Objective and Subjective Outcomes in Surgery for Chronic Sinusitis
Endoscopic and radiological findings in patients with chronic sinusitis do not always correlate with symptoms. Studies suggest that postoperative endoscopic examination of the sinonasal cavity provides prognostic information regarding the potential for future episodes of sinusitis and the need for revision surgery. It is recommended that findings on nasal endoscopy be included in future outcomes studies on sinusitis.
The advent of endoscopic instrumentation has revolutionized the way in which otolaryngologists manage sinus disease, in particular, chronic sinusitis. Endoscopy permits accurate diagnosis of the nasal manifestations of sinus disease by revealing findings easily missed with anterior rhinoscopy, 1,2 as well as permitting directed cultures of the middle meatus and other areas of the nasal cavity. 3 Equally important, the use of rigid endoscopes makes possible meticulous postoperative care and close, detailed follow-up. This detailed follow-up is possible because, after endoscopic sinus surgery (ESS), the marsupialized sinus cavities are readily accessible to direct inspection by the endoscope, thus allowing an objective measure of surgical and medical treatment. Such observation permits detection of changes in the sinonasal mucosa that indicate ongoing or recurrent inflammation, video or photographic recording of persistent changes, and direct endoscopic evaluation of such changes over time.
CORRELATION OF OBJECTIVE AND SUBJECTIVE OUTCOMES MEASURES
The long-term natural history of chronic sinusitis after treatment has been documented. Late development of recurrent symptomatology and complications after many years has been reported by several authors and has led to the demise of many of the earlier surgical approaches, after initial enthusiasm in the literature. In several instances, these late recurrences and complications have quietly caused a particular approach to fall into disfavor. However, some authors have published long-term series demonstrating the problem of late symptomatic recurrence. Neel 4 noted that failure of the Lynch procedure for frontal sinusitis occurs in 7% of patients at 3.7 years and 30% at 7 years. Montgomery 5 noted recurrent frontal sinusitis up to 43 years after treatment that appeared to be initially effective. Therefore it seems that the symptoms of chronic sinusitis may be initially controlled by surgery, but symptomatic disease can recur, even many years later, necessitating additional treatment and even additional surgery.
Few studies have examined the objective outcomes after ESS, and fewer yet have compared the objective outcomes (endoscopic or computed tomography [CT] findings, or both) with subjective outcomes (patient self-reported symptoms). Vleming and de Vries 6 published their results of 165 patients operated on over a 2-year period with an average follow-up of 10 months. Subjective results, based on patient response to a questionnaire, were reported to be good in 51%, moderate in 22%, and poor in 27%. The researchers combined the data for good and moderate outcomes into a category that they termed “improved,” which totaled 73% overall. Their objective findings, based on endoscopic evaluation of the sinus cavities (absence of synechiae, recurrent polyps, and hyperplastic mucosa), were reported as good in 73% of cases. When these authors correlated results with preoperative indications for surgery, they found that patients with polyposis tended to have a better subjective outcome (90% improved) than those without polyposis (76% improved). However, when the objective results were examined, 52% of patients with polyposis were found to have subjective improvement but had an objectively poor result. The re-searchers concluded that long-term follow-up is necessary in patients with polyposis, since mucosal abnormalities continue even after symptomatic improvement has occurred. Inherent in this conclusion is that this persistence of mucosal changes in the sinus cavity is probably a harbinger of recurrent symptomatic chronic sinusitis.
Vleming et al. 7 published another report on subjective and objective findings in 182 patients undergoing surgery for chronic sinusitis with 46 months of follow-up. In patients with chronic or recurrent sinusitis, subjective improvement was seen in 85%, and objective improvement in 77%. The results in their patients with polyposis were reported as 90% subjective improvement and only 65% objective improvement with an average follow-up of 24 months. Patients with persistent mucosal abnormalities were often asymptomatic for the duration of the follow-up period.
