Double-Needle Lavage for Effective Treatment of Difficult-Aspiration Thyroid Cystic Nodules: A Single-Center Controlled Trial
How does the safety and efficacy of a double-needle lavage (DNL) compare to single-needle aspiration (SNA) in the treatment of thyroid cystic nodules?
DNL demonstrated significantly improved efficacy in terms of material extraction rate and nodule volume reduction compared to SNA. Neither the DNL or SNA group experienced adverse events.
Xiaoyin T, Ping L, Bingwei L, et al. Double-Needle Lavage for Effective Treatment of
Difficult-Aspiration Thyroid Cystic Nodules: A Single-Center Controlled Trial. J Vasc Interv Radiol. 2020;31(10):1675-1681.
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Randomized Controlled Trial
Self-funded or unfunded
Single institution, Renji Hospital, School of Medicine, Shanghai Jiaotong University
Figure. Diagram and ultrasound image of the DNL method. (a) Diagram of the method used in the DNL group; (b) preaspiration; (c) 2 needles inserted in the same ultrasonic plane; (d) immediately postaspiration.
In this single-center randomized controlled trial, 100 patients being treated for thyroid cysts that were identified as having difficult aspiration on initial SNA were randomized to either aspiration via the standard SNA method or the experimental DNL method. Difficult aspiration was defined as either a) complete aspiration not achieved with a single aspiration or b) aspiration of ≤0.5 mL during SNA. Inclusion criteria included symptomatic, ≥2cm fine needle aspiration-confirmed cystic thyroid nodule with absence of malignant tumors. Exclusion criteria included history of cervical radiation, family history of thyroid cancer, severe heart, lung kidney immune system disease, or abnormal coagulation.
40 patients were initially randomized to the SNA group and 60 to the DNL group. The SNA technique involved inserting a single needle into the center of the cystic nodule and aspirating the contents with intermittent sterile water flushes to assist as needed. The DNL technique involved inserting 2 needles simultaneously into the cystic nodule and aspirating with one needle while simultaneously flushing sterile water into the nodule with the other needle. The DNL patients were randomized into 2 subgroups: one with needles both inserted into the center of the cyst in the same ultrasound plane and the other with needles inserted into opposite poles of the cyst. Safety was assessed by measuring complication rates of each technique during the trial. Efficacy was evaluated by both the material extraction rate and reduction rate of total nodule volume after treatment. Operating time of the treatment was also compared.
10 of the 40 patients initially randomized to the SNA group were unable to have more than 1 mL aspirated after 10 minutes of flushing and aspiration attempts; they all opted to switch to the DNL group for further treatment. At the end of the trail, 30 patients underwent SNA and 70 patients underwent DNL. 35 patients each were randomized into the two different DNL technique groups. Volume reduction rate in the DNL group was 95.62 ± 3.66% versus 87.54 ± 7.84% for the SNA group (P < .001). Material extraction rate in the DNL group was 98.45 ± 1.74% versus 91 ± 6.51% in the SNA group (P <.001). DNL procedures took less time than SNA procedures (5.77 ± 1.44 minutes for DNL versus 12.47 ± 3.71 minutes for SNA, P <.001). When both different types of DNL technique were compared, aspiration with both needles at opposite poles yielded lower post-procedure cyst volumes compared to aspiration with both needles in plane at the center of the cyst (0.07 ± 0.08 mL versus 0.22 ± 0.4 mL, P < .05). This did not correspond to a significant difference in material extraction rates except in nodules ≥3 cm (98.71 ± 1.17% versus 96.58 ± 2.35% vs P < .01).
No adverse events or complications, including bleeding, infection, or recurrent laryngeal nerve injury, were noted during the trial.
This prospective trial demonstrated the efficacy of a novel technique, DNL, for the aspiration of cystic nodules that are initially found to be difficult to aspirate. The technique not only proved better at reducing cyst volumes but also proved successful in cases of initial treatment failure with SNA technique. The investigators also evaluated two different DNL techniques and found that inserting the aspiration needles at opposite poles of the cyst may improve material removal, especially in cysts ≥3 cm. Additionally, neither DNL or SNA resulted in adverse events during the trial. While this speaks to the safe nature of both techniques, larger investigations across multiple centers may establish a more comprehensive risk profile. While the novel DNL technique seems promising, this trial did not evaluate clinical significance of the improved material extraction and volume reduction rates. While only symptomatic nodules included in the trial, follow-up data was not captured. Larger multicenter trials that capture symptom reduction in addition to the valuable volumetric data collected herein will help to determine superiority of this promising new aspiration technique.
Jared Edwards, MD
General Surgery Intern (PGY-1)
Department of General Surgery
Naval Medical Center San Diego, San Diego, CA