Endoscopic Transnasal Study of the Infratemporal Fossa

Objective

1)Introducing a new endoscopic orientation to the medial portion of the infratemporal fossa (ITF) which is not infrequently involved in sinonasal and related skull base pathologies. 2) Describing the anatomical details and measurement variations of some key ITF landmarks from the unique transnasal endoscopic perspective.

Methods

Using an extended endoscopic approach, the pterygopalatine and infratemporal fossae were dissected in 10 sides of 5 adult cadaver heads. After an extended transethmoid and transmaxillary approach, a plane of dissection along the pterygoid base and the infratemporal surface of the greater sphenoid wing was developed. The related masticatory muscles were dissected through the endoscopic approach. High quality images have been produced by coupling the video camera to a digital recording system.

Results

The foramen rotundum, ovale and spinosum were identified and new landmarks were described from the surgical endoscopic point of view. The sphenomandibularis muscle, recently named in anatomic literature, was also highlighted. Along with various neurovascular structures, the maxillary and mandibular divisions of the trigeminal nerve as well as the middle meningeal artery were identified. Columellar measurements to the foramen rotundum and ovale ranged from 6.1 to 8.0 cm for the former and 7.0 to 9.1 cm for the latter, with a mean of 6.75 cm and 7.78 cm respectively.

Conclusions

The current study provides a novel endo-scopic orientation to the medial ITF. Such knowledge should provide an anatomic basis for experienced surgeons to endo-scopically address this complex region with more safety and efficacy.

Endoscopic endonasal study of the maxillary nerve: a new orientation

BACKGROUND

Endoscopic endonasal procedures for advanced lesions involving the pterygopalatine fossa (PPF) and its various communications are increasingly performed. The maxillary division of the trigeminal nerve (V2) passes through the foramen rotundum and crosses the upper part of the PPF, with a risk of partial or complete injury during surgery in this complex region. Despite the available knowledge of the sinonasal anatomy, the endoscopic orientation of the V2 remains unclear and requires further analysis from this unique view.

METHODS

Using an extended endoscopic approach, the PPF was dissected in 20 sides of 10 adult cadaver heads. The V2 also was followed anteriorly from the trigeminal ganglion, toward the infraorbital canal. The course and the neurovascular relationships of the V2 were studied. High-quality endoscopic images have been produced by coupling the video camera to a digital video recording system.

RESULTS

The endoscopic course and relations of the V2 were carefully described. Important landmarks to identify and avoid injury of the nerve were discussed in relation to this unique view.

CONCLUSION

This study updates our understanding of the V2 anatomy from an endoscopic perspective. The medial to lateral inclination and drooping of the V2, as well as different relationships of the V2 with the vascular structures are important findings to be taken into consideration while endoscopically addressing related lesions.

Endoscopic reconstruction of large anterior skull base defects using acellular dermal allograft

BACKGROUND

Endoscopic repair of small- to medium-sized anterior skull base (ASB) defects using bone, cartilage, fascia, fibrin glue, lipolized dura, and, more recently, acellular dermal allograft have all been described with equal efficacy. The purpose of this study was to review our experience with the use of acellular dermis as the sole graft material in endoscopic reconstruction of large ASB defects.

METHODS

A retrospective chart review of all patients who underwent endoscopic repair of ASB defects at the University of Miami between the years of 2001 and 2006 was conducted. Fifty-six patients were identified who met these criteria. All repairs were performed by a transnasal, endoscopic approach. Outcome measures included success of graft take and incidence of major and minor complications. Dural defect size was defined as small (<0.4 cm), intermediate (0.4-2.0 cm), and large (>2.0 cm).

RESULTS

AlloDerm (AlloDerm. LifeCell Corp. Woodlands, TX) was used as the primary graft material in 30/55 (55%) cases; 16/55 (29%) of the repaired defects were classified as large. Graft success was 97% in the AlloDerm group and 92% in the non-AlloDerm group. The incidence of major and minor complications in the AlloDerm group was 0 and 3.3%, respectively. In the non-AlloDerm group, the incidence of major and minor complications was 4 and 12%, respectively. There were no statistical differences in the complication rates based on the type of repair or defect size.

