ORIGINAL ARTICLE
Practice paerns in endoscopic skull base surgery: survey of the American Rhinologic Society Jivianne T. Lee, MD1,2 , Todd T. Kingdom, MD3 , Timothy L. Smith, MD, MPH4 , Michael Setzen, MD, FACS5,6 , Seth Brown, MD7,8 and Pete S. Batra, MD, FACS9
Background: The introduction of advanced endoscopic techniques has facilitated significant growth in the field of endoscopic skull base surgery (SBS). The purpose of this study is to evaluate the impact of endoscopic SBS on the clinical practice paerns of the American Rhinologic Society (ARS) membership.
observed, with open skull base (32%), unlisted endoscopic (29%), sinus surgery (24%), and unlisted neurosurgical (15%) codes employed by surgeons. Only 29% of physicians reported adequate reimbursement in ≥75% of cases. Eightyfive percent of respondents supported creation of dedicated endoscopic SBS codes.
Methods: A 23-item survey veed by the ARS Board of Directors was electronically disseminated to the ARS membership from February 5, 2013, to March 31, 2013. The target group encompassed 982 ARS members.
Conclusion: This study illustrates the widespread integration of endoscopic SBS procedures into rhinologic clinical practice among survey respondents. However, current variability in coding strategies and inadequate reimbursement may warrant development of specific guidelines to stanC 2013 dardize coding and billing processes in the future.
Results: A total of 152 physicians (15.5%) completed the survey. Open and endoscopic skull base procedures were performed by 41% and 94% of the respondents, respectively. During a typical year, the number of endoscopic skull base cases ranged from 0 to 20 in 56%, 21 to 50 in 26%, 51 to 100 in 9%, and >100 in 8%. Endoscopic cerebrospinal fluid (CSF) leak repair (96%) and transsphenoidal pituitary surgery (81%) were the most commonly performed procedures, followed by transcribriform (68.4%), transplanum (54.4%), and transclival (49.6%) approaches. Overall, 69.6% used endoscopy for resections of malignant sinus/skull base lesions. Considerable variation in Current Procedural Terminology (CPT) coding philosophy was
W
ith continual advances in endoscopic instrumentation and techniques, in recent years we have
1 Department
of Otolaryngology–Head and Neck Surgery, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, CA; 2 Orange County Sinus Institute, Southern California Permanente Medical Group (SCPMG), Irvine, CA; 3 Department of Otolaryngology, University of Colorado, Aurora, CO; 4 Department of Otolaryngology–Head and Neck Surgery, Oregon Health and Science University, Portland, OR; 5 New York University School of Medicine, New York, NY; 6 Department of Otolaryngology, North Shore University Hospital, Manhasset, NY; 7 Division of Otolaryngology, University of Connecticut School of Medicine, Hartford, CT; 8 Connecticut Sinus Institute, Hartford, CT; 9 Department of Otolaryngology–Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, TX Correspondence to: Jivianne T. Lee, MD, 6670 Alton Parkway, Irvine, CA 92618; e-mail: [email protected]
ARS-AAOA, LLC.
Key Words: endoscopy; skull base; surgery; data collection; practice paern
How to Cite this Article: Lee JT, Kingdom TT, Smith TL, Setzen M, Brown S, Batra PS. Practice paerns in endoscopic skull base surgery: survey of the American Rhinologic Society. Int Forum Allergy Rhinol. 2014;4:124–131.
witnessed significant expansion, innovation, and evolution in the field of endoscopic skull base surgery (SBS). Although once primarily restricted to management of benign sinonasal and skull base pathology (ie, juvenile nasopharyngeal angiofibroma, inverted papilloma), the spectrum of applications for endoscopic approaches has broadened considerably to encompass progressively larger, more complex lesions as well as anterior skull base malignancies.1–7
Funding sources for the study: Research grant (NIH, National Institute on Deafness and Other Communication Disorders [NIDCD] 2R01 DC005805); Research grants (ARS, Medtronic). Potential conflict of interest: None provided. Received: 12 August 2013; Revised: 22 September 2013; Accepted: 26 September 2013 DOI: 10.1002/alr.21248 View this article online at wileyonlinelibrary.com.
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In a recent survey of the North American Skull Base Society (NASBS), endoscopic SBS was performed by 80% (60/75) of respondents, with 32% reporting between 20 and 50 cases in a typical year.8 However, the study mainly targeted practicing skull base surgeons, including otolaryngologists (53%) and neurosurgeons (44%).8 The integration of endoscopic skull base procedures into rhinologic clinical practice has yet to be fully characterized. The purpose of the current survey was to evaluate the impact of endoscopic SBS on the clinical practice patterns of the American Rhinologic Society (ARS) membership. The proportion of surgical practice devoted to SBS and the types of endoscopic skull base approaches most frequently performed was investigated. In addition, economic aspects including Current Procedural Terminology (CPT) coding and reimbursement issues were also assessed. Finally, comparative analysis of data retrieved from the NASBS and ARS surveys was also conducted.
