RATIONALE FOR THE DEVELOPMENT OF A NOVEL CLINICAL GRADING SCALE FOR POSTOPERATIVE FACIAL NERVE FUNCTION: RESULTS OF A MULTIDISCIPLINARY INTERNATIONAL WORKING GROUP

Dear Editor With great interest, we have read the manuscript by Carlson et al. (1) regarding the development of a novel clinical grading scale (GS) for postoperative facial nerve function. The idea would be that the current House-Brackmann grading scale system is, although most frequently used by the working group, not able to predict postoperative complications focusing mainly on the eye. The new system would lead to the suggestion that “pretty accurate and very simple” is preferable to “very accurate and more complex.” A previously published and widely applied Sunnybrook grading system and the facial nerve grading system MoReSS (2) (Movement, Rest, Secondary defects, and Subjective) are tools to accommodate these wishes. These systems have been suggested in the past to solve the mentioned problems; it has proven its universality and reproducibility with low interobserver variability. Also, it addresses secondary defects of facial nerve dysfunction (such as ophthalmologic problems) and is easy to use. In our University Hospital, since more than a decade, with great proficiency, we apply this MoReSS grading system. After major surgery (such as skull base approaches or oncological parotid surgery), applying this grading system seems not to be the greatest burden to the clinician. Moreover, it is a reliable classification overcoming the main restraints mentioned by the authors. In our view, placing priority on simplicity is a step back in patient care. (3) As Fattah et al. (3)—on behalf of the Sir Charles Bell Society—stated, the ideal characteristics of a grading scale would be to provide regional scoring. Also to perform static and dynamic measurements and examine secondary sequelae. Lastly reproducible results sensitive to track changes over time are provided, following interventions making the scale convenient to use. As most patients with a facial nerve palsy have a nonsurgical etiology, it might be wise to make assessment for this group the most important task. If a scale can reliably be used for Bell's palsy, it might be good as well for postoperative facial nerve outcome. The authors anticipated that a newly developed system would be used to assess acute nonsurgical facial nerve injury. At this point, we disagree with the authors, because the newly developed grading system that is proposed does not fit the Fattah criteria (3) accurately enough. Simplification of a scale might be feasible such as the House-Brackmann in grade 1 = normal, 2 = almost normal, 3 = paresis, eye can be closed, 4 = paresis, eye cannot be closed, 5 = almost complete paralysis, 6 = complete paralysis. However, this will be of little or no reliable use in measuring treatment outcome in practice or research communications. We do not think that such simplicity will improve patient care in the end. The authors describe a couple of suggestions for a new scale, of which most discriminate two regions of the face only. Whereas in the past most innovative scales were invented to improve accuracy, this newly presented scale will likely improve simplicity but will not be superior in conveying important information. The newly supposed system is certainly not accurate for determining the complex facial nerve function or deficit. We fear that with less accurate grading systems, the discussion about appropriate medical (steroids, antiviral) or surgical (nerve decompression or anastomoses) treatment outcome will suffer from simplifications and not likely resolve the discussion how to follow-up on facial palsy. The Multidisciplinary International Working Group (1) states that the methodology should be easy to learn and recall. We suggest to use an accurate and reliable form (digital computer or a paper version). There seems to be a discrepancy regarding ratings done by the professional (medical team) and the patient. Itmight be that these ratings are prone to subjectivity and therefore medical professional as well as patient interpretation of facial nerve function should be mentioned.Therefore, we think that it is important to have at least some idea of subjective grading by patients themselves. Kahn et al. already noted this as important in 2001. With an accurate description of the complex facial nerve function, transparency in communicating is primordial. Future reports will then be able to indicate and discuss the points of interobserver variability, which will occur with most grading scales, for individual patients in a more meaningful manner. Henricus Geert Xavier Maria Thomeer Department of Otorhinolaryngology— Head and Neck Surgery University Medical Centre Utrecht Utrecht the Netherlands Brain Center University Medical Centre Utrecht the Netherlands [email protected]Jacob de Ru Department of Otorhinolaryngology-Head and Neck Surgery University Medical Centre Utrecht Utrecht the Netherlands