consecutive case series. STUDY DESIGN: Description of classification system for EEAs to the ITF and case series. METHODS: A classification system of EEAs to ITF tumors was created based on the senior author's clinical experience and cadaveric dissection. A retrospective chart review of 21 child and adult patients with primary ITF tumors treated by these approaches from 2008 to 2012 at a tertiary-care academic medical center was conducted. RESULTS: Three progressive EEAs to ITF tumors were defined: 1) a transpterygopalatine fossa approach, 2) a transmedial pterygoid plate approach, and 3) a translateral pterygoid plate approach. Twenty-one patients treated with these approaches were identified consecutively, with a mean age of 44.2 years (range, 11-79 years). Tumors primarily involving the pterygopalatine fossa and not the ITF were excluded. Pathology included three advanced juvenile nasopharyngeal angiofibromas, three adenoid cystic carcinomas, two recurrent inverted papillomas, two trigeminal schwannomas, and 11 other diverse skull base pathologies. No intraoperative or postoperative complications occurred, with a mean follow-up of 21.5 months (range, 1-55 months). Expected potential sequelae such as V2/palatal numbness, Eustachian tube dysfunction, and trismus occurred in 10/21 patients. CONCLUSIONS: EEAs to ITF tumors are technically feasible with low risk of complications for well-selected patients. The proposed classification system is useful for anticipating potential sequelae for each approach.

Reducing nasal morbidity after skull base reconstruction with the nasoseptal flap: free middle turbinate mucosal grafts.

OBJECTIVES/HYPOTHESIS: The nasoseptal flap provides hearty vascularized tissue for reconstruction of expanded endonasal approaches (EEA); however, it produces donor site morbidity due to exposed cartilage. Mucosalization of the septum requires 12 weeks, multiple debridements, and frequent saline rinses. This study addresses the reduction of nasal morbidity by grafting middle turbinate mucosa onto the exposed septum. STUDY DESIGN: Small prospective study with retrospective analysis of a larger cohort. METHODS: Fifteen patients undergoing EEA of the ventral skull base were prospectively enrolled. In seven cases, the sacrificed middle turbinate mucosa was harvested and placed as a free mucosal graft on the septal cartilage. In eight controls, middle turbinate grafting was not performed due to tumor involvement. Septal mucosalization and crusting of all patients was quantified at follow-up appointments. An additional 46 patients were retrospectively identified who received middle turbinate grating on their exposed septal cartilage, and mucosalization rates were determined from clinical records. RESULTS: Three weeks after initial operation, the mucosalization rate was 70% versus 5% in the graft and nongraft groups, respectively. At postoperative week 6, the mucosalization and crusting were 97% and 5% for the graft group versus 60% and 85% for the nongraft group. Mucosalization rates in the retrospective graft series agreed with the prospective series. CONCLUSIONS: Despite donor site morbidity, the nasoseptal flap is becoming the standard of care for skull base reconstruction due to its reliability in reestablishing a barrier between the subarachnoid space and the sinonasal tract. It is possible to dramatically increase the rate of septal mucosalization and decrease crusting by using a middle turbinate free mucosal graft.

A controlled laboratory and clinical evaluation of a three-dimensional endoscope for endonasal sinus and skull base surgery.

BACKGROUND: One criticism of current video systems for endoscopic surgery is that two-dimensional (2D) images lack depth perception and may impair surgical dissection. To objectively measure the efficacy of 3D endoscopy, we designed a training model with specific tasks to show potential differences between 2D and 3D endoscopy. Its clinical value was then evaluated during endoscopic sinus and skull base surgical cases. METHODS: Fifteen subjects were grouped according to endoscopic experience: novices and nonnovices. A training model was constructed to include five tasks: incision manipulation; ring transfer; nerve hook; distance estimation, visual only; and distance estimation, visual and tactile. Each participant was assessed with both a standard 2D endoscope and a 3D endoscope. The clinical value of a 3D endoscope (Visionsense, Ltd., Petach Tikva, Israel) was then examined in four endoscopic sinus cases and four skull base cases. RESULTS: Of the subjects, six (40%) were novices. Overall, the errors committed during any one task were not significantly different between systems. Novices trended toward more success during the nerve hook task using the 3D system. With size cueing versus visualization alone, distance estimation was significantly more accurate. Novices tended to prefer the 3D system and experienced surgeons disliked the initial learning curve. Advantages were particularly noticed during skull base surgery; subjectively improved depth perception was beneficial during vascular dissection. CONCLUSION: Three-dimensional endoscopy may improve depth perception and performance for novices. The 3D endoscope is a safe and feasible tool for endoscopic sinus and skull base surgery; it is promising for improving microneurosurgical dissection precision transnasally.

