Efficacy of Ultrasound-Guided Fine-Needle Aspiration Biopsy in the Diagnosis of Complex Thyroid Nodules

Abstract

Cystic thyroid nodules are considered to be one of the major causes of nondiagnostic and false-negative results on conventional fine-needle aspiration biopsy, thus limiting the potential of this method for the evaluation of complex (solid-cystic) thyroid nodules. Although ultrasound-guided fine-needle aspiration biopsy has emerged as a highly effective diagnostic method for the assessment of nonpalpable and difficult to palpate nodules, its role in complex nodules has not yet been carefully evaluated. In this study, we report the efficacy of ultrasound-guided fine-needle aspiration biopsy in 124 complex nodules in 113 patients. This method proved to be highly effective, yielding a satisfactory specimen for cytological evaluation in 94% of the nodules, suggesting that it is an excellent modality for the evaluation of complex nodules and also for the reevaluation of those nodules with a nondiagnostic result on conventional fine-needle aspiration biopsy.

Ultrasound‐Guided Fine Needle Aspiration Biopsy of Thyroid Nodules Performed in the Office

“…Studies have shown that complex nodules are better evaluated under US guidance with an improved accuracy and sample adequacy rate. 9 Recently, US machines have been incorporated into several specialty clinics other than radiology as a diagnostic tool in the office. Several certification courses are available to provide the physician familiarity with the machine and US mechanics.…”

Clinical complications following thyroid fine‐needle biopsy: a systematic review

“…Intranodular haemorrhage within the cystic part of a complex nodule after fluid aspiration is reported to be even more frequent. 17 However, another study reported no intranodular haemorrhage after fluid aspiration. 47 Haemorrhage is caused by venous extravasation into or around nodules.…”

“…3-5 days before FNB 26,27 Small needle size (25-27G) especially for markedly hypervascular nodules or re-aspiration 28,29 FNC instead of FNA in nodules close to large vessels 30 US guidance, especially in nodules close to large vessels 5,30 Slight stretching of the skin above the nodule 9 Firm pressure to the biopsy site with a sterile gauze pad for 2-3 min after FNB (longer in bleeding diathesis) 1,3,8,28 In case of an increasing haematoma that cannot be stopped by pressure, patients should be advised to report to the emergency department (massive haematomas may occur hours after FNB) 8 In cases of hyperthyroidism or thyroiditis De Quervain's FNB should be delayed until euthyroidism restoration 31,32 In cases of complex nodules, direct biopsy (US-FNB) of the solid part without previous evacuation of the fluid 17 Avoidance of repeat FNB shortly after the initial one 33,34 Acute transient swelling ‡ (1/1) Delayed transient swelling ‡ (1/1) Infection (2/3) Alcohol cleansing and iodine skin prep at biopsy site before FNB 28 Adequate sterile conditions during FNB 35,36 Antibiotics in immunosuppressed patients after FNB (prophylactically) 37 Sterile gel in US-FNB Recurrent laryngeal nerve palsy (0·036-0·9%/2) Small needle size 38 Not penetrating the dorsal site of the nodule 19 Vasovagal reaction (0·5-1·3%/1) Pain Suction release before needle withdrawal or use of non-aspiration technique (FNC) 3,17,28,[39][40][41][42][43] Avoidance an excessive piston-like motion of the needle 21 Avoidance of multiple passes and repeat FNB, if possible 3,28 Needle track sinu...…”

“…27,48 An additional mechanism for haemorrhaging soon after fluid aspiration in cystic/complex nodules is the sudden reduction in intranodular pressure because of fluid evacuation. 17 Severe bleeding diathesis is a relative contraindication to thyroid FNB. 26 Despite the absence of direct evidence, FNB may be performed on a patient taking standard doses of aspirin or anticoagulants ( Table 2).…”

Contributory Factors to Hemorrhage After Ultrasound-Guided Fine Needle Aspiration of Thyroid Nodules with an Emphasis on Patients Taking Antithrombotic or Anticoagulant Medications

“…The most likely mechanism for thyroid hemorrhage after FNA is thought to be venous bleeding into or around the nodules (30,31). Factors that facilitate susceptibility to hemorrhagic complications after US-FNA include straining, hypertension, a sudden reduction in intra-nodular pressure soon after fluid aspiration in a cystic nodule, severe bleeding diathesis, and medication with anticoagulant or antithrombotic (4,6,32).…”