CONCLUSION

Alloderm can be used successfully to repair ASB defects, including large defects that are >2 cm in size with little or no morbidity.

Endoscopic endonasal study of the internal carotid artery course and variations

BACKGROUND

With the advance in endoscopic sinus surgery, more procedures are being performed to address challenging lesions and, of particular concern, those around the internal carotid artery (ICA). Despite the current progress in the understanding of endoscopic paranasal sinus anatomy, little information is available about the course and variations of the closely related ICA as seen endoscopically. In this study, we show an endoscopic analysis of the ICA course in a series of advanced endoscopic dissections

METHODS

Ten cadaver heads (20 sides) have been endoscopically dissected. Using an extended approach, a wide sphenoidotomy has been performed as far laterally as the pterygoid base. The latter also has been drilled posteriorly and the ICA was fully exposed from its petrous part up to its termination below the anterior perforated substance of the brain. High-quality endoscopic pictures were produced by coupling the video images with a digital recording system.

RESULTS

The ICA course, landmarks, and segments have been defined and analyzed. The ICA was found to have a variable course that was well appreciated using the multiangled, magnified endoscopic view. The importance of such variation was established in relation to the nearby anatomic structures as well as possible lesions involving this area.

CONCLUSION

The results of this study provide the endoscopic sinus and skull base surgeon with a better understanding of the endoscopic course and variations of the ICA. In experienced hands, such endoscopic orientation should allow safer as well as more effective management of closely related lesions.

The voice and laryngeal dysfunction in stroke: a report from the Neurolaryngology Subcommittee of the American Academy of Otolaryngology-Head and Neck Surgery

OBJECTIVE

Stroke is the third leading cause of death in the United States, behind heart disease and cancer. It affects as many as 5% of the population over 65 years old, and this number is growing annually due to the aging population. A significant portion of stroke patients that initially survive are faced with the risk of aspiration, as well as quality-of-life issues relating to impaired communication. The goal of this paper is to define the scope of practice in otolaryngology for these patients, and to review pertinent background literature.

STUDY DESIGN

Consensus report and retrospective literature review.

RESULTS

Otolaryngology involvement in these patients is critical to their rehabilitation, which often requires an interdisciplinary team of specialists. This committee presentation explores epidemiological data regarding the impact of stroke and its complications on hospitalizations. A pertinent review of neuroanatomy as it relates to laryngeal function is also discussed. State-of-the-art diagnostic and therapeutic procedures are presented.

CONCLUSION

There is a well-defined set of diagnostic and therapeutic options for laryngeal dysfunction in the stroke patient.

SIGNIFICANCE

Otolaryngologists play a critical role in the interdisciplinary rehabilitation team.

Surgical outcomes and safety of transnasal endoscopic resection for anterior skull tumors

OBJECTIVE

To report the surgical outcomes and safety of transnasal endoscopic resection (TER) for anterior skull base (ASB) tumors.

STUDY DESIGN AND SETTING

A retrospective chart review to identify patients undergoing TER for ASB tumors at a tertiary care medical center between September 1997 and June 2006.

RESULTS

Nineteen patients underwent TER for ASB tumors without open craniotomy. There were 17 malignant and two benign lesions. Olfactory neuroblastoma was the most common pathology, occurring in 53 percent of patients. One patient recurred locally, resulting in an overall local control rate of 94.7 percent for all neoplasms and 94.1 percent for malignant disease. It should be noted that the tumor control rate may be premature given the small sample size and limited follow-up. Overall, there were 16 complications, but only two of these, an orbital hematoma and a frontal lobe abscess, were considered major complications directly attributable to surgery.

CONCLUSIONS

TER for ASB tumors appears to be safe in properly selected patients. In light of the small sample size and limited follow-up, the major complication rate directly attributable to surgery was 11 percent, and the overall local control rate was 95 percent. A larger multi-institutional series with longer follow-up is warranted.