Nasoseptal "rescue" flap: a novel modification of the nasoseptal flap technique for pituitary surgery.

OBJECTIVES: The introduction of the pedicled nasoseptal flap (NSF) has decreased postoperative cerebrospinal fluid (CSF) leak rates from >20% to <5% during expanded endoscopic skull base surgery. The NSF must be raised at the beginning of the operation to protect the posterior pedicle during the expanded sphenoidotomy. However, in most pituitary tumor cases, an intraoperative CSF leak is not expected but at times encountered. In these cases, a "rescue" flap approach can be used, which consists of partially harvesting the most superior and posterior aspect of the flap to protect its pedicle and provide access to the sphenoid face during the approach. The rescue flap can be fully harvested at the end of the case if the resultant defect is larger than expected, or if an unexpected CSF leak develops. This technique minimized septum donor site morbidity for those patients without intraoperative CSF leaks. RESULTS: The rescue flap technique allows for binaural and bimanual access to the sella without compromise of the pedicle during the extended sphenoidotomies and tumor removal. If an intraoperative CSF leak is encountered, the rescue flap is then converted into a normal nasoseptal flap for skull base reconstruction. If no leak is obtained, then the patient does not suffer additional donor site morbidity from the full flap harvest. CONCLUSIONS: This new technique allows for sellar tumor removal prior to the nasoseptal harvest, thereby eliminating donor site morbidity for those pituitary tumor patients who do not have an intraoperative CSF leak.

Nasoseptal flap takedown and reuse in revision endoscopic skull base reconstruction.

OBJECTIVES/HYPOTHESIS: To provide a description of the techniques and limitations of nasoseptal flap takedown and reuse during second-stage and revision endoscopic skull base surgery and review the institutional experience with the use of this reconstructive technique. STUDY DESIGN: : Case series. METHODS: A retrospective analysis of cerebrospinal fluid (CSF) leak outcomes was performed for a consecutive series of patients who underwent the nasoseptal flap takedown technique during endoscopic skull base surgery at two tertiary care skull base centers. RESULTS: Twenty-eight consecutive cases with nasoseptal flap takedown procedures for endoscopic skull base reconstruction were collected and evaluated for flap viability and CSF leak outcomes. This cohort was composed of 14 revision surgeries and 14 planned second-stage procedures. There were no cases of flap loss. Twenty cases involved the presence of intraoperative CSF leaks. Twelve of these 20 cases were second-stage surgeries, and eight were revision or recurrent-tumor procedures. Nineteen of 20 had successful skull base reconstruction without a postoperative CSF leak. One patient required revision endoscopic CSF leak repair and bolstering of the defect with a fat graft 3 days after the initial surgery. Endoscopic skull base reconstructive techniques and limitations of flap takedowns are discussed. CONCLUSIONS: Expansion of the limits of endoscopic skull base surgery must be accompanied by the development of new reconstructive options. This report illustrates the ability to take down and reuse the nasoseptal flap in staged and revision cases with a high success rate and minimal additional nasal morbidity.

A prospective study of the clinical impact of a multidisciplinary head and neck tumor board.

OBJECTIVE: There have been no studies undertaken on the effect of the multidisciplinary head and neck tumor board on treatment planning. The objective of this study was to determine the efficacy of the multidisciplinary tumor board in altering diagnosis, stage, and treatment plan in patients with head and neck tumors. STUDY DESIGN: Case series with planned data collection. SETTING: Comprehensive cancer center and tertiary academic hospital. SUBJECTS AND METHODS: A prospective study of the discussions concerning 120 consecutive patients presented at a multidisciplinary head and neck tumor board was performed. As each patient was presented, a record was made of the "pre-conference" diagnosis, stage, and treatment plan. After case discussion, the "post-conference" diagnosis, stage, and treatment plan were recorded. Results are compared between malignant and benign tumor cohorts. RESULTS: The study population comprised 120 patients with new presentations of head and neck tumors: 84 malignancies and 36 benign tumors. Approximately 27 percent of patients had some change in tumor diagnosis, stage, or treatment plan. Change in treatment was significantly more common in cases of malignancy, occurring in 24 percent of patients versus six percent of benign tumors (P = 0.0199). Changes in treatment were also noted to be largely escalations in management (P = 0.0084), adding multi-modality care. CONCLUSION: A multidisciplinary tumor board affects diagnostic and treatment decisions in a significant number of patients with newly diagnosed head and neck tumors. The multidisciplinary approach to patient care may be particularly effective in managing malignant tumors, in which treatment plans are most frequently altered.