Materials and methods A 23-item written survey exploring endoscopic SBS practice patterns was created and vetted by the ARS Patient Advocacy Committee and Board of Directors. The questionnaire was electronically disseminated to the general ARS membership biweekly from February 5, 2013, to March 31, 2013. The target group encompassed 982 ARS members. Demographic characteristics of the respondents were determined, including geographic location, duration in practice (years), and type of clinical practice (academic, multispecialty, single-specialty group, solo). Geographic regions for the survey were defined as follows: New England (Maine, Vermont, New Hampshire, Massachusetts, Connecticut, Rhode Island), Mid-Atlantic (New York, New Jersey, Pennsylvania), Mountain (Wyoming, Idaho, Montana, Nevada, Utah, Colorado, New Mexico, Arizona), North central (North Dakota, South Dakota, Nebraska, Kansas, Missouri, Iowa, Minnesota, Wisconsin, Illinois, Michigan, Indiana, Ohio), South central (Texas, Oklahoma, Arkansas, Kentucky, Tennessee, Mississippi, Alabama, Louisiana), Southeast (Maryland, Delaware, Virginia, West Virginia, North Carolina, South Carolina, Georgia, Florida), and West coast (Washington, Oregon, California, Alaska, Hawaii). Skull base surgical practice patterns were assessed, including affiliation with a dedicated skull base program, proportion of clinical practice devoted to SBS, and number of open and endoscopic SBS cases performed annually. In addition, use of specific endoscopic skull base techniques was determined, with procedures stratified into cerebrospinal fluid (CSF) rhinorrhea repair and the respective transnasal corridor (transsphenoidal, transcribriform/transethmoid, transplanum, and transclival) approaches. Endoscopic resection of malignant lesions was also evaluated, with respondents asked to report the percentage of sinonasal and skull base malignancies that were managed endoscopically in lieu of open procedures. Finally, socioeconomic aspects
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were examined, such as coding strategies and reimbursement issues. Percentages for each response were calculated based on the number of respondents for each question. Since not all survey respondents answered every question, the response rate per question ranged from 117 to 152. Statistical analysis was performed using Fisher’s exact test to examine significant differences in variables between the 2 groups. SAS version 9.2 (SAS Institute Inc., Cary, NC) was used. A p value 30 years (14, 9.2%). A majority of respondents practiced in an academic setting (84, 55.3%), whereas 43 (28.3%), 14 (9.2%), and 11 (7.2%) were part of single-specialty, multispecialty, or solo practices, respectively. Eighty-three (54.6%) were affiliated with a designated skull base surgery program, and 101 (66.5%) reported working with residents and/or fellows. The percentage of surgical practice devoted to SBS was as follows: 0% to 25% (100, 65.8%), 26% to 50% (21, 13.8%), 51% to 75% (8, 5.3%), and >75% (2, 1.3%). Twenty-one (13.8%) did not perform SBS and were excluded from further analysis. Open and endoscopic skull base procedures were performed by 55 of 136 (40.4%) and 125 of 133 (94%) of the responding surgeons, respectively. An overwhelming majority (124, 91.9%) performed less than 20 open skull base procedures annually, with only 6 (4.4%), 4 (3%), 0 (0%), and 1 (0.7%) physicians completing 21 to 50, 51 to 75, 76 to 100, and >100 cases per year, respectively. In contrast, the number of endoscopic skull base cases was much higher, with 75 (56.4%) performing less than 20 procedures annually, and 35 (26.3%), 5 (3.8%), 7 (5.3%), and 11 (8.3%) physicians completing 21 to 50, 51 to 75, 76 to 100, and >100 cases per year, respectively, as illustrated in Figure 2. Endoscopic CSF leak repair (129, 95.6%) and transsphenoidal pituitary surgery (110, 80.9%) were the most common procedures performed, followed by transcribriform/transethmoid (93, 68.4%), transplanum (74, 54.4%), and transclival (67, 49.6%) approaches. In addition, 94 of 135 (69.6%) physicians used endoscopy in the resection of malignant sinonasal and skull base lesions, with 34 (26.1%) doing so in >75% of cancer cases. Data regarding the number and types of endoscopic SBS procedures performed by responding surgeons are shown in Figure 3. Considerable variation in CPT coding philosophy for endoscopic SBS was observed for the 117 reporting
Lee et al.
FIGURE 1. Geographic location of 152 respondents reported as a percentage of the total number of responses.
FIGURE 2. Range of open and endoscopic skull base procedures performed by respondents in a typical year.
physicians. Open SBS (37, 31.6%), corresponding endoscopic sinus surgery (34, 29.1%), unlisted sinus surgery31299 (29, 24.8%), unlisted neurosurgical-64999 (17, 14.5%), codes were all used, as demonstrated in Figure 4. Coding strategies for nasoseptal flap reconstruction were also variable, with 55 (47%) using secondary dural repair (61619), 20 (17.1%) using unlisted codes, and 19 (16.2%) using a neurovascular pedicle flap (15750) code. However, coding for clinic debridements following endoscopic SBS was fairly consistent, with a majority (86, 69.4%) of participants using 31237. Twenty (16%) respondents did not bill for debridement, whereas 6 (4.8%) and 12 (9.7%) physicians used an unlisted code or 58 modifier, respectively. In terms of reimbursement, 40 (32.8%), 24 (19.7%), 23 (18.9%), and 35 (28.7%) of 122 surgeons felt that com-
pensation was adequate in 0% to 25%, 26% to 50%, 51% to 75%, and >75% of cases, respectively. Overall, 113 of 133 (85%) respondents advocated the creation of new, dedicated endoscopic SBS codes. Univariate analysis (Fisher’s exact test) revealed that type or duration of clinical practice, skull base program affiliation, proportion of surgical practice devoted to SBS, and performance of open or endoscopic SBS had no statistical impact on physician support of new code formation. Only the “percentage of time adequate reimbursement was received” significantly influenced member approval of new codes, with physicians who obtained satisfactory compensation >50% of the time less likely to advocate the development of dedicated endoscopic SBS codes (p = 0.0093) (Table 1).
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FIGURE 3. Percentage of 136 respondents performing each of the respective endoscopic skull base procedures listed in their clinical practice.
FIGURE 4. Coding strategies used by 117 reporting surgeons. CPT = correct procedural terminology.
