The utility of cadaver dissection in endoscopic sinus surgery training courses.

BACKGROUND: Understanding paranasal sinus anatomy is crucial for successful outcomes in endoscopic sinus surgery (ESS). This study was designed to evaluate subjective and objective differences in ESS cadaver dissections among participants of varying experience levels in association with the use of image guidance and computer-aided technologies in a physician training cadaver dissection laboratory. METHODS: Participants in a 2-day cadaver dissection course completed daily predissection surveys evaluating subjective comfort with ESS. Pre- and postdissection computer tomography (CT) scans assessed completeness of dissection. Images were analyzed for maxillary antrostomy, frontal and sphenoid sinusotomy, residual ethmoid cells and partitions, and residual frontal recess cells. RESULTS: Fifty-one sides were dissected. Participant comfort increased significantly from day 1 to 2 for overall ESS (p = 0.001) and for individual sinuses (p < 0.001 to p = 0.047). Participants with more years in practice had fewer unopened ethmoid cells (p = 0.015) and frontal recess cells (p = 0.014) on dissection day 1. Participants with increased comfort in ethmoid dissection had fewer retained ethmoid partitions on day 1 (p = 0.017). Observed differences on dissection day 1 for unopened ethmoid and frontal recess cells and retained ethmoid partitions were not present on day 2. No significant differences were found based on use of image guidance for any parameter. CONCLUSION: Surgeons with increased comfort and more years in practice had more complete endoscopic cadaver dissections initially. Differences among participants diminished on dissection day 2, indicating the ability to review postdissection CT scans may improve surgeon comfort level and completeness of dissection.

Single-stage choanal atresia repair in the neonate.

OBJECTIVE: To evaluate the postoperative results of patients treated with and without the use of stents at the time of initial surgical treatment of choanal atresia (CA). Surgical treatment of CA in the neonatal period is complicated by postoperative stenosis, often necessitating multiple revision surgical procedures. DESIGN: Retrospective medical record review. SETTING: Tertiary care academic center. PATIENTS: The medical records of 9 patients treated for bilateral CA during the neonatal period were reviewed. All patients were treated with an endoscopic approach. Outcomes were compared for patients with and without stent use at the initial operation. MAIN OUTCOME MEASURES: Medical records were analyzed for diagnostic modality, clinical symptoms, age at surgery, sex, surgical repair, placement of stents, reoccurrence of atresia, follow-up time, and postoperative outcomes. RESULTS: The mean age at initial surgery was 8 days (range, 5-15 days). Four patients had endotracheal tube stents placed at the time of initial surgery for a duration of 4 to 6 weeks. All patients required at least 1 additional surgery (mean, 2.6 procedures), and 3 (75%) had restenosis during infancy. The mean follow-up time for this group was 7.5 months. Five patients did not have stents placed at the time of initial surgery. None of these patients required additional surgical procedures during infancy, and none developed restenosis. The follow-up time for this group was 2.5 months. CONCLUSIONS: This study suggests that the placement of stents for bilateral CA repair during the neonatal period results in a high rate of restenosis as well as the need for multiple subsequent procedures during infancy. The use of an endoscopic approach without stent placement appears to result in superior healing without the need for revision surgery.

Utility of preoperative high-resolution CT and intraoperative image guidance in identification of cerebrospinal fluid leaks for endoscopic repair.

BACKGROUND: Endoscopic repair of cerebrospinal fluid (CSF) leaks is a well-established procedure. The radiological workup and use of intraoperative image guidance (IGS), lumbar drain (LD), and intrathecal fluorescein (IF) are less universally accepted. This study examines endoscopic repair of CSF leaks using preoperative high-resolution CT (HRCT) and intraoperative IGS without IF or LD. METHODS: Retrospective review was performed of a single surgeon experience between September 2002 and January 2007. RESULTS: Forty-two anterior skull base defects in 40 patients were repaired endoscopically. The etiology of CSF leaks was traumatic in 5, spontaneous in 12, and iatrogenic in 25 defects (15 from endoscopic sinus surgeries and 10 from neurosurgical procedures). Fifty-two percent of defects presented with a meningoencephalocele. Defect location was sphenoid sinus (17 defects), ethmoid roof (14 defects), cribriform plate (9 defects), and frontal sinus (2 defects). Defect size ranged from 1x1 mm to 2x2 cm. Follow-up ranged from 8 to 46 months. All defects were identified preoperatively on HRCT with successful intraoperative IGS localization. No patients required IF for identification of CSF leak. Overall successful repair was achieved in 40 (95%) defects after initial repair, and 100% after revision. Seven patients had LD, 6 patients were early in the series. Twenty-three patients were discharged the day after surgery and 6 patients were discharged on day 2. CONCLUSION: Using preoperative HRCT for diagnosis and intraoperative IGS for localization, even small skull base defects can be definitively identified. High success rates and early discharges are achieved without additional procedures such as IF or LD. This is a less invasive and more cost-efficient method of repairing CSF leaks.

Pathophysiology of nasal polyposis: the role of desmosomal junctions.

BACKGROUND: Many mucosal inflammatory conditions are associated with alterations in epithelial intercellular junctions and barrier function; however, little is known about the role of intercellular junctions in inflammatory diseases of the upper airways. In this study, we examined nasal polyps for altered intercellular junctions and protein expression. METHODS: Biopsy specimens of nasal polyps and normal tissue were obtained intraoperatively from 11 patients and 6 controls. Tissue was analyzed for expression of intercellular junctional proteins by immunofluorescence. In parallel, cultured human bronchial epithelial (HBE) cells were treated with tumor necrosis factor (TNF) alpha, interferon (IFN) gamma, and IL-13 to simulate inflammatory conditions followed by assessment for changes in junctional proteins by immunofluorescence and Western blot. RESULTS: Of the intercellular junctional proteins analyzed, including proteins comprising tight and adherens junctions, the only alterations observed were in desmosomal proteins in nasal polyp epithelium compared with normal controls. Specifically, expression of desmosomal proteins DSG2 and DSG3 were significantly decreased in polyps versus controls (0.53 pixel/microm2 versus 1.09 pixel/microm2 [p = 0.009], and 0.29 pixel/microm2 versus 1.11 pixel/microm2 [p = 0.0078], respectively). In vitro experiments involving exposure of cultured HBE cells with inflammatory cytokines revealed that TNF-alpha treatment resulted in internalization and decreased expression of DSG2 by immunofluorescence and Western blotting. Treatment with IFN-gamma resulted in increased expression of DSG2 and evidence of protein cleavage by Western blot. IL-13 exposure resulted in down-regulation of DSG2 expression and evidence of protein cleavage. CONCLUSION: These results indicate that nasal polyps express decreased levels of DSG2 and DSG3 components of desmosomal junctions. This is likely linked to the mucosal inflammatory response. Exposure of a respiratory cell line to Th1/Th2 cytokines results in similar expressional alterations in DSG2, suggesting protein internalization and cleavage. We speculate that weakened desmosomal junctions in nasal mucosa secondary to inflammatory cytokines may contribute to the formation of nasal polyposis.