ABSTRACT
Recurrent differentiated thyroid carcinoma can easily be detected by means of ultrasound (US) and thyroglobulin, and often requires further surgical intervention. Revision surgery is often a technical challenge with significant risk of complications, considering the altered anatomy, with a possibility of leaving behind residual neoplasm. Preoperative US-guided tattooing localization has been introduced to reduce and prevent these potential problems during revision surgery. Encouraging results have been reported in the literature. Under US guidance, the lesion is identified and 0.5-2 ml of colloidal charcoal is injected in its proximity using a 23 gauge needle. The extraction is accompanied by injection at constant pressure of charcoal in order to leave a trace of pigment along the path of the needle till the skin. From April 2008 to January 2016 we performed revision surgery in 27 patients for lymph-nodes metastasis in differentiated thyroid cancer, using the technique of preoperative charcoal tattoo localization. Our previous study on the first group of 13 patients published in 2012, reported the preliminary results in terms of success rate and complications. The tolerance of charcoal injection was good for all patients and the procedure was demonstrated to be useful, contributing to the removal of metastatic lesion in 93% of procedures. We have registered minor surgical complications during revision in the central compartment of the neck: Transitory hypoparathyroidism in 2 cases (11%) and transitory vocal cord paresis in 3 cases (16%). Based on these results, preoperative charcoal tattoo localization in revision surgery of the neck for differentiated thyroid cancer recurrence can be considered a safe technique, easy to perform, with low-costs and useful during surgical procedures, providing a significant reduction of iatrogenic damage and risks.
ABSTRACT
OBJECTIVE: This study aimed to analyze the autonomic control of heart rate variability (HRV) in subjects receiving chronic l-thyroxine (l-T4) treatment after total thyroidectomy and (131)I therapy for differentiated thyroid carcinoma. METHODS: Blood pressure (BP) and sympatho-vagal activity (evaluated by power spectral analysis (PSA) of time-domain parameters of HRV) were studied in clinostatism and after orthostatism in 24 healthy controls, and in 12 patients taking l-T4 (125-200 mug/day) to maintain serum TSH levels at <0.01 muIU/ml. The study of HRV by PSA is a non-invasive method of analyzing sympatho-vagal control of HRV by quantifying high-frequency (HF) (0.15-0.4 Hz) and low-frequency (LF) (0.04-0.15 Hz) powers. RESULTS: Patients on L-T4 treatment had undetectable TSH levels, serum free T4 (fT4) above the normal range or at the upper limit in one case, and normal free tri-iodothyronine (fT3) levels. Heart rate and R-R intervals were not different in the two groups, both in clinostatism and in ortostatism. Systolic and mean BP were higher in patients than in controls and were inversely correlated with actual serum fT4 levels. During clinostatism, thyroid patients showed significantly lower LF power (P = 0.035), LF/(LF + HF) (P = 0.008) and LF/HF (P = 0.01) than controls. When patients moved from lying to standing, there was a significantly different decrease in orthostatic LF power (P = 0.001), LF/(LF + HF) (P = 0.044) and LF/HF (P = 0.047) versus controls. CONCLUSIONS: Changes in autonomic control of HRV, characterized by decreased sympathetic activity and impaired sympatho-vagal balance with preserved vagal tone, are detectable in patients with hyperthyroxinemia due to suppressive l-T4 therapy and increased systolic and mean, but not diastolic, BP.