Comparative analysis of NASBS vs ARS survey data is summarized in Table 2. A statistically greater proportion of NASBS surgeons were found to be affiliated with a skull base surgery program (84% NASBS vs 60% ARS; p = 0.0007), operated in an academic setting (84% NASBS vs 59% ARS; p = 0.0003), performed open SBS (89% NASBS vs 41% ARS; p = 0.0001), and devoted a higher percentage of their surgical practice to skull base procedures (p = 0.0001) in comparison to ARS respondents. Thirty-seven percent of NASBS responders spent >50% of their operative time performing SBS vs 8% of ARS physicians. Similarly, transsphenoidal (95% NASBS vs 81% ARS, p = 0.0086) and transclival (66% NASBS vs 50% ARS, p = 0.0444) approaches were also conducted by a larger number of NASBS survey participants than ARS respondents. However, the number of surgeons performing endoscopic SBS (p = 0.5287), transcribriform (p = 0.868), and transplanum (p = 0.1619) procedures were not statis-
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tically different between the 2 societies. In addition, no significant disparities with respect to CPT coding strategies for SBS were observed (p = 0.937), with an assortment of codes (ie, open SBS, sinus surgery, unlisted endoscopic, unlisted neurosurgical, etc.) used by members of both organizations. Finally, although a lower percentage of NASBS surgeons reported adequate reimbursement >50% of the time compared to ARS responders (31% NASBS vs 48% ARS, p < 0.0001), a statistically equivalent proportion of participants from both surveys (87% NASBS vs 85% ARS; p = 0.8366) advocated the introduction of dedicated endoscopic SBS codes.
Discussion The field of endoscopic SBS has experienced significant growth and development in recent years with the emergence of more advanced endoscopic techniques and
Lee et al.
TABLE 1. Univariate analysis of variables impacting support
TABLE 2. Comparative analysis of NASBS vs ARS data
for new skull base codes Variable Variable
Yes (n = 113)
No (n = 20)
Years of practice
p
0.8087
50%
10 (9)
20 (100)
0.1409
Yes
50 (44)
5 (25)
No
63 (56)
15 (75)
Perform endoscopic skull base surgery 104 (95)
19 (95)
No
6 (5)
1 (5)
Percent of time receiving adequate reimbursement
37 (54) 78 (59)
≥10 years
31 (46) 61 (46)
Academic
57 (84) 78 (59)
Private
11 (16) 55 (41)
Yes
57 (84) 80 (60)
No
11 (16) 53 (40)
5 (26)
>50% of time
44 (43)
14 (74)
0.0001
≤50%
43 (63) 120 (92)
>50%
25 (37)
10 (8) 0.0001
Yes
59 (89) 55 (41)
No
7 (11)
78 (59) 0.5287
Yes
57 (86) 123 (95)
No
9 (14)
Yes No
59 (57)
0.0007
7 (5)
Perform transsphenoidal approaches 0.0093
≤50% of time
0.0003
Perform endoscopic skull base surgery 1.0000
Yes
25% of their operative time to skull base procedures. Endoscopic SBS (84%) was much more commonly performed than open SBS (40.4%). During a typical year, only 4.4% and 3.6% survey participants performed 21 to 50 and >50 open skull bases cases, respectively. In contrast, the number of endoscopic skull base surgeries was much higher, with 26.3% and 17.4% surgeons performing 21 to 50 and >50 cases per year, respectively. The preponderance of endoscopic over open SBS was not unexpected given the demographics of the target group, which was comprised primarily of otolaryngologists with a clinical focus in rhinology as opposed to solely skull base pathology. Of the endoscopic SBS performed, CSF leak repair (95.6%) and transsphenoidal pituitary surgery (80.9%) were the most commonly reported. This is not unexpected because these are well-established procedures with available dedicated codes that do not require the level of surgical expertise essential for more advanced transnasal corridor approaches.12 However, a significant proportion of respondents also implemented more recently introduced endoscopic skull base procedures, including transethmoid/transcribriform (68.4%), transplanum (54.4%), and transclival (49.6%) approaches. In addition, 69.6% also performed endoscopic resection of sinonasal and skull base malignancies. Of the surgeons, 25% and 26.1% employed endoscopic methods over external techniques in 25% to 75% and >75% of cancer cases, respectively. An increasing number of studies in the literature have demonstrated the successful management of malignant skull base lesions us-
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ing transnasal endoscopic procedures with comparable oncologic outcomes to traditional craniofacial resection.13–21 However, concerns regarding long-term survival and the technical feasibility of achieving complete tumor excision with negative margins have deterred some surgeons from pursuing this surgical option. The current survey is unable to ascertain the precise indications or limitations for use of such endoscopic procedures in the treatment of sinonasal and skull base malignancies. Nonetheless, the widespread adoption of endoscopic SBS in the present study exemplifies a paradigm shift among survey respondents in the operative intervention of malignant sinonasal and skull base lesions, with standard open approaches supplanted by less invasive endoscopic techniques. Economic aspects of endoscopic SBS including CPT coding philosophies and reimbursement issues were also investigated by the survey. Marked variability in coding practices was evident, with open SBS (31.6%), corresponding endoscopic sinus surgery (29.1%), unlisted sinus surgery (24.8%), and unlisted neurosurgical (14.5%) codes all used by reporting physicians to document endoscopic skull base procedures. Similarly, with respect to nasoseptal flap reconstruction, multiple codes were employed including secondary dural repair (47%), unlisted (17.1%), and neurovascular pedicle flap (16.2%) codes. Only coding for clinic debridements following endoscopic SBS was fairly uniform, with a majority (69.4%) of respondents using 31237. Given the lack of standardized CPT codes currently available to accurately describe endoscopic SBS, it is not surprising that such significant heterogeneity in coding strategies exist. Although used by the majority of responding surgeons (61%), open skull base and sinus surgery codes do not appropriately represent the services being performed in endoscopic SBS. Unlisted endoscopic and neurosurgical codes likely signify the best alternatives at the present time. However, procuring compensation for unlisted codes can prove challenging, with extensive documentation and onerous discussions with insurance payers often required to facilitate reimbursement. Such obstacles may have accounted for the fewer number of survey participants resorting to unlisted codes for endoscopic SBS in comparison to open and sinus surgery coding options. In the context of such coding ambiguity, only 28.7% surgeons reported receiving adequate reimbursement in >75% of cases; with 85% respondents advocating the creation of dedicated endoscopic SBS codes. Predictably, the only factor that statistically impacted member support for new code formation was the percentage of time satisfactory compensation was obtained, with surgeons who received adequate reimbursement >50% of the time less likely to be proponents for the establishment of new endoscopic SBS codes. However, it should be noted that study results may have been somewhat compromised by potential selection bias of the target group. Because the survey was disseminated to otolaryngologists who, by virtue of their membership within the ARS, had a specialized interest in clinical rhinology, respondents may have been more likely than
Lee et al.
