Comparative Study Of Totally Endoscopic And Minimally Invasive Video Assisted Techniques In Thyroid And Parathyroid Operations

ObjectiveCurrent endoscopic techniques in surgery of thyroid and parathyroid, according to incision of neck existing or not, are divided into totally endoscopic and minimally invasive video assisted techniques. Totally endoscopic technique is comprised of different approaches, including areola, anterior chest, axilla, hybrid approach, and so on. The published studies have confirmed that endoscopic technique, either totally endoscopic or video assisted technique, has advantages of better postoperative cosmetic effect, less invasion and rapider recovery. But we haven’t found any comprehensive comparison between these two endoscopic procedures. The aim of our study is, by comparing totally endoscopic and minimally invasive video assisted techniques in terms of the clinical indications, surgical techniques, postoperative recovery and patient satisfaction, to assess their safeties and effects and to discuss the reasons in objective and subjective factors which resulted in differences between two surgical procedures. We expect endoscopic technique will have a more rational and effective application in treatment of thyroid and parathyroid diseases, which will bring more benefits to patients.Methods This study includes845cases of benign and malignant thyroid diseases, and238cases of benign parathyroid diseases from January2006to December2009. Totally endoscopic procedures were performed in93thyroid cases and3parathyroid cases, while minimally invasive video assisted thyroidectomy and parathyroidectomy were performed in752cases and235cases respectively.Totally endoscopic and minimally invasive video assisted thyroidectomy were compared in terms of preoperative selection criteria, operative data, postoperative recovery and patient satisfaction. The learning curves of operative time were drawn according to our experiences. Preoperative selection criteria included pathology of thyroid diseases (Graves’ diseases, benign or malignant), thyroid volume, nodular diameter, thyroiditis, history of radiation and operation in the neck. Operative outcomes involved patient gender, age, thyroid volume, nodular diameter, types of procedure, operative time, intraoperative blood loss and conversion. Postoperative outcomes included transient or persistent palsy of recurrent laryngeal nerve, transient or persistent serum hypocalcemia, bleeding, infection, subcutaneous emphysema and ecchymosis, discomfort of anterior chest and pain. Postoperative recovery indexes consisted of duration admitted in ICU, time of food intake and duration of hospitalization. Postoperative pain was evaluated by visual analog scale (scale range,0-10) at time0(recovery room), time1(after6hours), time2(after12hours), and time3(after24hours). Satisfaction and cosmetic result were recorded by a telephone questionnaire, whose scale ranged from very satisfied to dissatisfied. Learning curves of operative time were drawn respectively according to our practice experiences in lobectomy by means of totally endoscopic and minimally invasive video assisted procedures.For cases of differentiated thryorid cancer treated with minimally invasive video assisted technique, the preoperative screen criteria, types of operation, lymph-node dissection, posteoprative complications and results of follow-up were analyzed. We also discussed the feasibility, safety and effect of thyroid cancer operations with endoscopic technique and further analyzed the new and hot topics in this area.Totally endoscopic and minimally invasive video assisted parathyroidectomy were compared in terms of preoperative selection criteria, operative and postoperative outcomes. Learning curve of operative time was drawn for MIVAP. Preoperative selection criteria included thyroid volume, diameter of adenoma, preoperative location and diagnosis, thyroiditis, history of operation in the neck. Operative and postoperative outcomes consisted of diameter of adenoma, operative time, location of adenoma, concomitant thyroidectomy, conversion, transient or persistent palsy of recurrent laryngeal nerve, transient or persistent serum hypocalcemia and duration of hospitalization. Results93cases of totally endoscopic thyroidectomy (TET), including42cases via areola approach and51cases via anterior chest approach, were performed successfully except2cases converted. Minimally invasive video assisted thyroidectomy (MIVAT) was carried out in752cases, among which6cases were converted and178cases of total thyroidectomy were performed for thyroid carcinoma. Totally endoscopic parathyroidectomy (TEP) was performed successfully in all3cases, including2cases via areola approach and1case via anterior chest approach.235cases of minimally invasive video assisted parathyroidectomy (MIVAP) were performed including8cases of conversion.Totally endoscopic group, whose average age was lower (32.7±6.57vs39.8±12.17years, p<0.05), had more female patients than MIVAT group (97.8%vs78.5%, p<0.05). TET allowed larger thyroid volume (25.2±4.83vs14.7±4.83mL,p <0.0001) and nodular diameter(25.8±1.05vs22.1±1.03mm, p<0.05). Compared to TET group, MIVAT group had more total thyroidectomies (79.3%vs9.7%, p<0.05) and less lobectomies (20.7%vs90.3%,p<0.05). MIVAT group had a result of less blood loss (9.4±8.52vs32.1±25.13mL, p<0.0001), less operative time for lobectomy (28.2±7.05vs112.8±22.72min, p<0.0001) and total thyroidectomy (40.6±9.23vs168.3±34.53min, p<0.0001). TET and MIVAT groups had no statistical differences in preoperative diagnosis, thyroiditis and intraoperative conversion (p>0.05).No intraoperative complications, such as trachea injury, hypercapnia, respiratory acidosis, tachycardia, subcutaneous emphysema, or inadvertent pneumothorax, occurred in either TET or MIVAT group. Transient damage to recurrent laryngeal nerve (RLN) occurred in two patients in each group (p>0.05). No postoperatively persistent injury to RLN, hypocalcemia, bleeding, or infection was recorded (p>0.05). Subcutaneous emphysema occurred in2patients (2.2%) and subcutaneous ecchymosis occurred in3patients (3.2%). The differences in subcutaneous emphysema and ecchymosis between the two groups were not significant(p>0.05).Significant differences were recorded in the chest discomfort (8.6%vs0%, p< 0.05) and pain evaluation (3.7±1.25vs1.8±0.76,p<0.0001). According to the VAS assessment, no severe pain was recorded and pain at time2(after12hours) in the TET groupwas was significantly higher than that in the MIVAT group (p<0.0001). No patients required postoperative admission to the intensive care unit (ICU). The average food-intake time postoperatively was1day in both groups (p=1). Mean satisfaction score was similar between two groups (p=0.2). Patients in MIVAT group had a significantly shorter hospital length of stay than the TET patients (1.0±0vs3.5±0.83days,p<0.0001).In MIVAT group178patients were diagnosed or suspected differentiated thyroid cancer preoperatively. Femal patients showed a predominance of86.0%. Mean age was38.6years. The mean diameter of cancerous nodules was9.2mm. Among these cases174cases of papillary carcinoma and4cases of follicular caicima were diagnosed preoperatively and5cases showed evidences of lymph-node metastases in the region VI. Total thyroidectomy was performed for173patents. Except one operation were converted (The entrance of RLN was infiltrated by the carcinoma), all the procedures were performed successfully. Central neck dissection was also performed in5patients after total thyroidectomy. The number of lymph node resected was from1to5. No permenant RLN and parathyroid damage were recorded postoperatively. One follicular carcinoma was diagnosed follicular adenoma histologically and there’s no other unexpected diagonosis recorded. Druing the follow-up of24to72months, no relapse occurred.2cases of lymph-node metastases and one case of distant metastases were recorded in three patients with papillary carcinoma.Because the sample size in TEP group was too small, no statistical analysis but simple comparison was done between TEP and MIVAP groups. Two groups had a similar selection criteria on thyroid volume (<25mL) and diameter of parathyroid adenoma (<3cm). The preoperative location of adenoma in MIVAP group was less strictly demanded than TEP group because bilateral exploration can be performed more easily with MIVAP. History of thyroiditis and operation in the neck were contraindications in both groups, but MIVAP can be done by a lateral access to avoid the adhesion and fibrous hyperplasia caused by the previous operation. Primary hyperparathyroidism is the optimal indication for both groups, but MIVAP is more suitable for resection of bilateral adenomas.Female sex had predominance in both TEP and MIVAP groups. MIVAP group showed shorter mean operative time (30.6vs72.6min) and postoperative duration of hospitalization (1.0vs5.5d) than TEP group. All3cases were completed in TEP group and no conversion was done. In MIVAP group227cases were performed successfully except8cases were converted:5cases of missing adenoma,1case of false positive result from quick intraoperative intact parathyroid hormone assay (qPTHa),1case of difficult dissection of parathyroid tissue and1case of unexpected papillary carcinoma by intraoperative frozen section.No RLN persistent injury was recorded in both groups. No transient RLN injury and hypocalcemia occurred in TEP group.2cases of transient RLN injury,7cases of transient hypocalcemia and1case of persistent hypocalcemia were recoeded in MIVAP group. One case of persistent hypocalcemia could be caused by a second exploration with MIVAP after the false positive result of qPTHa during the first operation, and the other missing adenoma in the opposite side existed.Conclusions (1) Totally endoscopic and minimally invasive video assisted operations in treatment of thyroid and parathyroid diseases, which have advantages of postoperative cosmetic effect and high patient satisfaction, are both safe and effective.(2) TET can be used to treat larger thyroid nodules than MIVAT. MIVAT shows indications for benign and malignant thyroid diseases while TET is mainly used for benign disease at present.(3) MIVAT for high differentiated thryroid cancer assessed as "low risk" is safe and effective.(4) MIVAT has advantages of shorter operative time, less postoperative pain and physical invasiveness while TET shows better postoperative cosmetic effect in the neck.(5) MIVAP is a quick, safe and effective procedure with good cosmetic effect for PHPT.(6) Screening plays a very important role in detection, diagnosis and treatment of parathyroid diseases. It can help find more patients.