Purpose: Our aim was to evaluate the effect of a vacuum bell (VB) combined with a three-dimensional (3D) scanner for the noninvasive treatment of pectus excavatum (PE).
Methods: A VB was used to create a vacuum at the anterior chest wall with a patient-activated hand pump, and it should be applied regularly for more than 2 h each day at home. Eighty-two patients required to be followed up every three months were included in this retrospective study and distributed into four stages (stage 1: treated for 3 months, stage 2: treated for 6 months, stage 3: treated for 9 months, and stage 4: treated for 12 months). In addition, the deformity in the chest wall was scanned by a 3D scanner at the clinic, and the 3D depth (3D-DE) and 3D Haller index (3D-HI) of PE were calculated through Geomagic studio 2013 software.
Results: Eighty-two patients (12/2017-12/2019) met the criteria at the clinic, and 24 patients (29.3%) achieved excellent correction (3D-DE ≤ 3 mm). When comparing the improvement in 3D-DE and 3D-HI of PE to the patient's treatment time, a statistically significant difference was observed between stages 2 and 1 (3D-DE p < 0.01, 3D-HI p < 0.01), stages 3 and 2 (3D-DE p < 0.01, 3D-HI p < 0.01) and stages 4 and 3 (3D-DE p < 0.01, 3D-HI p < 0.01). There was a statistically significant difference in sternum elevation between patients aged < 10 years and those aged ≥ 10 years (3D-DE p = 0.006, 3D-HI p = 0.045) and patients with symmetrical and asymmetric PE (3D-DE p = 0.042, 3D-HI p = 0.032). However, there was no statistically significant difference in sternal elevation between males and females (3D-DE p = 0.27, 3D-HI p = 0.495). The main side effects were moderate subcutaneous hematoma, petechial bleeding, thoracalgia and chest tightness.
Conclusions: With controllable side effects, noninvasive treatment for PE with a VB combined with a 3D scanner is safe, objective and radiation free, and the initial results to date are encouraging. Patients aged < 10 years, with symmetrical PE and treated for over 12 months may achieve a better outcome.
Keywords: 3D scanner; Pectus excavatum; Radiation-free; Vacuum bell (VB).