Anatomical considerations for endoscopic endonasal skull base surgery in pediatric patients.

OBJECTIVES/HYPOTHESIS: Pediatric skull base surgery is limited by several boney sinonasal landmarks that must be overcome prior to tumor dissection. When approaching a sellar or parasellar tumor, the piriform aperture, sphenoid sinus pneumatization, and intercarotid distances are areas of potential limitation. Quantitative pediatric anatomical measurements relevant to skull base approaches are lacking. Our goal was to use radio-anatomic analysis of computed tomography scans to determine anatomical limitations for trans-sphenoidal approaches in pediatric skull base surgery. STUDY DESIGN: A radio-anatomic cross-sectional survey. METHODS: Measurements included the diameter of the piriform aperture, posterior extent of sphenoid sinus pneumatization, and intercarotid distances on fine-cut, age-stratified maxillofacial scans. Fifty pediatric (<18 years of age) and 10 adult patients were equally subdivided into seven age groups and compared to determine age-related differences in sphenoid sinus pneumatization, skull base thicknesses, and intercarotid distances. RESULTS: Piriform aperture width was significantly greater in adults than in patients under age 7 years (P

Transpalatal greater palatine canal injection: Radioanatomic analysis of where to bend the needle for pediatric sinus surgery.

BACKGROUND: The greater palatine canal (GPC) local injection is used to limit posterior bleeding during sinus surgery in adults. Given the potential for causing iatrogenic damage to the intraorbital contents, this procedure is not commonly used in the pediatric population. No studies have described the anatomic development of the GPC during facial growth. By using age-stratified radioanatomic analysis, the dimensions of the GPC and the clinical implications are described for pediatric patients. An age-stratified radioanatomic study was performed. METHODS: High-resolution computed tomography measurements included the thickness of the mucosal plane overlying the GPC, the length of the GPC, and the distance between the base of the pterygopalatine fossa (PPF) and the orbital floor. Mean distance and standard deviation were calculated for each age cohort and compared using the one-way ANOVA test. RESULTS: The GPC length correlated directly with patient age. It varied from 9.14 ± 0.11 mm in the youngest age group (<2 years) to 19.36 ± 2.76 mm in adults (18-64 years). The height of the orbit relative to the hard palate approximated the adult dimensions described in the literature by 12-13 years (49.58 ± 1.72 mm). CONCLUSION: These radioanatomic results suggest that the GPC injection described for adult patients may be safely administered to selected pediatric patients. For patients >12 years old, we recommend bending the needle 45° and inserting it 25 mm. For patients 6-12 years old, the needle should be inserted 20 mm to enter into the PPF. In patients <6 years old, the needle may safely be placed 12 mm into the GPC. Each of these descriptions is based on the minimal distance required to effectively access the PPF but with maximal safety in regard to the orbit. Further clinical correlation of these findings is necessary through future investigation.

Post-transplantation lymphoproliferative disease: Epstein-Barr virus DNA levels, HLA-A3, and survival.

RATIONALE: Elevation in Epstein-Barr virus (EBV) circulating DNA has been proposed as a marker for development of post-transplant lymphoproliferative disease (PTLD), but few published data exist in the study of lung-transplant recipients. OBJECTIVES: To determine if elevated EBV DNA levels, in combination with other risk factors, were predictive of PTLD. METHODS: We conducted a retrospective, single-center study examining all lung transplant recipients (n = 296) and EBV DNA levels (n = 612) using real-time TaqMan polymerase chain reaction. There were 13 cases of PTLD overall, of which 5 occurred in the era of EBV DNA monitoring. MEASUREMENTS AND MAIN RESULTS: EBV DNA levels were distributed differently among seropositive and seronegative patients, with the latter having higher values (P < 0.0001). Among the cohort of pretransplantation seropositive patients, there was one diagnosed with PTLD. The EBV DNA level in this patient was elevated at the time of PTLD diagnosis (sensitivity = 100%, specificity = 100% for PTLD). Among the cohort of pretransplantation seronegative patients, there were four with a diagnosis of PTLD. In all four patients, the EBV DNA level was detectable (sensitivity = 100%, specificity = 24%), but in only two was it elevated (sensitivity = 50%, specificity = 22%). HLA-A3 expression in the recipient and/or donor conferred additional risk for PTLD among the seronegative patients (P = 0.026 to 0.003). No other PTLD risk factor was found. CONCLUSIONS: EBV DNA levels are a useful but imperfect predictor of PTLD in patients with lung transplants. Pretransplant EBV status affected the results of the assay and should be considered when interpreting test results. HLA-A3 was strongly linked to PTLD and may be a novel marker of PTLD risk.