Taken together, the results of such studies support the statement that symptom improvement does not always correlate with resolution of mucosal abnormalities as determined by nasal endoscopy. Patients who demonstrate an abnormal appearance of the sinus cavities after surgery may have a higher incidence of recurrent symptoms in the future when compared with patients whose examination does not demonstrate mucosal abnormalities. This study was undertaken to help determine whether an abnormal appearance of sinus cavities on nasal endoscopy was associated with the subsequent need for surgery for recurrent chronic sinusitis.
THE KENNEDY STUDIES ON SUBJECTIVE AND OBJECTIVE OUTCOMES
Kennedy 8 followed 56 surgical patients prospectively from April 1989 to May 1990. Seventy additional patients were enrolled retrospectively as they presented during this same time interval for postoperative follow-up. Of these 126 patients, 120 were evaluated by both a questionnaire and nasal endoscopy with a mean follow-up of 18 months following surgery. To evaluate for bias in the patients enrolled retrospectively at the time of follow-up, an additional 150 randomly selected patients were mailed follow-up questionnaires; 58% were returned. No variance was noted in the results from the patients included in the study. In all, 240 fields of information were collected for the study patients, including subjective perception of improvement and potential contributing factors such as allergy, polyps, asthma, and previous surgery. Endoscopic appearances of the sinus cavities were noted with specific attention to the nasal cavity, ethmoid sinuses, maxillary sinus, sphenoid sinus, and frontal recess. Questionnaires were later mailed to this same group of patients at a mean time of 7.8 years after surgery, and the results were subsequently reported.
By nature of the tertiary care practice, the patients in general would be considered to have severe and recalcitrant disease. Seventy-one percent of the patients in the study had a history of prior nasal or sinus surgery. Forty-nine percent had had at least one prior ethmoidectomy, and the maximum number of procedures in an individual patient was 13.
At 18 months after surgery it was found that the subjective improvement noted by most patients was entirely independent of preoperative CT stage. The endoscopic findings at 18 months were largely independent of allergy, aspirin sensitivity, prior surgery, asthma, and allergic fungal sinusitis when staged for extent of preoperative disease, although patients with asthma and severe sinonasal polyposis did objectively less well than patients with similarly staged disease without asthma. The primary factor that correlated with endoscopic postoperative findings was the initial CT stage. Subjective postoperative improvement, on the other hand, did not correlate with preoperative CT stage and did not correlate with endoscopic findings at 18 months. Essentially, patients were overwhelmingly improved at 18 months, despite the extent of preoperative disease severity.
When questionnaires were remailed to patients at a mean time of 7.8 years after surgery, 72 of the original patients responded to the mailed questionnaire. 9 The aim of this study was to determine the subjective status of these patients and whether patients with persistent endoscopic evidence of inflammation in the postoperative period (mean duration, 18 months) were more likely to have symptomatic recurrence and require surgical intervention. Data analysis demonstrated that 98.4% of respondents reported continued subjective improvement at a mean time of 7.8 years compared with preoperative symptoms. Asthma and antibiotic medication usage were reduced, but 18% of patients had required revision surgery. A trend toward continued improvement in specific symptoms such as headache, nasal discharge, and recurrent infections occurred over the prolonged follow-up, but was not statistically significant.
A more detailed analysis of the patients requiring revision surgery was performed in an attempt to identify factors that were present at 18 months which were predictive of the need for revision surgery. Because of the small sample size, few features could be identified that reached statistical significance, although some trends were seen. A trend toward an increased need for revision endoscopic surgery was present in patients with greater disease on preoperative CT staging. Detailed endoscopic examination had been performed on all patients at 18 months, noting evidence of discharge, inflammation, mucosal hypertrophy, scarring, crusting, or polyps in five specific areas of the sinonasal cavity. Patients not requiring revision surgical intervention were statistically more likely to have had a normal cavity on endoscopic examination at that point in time, and no patients who had had normal or near-normal cavities on endoscopic examination at 1.5 years after surgery required subsequent surgery. On the other hand, symptomatic results at 1.5 years were not predictive of the need for subsequent surgical intervention. An additional issue identified was that, although no smokers were present in the patients who did not have revision, all smokers with advanced disease at the time of the initial surgery who continued to smoke required surgical revision.
