Strahle Jennifer M, Taiwo Rukayat, Averill Christine, Torner James, Gewirtz Jordan I, Shannon Chevis N, Bonfield Christopher M, Tuite Gerald F, Bethel-Anderson Tammy, Anderson Richard C E, Kelly Michael P, Shimony Joshua S, Dacey Ralph G, Smyth Matthew D, Park Tae Sung, Limbrick David D
1Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri.
2Department of Epidemiology, University of Iowa, Iowa City, Iowa.
J Neurosurg Pediatr. 2020 Apr 10;26(1):53-59. doi: 10.3171/2020.1.PEDS18755. Print 2020 Jul 1.
In patients with Chiari malformation type I (CM-I) and a syrinx who also have scoliosis, clinical and radiological predictors of curve regression after posterior fossa decompression are not well known. Prior reports indicate that age younger than 10 years and a curve magnitude < 35° are favorable predictors of curve regression following surgery. The aim of this study was to determine baseline radiological factors, including craniocervical junction alignment, that might predict curve stability or improvement after posterior fossa decompression.
A large multicenter retrospective and prospective registry of pediatric patients with CM-I (tonsils ≥ 5 mm below the foramen magnum) and a syrinx (≥ 3 mm in width) was reviewed for clinical and radiological characteristics of CM-I, syrinx, and scoliosis (coronal curve ≥ 10°) in patients who underwent posterior fossa decompression and who also had follow-up imaging.
Of 825 patients with CM-I and a syrinx, 251 (30.4%) were noted to have scoliosis present at the time of diagnosis. Forty-one (16.3%) of these patients underwent posterior fossa decompression and had follow-up imaging to assess for scoliosis. Twenty-three patients (56%) were female, the mean age at time of CM-I decompression was 10.0 years, and the mean follow-up duration was 1.3 years. Nine patients (22%) had stable curves, 16 (39%) showed improvement (> 5°), and 16 (39%) displayed curve progression (> 5°) during the follow-up period. Younger age at the time of decompression was associated with improvement in curve magnitude; for those with curves of ≤ 35°, 17% of patients younger than 10 years of age had curve progression compared with 64% of those 10 years of age or older (p = 0.008). There was no difference by age for those with curves > 35°. Tonsil position, baseline syrinx dimensions, and change in syrinx size were not associated with the change in curve magnitude. There was no difference in progression after surgery in patients who were also treated with a brace compared to those who were not treated with a brace for scoliosis.
In this cohort of patients with CM-I, a syrinx, and scoliosis, younger age at the time of decompression was associated with improvement in curve magnitude following surgery, especially in patients younger than 10 years of age with curves of ≤ 35°. Baseline tonsil position, syrinx dimensions, frontooccipital horn ratio, and craniocervical junction morphology were not associated with changes in curve magnitude after surgery.
在患有I型Chiari畸形（CM-I）且伴有脊髓空洞症及脊柱侧弯的患者中，后颅窝减压术后脊柱侧弯曲线回归的临床和放射学预测因素尚不清楚。既往报告表明，年龄小于10岁且侧弯角度<35°是术后侧弯曲线回归的有利预测因素。本研究的目的是确定包括颅颈交界区对线情况在内的基线放射学因素，这些因素可能预测后颅窝减压术后脊柱侧弯曲线的稳定性或改善情况。
回顾一项大型多中心回顾性和前瞻性登记研究，该研究纳入了患有CM-I（扁桃体低于枕骨大孔≥5mm）和脊髓空洞症（宽度≥3mm）的儿科患者，以分析接受后颅窝减压且有随访影像学检查的患者的CM-I、脊髓空洞症和脊柱侧弯（冠状面曲线≥10°）的临床和放射学特征。
在825例患有CM-I和脊髓空洞症的患者中，251例（30.4%）在诊断时被发现存在脊柱侧弯。其中41例（16.3%）患者接受了后颅窝减压并进行了随访影像学检查以评估脊柱侧弯情况。23例患者（56%）为女性，CM-I减压时的平均年龄为10.0岁，平均随访时间为1.3年。9例患者（22%）的脊柱侧弯曲线稳定，16例（39%）显示改善（>5°），16例（39%）在随访期间脊柱侧弯曲线进展（>5°）。减压时年龄较小与侧弯角度改善相关；对于侧弯角度≤35°的患者，年龄小于10岁的患者中17%出现侧弯曲线进展，而10岁及以上患者中这一比例为64%（p=0.008）。侧弯角度>35°的患者在年龄方面无差异。扁桃体位置、基线脊髓空洞症大小及脊髓空洞症大小变化与侧弯角度变化无关。与未使用支具治疗脊柱侧弯的患者相比，使用支具治疗的患者术后进展情况无差异。
在这组患有CM-I、脊髓空洞症和脊柱侧弯的患者中，减压时年龄较小与术后侧弯角度改善相关，尤其是对于年龄小于10岁且侧弯角度≤35°的患者。基线扁桃体位置、脊髓空洞症大小、额枕角比值和颅颈交界区形态与术后侧弯角度变化无关。
