The development and clinical effect of a new type of transoropharyngeal surgical exposure system

English Keywords:Multifunctional rectangle transoral exposure retractor(MRTER)  Atlantoaxial dislocation  Basilar invagination  Transoral anterior reduction and plate fixation(TARP)

English Abstract:

  【Abstract】 Objectives: To develop a new type of multifunctional rectangle transoral exposure retractor(MRTER) and explore its clinical application value. Methods: From 2020 to 2025, we performed 310 cases of transoropharyngeal atlantoaxial surgery, of which 162 cases used Codman retractors[Codman group, 72 males and 90 females, aged 9-67 years old, 47 cases were with simple atlantoaxial dislocation(AAD), 115 cases were with basilar invagination], and 148 cases used the MRTER retractor system(MRTER group, 63 males and 85 females, aged 6-72 years old, 39 cases were with AAD, 109 cases were with basilar invagination). The main clinical symptoms of the patients included cervical pain and restricted mobility in 49 cases, torticollis in 54 cases, weak and numbness of the limbs in 259 cases, finger inflexibility in 43 cases, walking instability in 178 cases, and bladder dysfunction in 5 cases. After admission, a transoral atlantoaxial reduction and plate internal fixation(TARP) was performed. Among the patients, 86 with AAD did not undergo a soft palate split, and 224 patients with basilar invagination underwent a soft palate split to expand the exposure and then underwent transoral release and reduction+TARP procedures. Intraoperative oral opening distance(D value) and oral floor field of view area(S value) were measured to evaluate the exposure ability of the retractor system. The global reduction rate of atlantoaxial dislocation was measured on the cervical sagittal CT film, and the JOA score improvement rate at the final follow-up was calculated to evaluate the effect of the operation. Results: The surgical procedure of 310 patients was smooth, the operation time was 138±25min in Codman group and 118±31min in MRTER group(P<0.05); The surgical blood loss was 105±45mL in Codman group and 113±28mL in MRTER group(P>0.05). The intraoperative measured D value was 4.0±2.1cm in Codman group and 4.2±1.9cm in MRTER group(P>0.05); the S value was 6.3±2.8cm2 in Codman group and 7.1±3.1cm2 in MRTER group(P<0.05). After operation, the symptoms of headache and neck pain were significantly relieved; the symptoms of limb numbness, weakness and walking instability were improved to varying degrees. The overall reduction rate of AAD was 81.3% in Codman group, and 82.5% in MRTER group(P>0.05); JOA improvement rate was 71% in Codman group, and 73% in MRTER group(P>0.05). Conclusions: The new MRTER exposure system provides an effective auxiliary tool for the implementation of atlantoaxial transoropharyngeal surgery.