Frozen-section biopsy analysis for acute invasive fungal rhinosinusitis

OBJECTIVE

To evaluate sensitivity and specificity of frozen-section biopsy in the diagnosis of acute invasive fungal rhinosinusitis (AIFRS).

STUDY DESIGN AND SETTING

Retrospective chart review of all patients treated for AIFRS at the University of Miami between 1993 and 2005. Twenty patients with the clinical diagnosis of AIFRS were identified. Histopathological data were collected to evaluate the use of frozen-section biopsy to diagnose the disease.

RESULTS

Permanent pathology sections were positive for AIFRS in all specimens. Frozen-section biopsies were positive for fungal features in all but five cases (four with Mucor and one with Aspergillus). High positive predictive values were found for both fungal types and for both sets of patients (bedside and intraoperative).

CONCLUSION

Frozen-section biopsy is a useful tool for rapid and effective diagnosis in patients with suspected AIFRS. A positive frozen-section result is highly predictive of invasive disease and merits prompt surgical intervention.

Sphenoid sinus chondromyxoid fibroma mimicking a mucocele

We report the case of a 44-year-old man who presented with a chondromyxoid fibroma (CMF) of the sphenoid sinus, which filled the sinus and clinically and radiologically resembled a mucocele. Chondromyxoid fibromas are the least common cartilaginous neoplasms of bone, typically occurring in the metaphysis of long bones. They have occasionally been described in the facial bones, usually the mandible and maxilla, and rarely involve the paranasal sinuses. Chondromyxoid fibroma displays a relatively unique histological appearance, with characteristic lobulation, with spindle to stellate cells embedded in a myxoid or chondroid matrix. The periphery of the lobules tends to be more cellular than the center. Despite having been described nearly 60 years ago, the histogenesis of CMF remains controversial. Although CMFs are generally regarded as benign neoplasms, they may show an infiltrative pattern and may recur, particularly when they are in locations where complete surgical excision may be difficult or impossible.

Reliability of the University of Miami chronic rhinosinusitis staging system

BACKGROUND

The aim of this study was to determine the interrater reliability and correlation between computed tomography (CT) and endoscopic components of the University of Miami (UM) Chronic Rhinosinusitis Staging System (UMCRSS), a comprehensive staging system for chronic rhinosinusitis (CRS).

METHODS

A prospective analysis of 55 patients undergoing endoscopic sinus surgeryfor CRS was performed. The population consisted of 28 men and 27 women, with a mean age of 45.9 years. All patients underwent staging, via the CT and endoscopic components of the UMCRSS in the operating room, by three examiners. The reliability of the system and all of its components was determined by kappa-coefficient analysis, comparing the data from all three examiners. Correlation between the CT and endoscopic arms was analyzed by Pearson's product moment coefficient.

RESULTS

Interrater reliability for the CT arm (kappa = 0.83) and endoscopic arm (kappa = 0.74 for the revision population, and kappa = 0.72 for the primary surgery population) were found to be significant. Endoscopic staging established significant correlation with CT staging (Pearson's r2 = 0.40; p < 0.0001 overall, 0.57, p < 0.0001 for revision, and 0.42, p < 0.0001 for primary cases).

CONCLUSION

The UMCRSS is a comprehensive and reliable staging system with very strong and positive correlation between the CT and endoscopic components.

Microdebriders used in functional endoscopic sinus surgery: secondary analysis and validation of a new tissue model

OBJECTIVES/HYPOTHESIS

To validate a previously reported in vitro tissue model for microdebrider comparison and determine which microdebrider, tissue type, blade type, and suction strength is most efficient. Specifically, the goal of the secondary analysis is to expand on the results of the preliminary analysis by increasing the sample size, and introduce an aspiration efficiency score (AES) to facilitate microdebrider comparison.

STUDY DESIGN

Prospective randomized comparison.