nonrespondents to practice endoscopic SBS. In addition, surgeons who performed endoscopic skull base procedures may have felt more invested in the study outcome and thus been more inclined to accept the initial invitation to participate. Recall bias may also have contributed to an overestimation of the amount of SBS being performed. Therefore, data from the current ARS survey cannot be extrapolated to the general otolaryngology community. Furthermore, it must be emphasized that survey responses signify the opinions of the participating ARS members only and not the viewpoints of the society as a whole. Nevertheless, as a large proportion of respondents (45%) operated in nonacademic settings, study results demonstrated that integration of endoscopic SBS into rhinologic practice was not exclusive to highly-specialized tertiary care centers. In the comparative analysis of survey data from the NASBS vs ARS, both similarities and differences in practice patterns were identified. A statistically greater proportion of NASBS participants worked in an academic setting and were affiliated with a dedicated skull base surgery program. In addition, significantly more NASBS surgeons performed open SBS and devoted a higher percentage of their surgical practice to SBS than their ARS member counterparts. Such discrepancies likely stem from inherent differences in membership constituency between the 2 societies. Whereas the NASBS is comprised of both neurosurgeons and otolaryngologists with a clinical emphasis in SBS, the ARS is exclusive to otolaryngologists with a principal focus in rhinology. Consequently, it is not surprising that NASBS respondents would engage in more SBS clinical activities overall than ARS physicians. However, with respect to the number of surgeons who performed endoscopic SBS, no statistical differences between NASBS and ARS participants were evident, indicating that rhinologic surgeons have also integrated advanced endoscopic skull base techniques into their operative practice. Although a higher percentage of NASBS members were found to perform transsphenoidal and transclival approaches than ARS responders, the proportion of physicians performing transcribriform and transplanum procedures were not statistically dissimilar between the 2 societies.
Similar issues with coding and reimbursement for endoscopic SBS were encountered by members of both organizations. A wide array of coding policies were exhibited, with no significant differences in code distribution between the 2 groups. Although the percentage of NASBS surgeons (69%) claiming inadequate reimbursement was higher than that of ARS responders (52%), aggregate responses of survey participants indicated support of new endoscopic SBS codes irrespective of societal membership. Eight-seven percent of NASBS and 85% ARS survey respondents advocated the introduction of new, dedicated endoscopic SBS codes, highlighting the overwhelming support for pursuit of such an endeavor by member participants from both organizations. Based upon the findings of this survey, it would be prudent to approach the Physician Payment Policy workgroup (3P) of the American Academy of Otolaryngology–Head and Neck Surgery, with the goal of seeking new and appropriate CPT codes for endoscopic SBS.
Conclusion The present study illustrates the widespread integration of endoscopic SBS in rhinologic clinical practice among survey respondents, with 95% affirming incorporation of endoscopic skull base techniques into their surgical armamentarium. Such advanced endoscopic procedures not only encompassed CSF leak repair and transsphenoidal pituitary surgery, but also the more recently described transcribriform, transplanum, and transclival approaches, as well as resections of sinonasal and skull base malignancies. However, current variability in coding strategies and inadequate reimbursement may warrant the development of dedicated endoscopic SBS codes and specific guidelines to facilitate standardization of coding and billing processes in the future.
Acknowledgments We acknowledge Jeff Slezak, PhD, for his statistical support, and Kevin Welch, MD, for coordinating the electronic dissemination of the survey to the ARS membership.
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Nicolai P, Villaret AB, Farina D, et al. Endoscopic surgery for juvenile angiofibroma: a critical review of indications after 46 cases. Am J Rhinol Allergy. 2010;24:e67-e72. Boghani Z, Husain Q, Kanumuri VV, et al. Juvenile nasopharyngeal angiofibroma: a systematic review and comparison of endoscopic, endoscopic-assisted, and open resection in 1047 cases. Laryngoscope. 2013;123:859–869. Zanation AM, Mitchell CA, Rose AS. Endoscopic skull base techniques for juvenile nasopharyngeal angiofibroma. Otolaryngol Clin North Am. 2012;45:711–730. Woodworth BA, Bhargave GA, Palmer JN, et al. Clinical outcomes of endoscopic and endoscopic-assisted resection of inverted papillomas: a 15-year experience. Am J Rhinol. 2007;21:591–600. Reh DD, Lane AP. The role of endoscopic sinus surgery in the management of sinonasal inverted pa-
pilloma. Curr Opin Otolaryngol Head Neck Surg. 2009;17:6–10. 6. Kim DY, Hong SL, Lee CH, et al. Inverted papilloma of the nasal cavity and paranasal sinuses: a Korean multicenter study. Laryngoscope. 2012;122:487–494. 7. Rawal RB, Gore MR, Harvey RJ, et al. Evidencebased practice: endoscopic skull base resection for malignancy. Otolaryngol Clin North Am. 2012;45: 1127–1142. 8. Batra PS, Lee JT, Barnett SL, et al. Endoscopic skull base surgery practice patterns: Survey of the North American Skull Base Society. Int Forum Allergy Rhinol. 2013;3:659–663. 9. Prevedello DM, Ditzel Filho LF, Solari D, et al. Expanded endonasal approaches to middle cranial fossa and posterior fossa tumors. Neurosurg Clin N Am. 2010;21:621–635. 10. Snyderman CH, Carrau RL, Kassam AB, et al. Endoscopic skull base surgery: principles of en-
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skull base tumor resection. Arch Otolaryngol Head Neck Surg. 2012;138:142–147. 16. Wood JW, Eloy JA, Vivero RJ, et al. Efficacy of transnasal endoscopic resection for malignant anterior skull-base tumors. Int Forum Allergy Rhinol. 2012;2:87–95. 17. Suh JD, Ramakrishnan VR, Chi JJ, et al. Outcomes and complications of endoscopic approaches for malignancies of the paranasal sinuses and ante-
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20. Hanna E, DeMonte F, Ibrahim S, et al. Endoscopic resection of sinonasal cancers with and without craniotomy: oncologic results. Arch Otolaryngol Head Neck Surg. 2009;135: 1219–1224. 21. Harvey RJ, Winder M, Parmar P, Lund V. Endoscopic skull base surgery for sinonasal malignancy. Otolaryngol Clin North Am. 2011;44: 1081–1140.
