Postoperative Recurrent Laryngeal Nerve Palsy Research Articles

The role of intraoperative neuromonitoring of recurrent laryngeal nerve during thyroidectomy: A comparative study on 1000 nerves at risk

The role of intraoperative neuromonitoring of recurrent laryngeal nerve (RLN) during thyroidectomy has not been well established. The present study evaluates whether RLN injury can be reduced by the application of this technique during thyroidectomy in a single center. Of 1000 RLNs that were at risk of injury in 639 consecutive patients who underwent thyroidectomy, the outcome of 501 RLNs with the use of neuromonitoring was compared with that of 499 nerves that were operated by routine identification only. The incidences of RLN paralysis were compared between the 2 groups and the assigned risk subgroups. Postoperative palsy was identified in 47 RLNs (4.7%), with complete recovery in 37 of 44 RLNs (84%) without documented injury. The overall incidence of postoperative RLN paralysis was significantly higher during thyroidectomy for malignancy (P = .025) and secondary thyroidectomy (P = .017). There was no significant difference in postoperative, transient, and permanent paralysis rates between the neuromonitoring and control groups. In subgroup analysis, the postoperative RLN palsy rate was higher during reoperative thyroidectomy (19% vs 4.6%; P = .019) in the control group but not in the neuromonitoring group (7.8% vs 3.8%; P > .05). Neuromonitoring of the RLN during thyroid surgery could not be demonstrated to reduce RLN injury significantly, compared with the adoption of routine RLN identification. However, its application can be considered for selected high-risk thyroidectomies.

The Efficacy of Intraoperative Corticosteroids in Recurrent Laryngeal Nerve Palsy after Thyroid Surgery

Recurrent laryngeal nerve palsy (RLNP) is one of the most common complications after thyroidectomy. We aim to evaluate the role of intraoperative corticosteroids in preventing or treating postoperative RLNP. We conducted a prospective study of 295 patients who underwent either total lobectomy or total thyroidectomy with or without using intraoperative corticosteroids. All cases were operated on by the same surgeon. Measurement of the RLNP rate was based on the number of nerves at risk. Data were analyzed for differences in postoperative temporary or permanent RLNP rate and recovery days. The rate of temporary/permanent RLNP was 5.7% (11 out of 194)/0.52% (1 out of 194) and 6.9% (12 out of 173)/0.58% (1 out of 173) according to groups with and without corticosteroids. This difference did not reach statistical significance. Among those 23 patients who recovered from RLNP, the mean time to recovery was significantly shorter for patients receiving intraoperative steroids (28.6 vs. 40.5 days, P = 0.045). A single dose of intraoperative corticosteroids did not produce any benefit in terms of reducing the postoperative temporary/permanent RLNP rate, but it did shorten the recovery time for patients suffering from temporary RLNP.

反回神経麻痺の臨床統計―当教室における最近６年間の検討―

Statistical analysis was performed on 271 patients with recurrent laryngeal nerve paralysis (RLNP) diagnosed at the Department of Otolaryngology-Head and Neck Surgery of Kumamoto university hospital between January 1999 and December 2004. There were 141 males (52.0%) and 130 females (48.0%). The left vocal fold was affected in 165 cases (60.9%), the right in 77 cases (28.4%) and both in 29 cases (10.7%). There were 124 cases of postoperative RLNP (45.8%), and 147 cases of RLNP not related to surgery (54.2%). The mean age of patients with RLNP not related to surgery was higher than that of those with postoperative RLNP for both males and females. With aging, RLNP due to malignant neoplasms decreased among males and that due to aneurysm or cerebral infarction increased. Among females, RLNP due to malignant neoplasms increased with age. We should be aware of such complications as aortic aneurysm and cerebral infarction as a cause of RLNP in addition to malignant neoplasms.

