Thyroidectomy by lateral approach our experience of 218 cases

INTRODUCTION

The traditionally taught technique for conventional thyroidectomy is via midline splitting of strap muscles (midline approach-MA). Lateral approach (LA) uses the same central neck incision but approaches thyroid gland postero-laterally between the anterior border of sternocleidomastoid (SCM) and strap muscles. Thyroidectomy is the commonest endocrine surgical procedure undertaken throughout the world. Although it is one of the most frequently performed surgical procedure worldwide, it was during the last century that, it become an accepted operation. Many thyroid surgeons contributed over the last 100 years to make thyroidectomy a very safe operation with a complication rate around 1-2%.^1-3 Complications of 3 thyroid surgery are directly related to the extent of the resection and inversely proportional to the experience of the operating surgeons.^4-7 The cornerstones of safe and effective thyroid surgery are an adequate training undertaking of the anatomy and pathology, as well as meticulous bloodless dissection. The traditional technique for thyroidectomy is via midline splitting of the strap muscles (midline approach).⁸ Lateral approach uses the same central neck incision that approach thyroid gland postero-laterally between the anterior border of sterno-cleiodomastoid muscle (SCM) and strap muscles.^9-11 Critical structure that require identification and preservation in thyroid surgery such as parathyroid gland and recurrent laryngeal nerve are postero-laterally located in relation to thyroid lobe. Lateral approach allows as easier access in to surgical field for identification on these critical and vital structure with minimum retraction and pulling of strap muscle.⁹ This technique usually reserved for recurrent or redo thyroid surgery to avoid extensive scarring and adhesion after previous surgery. It is also used for para thyroid surgery.¹⁰ Trans axillary endoscopic and robotic thyroidectomy approaches also uses the same lateral approach to reach and dissect thyroid gland.^12-16 Few publications state the efficacy of the lateral approach and most authors conclude that a lateral approach offers excellent visualization of vital structure.¹¹ Lateral approach to thyroid is a good alternative to standard midline exploration.^17-18 And this approach is practiced in NIENT, Dhaka for recurrent thyroidectomy, hemithyroidectomy, total thyroidectomy with neck dissection and para-thyroidectomy operations. Study was performed on a total 218 cases at NIENT, Dhaka via lateral approach including both primary thyroid surgeries, revision thyroid surgeries along with neck dissection to see the safety effectiveness and probable outcome.

METHODS

This was a prospective study which was conducted in the department of ENT, National institute of ENT, Tejgaon, Dhaka from July 2015 to June 2019. A total number of 218 cases of thyroid surgeries were performed using this procedure. Patients were selected by simple random sampling technique. Detailed history was taken and every patient was examined thoroughly specially focusing on the neck. All patients were done USG of the neck, Fine needle aspiration cytology (FNAC) and thyroid function test. All procedures were done by a single surgeon. Data were analyzed by SPSS software.

Inclusion criteria

Inclusion criteria were benign primary thyroid lesions requiring surgery, thyroid malignancy with or without neck node metastasis and revision thyroid surgery.

Exclusion criteria

Thyroid lesions requiring surgery secondary to other neck pathology, advanced thyroid malignancy involving common carotid artery, pre-vertebral fascia and mediastinum, anaplastic carcinoma of thyroid, patients unfit for surgery and patients not giving consent.

RESULTS

Age distribution of thyroid patients ranges from 10 to 70 years, mean age 38.5±8.10 years and most of the patients belonged to 31-40 years age group (Table 1). Out of 218 thyroid diseases, 80 were carcinoma thyroid, among them most common age group was between 31-40, Mean age 38.5±8.10 (Table 2). Most common age group for benign thyroid diseases was 31-40 age (Table 3). Out of 80 carcinoma thyroid, 28 patients had lymph node metastasis; among the 218 patients 138 cases were benign thyroid lesions, among them nodular goiters were 126 (91.30%), follicular adenoma 8 (5.79%); toxic MNG 4 (2.89%); out of 80 cases of carcinoma thyroid 75 (93.75%) were papillary carcinoma thyroid, 02 (2.57%) were follicular carcinoma and 03 (3.75%) were medullary carcinoma (Table 4). Multinodular goiter used total thyroidectomy were 42.20% (Table 5). Blood loss were highest on Toxic goiter (Table 6). Patients with unilateral benign thyroid lesion underwent hemi thyroidectomy, multinodular goiter involving both lobes and toxic nodular goiter underwent total thyroidectomy. Differentiated thyroid carcinoma were treated with total thyroidectomy with CND. Patients of carcinoma thyroid with neck node metastasis received total thyroidectomy with CND and SND (selective neck dissection) or MRND (modified radical neck dissection) where appropriate. In our study most common complication was temporary para-thyroid insufficiency in 47 cases 27.97%, and permanent parathyroid insufficiency was in 2 cases 1.19%, up to one year follow up (Table 7).

