Abstract
Dear Editor:
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We believe that the design of the study and, more importantly, the subset analysis of the study population help to eliminate some of the concerns brought up. Dr. Douglas only chooses to recognize the limitations or weaknesses of prospectively collected longitudinal study designs with complete data capture. Unfortunately, she omits the strengths of such a design, including usefulness in accurately assessing patient growth and development, identifying and measuring within-patient relationships, and making reliable inferences of treatment effect over time. Although we acknowledge that the Breastfeeding Self-Efficacy Scale - Short Form (BSES-SF) has been shown to improve over time without intervention, we feel that the inclusion of the 1 week time point eliminates the impact of natural improvement. To assume that an entire cohort naturally improves coincidentally 1 week after surgical intervention is specious. In addition, to assume that natural progression would account for the improvement in the older babies in the study, both the 5–8-week olds and the 9–12-week olds, seems even more unlikely given the absence of natural improvement before inclusion in the study.
The authors want to reiterate that all babies underwent independent International Board Certified Lactation Consultant (IBCLC) evaluation before inclusion in the study. Because previous studies have demonstrated that the delay of surgical intervention puts the nursing relationship at risk, the authors feel that it is important to balance conservative IBCLC evaluation and intervention with surgical release of tethered tissue.3,4 This is especially important as the child gets older, whereby intervention by the IBCLC has not achieved clinical improvement in the time leading up to inclusion in the study. Furthermore, previous studies addressing posterior tongue tie have already demonstrated clinical improvement after surgical release.5,6 Although we agree that a randomized controlled clinical trial would be ideal to conduct, communication with the Institutional Review Board indicated that such a trial would be unlikely to be approved by the ethics board given the risks posed to mothers and babies by withholding surgical intervention.
The concerns brought up specifically with our use of the i-GERQ-r-validated questionnaire are misplaced. Dr. Douglas writes that parents are unable to avoid the placebo effect when grading infant behavior, suggesting this invalidates the use of the i-GERQ-r tool. Unfortunately, the study she cites as evidence showing that the i-GERQ-r tool is invalid does not actually use the i-GERQ-r to grade infant behavior. 7 The Partty study evaluates a small cohort (only 30 infants) and evaluates only behaviors of crying—no mention of the i-GERQ-r is made. It is important to recognize that the i-GERQ-r is a validated tool with numerous, specific signs and symptoms associated with reflux. Although it is not a substitute for barium imaging or endoscopy, it is recognized as the best valid tool to evaluate these symptoms without performing an invasive procedure. A lack of previous documentation of aerophagia in no way invalidates novel findings demonstrating the clinical improvement in these patients. However, others recently have described improvement in aerophagia-induced reflux after frenotomy. 8 The authors point out that aerophagia would not be adequately assessed on submental breastfeeding ultrasound and in fact was not assessed in the ultrasound study cited. 9 The ultrasound study does, however, corroborate our findings of improvement in milk transfer and decrease in maternal pain after complete frenotomy. Finally, an excellent meta-analysis by Ito found no major complications in infants undergoing frenotomy. 10
With respect to milk transfer efficiency, the natural improvement in milk intake in the Sakalidis study is cited to invalidate what is demonstrated in our subset of patients. Unfortunately, there is little that can be compared between the two studies. The Sakalidis study examined 3-day-old infants and then reevaluated those babies around 3 weeks of age. 11 Our study evaluates a mixed age population (almost all older than 3 days) and reevaluates the milk intake at 1 week postprocedure. Once again, we feel that both the shorter interval and the inclusion of older babies in our subset analysis allow us to attribute the improvement in milk intake to the procedure and not simply to the passage of time. The Sakalidis study's focus on 3-day-olds as a baseline skews the magnitude of natural progression as most breastfeeding clinicians would argue that the very young child often demonstrates more issues with milk transfer than the older child.
Ultimately, we acknowledge that much of breastfeeding research is tainted by the potential for placebo effect and bias. We believe that the use of tools measuring specific outcomes, validated tools for evaluating tongue tie, and short follow-up intervals allows clinicians an opportunity to judge whether the results are attributable to the intervention performed. There is likely some bias present in how each clinician approaches tongue tie's effect on breastfeeding—many view it as a “hot button” issue, questioning the legitimacy of the diagnosis and interventions addressing ankyloglossia. Dr. Douglas has previously written on the need to rethink posterior tongue tie 12 —the authors point out that posterior tongue tie release mistakenly has the perception of a “deep” cut or release, whereas, in fact, the depth of the release is mucosal in depth (∼1 mm). This misconception (demonstrated in the Douglas article) regarding technical details of the surgical procedure itself may account for some of Dr. Douglas's concerns—the authors feel that the language referring to tongue tie as “anterior” or “posterior” is an arbitrary dichotomy and may have untoward effects. Instead, we put forth that all tongue tie releases should be done completely, which includes posterior fibers, for optimal results.
We look forward to any original research that Dr. Douglas may publish that can address the concerns she brings up in her letter, as we agree that part of good 21st century science includes accepting research that may contradict established paradigms.