Recurrent laryngeal nerve palsy after thyroidectomy with routine identification of the recurrent laryngeal nerve

The aim of this study was to assess the risk of recurrent laryngeal nerve palsy (RLNP) after thyroidectomy with routine identification of the recurrent laryngeal nerve (RLN) during the operation. The present study was confined to 521 patients, 348 total lobectomies and 178 total thyroidectomies, treated by the same surgeon. Temporary and permanent RLNP rates were analyzed for patient groups with stratification of primary operation for benign thyroid disease, thyroid cancer, Graves' disease, and reoperation. Measurement of the RLNP rate was based on the number of nerves at risk. Twenty-six RLNs in 20 thyroid cancer patients with intentional sacrifice were excluded from analysis. Forty RLNs (40 patients) developed postoperative RLNP. Complete recovery of RLN function was documented for 35 of the 37 patients (94.6%) whose RLN integrity had been ensured intraoperatively. Recovery from temporary RLNP ranged from 3 days to 4 months (mean, 30.7 days). Overall incidence of temporary and permanent RLNP was 5.1% and 0.9%, respectively. The rates of temporary/permanent RLNP were 4.0/0.2%, 2.0/0.7%, 12.0/1.1%, and 10.8/8.1% for groups classified according to benign thyroid disease, thyroid cancer, Graves' disease, and reoperation, respectively. Operations for thyroid cancer, Graves' disease, and recurrent goiter demonstrated significantly higher RLNP rates. Invasion of RLN was identified in 19.4% of patients with thyroid cancer. Postoperatively, the RLN recovered in most of the patients without documented nerve damage during the operation. Total lobectomy with routine RLN identification is recommended as a basic procedure in thyroid operations.

Schilddrüsenchirurgie: Generalist oder Spezialist?

Thyroid surgery is done in Germany in a considerable numbers of operations (about 110,000 per year). To perform thyroid operations by so called "generalists" or "specialists" have been discussed intensively, however, this issue have not been analyzed in detail. Study material comprised 16,500 consecutive thyroid operations with 30,000 operated sites that have been prospectively documented in the German Thyroid Multicenter Study performed 1998 through 2001. Quality of surgery were analyzed by calculating the inverse relationship between volume and outcome (complication rate). To achieve complication rates (permanent unilateral recurrent laryngeal nerve paralysis and hypocalcemia) of < 1 % (primary surgery) or < 3 % (redo surgery) the minimum number of thyroid operations of lower level of experience (e. g. benign nodular goiter) per year was n=30. The minimum number of operations with higher level of experience was significantly lower (n=3-12) due to the higher level of experience of operating surgeons. In contrast to the rates of postoperative hypocalcemia the rates of postoperative recurrent laryngeal nerve paralysis was clearly related to the number of thyroid operations performed. The high number of thyroid operations in Germany with about 20 % of operations of high level experience are requiring surgical curricula and hospital structures that offer as well generalists as specialists to treat the broad spectrum of thyroid diseases accordingly. To lower the complication rate especially of difficult thyroid operations the level of specialization in Germany have to be increased.

Recurrent laryngeal nerve paralysis (RLNP) following esophagectomy for carcinoma

Background The aim of this study was to report the frequency of post-operative recurrent laryngeal nerve paralysis (RLNP) following resection for esophageal carcinoma. Patients and methods Four hundred and four patients were studied. Diagnosis of post-operative RLNP was performed by indirect laryngoscopy. Tumour characteristics, surgical approach and perioperative morbidity and mortality following esophageal resection were recorded. Results Sixty patients were diagnosed with post-operative RLNP, of whom 47 had a unilateral and 16 a bilateral lesion. RLNP was more frequently diagnosed after transhiatal resection with cervical esophagogastrostomy as compared to abdomino-thoracic resection ( p=0.06). A higher rate of post-operative pneumonia was evident in patients with RLNP (33 of 63 as opposed to 90 of 341; p=0.027). Conclusion RLNP is associated with a significant morbidity, especially pulmonary complications after resection of esophageal cancer.

Continuous laryngeal nerve integrity monitoring during thyroidectomy: Does it reduce risk of injury?