Practice paerns in endoscopic skull base surgery: survey of the American Rhinologic Society Jivianne T. Lee, MD1,2 , Todd T. Kingdom, MD3 , Timothy L. Smith, MD, MPH4 , Michael Setzen, MD, FACS5,6 , Seth Brown, MD7,8 and Pete S. Batra, MD, FACS9
Background: The introduction of advanced endoscopic techniques has facilitated significant growth in the field of endoscopic skull base surgery (SBS). The purpose of this study is to evaluate the impact of endoscopic SBS on the clinical practice paerns of the American Rhinologic Society (ARS) membership.
observed, with open skull base (32%), unlisted endoscopic (29%), sinus surgery (24%), and unlisted neurosurgical (15%) codes employed by surgeons. Only 29% of physicians reported adequate reimbursement in ≥75% of cases. Eightyfive percent of respondents supported creation of dedicated endoscopic SBS codes.
Methods: A 23-item survey veed by the ARS Board of Directors was electronically disseminated to the ARS membership from February 5, 2013, to March 31, 2013. The target group encompassed 982 ARS members.
Conclusion: This study illustrates the widespread integration of endoscopic SBS procedures into rhinologic clinical practice among survey respondents. However, current variability in coding strategies and inadequate reimbursement may warrant development of specific guidelines to stanC 2013 dardize coding and billing processes in the future.
Results: A total of 152 physicians (15.5%) completed the survey. Open and endoscopic skull base procedures were performed by 41% and 94% of the respondents, respectively. During a typical year, the number of endoscopic skull base cases ranged from 0 to 20 in 56%, 21 to 50 in 26%, 51 to 100 in 9%, and >100 in 8%. Endoscopic cerebrospinal fluid (CSF) leak repair (96%) and transsphenoidal pituitary surgery (81%) were the most commonly performed procedures, followed by transcribriform (68.4%), transplanum (54.4%), and transclival (49.6%) approaches. Overall, 69.6% used endoscopy for resections of malignant sinus/skull base lesions. Considerable variation in Current Procedural Terminology (CPT) coding philosophy was
W
ith continual advances in endoscopic instrumentation and techniques, in recent years we have
1 Department
of Otolaryngology–Head and Neck Surgery, David Geffen School of Medicine at University of California, Los Angeles (UCLA), Los Angeles, CA; 2 Orange County Sinus Institute, Southern California Permanente Medical Group (SCPMG), Irvine, CA; 3 Department of Otolaryngology, University of Colorado, Aurora, CO; 4 Department of Otolaryngology–Head and Neck Surgery, Oregon Health and Science University, Portland, OR; 5 New York University School of Medicine, New York, NY; 6 Department of Otolaryngology, North Shore University Hospital, Manhasset, NY; 7 Division of Otolaryngology, University of Connecticut School of Medicine, Hartford, CT; 8 Connecticut Sinus Institute, Hartford, CT; 9 Department of Otolaryngology–Head and Neck Surgery, University of Texas Southwestern Medical Center, Dallas, TX Correspondence to: Jivianne T. Lee, MD, 6670 Alton Parkway, Irvine, CA 92618; e-mail: [email protected]
ARS-AAOA, LLC.
Key Words: endoscopy; skull base; surgery; data collection; practice paern
How to Cite this Article: Lee JT, Kingdom TT, Smith TL, Setzen M, Brown S, Batra PS. Practice paerns in endoscopic skull base surgery: survey of the American Rhinologic Society. Int Forum Allergy Rhinol. 2014;4:124–131.
witnessed significant expansion, innovation, and evolution in the field of endoscopic skull base surgery (SBS). Although once primarily restricted to management of benign sinonasal and skull base pathology (ie, juvenile nasopharyngeal angiofibroma, inverted papilloma), the spectrum of applications for endoscopic approaches has broadened considerably to encompass progressively larger, more complex lesions as well as anterior skull base malignancies.1–7
Funding sources for the study: Research grant (NIH, National Institute on Deafness and Other Communication Disorders [NIDCD] 2R01 DC005805); Research grants (ARS, Medtronic). Potential conflict of interest: None provided. Received: 12 August 2013; Revised: 22 September 2013; Accepted: 26 September 2013 DOI: 10.1002/alr.21248 View this article online at wileyonlinelibrary.com.