METHODS

A prospective randomized comparison of the Diego Powered Dissector and XPS 3000 Powered ENT System was conducted using a soft tissue and a firm tissue model. In addition to evaluating tissue aspiration with straight and angled blades, clogging rates and clearance times were measured. Both standard wall suction and liposuction were used. Basic statistical analysis, a one-way analysis of variance, and a post hoc Student's t test were performed to compare outcomes.

RESULTS

With standard wall suction, the microdebriders were equivalent for the overall microdebrider comparison. For the ''head to head'' comparison with standard wall suction, the devices were also equivalent when using the straight blades, but the XPS 3000 aspirated more tissue when using the angled blades. With liposuction, the XPS 3000 and liposuction independently aspirated more tissue but clogged more often compared with the Diego PD and regular suction. The aspiration efficiency of soft tissue (oysters) and straight blades was superior compared with firm tissue (scallops) and angled blades. For the ''head to head'' comparison with liposuction, the XPS 3000 aspirated more tissue regardless of tissue type, but the Diego PD clogged less with firm tissue (scallops). Overall, the AES favored the XPS 3000, soft tissue (oysters), straight blades, and liposuction.

CONCLUSION

Our tissue model represents a reliable and reproducible means of microdebrider comparison. Statistically significant differences between the Diego PD and XPS 3000, as well as between tissue types, blade types, and suction strengths, are reported. Using these results, microdebrider manufacturers can adopt similar tissue models, expand on the current AES, and include other commercially available microdebrider devices to test and report product performance to the consumer. Perhaps an optimal open to closed ratio or liposuction pressure can be determined that yields the greatest tissue aspiration with the fewest number of clogs.

The role of atypical bacteria in chronic rhinosinusitis

OBJECTIVE

This study examines the presence of atypical bacteria in chronic rhinosinusitis (CRS) by utilizing the polymerase chain reaction (PCR).

STUDY DESIGN AND SETTING

Eleven patients with CRS were prospectively enrolled. DNA was isolated from the mucosa samples and subjected to PCR using oligonucleotides specific for identification of atypical bacteria including: Mycoplasma pneumoniae, Chlamydia pneumoniae, and Legionella pneumophila. Also, routine aerobic and anerobic cultures were processed. Sinus tissue samples from 6 fresh corpses without evident sinus disease served as controls.

RESULTS

No atypical bacteria were identified in the 11 patient samples by PCR. One of 6 cadaver controls was positive by PCR for M pneumoniae. The most common organism obtained from routine culture was coagulase negative staphylococci.

CONCLUSION

Using sensitive PCR techniques, CRS mucosa did not reveal DNA from M pneumoniae, C pneumoniae, or L pneumophila.

SIGNIFICANCE

Atypical bacteria were not identified in patients with CRS despite highly effective PCR methods and they may not play a significant role in the cause of CRS.

Endoscopic sinus surgery for benign and malignant nasal and sinus neoplasm

PURPOSE OF REVIEW

Endoscopic sinus surgery has become widely accepted as the standard of treatment for chronic inflammatory diseases of the paranasal sinuses unresponsive to medical treatment. With increased skill with endoscopic surgical technique, advanced technologies such as intraoperative imaging systems, and a better understanding of the complex anatomy of the paranasal sinuses and surrounding vital structures, many otolaryngologists have increasingly applied their expertise in endoscopic sinus surgery to the resection of nasal and sinus neoplasms. The following represents a review of the recent literature on the latest trends regarding endoscopic resection of nasal and paranasal sinus neoplasms.

RECENT FINDINGS

There has been an increasing popularity in the removal of nasal and paranasal sinus neoplasms through an endoscopic approach. In the recent literature, emphasis has been on the endoscopic surgery of benign tumors, especially inverted papilloma and nasopharyngeal angiofibroma. Other benign neoplasms have also been reported, but only in small case reports. There have been a few recent reports supporting endoscopic removal of malignant neoplasms as well. However, the follow-up is too short and study groups too small to make definitive conclusions.

