Methods
The research is a retrospective study in which data were analyzed for patients surgically treated for GD at the Centre for Endocrine Surgery, Clinical Centre Serbia in the period 1996–2010. In this period a total of 1432 patients were operated for GD. Among the operated patients there were significantly more women, 1211 (84.6%), while there were 221 men (15.4%); which roughly corresponds to a ratio of 6 to 1. The average age of the patients was 34.8 years (21 to 76 years).
All patients had previously been treated with thyrostatic therapy (carbimazole, thiamazole, propylthiouracil) for a period of 2 to 7 years, as well as with β-adrenergic blockers. There were no patients who were previously treated with radioiodine.
The diagnosis was based on clinical presentation, thyroid hormones (T3, T4, TSH), and values of TSH-receptor antibodies (increase above 1.0 IU/L).
Preoperatively, all patients achieved an euthyroid state and were afterwards reviewed by an anaesthesiologist, cardiologist and otorhinolaryngologist. All patients were treated preoperatively with Lugol's solution of iodine with 3–5 drops of iodine/a day for 2–3 weeks before surgery.
The study has been performed in accordance with the Declaration of Helsinki. Ethical approval for our study was obtained from institutional ethical committee of Clinical Centre Belgrade, Serbia. All patients signed a consent form for the surgical procedure which comprises their consent for the storage and use of their data.
Data analyzed were patient sex, age, indications for surgery, type of surgery, the incidence of carcinoma and microcarcinoma and the frequency of complications (postoperative permanent hypoparathyroidism, unilateral recurrent nerve paralysis and postoperative hematomas), as well as the occurrence of associated complications with the same patient.
Postoperative permanent hypoparathyroidism was confirmed 3 months after surgery and was defined by the values of the parathyroid hormone below the lower limit of the normal range of hormones (normal parathyroid hormone from 10.0 to 65.0 pg/mL).
Unilateral recurrent nerve paralysis was confirmed by the existence of unilateral vocal cord paralysis.
Postoperative hematoma was diagnosed over a period of 24 hours after surgery and required revision of haemostasis.
The analysis used data from the medical records, operational protocols, reports on the histopathological examinations and check-ups.
Obtained data (incidence of complications and the incidence of associated complications), are presented in tables with absolute numbers and the percentages of corresponding structure in relation to the type of applied surgical methods. Comparison between the frequencies was performed with nonparametric Fisher's test. Statistical analysis was performed with software package SPSS version 18 (SPSS Inc., Chicago, Illinois, USA) at the level of statistical significance of p < 0.05.