title: Microwave Ablation of Symptomatic Benign Thyroid Nodules: Energy Requirement per ml Volume Reduction.
abstract: Purpose:Microwave ablation (MWA) represents a novel thermal ablative treatment of benign thyroid nodules. The aim was to determine the energy required per ml volume reduction in order to match the required energy to the volume-of-interest (VOI).Materials and Methods:25 patients with 25 nodules (6 solid, 13 complex and 6 cystic) were treated by microwave ablation (MWA). The transmitted energy (E) was correlated with the volume change (∆ V) after 3 months. The energy required per ml volume reduction after 3 months was calculated by E/∆ V.Results:MWA resulted in a significant (p < 0.0001) volume reduction (∆ V) with a mean of 12.4 ± 13.0 ml (range: 1.5 - 63.2 ml) and relative reduction of 52 ± 16 % (range: 22 - 77 %). There was a positive correlation between E and ∆ V (r = 0.82; p < 0.05). The mean E/∆ V was 1.52 ± 1.08 (range: 0.4 - 4.6) kJ/ml for all nodules and 2.30 ± 1.5 (0.9 - 4.6), 1.5 ± 0.9 (0.4 - 3.6), 0.75 ± 0.25 (0.4 - 1.2) kJ/ml, respectively, for solid, complex and cystic nodules with a significant difference in E/∆ V for solid and cystic (p < 0.03).Conclusion:The energy required per volume depends on the nodule consistency. Solid nodules require more energy than cystic ones. The estimation of the energy needed per volume-of-interest as an additional parameter should help to avoid under- or overtreatment.Key Points:• The estimated required energy for a volume-of-interest depends on the nodule consistency• In solid nodules a higher energy transmission than in cystic nodules is recommended• The energy transmission as an additional marker to ultrasound is helpful for improving periprocedural monitoringCitation Format:• Korkusuz Y, Kohlhase K, Gröner D et al. Microwave Ablation of Symptomatic Benign Thyroid Nodules: Energy Requirement per ml Volume Reduction. Fortschr Röntgenstr 2016; 188: 1054 - 1060.
authors.affiliation: Department of Nuclear Medicine, Johann Wolfgang Goethe University Hospital, Frankfurt, Germany.
authors.forename: Y
authors.initials: Y
authors.lastname: Korkusuz
authors.affiliation: Department of Nuclear Medicine, Johann Wolfgang Goethe University Hospital, Frankfurt, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Kohlhase
authors.affiliation: Department of Nuclear Medicine, Johann Wolfgang Goethe University Hospital, Frankfurt, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Gröner
authors.affiliation: Department of Nuclear Medicine, Johann Wolfgang Goethe University Hospital, Frankfurt, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Erbelding
authors.affiliation: Radiology, Multiorgan Screening Foundation, Munich, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Luboldt
authors.affiliation: German Center for Thermoablation of Thyroid Nodules, Johann Wolfgang Goethe University Hospital, Frankfurt a. Main, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Happel
authors.affiliation: Department of General and Visceral Surgery, Agaplesion Elisabethenstift Darmstadt, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Ahmad
authors.affiliation: Department of Diagnostic and Interventional Radiology, Johann Wolfgang Goethe University Hospital, Frankfurt, Germany.
authors.forename: T J
authors.initials: TJ
authors.lastname: Vogl
authors.affiliation: German Center for Thermoablation of Thyroid Nodules, Johann Wolfgang Goethe University Hospital, Frankfurt a. Main, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Gruenwald
mesh_terms: D017115:Catheter Ablation / Q000379:methods*; D004307:Dose-Response Relationship, Radiation; D004735:Energy Transfer; D006801:Humans; D008872:Microwaves / Q000627:therapeutic use*; D008875:Middle Aged; D011829:Radiation Dosage; D016606:Thyroid Nodule / Q000473:pathology* / Q000628:therapy*; D016896:Treatment Outcome; D047368:Tumor Burden / Q000528:radiation effects