Brandel Michael G, Dalle Ore Cecilia L, Reid Chris M, Zhang Wendy W, Zhu William, Kpaduwa Chinwe S, Lance Samuel, Meltzer Hal S, Gosman Amanda A
Ann Plast Surg. 2018 May;80(5S Suppl 5):S251-S256. doi: 10.1097/SAP.0000000000001381.
Methods of reporting quantitative results for distraction osteogenesis (DO) of craniosynostosis have been inconsistent. Therefore, the efficacy of differing techniques and timing in regard to volume change is not well established, with no uniform metric for comparisons. Given that cranial vault remodeling with DO may be completed with different approaches, analysis was made to determine (1) the relative efficiency of different approaches in expanding intracranial volume (ICV) and (2) the impact of adjusting for ICV growth on measured DO efficiency.
Patients with craniosynostosis were treated with open cranial vault reconstruction combined with internal distraction. Preoperative and postoperative computed tomography scans were used to quantify ICV change. The metric was determined by dividing percent ICV change by total distraction length. The metric was used as a proxy for efficiency to compare posterior and anterior distraction between groups using the Mann-Whitney U test and within a subgroup of patients who underwent 2-stage distraction using the Wilcoxon matched-pairs signed rank test.
Twenty patients underwent cranial vault remodeling with DO: 14 unicoronal, 3 bicoronal, 2 multisutural, and 1 lambdoid. Results are reported in medians. Distraction efficiency was 0.99%/mm for primary anterior, unilateral distraction for unicoronal patients (n = 13, aged 9.1 months) and 4.28%/mm for posterior distraction using multiple distractors (n = 4, aged 6.3 months). In terms of the metric, primary posterior distraction was significantly more efficient than primary anterior distraction (P = 0.007). Three patients who had undergone primary posterior distraction later underwent secondary anterior distraction. Again, posterior distraction was shown to be significantly more efficient (5.16 vs 0.62, P = 0.050). For the unicoronal patients who received anterior unilateral distraction, an adjusted metric was calculated to account for normal intracranial growth. This was found to be 0.39%/mm, which was significantly different from the unadjusted metric (P = 0.0001).
Posterior distraction is more efficient for ICV expansion than anterior distraction, which may have implications for the choice of approach for craniosynostosis repair. In addition, this is the first report of a novel standardized metric for analyzing ICV change achieved by DO. This tool allows for adjusting the efficiency metric for expected ICV growth, which significantly impacts its value.
颅骨缝早闭牵张成骨（DO）定量结果的报告方法一直不一致。因此，不同技术和时间安排在体积变化方面的疗效尚未明确，缺乏统一的比较指标。鉴于颅骨穹窿通过DO重塑可能采用不同方法完成，本分析旨在确定：（1）不同方法在扩大颅内体积（ICV）方面的相对效率；（2）调整ICV生长对测量的DO效率的影响。
颅骨缝早闭患者接受开放性颅骨穹窿重建联合内牵张治疗。术前和术后计算机断层扫描用于量化ICV变化。该指标通过将ICV变化百分比除以总牵张长度来确定。该指标用作效率的替代指标，使用曼-惠特尼U检验比较组间前后牵张情况，并在接受两阶段牵张的患者亚组中使用威尔科克森配对符号秩检验。
20例患者接受了颅骨穹窿DO重塑：单冠状缝14例，双冠状缝3例，多缝型2例，人字缝1例。结果以中位数报告。单冠状缝患者（n = 13，年龄9.1个月）原发性前路单侧牵张的牵张效率为0.99%/mm，使用多个牵张器的后路牵张效率为4.28%/mm（n = 4，年龄6.3个月）。就该指标而言，原发性后路牵张明显比原发性前路牵张更有效（P = 0.007）。3例接受原发性后路牵张的患者后来接受了继发性前路牵张。同样，后路牵张显示出明显更高的效率（5.16对0.62，P = 0.050）。对于接受前路单侧牵张的单冠状缝患者，计算了调整后的指标以考虑正常颅内生长。结果为0.39%/mm，与未调整的指标有显著差异（P = 0.0001）。
后路牵张在扩大ICV方面比前路牵张更有效，这可能对颅骨缝早闭修复方法的选择有影响。此外，这是首次报告一种用于分析DO实现的ICV变化的新型标准化指标。该工具允许针对预期的ICV生长调整效率指标，这对其值有显著影响。