Recurrent laryngeal nerve (RLNS).

DISCUSSION

Thyroidectomy is the commonest surgical procedure undertaken throughout the world in endocrine and head neck surgery. Common complications of thyroidectomy are RLN injury, EBSLN injury, para thyroid insufficiency and hemorrhage. In lateral approach thyroidectomy we can easily identify the superior thyroid vessels and by individual ligation of these vessels can prevent EBSLN injury. Landmarks for identification of RLN are ITA (inferior thyroid artery), ZT and lower border of inferior cornu of thyroid cartilage can be easily accessed in LA and thereby easy to identify RLN. In LA there is no need to cut the strap muscle in any size of thyroid. Strap muscle cutting lead to fibrosis with laryngo-tracheal fixation that impairs vertical mobility together with strap muscle. Temporary malfunction with the resulting deleterious effect on voice and swallowing.¹⁹ In our study among 218 cases 177 cases were female and rest were male. 81.19% of our study subjects were female and male to female ratio 1:4.3, ages ranges from 10-70 years, mean age 38.5±8.10, most of the patients belongs to 31-40 years of age. In our study the highest prevalence of thyroidectomy was in women 81.19%. In line with this study, Yan et al showed that of 7385 patients undergoing thyroidectomy; ratio of male to female was 1:5.24, while the mean age of patient was more than 40 years.^20,21 In fact, the overall findings of many epidemiological studies indicated a higher prevalence of thyroid disorders among women than man.^21,22 Out of 218 thyroid diseases 80 cases were carcinoma thyroid, most common age group was 31-40 years. Rest of 138 were benign thyroid diseases. In this group most common age belonged to 31-40 years. Out of 218 patients 138 cases were benign thyroid lesions among them nodular goiter 126 (91.30), follicular adenoma 8 (5.79), toxic MNG 4 (2.89), 80 cases of carcinoma thyroid among which 75 were papillary carcinoma thyroid (93.75), 02 were follicular carcinoma (2.57%) and 03 were medullary carcinoma (3.75%). Out of 80 malignant cases, 28 patients had lymph node metastasis. Patients with benign thyroid lesion underwent hemi thyroidectomy for nodular goiter 34 (15.59%), hemi thyroidectomy for follicular adenoma 8 (3.66%), multinodular goiter involving both lobe of thyroid done total thyroidectomy was 92 (42.20%). Papillary carcinoma thyroid underwent total thyroidectomy with central neck dissection 40 (18.34%), total thyroidectomy with CND and SND (level II to IV) 23 cases (10.55%), total thyroidectomy with CND and bilateral MRND 02 cases 0.91%, and completion thyroidectomy 8 cases 3.66%. Medullary carcinoma with neck node metastasis underwent total thyroidectomy with CND and bilateral MRDN type III 3 cases 1.30%; 4 cases of follicular carcinoma done total thyroidectomy with CND 1.83% and 4 cases of toxic MNG done total thyroidectomy 1.83%. In our study most common complication was temporary parathyroid insufficiency 47 (27.97%), and permanent parathyroid insufficiency 2 (1.19%) up to one year follow up. In many previous studies, hypocalcemia was reported about 2-55% and 0.4-13.8% respectively.^23-26 Suwnna et al reported immediate hypocalcemia was observed in 38.55% of patients.²⁶ The lower rate in our study may be due to identification of parathyroid glands and maintaining its vascularity. Minimum amount of blood loss in our procedure due to better exposure and individual ligations of superior thyroid vessels, middle thyroid vein and inferior thyroid artery.

Limitations

The present study was conducted at a very short period of time. For being a study in a single community with comparatively small number of sample size, the study result may not reflect the exact scenarios of the whole world.

CONCLUSION

Lateral approach to thyroid is a safe alternative to the standard approach for re-explorative thyroid surgery. Lateral approach to thyroid is an alternative to both conventional thyroidectomy and for parathyroid explorations.

Recommendations

We are recommending multi-centre study with large sample size. Longer period study can give a better platform to evaluate this issue properly.