International Forum of Allergy & Rhinology, Vol. 4, No. 2, February 2014
124
Practice patterns, endoscopic skull base surgery
In a recent survey of the North American Skull Base Society (NASBS), endoscopic SBS was performed by 80% (60/75) of respondents, with 32% reporting between 20 and 50 cases in a typical year.8 However, the study mainly targeted practicing skull base surgeons, including otolaryngologists (53%) and neurosurgeons (44%).8 The integration of endoscopic skull base procedures into rhinologic clinical practice has yet to be fully characterized. The purpose of the current survey was to evaluate the impact of endoscopic SBS on the clinical practice patterns of the American Rhinologic Society (ARS) membership. The proportion of surgical practice devoted to SBS and the types of endoscopic skull base approaches most frequently performed was investigated. In addition, economic aspects including Current Procedural Terminology (CPT) coding and reimbursement issues were also assessed. Finally, comparative analysis of data retrieved from the NASBS and ARS surveys was also conducted.
Materials and methods A 23-item written survey exploring endoscopic SBS practice patterns was created and vetted by the ARS Patient Advocacy Committee and Board of Directors. The questionnaire was electronically disseminated to the general ARS membership biweekly from February 5, 2013, to March 31, 2013. The target group encompassed 982 ARS members. Demographic characteristics of the respondents were determined, including geographic location, duration in practice (years), and type of clinical practice (academic, multispecialty, single-specialty group, solo). Geographic regions for the survey were defined as follows: New England (Maine, Vermont, New Hampshire, Massachusetts, Connecticut, Rhode Island), Mid-Atlantic (New York, New Jersey, Pennsylvania), Mountain (Wyoming, Idaho, Montana, Nevada, Utah, Colorado, New Mexico, Arizona), North central (North Dakota, South Dakota, Nebraska, Kansas, Missouri, Iowa, Minnesota, Wisconsin, Illinois, Michigan, Indiana, Ohio), South central (Texas, Oklahoma, Arkansas, Kentucky, Tennessee, Mississippi, Alabama, Louisiana), Southeast (Maryland, Delaware, Virginia, West Virginia, North Carolina, South Carolina, Georgia, Florida), and West coast (Washington, Oregon, California, Alaska, Hawaii). Skull base surgical practice patterns were assessed, including affiliation with a dedicated skull base program, proportion of clinical practice devoted to SBS, and number of open and endoscopic SBS cases performed annually. In addition, use of specific endoscopic skull base techniques was determined, with procedures stratified into cerebrospinal fluid (CSF) rhinorrhea repair and the respective transnasal corridor (transsphenoidal, transcribriform/transethmoid, transplanum, and transclival) approaches. Endoscopic resection of malignant lesions was also evaluated, with respondents asked to report the percentage of sinonasal and skull base malignancies that were managed endoscopically in lieu of open procedures. Finally, socioeconomic aspects
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were examined, such as coding strategies and reimbursement issues. Percentages for each response were calculated based on the number of respondents for each question. Since not all survey respondents answered every question, the response rate per question ranged from 117 to 152. Statistical analysis was performed using Fisher’s exact test to examine significant differences in variables between the 2 groups. SAS version 9.2 (SAS Institute Inc., Cary, NC) was used. A p value 30 years (14, 9.2%). A majority of respondents practiced in an academic setting (84, 55.3%), whereas 43 (28.3%), 14 (9.2%), and 11 (7.2%) were part of single-specialty, multispecialty, or solo practices, respectively. Eighty-three (54.6%) were affiliated with a designated skull base surgery program, and 101 (66.5%) reported working with residents and/or fellows. The percentage of surgical practice devoted to SBS was as follows: 0% to 25% (100, 65.8%), 26% to 50% (21, 13.8%), 51% to 75% (8, 5.3%), and >75% (2, 1.3%). Twenty-one (13.8%) did not perform SBS and were excluded from further analysis. Open and endoscopic skull base procedures were performed by 55 of 136 (40.4%) and 125 of 133 (94%) of the responding surgeons, respectively. An overwhelming majority (124, 91.9%) performed less than 20 open skull base procedures annually, with only 6 (4.4%), 4 (3%), 0 (0%), and 1 (0.7%) physicians completing 21 to 50, 51 to 75, 76 to 100, and >100 cases per year, respectively. In contrast, the number of endoscopic skull base cases was much higher, with 75 (56.4%) performing less than 20 procedures annually, and 35 (26.3%), 5 (3.8%), 7 (5.3%), and 11 (8.3%) physicians completing 21 to 50, 51 to 75, 76 to 100, and >100 cases per year, respectively, as illustrated in Figure 2. Endoscopic CSF leak repair (129, 95.6%) and transsphenoidal pituitary surgery (110, 80.9%) were the most common procedures performed, followed by transcribriform/transethmoid (93, 68.4%), transplanum (74, 54.4%), and transclival (67, 49.6%) approaches. In addition, 94 of 135 (69.6%) physicians used endoscopy in the resection of malignant sinonasal and skull base lesions, with 34 (26.1%) doing so in >75% of cancer cases. Data regarding the number and types of endoscopic SBS procedures performed by responding surgeons are shown in Figure 3. Considerable variation in CPT coding philosophy for endoscopic SBS was observed for the 117 reporting
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FIGURE 1. Geographic location of 152 respondents reported as a percentage of the total number of responses.