SUMMARY

In the hand of experienced and skilled surgeons, complete endoscopic removal is attainable in most cases. Especially for the more common benign neoplasms, such as inverted papilloma and early stage angiofibroma. En bloc resection is not necessary to achieve oncologic cure. However, several factors have to be considered before selection of this surgical approach. Large tumor size, intracranial or orbital extension, and extensive frontal or infratemporal fossa involvement are relative, but not absolute limitations.

Endoscopic management of anterior skull base tumors

Anterior craniofacial resection has become a standard procedure for management of lesions of the anterior skull base. During the last 2 decades, modifications of the classic anterior craniofacial resection have been reported. With the introduction of endoscopic sinus techniques and instrumentation, surgeons have begun to use endoscopic approaches for management of anterior skull base lesions. This article describes endoscopic modifications of anterior craniofacial resection.

Can Maximum Phonation Time Predict Voice Outcome after Thyroplasty Type I?

BACKGROUND

Thyroplasty type I, as introduced by Isshiki and colleagues almost 30 years ago, has become the gold standard of improving glottal incompetence caused by unilateral vocal fold paralysis. Intraoperative assessment of the adequacy of glottal closure is subjective and based on the perceptual judgment of vocal quality and degree of improvement in glottal gap size.

OBJECTIVE/HYPOTHESES

The primary purpose of this study was to investigate whether the intraoperative measurement of maximum phonation time (MPT) is an adequate predictor of voice outcome after thyroplasty type I. To assess this possibility, it was necessary to evaluate the effect of body posture (seated vs. supine) and anesthesia (none vs. light sedation) on the measure of MPT.

STUDY DESIGN

A prospective study of 20 individuals with unilateral vocal fold paralysis was undertaken.

METHODS

Subjects were assessed at three time points: pre-, intra-, and postoperatively across parameters of breathiness rating, glottal gap size, glottal flow rate, and MPT.

RESULTS

Results indicated that MPT was significantly lower in the supine versus seated position. In addition, light sedation resulted in a trend toward lower MPT that was not statistically significant. Finally, the intraoperative measurement of MPT, although lower than a 1-month postoperative measurement, was significantly predictive of the outcome.

CONCLUSIONS

The intraoperative measure of MPT appears to be an adequate predictor of the postoperative outcome.

Tissue Model and Preliminary Analysis of Microdebriders Used in Endoscopic Sinus Surgery

Objectives: In 1999, Ferguson reported the first and only quantitative analysis of microdebriders used in ESS. The purpose of our study was to establish a standardized in vitro model and compare the newer “next-generation” microdebriders to determine which device and combination of tissue type, blade, and suction strength was most efficient for this model.

Methods: The Gyrus-Diego-Powered-Dissector and Xomed-XPS-3000-Powered-ENT-System were compared using a soft tissue model consisting of raw oysters (nasal polyps) and a firm-tissue model consisting of scallops mixed with eggshells (nasal/sinus tissue). In addition, the effect of blade type (straight/60) and suction strength (wall-suction/liposuction) on aspiration efficiency was evaluated. Aspiration efficiency was quantified by 3 outcomes (tissue aspiration, clog-frequency, and clearance time).

Results: For the “head-to-head” comparison, Xomed was statistically superior for soft tissue/oyster aspiration when using the straight blade regardless of suction strength and when using the angled blade with liposuction. Although not statistically significant, several trends were observed in our analysis. First, Gyrus appeared to be superior to Xomed for firm-tissue/scallop aspiration, clog-frequency, and clearance time. In addition, straight blades appeared to be superior to angled blades for overall tissue aspiration, clog frequency, and clearance time. Finally, liposuction appeared to be superior for both soft tissue/oyster and firm tissue/scallop aspiration, but wall-suction demonstrated less clogging and clearance time.

Conclusion: The tissue model presented appears to be both reliable and reproducible. Only 2 statistically significant results were observed, however, several trends toward significance were noted. A second study with a larger sample size and more advanced statistical analysis is needed to better delineate these trends.