Funding: No funding sources

Conflict of interest: None declared

Ethical approval: The study was approved by the Institutional Ethics Committee

REFERENCES

1. 1. Serpel JW, Lee JC, Yeung MJ, Grodski S, Johnson W, Bailey M. Differential recurrent laryngeal nerve palsy rates after thyroidectomy. Surgery. 2014;156(5):1157-66.
2. 2. Kasemsuwan L, Nubthuenetr S. Recurrent laryngeal nerve paralysis: a complication of thyroidectomy. J Otolaryngol. 1997;26(6):365-7.
3. 3. Sarkar S, Banerjee S, Sarkar R, Sik DB. A Review on the H istory of ‘Thyroid Surgery’. Indian J Surg. 2016;78(1):32-6.
4. 4. Udelsman R. Experience counts. Ann Surg. 2004;240:26-7.
5. 5. Ito Y, Iwase H, Tanaka H, Yuasa H, Kureyama Y, Yamashita H, et al. Metachronous primary hyperparathyroidism due to a parathyroid adenoma and a subsequent carcinoma: report of a case. Surg Today. 2001;31:895-8.
6. 6. Hermann M, Hellebart C, Freissmuth M. Neuromonitoring in thyroid surgery: prospective evaluation of intraoperative electrophysiological responses for the prediction of recurrent laryngeal nerve injury. Ann Surg. 2004;240:9-17.
7. 7. Zambudio AR, Rodriguez J, Riquelme J, Soria T, Canteras M, Parrilla P. Prospective study of postoperative complications after total thyroidectomy for multinodular goitres by surgeons with experience in endocrine surgery. Ann Surg. 2004;240:18-25.
8. 8. Giddings AE. The history of thyroidectomy. J R Soc Med. 1998;91(33):3-6.
9. 9. Alaa M. Lateral approach to attack superior thyroid vascular pedicle eliminates the need for strap muscles cutting during thyroidectomy. Med J Cairo Univ. 2015;83:125134.
10. 10. Dissanayake DDMC, Fernando RF, Dissanayake IJ. Lateral approach to thyroid: a good technique for re-operative thyroid surgery. World J Endocr Surg. 2016;8(2):141-2.
11. 11. Oertli Surgery of the Thyroid and Parathyroid Glands Springer; 2012.
12. 12. Palazzo FF. Endocrine surgical technique: endoscopic thyroidectomy via the lateral approach. Surg Endosc Other Interv Tech. 2006;20:339-42.
13. 13. Sebag F, Palazzo FF, Harding J. Endoscopic lateral approach thyroid lobectomy: safe evolution from endoscopic parathyroidectomy. World J Surg. 2006;30(5):802-5.
14. 14. Giannopoulos G, Kang SW, Jeong JJ. Robotic thyroidectomy for benign thyroid diseases: a stepwise strategy to the adoption of robotic thyroidectomy (gasless, trans axillary approach). Surg Laparosc Endosc Percutan Tech. 2013;23(3):312-5.
15. 15. Kiriakopoulos A, Linos D. Gasless trans axillary robotic versus endoscopic thyroidectomy: exploring the frontiers of scar less thyroidectomy through a preliminary comparison study. Surg Endosc. 2012;26(10):2797-801.
16. 16. Henry JF, Sabag F. Lateral endoscopic approach for thyroid and parathyroid. Chir. 2006;131:51-6.
17. 17. Napolitano C, Vix M, Mutter D, Marescaux J. Thyroid and parathyroid surgery: is the medial approach truly elective? Technique and advantage of the lateral approach. Minerva Chir. 1997;52(11):1393-5.
18. 18. Henry JF, Sebag F. Lateral endoscopic approach for thyroid and parathyroid surgery. Ann Chir. 2006;131(1):51-6.
19. 19. Lombardi CP, Raffaelli M, D’alatri L. Voice and swallowing changes after thyroidectomy in patients without inferior laryngeal nerve injuries. Surgery. 2006;140(6):1026-34.
20. 20. Yan HX, Pang P, Wang FL, Tian W, Luo YK, Huang W, et al. Dynamic profile of differentiated thyroid cancer in male and female patients with thyroidectomy during 2002013 in China, a retrospective study. Sci Rep. 2017;7:15832.
21. 21. Huang CF, Jeng Y, Chen KD, Yu JK, Shih CM, Huang SM, et al. The pre-operative evaluation prevents the post-operative complications of thyroidectomy. Ann Med Surg (Lond). 2015;4:5-10.
22. 22. Vanderpump MP. The epidemiology of thyroid disease. Br Med Bull. 2011;99:39-51.
23. 23. Bourrel C, Uzzan B, Tison P, Despreaux G, Frachet B, Modigliani E, et al. Transient hypocalcemia after thyroidectomy. Ann Otol Rhinol Laryngol. 1993;102:496-501.
24. 24. Abboud B, Sargi Z, Akkam M, Sleilaty F. Risk factors for post-thyroidectomy hypocalcemia. J Am Coll Surg. 2002;195:456-61.
25. 25. Seo ST, Chang JW, Jin J, Lim YC, Rha KS, Koo BS. Transient and permanent hypocalcemia after total thyroidectomy: Early predictive factors and long-term follow-up results. Surgery. 2015;158:1492-9.
26. 26. Suwannasarn M, Jongjaroenprasert W, Chayangsu P, Suvikapakornkul R, Sriphrapradang C. Single measurement of intact parathyroid hormone after thyroidectomy can predict transient and permanent hypoparathyroidism: A prospective study. Asian J Surg. 2017;40:350-6.