FIGURE 2. Range of open and endoscopic skull base procedures performed by respondents in a typical year.
physicians. Open SBS (37, 31.6%), corresponding endoscopic sinus surgery (34, 29.1%), unlisted sinus surgery31299 (29, 24.8%), unlisted neurosurgical-64999 (17, 14.5%), codes were all used, as demonstrated in Figure 4. Coding strategies for nasoseptal flap reconstruction were also variable, with 55 (47%) using secondary dural repair (61619), 20 (17.1%) using unlisted codes, and 19 (16.2%) using a neurovascular pedicle flap (15750) code. However, coding for clinic debridements following endoscopic SBS was fairly consistent, with a majority (86, 69.4%) of participants using 31237. Twenty (16%) respondents did not bill for debridement, whereas 6 (4.8%) and 12 (9.7%) physicians used an unlisted code or 58 modifier, respectively. In terms of reimbursement, 40 (32.8%), 24 (19.7%), 23 (18.9%), and 35 (28.7%) of 122 surgeons felt that com-
pensation was adequate in 0% to 25%, 26% to 50%, 51% to 75%, and >75% of cases, respectively. Overall, 113 of 133 (85%) respondents advocated the creation of new, dedicated endoscopic SBS codes. Univariate analysis (Fisher’s exact test) revealed that type or duration of clinical practice, skull base program affiliation, proportion of surgical practice devoted to SBS, and performance of open or endoscopic SBS had no statistical impact on physician support of new code formation. Only the “percentage of time adequate reimbursement was received” significantly influenced member approval of new codes, with physicians who obtained satisfactory compensation >50% of the time less likely to advocate the development of dedicated endoscopic SBS codes (p = 0.0093) (Table 1).
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FIGURE 3. Percentage of 136 respondents performing each of the respective endoscopic skull base procedures listed in their clinical practice.
FIGURE 4. Coding strategies used by 117 reporting surgeons. CPT = correct procedural terminology.
Comparative analysis of NASBS vs ARS survey data is summarized in Table 2. A statistically greater proportion of NASBS surgeons were found to be affiliated with a skull base surgery program (84% NASBS vs 60% ARS; p = 0.0007), operated in an academic setting (84% NASBS vs 59% ARS; p = 0.0003), performed open SBS (89% NASBS vs 41% ARS; p = 0.0001), and devoted a higher percentage of their surgical practice to skull base procedures (p = 0.0001) in comparison to ARS respondents. Thirty-seven percent of NASBS responders spent >50% of their operative time performing SBS vs 8% of ARS physicians. Similarly, transsphenoidal (95% NASBS vs 81% ARS, p = 0.0086) and transclival (66% NASBS vs 50% ARS, p = 0.0444) approaches were also conducted by a larger number of NASBS survey participants than ARS respondents. However, the number of surgeons performing endoscopic SBS (p = 0.5287), transcribriform (p = 0.868), and transplanum (p = 0.1619) procedures were not statis-
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tically different between the 2 societies. In addition, no significant disparities with respect to CPT coding strategies for SBS were observed (p = 0.937), with an assortment of codes (ie, open SBS, sinus surgery, unlisted endoscopic, unlisted neurosurgical, etc.) used by members of both organizations. Finally, although a lower percentage of NASBS surgeons reported adequate reimbursement >50% of the time compared to ARS responders (31% NASBS vs 48% ARS, p < 0.0001), a statistically equivalent proportion of participants from both surveys (87% NASBS vs 85% ARS; p = 0.8366) advocated the introduction of dedicated endoscopic SBS codes.
Discussion The field of endoscopic SBS has experienced significant growth and development in recent years with the emergence of more advanced endoscopic techniques and
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TABLE 1. Univariate analysis of variables impacting support
TABLE 2. Comparative analysis of NASBS vs ARS data
for new skull base codes Variable Variable
Yes (n = 113)
No (n = 20)
Years of practice
p
0.8087
50%
10 (9)
20 (100)
0.1409
Yes
50 (44)
5 (25)
No
63 (56)
15 (75)
Perform endoscopic skull base surgery 104 (95)
19 (95)
No
6 (5)
1 (5)
Percent of time receiving adequate reimbursement
37 (54) 78 (59)
≥10 years
31 (46) 61 (46)
Academic
57 (84) 78 (59)
Private
11 (16) 55 (41)
Yes
57 (84) 80 (60)
No
11 (16) 53 (40)
5 (26)
>50% of time
44 (43)
14 (74)
0.0001
≤50%
43 (63) 120 (92)
>50%
25 (37)
10 (8) 0.0001
Yes
59 (89) 55 (41)
No
7 (11)
78 (59) 0.5287
Yes
57 (86) 123 (95)
No
9 (14)
Yes No
59 (57)
0.0007
7 (5)
Perform transsphenoidal approaches 0.0093
≤50% of time
0.0003
Perform endoscopic skull base surgery 1.0000
Yes
25% of their operative time to skull base procedures. Endoscopic SBS (84%) was much more commonly performed than open SBS (40.4%). During a typical year, only 4.4% and 3.6% survey participants performed 21 to 50 and >50 open skull bases cases, respectively. In contrast, the number of endoscopic skull base surgeries was much higher, with 26.3% and 17.4% surgeons performing 21 to 50 and >50 cases per year, respectively. The preponderance of endoscopic over open SBS was not unexpected given the demographics of the target group, which was comprised primarily of otolaryngologists with a clinical focus in rhinology as opposed to solely skull base pathology. Of the endoscopic SBS performed, CSF leak repair (95.6%) and transsphenoidal pituitary surgery (80.9%) were the most commonly reported. This is not unexpected because these are well-established procedures with available dedicated codes that do not require the level of surgical expertise essential for more advanced transnasal corridor approaches.12 However, a significant proportion of respondents also implemented more recently introduced endoscopic skull base procedures, including transethmoid/transcribriform (68.4%), transplanum (54.4%), and transclival (49.6%) approaches. In addition, 69.6% also performed endoscopic resection of sinonasal and skull base malignancies. Of the surgeons, 25% and 26.1% employed endoscopic methods over external techniques in 25% to 75% and >75% of cancer cases, respectively. An increasing number of studies in the literature have demonstrated the successful management of malignant skull base lesions us-
