CDE is characterized by incomplete muscle regeneration. Subsequent abnormally elevated diaphragm muscles cause abnormal movement of the affected hemidiaphragm during respiration. It can occur locally or affect the entire diaphragm. In this study, there were 90 males (72%) and 35 females (28%); 78 children (62.4%) had CDE on the right side, and 47 children (37.6%) had CDE on the left side. We observed that the incidence was higher in male children, and the incidence on the right side was higher than that on the left side. CDE can be associated with other developmental defects, and associated comorbidities include congenital hypoplastic lung, congenital heart disease, pectus excavatum, cleft palate, hypospadias, cryptorchidism, and congenital torticollis[4]. Seventy-seven patients in this group also had other malformations, and congenital heart disease (19, 15.2%) and congenital hypoplastic lung (16, 12.8%) were the main relevant abnormalities in this study. The above facts make it difficult to determine whether CDE is accompanied by other malformations or other malformations with this disease. Its numerous accompanying malformations suggest that the cause of teratology is difficult to explain with a single etiology and may be similar to the cause of other congenital malformations.
The main symptom of CDE is compression of the lower lobe of the lungs due to the increase in intra-abdominal organs. Compression can also cause the mediastinum to move on the healthy side, and the lung function of the healthy side can be reduced accordingly. In unilateral CDE, the lung capacity and total lung capacity are reduced by 20% - 30%[5]. Bilateral diaphragmatic eventration reduces lung function even more seriously, especially in the supine position[6]. The treatment principle of CDE is to restore the normal anatomical position and tension of the diaphragm. The method is to strengthen the weak diaphragm, and the goal is to maintain normal lung volume and lung ventilation. Whether asymptomatic patients need surgical correction has been controversial for a long time. In this group of 17 children who did not undergo surgical treatment, 11 patients received 1-6 years of follow-up, and a decrease in diaphragm position was not observed. Therefore, we believe that symptomatic children need timely surgical treatment. Yazici M et al.'s study also considered symptomatic children, who usually require surgery [7]. Therefore, we believe that the indications for surgery are as follows: ① relative to the normal diaphragm position, the diaphragm is displaced upwards by 3 or more intercostals; ② diaphragm eventration causes obvious compression on the affected side of the lung and obvious shortness of breath, asthma and other respiratory distress symptoms; ③ frequent lung infections, hypoxemia, and even abnormal breathing exercises; and ④ during follow-up, the diaphragm continues to rise, and the eventration is aggravated.
The traditional treatment method of CDE is diaphragmatic plication performed either by laparotomy or thoracotomy. However, with the development of minimally invasive technology, thoracoscopy has gradually been applied in the treatment of CDE [8-10]. We believe that children with right diaphragm eventration and intrapulmonary malformation need to be corrected through the thoracotomy approach as the first choice because it is not affected by the intestinal canal, there is full exposure, there operation is easy, the phrenic nerve can be visualized, and postoperative intestinal paralysis can be reduced. Laparotomy is suitable for children with left diaphragmatic eventration, in cases where it is not possible to distinguish diaphragmatic eventration from diaphragmatic hernia, and when gastrointestinal malformation is considered. Because the heart is in the left chest, there is a high risk associated with thoracotomy. The use of a subcostal incision is conducive to hernia repair and the discovery of possible intestinal malformations. However, in the open group, we used thoracotomy in 4 children with diaphragmatic eventration on the left side and achieved satisfactory clinical results. Therefore, we believe that the choice of approach is mainly based on the characteristics of the patient’s diaphragmatic disease and surgeon familiarity with the approach. The preoperative diagnoses of 9 children in this group were unknown, and diaphragmatic hernia and other gastrointestinal tract malformations were found during the operation, so the choice of preoperative approach was particularly important. We resected the weak portions of the diaphragm via the thoracoabdominal route and sutured the diaphragm intermittently with nonabsorbable sutures to make the cut diaphragm imbricate in order to strengthen the weak area of the diaphragm. The advantage of this technique is that it increases the tension of the diaphragm to evenly distribute the tension throughout the repair area.
With the development of minimally invasive technology, thoracoscopy has gradually been used in the treatment of CDE. We compared the effects of open surgery and thoracoscopy in the treatment of CDE in children. The operation time, chest drainage time, postoperative mechanical ventilation time, postoperative hospital stay and postoperative CCU admission time in the thoracoscopy group were shorter than those in the open group, and the difference between the two groups was statistically significant (P<0.05). We consider the following possible reasons. ① Thoracoscopic surgery adopts the three-hole method, which is less traumatic and less prone to bleeding. The recovery of children is faster after the operation. ② The technique of thoracoscopy requires advanced skill, and the operator and assistant cooperate with each other. ③ We used barbed wire to continuously suture without knots, which greatly shortens the operation time and is obviously better than open surgery.
In this group of 41 children without other thoracoabdominal malformations that need to be corrected, we used thoracoscopic diaphragm plication. Various techniques of diaphragmatic plication have also been employed. All techniques aim to reduce the abundant diaphragmatic surface and lower the diaphragmatic dome. Various suturing methods have been used, including interrupted horizontal mattress sutures, multiple parallel U sutures, figure-eight sutures, continuous running sutures, and endostaplers. Various nonabsorbable and also absorbable sutures have been used. We used barbed wire to suture the diaphragm from the outside to the inside in a continuous imbricated fashion to strengthen the diaphragm. Combined with the literature and our experience, compared with ordinary absorbable sutures, continuous suturing of the diaphragm with barbed wire has the following advantages. ①Starting from the second stitch, slippage is not easy after tightening the suture. One stitch is sewn to tighten one stitch, and no knot is needed during the suture process, which greatly shortens the operation time. ②The diaphragms were sutured continuously by barbed wire to make the diaphragms stretch evenly from the center in all directions. The tension distribution was uniform so that the movement of the diaphragms was more coherent. The diaphragms were not ischemic due to overtight suturing, and the suture did not relax to cause recurrence. ③Barbed wire sutures are closes, have less bleeding, have a wireless knot, are absorbable, and have wireless knot reactions and residual suture. There is a view that continuous sutures may compromise suture safety, and loosening of the knot may affect the folding of the entire diaphragm, but there is no evidence to support this view [11]. A. Parlak et al. and others adopted the double-purse suture method to strengthen the diaphragm, achieving a better clinical effect [12]. The usual advantages of thoracoscopy, such as reduced postoperative pain, satisfactory appearance and rapid recovery, are also applicable in our surgery, which should be the preferred treatment for CDE.