The conclusion drawn was that excellent subjective results could be routinely obtained after ESS, provided that patients received appropriate postoperative care. Appropriate postoperative care in this study was defined as meticulous inspection and aggressive debridement and medical therapy. Patients whose cavities became normal on endoscopic inspection after surgery and postoperative care were much less likely to require revision surgery. The data demonstrated a significant correlation between the endoscopic persistence of mucosal abnormalities at 18-month follow-up and the need for subsequent revision surgery.
VALIDATED AND RECOMMENDED OUTCOMES MEASURES
In recent years there has been a concerted effort to evaluate subjective outcomes after treatment of chronic sinusitis. Primarily this has involved subjective rating scales that have been classified into general health status instruments and disease-specific instruments. A commonly used general health evaluation tool is the Medical Outcomes Study Short Form-36 (SF-36). 10 Although not specifically designed for sinusitis, this evaluation tool provides information concerning the functional well-being of the individual and the evaluation of the overall response to treatment.
For the evaluation of the subjective effects of chronic sinusitis and response to therapy, several tools have been developed. Examples of these disease-specific tools include the Chronic Sinusitis Survey (CSS), which was developed at the Massachusetts Eye and Ear Infirmary, 11 as well as the Chronic Sinusitis TyPE (Technology of Patient Experience) Specific Questionnaire developed by the Health Outcomes Institute. 12 Both of these systems serve to monitor both patient symptoms and requirement for medical therapy over the previous 8-week period (i.e., they are duration based). Both of these forms have been accepted as being reliable and sensitive to clinical change over time. They are both simple and easy to use and provide information over time regarding the efficacy of a therapeutic intervention. The TyPE Specific Questionnaire has been recommended by the American Academy of Otolaryngology—Head and Neck Surgery (AAO-HNS) Rhinosinusitis Task Force for thorough evaluation. 13
In the recent report of the AAO-HNS Rhinosinusitis Task Force, the modified Lund-MacKay staging system was recommended for widespread use for the validation of outcomes in large clinical studies. 14 This system incorporates subjective symptom review, CT scan results, and surgical findings to evaluate and quantify patients with chronic sinusitis. As part of the ongoing evaluation, patient symptom scores (based on a visual analogue scale) are recorded preoperatively and at 3, 6, 12, and 24 months postoperatively. It was proposed that the endoscopic appearance of the sinus cavity be recorded at these same time intervals. While the endoscopic appearance of the sinus cavity is not included in the formal staging system, its inclusion by the AAO-HNS Rhinosinusitis Task Force clearly reflects recognition of the importance of objective assessment of sinus cavities postoperatively. 14
Symptom improvement in rhinosinusitis does not correlate with endoscopic resolution of mucosal abnormalities or preoperative CT stage. Conversely, endoscopic resolution of disease at 18 months after surgery correlated with the absence of the need for further surgery.
There is strong evidence that endoscopic examination of the sinonasal cavity postoperatively provides prognostic information concerning the potential for subsequent development of symptomatic chronic sinusitis. This information is independent of the subjective reporting of symptoms by patients at 18-month follow-up. Therefore, in addition to the subjective survey of patient symptoms, it is recommended that nasal endoscopy be included in outcomes studies of chronic sinusitis as a direct, easily available, and predictive measure following surgery.
Although implied by the study, further evaluation of patients with chronic sinusitis is warranted to determine whether aggressive treatment of mucosal changes in the early (18-month) postoperative period, before the development of overt symptoms, may avert the need for subsequent revision surgical intervention and otherwise have an impact on treatment outcome.