Importance: Tonsil size assessment on physical examination is often used as a key component of clinical decision-making, specifically in estimating the success or failure of adenotonsillectomy surgery. The accuracy of this approach is not specifically known.
Objective: To systematically review the biomedical literature for data comparing subjective preoperative tonsil (and adenoid) size (0- to >4-point scale) with adenotonsillectomy outcomes using polysomnography and/or quality of life outcomes.
Evidence review: A PubMed and Embase search was conducted from June 1, 2018, through November 1, 2018, to identify articles comparing preoperative subjective tonsil and adenoid size with surgical outcomes. Key search terms included adenotonsillectomy, tonsil size, Brodsky scale, apnea-hypopnea index, OSA-18, polysomnography, and quality of life, with limits of 0 to 18 years of age. Inclusion criteria included articles on pediatric patients only, articles on patients who underwent tonsillectomy or adenotonsillectomy, and articles that included presurgical and postsurgical data. Exclusion criteria included patients who received surgery beyond adenotonsillectomy and studies that did not compare tonsil and adenoid size grades with surgical outcomes.
Findings: A total of 27 studies were included in the final data set. The mean sample size was 79.7 (range, 17-250), and the mean age was 6.3 years (range, 4.2-12.8 years). Case series was the predominant study design (20 studies). Fourteen studies specifically excluded obesity and craniofacial syndromes, whereas 2 studies addressed patients with trisomy 21 only, and 5 studies focused on patients with obesity. Outcome measures included polysomnography (19 studies), Obstructive Sleep Apnea 18 survey (4 studies), Obstructive Sleep Apnea 6 (1 study), oxygen desaturation index (1 study), and overnight pulse oximetry (1 study). Ten studies conducted postoperative evaluations within 90 days of the intervention, and 17 studies had greater than 90-day follow-up. A total of 22 of the 27 studies (81.5%) concluded that there was no association between tonsil and adenoid size and surgical outcome, whereas 5 studies (18.5%) concluded that there was an association. Studies that found no association had a higher mean quality score than those that found an association (15.6 vs 14.5; difference in means, 1.13; 95% CI, 0.07-2.19).
Conclusions and relevance: Most published clinical evidence suggests that subjective tonsil and adenoid size is not reliably associated with adenotonsillectomy success or failure because success rates are typically high regardless of tonsil size. Physicians should understand the potential limitations of using tonsil size alone as the key component of clinical decision-making for adenotonsillectomy.