To determine if continuous laryngeal nerve integrity monitoring (NIM) during thyroidectomy is associated with a decreased risk of postoperative recurrent laryngeal nerve (RLN) injury. Retrospective cohort study of 165 patients who underwent thyroidectomy at a resident teaching institution between 1999 and 2002. The control group had 120 nerves at risk (NAR) whereas the NIM group consisted of 116 NAR. Primary outcome measures included postoperative RLN paralysis, paresis, and total injury rates. RLN paralysis occurred in 2.54% NAR in the control group and 0.86% in the NIM group [relative risk (RR) = 0.34, 95% confidence interval (CI95) = 0.04-3.27, P = 0.62]. Temporary RLN paresis occurred in 4.24% NAR in the control group and 3.45% in the NIM group (RR = 0.9, CI95 = 0.23-3.55, P = 0.89). Total RLN injury occurred in 6.78% NAR in the control group and 4.31% in the NIM group (RR = 0.66, CI95 = 0.21-2.09, P = 0.48). When compared to all other NAR, advanced T-stage malignancy was associated with a significantly increased risk of RLN paresis (T4 RR = 9.0, CI95 = 2.56-31.67, P = 0.0006; T3+T4 RR = 7.5, CI95 = 2.17-25.86, P = 0.0001) but not paralysis. NIM did not significantly reduce the risk of RLN paresis in the advanced T-stage subset (T3+T4 RR = 0.36, CI95 = 0.04-3.0, P = 0.59). There were no statistically significant differences in RLN paralysis, paresis, or total injury rates between control and NIM groups, even in subsets with advanced T-stage and increased baseline risk. Advanced T-stage is a significant predictor of RLN paresis in this cohort.

Continuous laryngeal nerve monitoring during thyroidectomy: Does it reduce the injury rate?

Problem: To determine if continuous laryngeal nerve integrity monitoring (NIM) during thyroidectomy is associated with a decreased risk of postoperative recurrent laryngeal nerve (RLN) injury. Methods: This was a cohort study of 165 patients who underwent thyroidectomy at a resident teaching institution between 1999 and 2002. The control group had 120 nerves at risk (NAR) while the NIM group consisted of 116 NAR. Primary outcome measures included postoperative RLN paralysis, paresis, and total injury rates. Results: RLN paralysis occurred in 2.54% of NAR in the control group and 0.86% in the NIM group (RR = 0.34, CI95 = 0.04–3.27, P = 0.62). Temporary RLN paresis occurred in 4.24% of NAR in the control group and 3.45% in the NIM group (RR = 0.9, CI95 = 0.23–3.55, P = 0.89). Total RLN injury occurred in 6.78% of NAR in the control group and 4.31% in the NIM group (RR = 0.66, CI95 = 0.21–2.09, P = 0.48). When compared to all other NAR, advanced T-stage malignancy was associated with a significantly increased risk of RLN paresis (T4 RR = 9.0, CI95 = 2.56–31.67, P = 0.0006; T3+T4 RR = 7.5, CI95 = 2.17–25.86, P = 0.0001) but not paralysis. NIM use did not significantly reduce risk of RLN paresis in the advanced T-stage subset (T3+T4 RR = 0.36, CI95 = 0.04–3.0, P = 0.59). Conclusion: There were no statistically significant differences in RLN paralysis, paresis, or total injury rates between control and NIM groups, even in subsets with advanced T-stage and increased baseline risk. Advanced T-stage is a significant predictor of RLN paresis in this cohort. Significance: NIM does not appear necessary in routine thyroidectomy, although it may be considered in patients with T3 and T4 tumors given an increased risk of RLN injury in these patients. Support: None reported.