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ing transnasal endoscopic procedures with comparable oncologic outcomes to traditional craniofacial resection.13–21 However, concerns regarding long-term survival and the technical feasibility of achieving complete tumor excision with negative margins have deterred some surgeons from pursuing this surgical option. The current survey is unable to ascertain the precise indications or limitations for use of such endoscopic procedures in the treatment of sinonasal and skull base malignancies. Nonetheless, the widespread adoption of endoscopic SBS in the present study exemplifies a paradigm shift among survey respondents in the operative intervention of malignant sinonasal and skull base lesions, with standard open approaches supplanted by less invasive endoscopic techniques. Economic aspects of endoscopic SBS including CPT coding philosophies and reimbursement issues were also investigated by the survey. Marked variability in coding practices was evident, with open SBS (31.6%), corresponding endoscopic sinus surgery (29.1%), unlisted sinus surgery (24.8%), and unlisted neurosurgical (14.5%) codes all used by reporting physicians to document endoscopic skull base procedures. Similarly, with respect to nasoseptal flap reconstruction, multiple codes were employed including secondary dural repair (47%), unlisted (17.1%), and neurovascular pedicle flap (16.2%) codes. Only coding for clinic debridements following endoscopic SBS was fairly uniform, with a majority (69.4%) of respondents using 31237. Given the lack of standardized CPT codes currently available to accurately describe endoscopic SBS, it is not surprising that such significant heterogeneity in coding strategies exist. Although used by the majority of responding surgeons (61%), open skull base and sinus surgery codes do not appropriately represent the services being performed in endoscopic SBS. Unlisted endoscopic and neurosurgical codes likely signify the best alternatives at the present time. However, procuring compensation for unlisted codes can prove challenging, with extensive documentation and onerous discussions with insurance payers often required to facilitate reimbursement. Such obstacles may have accounted for the fewer number of survey participants resorting to unlisted codes for endoscopic SBS in comparison to open and sinus surgery coding options. In the context of such coding ambiguity, only 28.7% surgeons reported receiving adequate reimbursement in >75% of cases; with 85% respondents advocating the creation of dedicated endoscopic SBS codes. Predictably, the only factor that statistically impacted member support for new code formation was the percentage of time satisfactory compensation was obtained, with surgeons who received adequate reimbursement >50% of the time less likely to be proponents for the establishment of new endoscopic SBS codes. However, it should be noted that study results may have been somewhat compromised by potential selection bias of the target group. Because the survey was disseminated to otolaryngologists who, by virtue of their membership within the ARS, had a specialized interest in clinical rhinology, respondents may have been more likely than
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nonrespondents to practice endoscopic SBS. In addition, surgeons who performed endoscopic skull base procedures may have felt more invested in the study outcome and thus been more inclined to accept the initial invitation to participate. Recall bias may also have contributed to an overestimation of the amount of SBS being performed. Therefore, data from the current ARS survey cannot be extrapolated to the general otolaryngology community. Furthermore, it must be emphasized that survey responses signify the opinions of the participating ARS members only and not the viewpoints of the society as a whole. Nevertheless, as a large proportion of respondents (45%) operated in nonacademic settings, study results demonstrated that integration of endoscopic SBS into rhinologic practice was not exclusive to highly-specialized tertiary care centers. In the comparative analysis of survey data from the NASBS vs ARS, both similarities and differences in practice patterns were identified. A statistically greater proportion of NASBS participants worked in an academic setting and were affiliated with a dedicated skull base surgery program. In addition, significantly more NASBS surgeons performed open SBS and devoted a higher percentage of their surgical practice to SBS than their ARS member counterparts. Such discrepancies likely stem from inherent differences in membership constituency between the 2 societies. Whereas the NASBS is comprised of both neurosurgeons and otolaryngologists with a clinical emphasis in SBS, the ARS is exclusive to otolaryngologists with a principal focus in rhinology. Consequently, it is not surprising that NASBS respondents would engage in more SBS clinical activities overall than ARS physicians. However, with respect to the number of surgeons who performed endoscopic SBS, no statistical differences between NASBS and ARS participants were evident, indicating that rhinologic surgeons have also integrated advanced endoscopic skull base techniques into their operative practice. Although a higher percentage of NASBS members were found to perform transsphenoidal and transclival approaches than ARS responders, the proportion of physicians performing transcribriform and transplanum procedures were not statistically dissimilar between the 2 societies.
Similar issues with coding and reimbursement for endoscopic SBS were encountered by members of both organizations. A wide array of coding policies were exhibited, with no significant differences in code distribution between the 2 groups. Although the percentage of NASBS surgeons (69%) claiming inadequate reimbursement was higher than that of ARS responders (52%), aggregate responses of survey participants indicated support of new endoscopic SBS codes irrespective of societal membership. Eight-seven percent of NASBS and 85% ARS survey respondents advocated the introduction of new, dedicated endoscopic SBS codes, highlighting the overwhelming support for pursuit of such an endeavor by member participants from both organizations. Based upon the findings of this survey, it would be prudent to approach the Physician Payment Policy workgroup (3P) of the American Academy of Otolaryngology–Head and Neck Surgery, with the goal of seeking new and appropriate CPT codes for endoscopic SBS.
Conclusion The present study illustrates the widespread integration of endoscopic SBS in rhinologic clinical practice among survey respondents, with 95% affirming incorporation of endoscopic skull base techniques into their surgical armamentarium. Such advanced endoscopic procedures not only encompassed CSF leak repair and transsphenoidal pituitary surgery, but also the more recently described transcribriform, transplanum, and transclival approaches, as well as resections of sinonasal and skull base malignancies. However, current variability in coding strategies and inadequate reimbursement may warrant the development of dedicated endoscopic SBS codes and specific guidelines to facilitate standardization of coding and billing processes in the future.
Acknowledgments We acknowledge Jeff Slezak, PhD, for his statistical support, and Kevin Welch, MD, for coordinating the electronic dissemination of the survey to the ARS membership.
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