Influence of the Refinement of Surgical Technique and Surgeon’s Experience on the Rate of Complications after Total Thyroidectomy for Benign Thyroid Disease

Background: In recent years, many surgeons dealing with endocrine surgery have increasingly performed total thyroidectomy for benign thyroid disease. However, total excision of the thyroid in the treatment of benign lesions has been surrounded by even more controversy than its role in cancer treatment. The complication rate appears to be higher when the operation is done by inexperienced surgeons who have no special skills in endocrine surgery using proper techniques. The aim of this study is to determine whether surgeons experience and the refinement of surgical techniques are associated with postoperative recurrent laryngeal nerve (RLN) palsy or hypocalcemia after total thyroidectomy for benign thyroid disease.Methods: A total of 68 consecutive patients who underwent total thyroidectomy for benign thyroid disease were reviewed. Twenty-six of these were from between January 1998 and June 1999 (first period) and 42 from between June 1999 and September 2000 (second period). Patients were divided into two subgroups according to different periods and different surgical techniques to identify the RLNs and the parathyroid glands. RLNs function was evaluated pre-and post-operatively by an otolaryngologist, and serum calcium levels were measured at the postoperative follow-up. Results: During the first period of the study, transient hypocalcaemia was determined in 8 (31%) patients. Hypocalcaemia was clinically symptomatic in 5 (19%) patients. Transient RLN palsy developed in 4 (15%) patients. Unilateral permanent RLN palsy due to operative injury was observed in 1 (4%) patient. During the second period, we noted transient hypocalcemia in 11 (26%) patients and symptomatic hypocalcemia in 6 (4%) patients. Serum calcium levels returned to normal within 4 weeks after operation in all patients. Neither transient nor permanent RLN palsy was observed during this period.Conclusions: Complications of total thyroidectomy can be minimized with increasing experience and the refinement of surgical technique.

Advantages of recurrent laryngeal nerve identification in thyroidectomy and parathyroidectomy and the importance of preoperative and postoperative laryngoscopic examination in more than 1000 nerves at risk.

Recurrent laryngeal nerve palsy (RLNP) is a major obstacle in thyroid and parathyroid surgery. Therefore, methods that reduce the number of temporary and, especially, permanent recurrent laryngeal nerve palsies are of great interest. One promising way to ensure the integrity of the recurrent laryngeal nerve (RLN) is to identify the nerve always. The first question raised in the present study was whether RLN preparation reduces the number of recurrent laryngeal nerve palsies or whether it introduces additional risks. Second, from former cases we know that the absence of postoperative hoarseness does not exclude RLNP, nor does postoperative hoarseness exclusively imply RLNP. Besides, misdiagnosis is not uncommon. Therefore, preoperative and postoperative laryngoscopic examination was given attention. Patients were investigated 1 to 7 days before and 3 to 7 days after surgery. When an RLNP was identified, patients were followed up in a 2-week rhythm the first few times and every 6 to 8 weeks thereafter until RLNP resolved or it was considered permanent after 2 years. We prospectively investigated 608 surgical patients with 1080 nerves at risk. Because different diseases might have different rates of postoperative RLNP, we analyzed benign thyroid disease (680 nerves at risk), thyroid malignoma (321 nerves at risk), and hyperparathyroidism (79 nerves at risk) separately. Patients undergoing primary surgery (no prior thyroid surgery) and secondary interventions (there were one or more thyroid operations before this intervention) were evaluated separately. We found 3.4%, 7.2%, and 2.5% of temporary recurrent laryngeal nerve palsies per nerve in the benign thyroid disease, thyroid malignoma, and hyperparathyroidism groups, respectively. The prevalence of recurrent laryngeal nerve palsies in these groups was 0.3%, 1.2%, and 0%, respectively. Conforming with other studies, the total number of recurrent laryngeal nerve palsies (temporary and permanent) was not increased compared with cases with no RLN preparation, whereas the number of permanent recurrent laryngeal nerve palsies was markedly reduced. An RLN was always identifiable. Astonishingly, the restitution of an RLNP was up to 2 years in duration; however, most restitutions occurred within the first 6 months. Thirty cases of hoarseness appeared or were intensified after surgery and were not caused by RLNP. Eleven cases of postoperative RLNP had no detectable hoarseness. Besides indirect laryngoscopy, videostroboscopy should be performed in all cases with no evident bilateral normal laryngeal function or normal voice. Otherwise, the incidence of false-positive or false-negative diagnosis of RLNP is likely to be increased.

Causes of recurrent laryngeal nerve paralysis

Objective: Persistent hoarseness due to recurrent laryngeal nerve paralysis (RLNP) reduces the quality of life unless it is adequately treated. This study examined the indications for phonosurgical intervention in patients with RLNP. Materials and methods: The medical records of the Ehime University Hospital, Ehime, Japan, from October 1976 until December 1997 were reviewed retrospectively to identify patients with RLNP. The data collected included age, gender, paralyzed side, and cause of paralysis. Results: Four hundred and sixty-six patients with RLNP were identified: 262 males and 204 females. Unilateral RLNP was present in 422 patients, while 44 presented with bilateral RLNP. The incidence was relatively high in the 7th and 8th decades, and was twice as high in male patients as in female patients. The 466 patients were divided into 2 groups: Group 1 included 225 patients seen before January 1987, and Group 2 included 241 patients seen after this date. The number of patients with postoperative RLNP was significantly higher in Group 2 (124 of 239 patients) than in Group 1 (65 of 227 patients) ( P<0.05). Surgery for cardiovascular disease, esophageal cancer, and skull base and thyroid gland tumors contributed to this increased incidence of postoperative RLNP. Conclusions: Patients with persistent unilateral RLNP require appropriate treatment for hoarseness, regardless of its cause. Since the incidence of RLNP related to surgery was significantly increased in Group 2, phonosurgery has become more important for improving the quality of life of these patients.

Postoperative left recurrent laryngeal nerve palsy possibly caused by coincidental swelling of the metastatic mediastinal lymph node

Postoperative left recurrent laryngeal nerve palsy possibly caused by coincidental swelling of the metastatic mediastinal lymph node

バセドウ病甲状腺亜全摘術の合併症

Between 1992 and 1998, 67 patients underwent a subtotal thyroidectomy for hyperthyroidism (Basedow disease). Postoperative complications occurred in 6 patients (9.0%). In 4 patients (6.0%), postoperative bleeding occurred, which was stopped by a reoperation. Postoperative recurrent laryngeal nerve palsy occurred in 2 patients (3.0%); they recovered from the palsy within three weeks. One patient (1.5% needed vitamin) for 5 years after the operation due to hypo calcemia.We should choose a subtotal thyroidectomy as treatment for hyperthyroidism because very few patients are expected to suffer from severe complications.

Recurrent laryngeal nerve palsy after cardiovascular surgery: Relationship to the placement of a transesophageal echocardiographic probe

Objective: To examine the relationship between the incidence of recurrent laryngeal nerve palsy after cardiovascular surgery and the placement of a transesophageal echocardiographic probe. Design: A prospective clinical study. Setting: A single-institutional study in a university hospital. Participants: One hundred sixteen patients undergoing cardiovascular surgery. Interventions: All patients were assigned into one of two groups: 64 patients in whom transesophageal echocardiography (TEE) was performed and 52 patients in whom TEE was not performed during surgery. The incidence of recurrent laryngeal nerve palsy was examined and compared between the two groups. Measurements and Main Results: Five of 64 patients (7.8%) in whom TEE was monitored and 3 of 52 patients (5.8%) in whom TEE was not monitored were diagnosed with recurrent laryngeal nerve palsy postoperatively. There was no statistically significant difference between the incidence of recurrent laryngeal nerve palsy in patients with intraoperative TEE monitoring, and patients without it. The durations of surgery, anesthesia, and cardiopulmonary bypass were significantly longer in patients with nerve palsy than those without it. Conclusion: These results suggest that placement of the transesophageal echocardiographic probe is not responsible for postoperative recurrent laryngeal nerve palsy. It seems likely that surgical manipulation itself and the durations of surgery, cardiopulmonary bypass, and tracheal intubation are related to the incidence of laryngeal nerve palsy.

甲状腺分化癌の手術における反回神経麻痺について

The factors associated with postoperative recurrent laryngeal nerve palsy (RLNP) were analyzed in 718 patients with differentiated thyroid cancer (size of cancer tumor > 11 mm) treated between 1991 and 1995. The papillary cancer group included 658 patients. Of these 658 patients,114developed RLNP (17.3%). Follicular cancer group was 60 patients. Of the 60 patients,2developed RLNP (3.3%). The RLNP in papillary cancer group was significantly worse than that in follicular cancer group (P<0.01). The risk factor for RLNP was analyzed. In papillary cancer group, age, size of cancer tumor, adhesion of the tumor to the recurrent laryngeal nerve, and neck dissection were identified as significant risk factors for occurence of RLNP. Papillary cancer was more malignant, if age was older and size of cancer tumor was bigger.

反回神経麻ひの臨床統計 愛媛大学における過去２１年間の検討

We reviewed 442 (males : 248, females : 194) patients with recurrent laryngeal nerve paralysis (RLNP) at Ehime University Hospital from 1976 through 1996. Their mean age was 55.8 years ; that of the males was 57.8, and that of the females was 53.6 (p<0.05) . The affected nerve was unilateral in 400 patients (the right in 132 cases, and the left in 268) and bilateral in 42. The number of patients with postoperative RLNP was 181 (41%) . We also compared the results obtained from 1976 to 1985 with those from 1986 to 1996. The number of patients from 1976 to 1985 was 201 (males : 102, females : 99), while that from 1986 to 1996 was 241 (males : 146, females : 95) . There was a significant increase in male patients (p<0.05) . The number of patients with postoperative RLNP from 1976 to 1985 was 55 (27.4%), while that from 1986 to 1996 was 126 (52.3%) . There was a significant increase in patients with postoperative RLNP (p<0.01), which was caused by an increase in the number of cases who had had surgery for thyroid tumors and esophageal cancer. On the other hand, there was a significant decrease in patients due to chest diseases (p<0.05) . The ratio of idiopathic RLNP from 1986 to 1996 was lower than that from 1976 to 1985, but the difference was not statistically significant.

Total thyroidectomy for benign thyroid disease

Background: The goal of this study was to evaluate the safety and efficacy of total thyroidectomy performed for benign thyroid disease. Methods: A total of 106 consecutive patients undergoing total thyroidectomy for benign disease from October 1982 to July 1995 were reviewed. The 33 men and 73 women had an average age of 46 years (range, 16 to 82 years). Indications for total thyroidectomy were a thyroid nodule with the history of head and neck radiation in 36 patients, bilateral thyroid nodules in 35, needle biopsy of a follicular neoplasm or frozen section diagnosis of a possible malignancy in 18, and toxic goiter in 17. Total thyroidectomy was performed as the primary operation in 98 patients, and 8 patients had a completion reoperation for recurrent disease. Results: Pathology findings revealed benign nodular goiter in 49 patients, follicular adenoma in 26, hyperplasia in 19, and Hashimoto's thyroiditis in 12. Postoperative hemorrhage requiring operative hemostasis occurred in two patients (1.9%). Two patients had unilateral recurrent laryngeal nerve (RLN) palsy before operation (1.9%). Three patients had unilateral postoperative RLN palsy (2.8%). Two cases resolved in 3 and 4 months. The only permanent RLN injury occurred in a patient reoperated for a compressive goiter. Early postoperative hypocalcemia (8.0 mg/dl or less) was found in nine patients (8.5%). No patient had permanent hypoparathyroidism at long-term follow-up evaluation. Conclusions: Total thyroidectomy for benign thyroid disease can avoid reoperation for nodular goiter and hyperthyroidism and eliminate any subsequent risk of malignant change in radiated thyroid glands. A low complication rate can be achieved with meticulous surgical technique. Total thyroidectomy can be performed safely for bilateral benign thyroid disease. (Surgery 1998;123:2-7.)