Recurrent medullary thyroid carcinoma treated with percutaneous ultrasound-guided radiofrequency ablation:A case report

BACKGROUND Treatment for neck lymph node metastases after adequate initial surgery in medullary thyroid carcinoma(MTC)has been controversial.Ultrasound(US)-guided radiofrequency ablation(RFA)has been widely used in recurrent welldifferentiated thyroid carcinoma.Here,we report for the first time the use of RFA in a patient with recurrent MTC.CASE SUMMARY We report the case of a 56-year-old woman with cervical lymph node metastases of MTC.Four years previously,she had undergone a total thyroidectomy and neck lymph node dissection.A neck US revealed many enlarged nodes during the follow-up period.Moreover,the serum calcitonin jumped to 198.17 pg/mL,which strongly indicated the recurrence of MTC.Subsequently,two metastatic lymph nodes were confirmed by US-guided fine-needle aspiration-cytology and fineneedle aspiration-calcitonin,and then the patient was treated with RFA.Four months later,the neck US and a contrast-enhanced US showed obvious shrinkage in the ablation zones,and the serum calcitonin dropped to 11.80 pg/mL.CONCLUSION This case suggests that RFA may be an effective and safe treatment for local recurrent MTC.

Photothermal nonlinear scattering of shell-isolated gold nanoparticles and applications in super-resolution imaging

In this Letter,we report on the investigations of nonlinear scattering of plasmonic nanoparticles by manipulating ambient environments.We create different local thermal hosts for gold nanospheres that are immersed in oil,encapsulated in silica glass and also coated with silica shells.In terms of regulable effective thermal conductivity,silica coatings are found to contribute significantly to scattering saturation.Benefitting from the enhanced thermal stability and the reduced plasmonic coupling provided by the shell-isolated nanoparticles,we achieve super-resolution imaging with a feature size of 52 nm(λ/10),and we can readily resolve pairs of nanoparticles with a gap-to-gap distance of 5 nm.

Coexisting sonographic features of"tumor neovascularization-like pattern"and"echogenic areas"in thyroid nodules:diagnostic performance in prediction of papillary carcinoma

To the Editor:Many well-studied sonographic features have been used clinically to evaluate thyroid nodules for malignancies.Sonographic grayscale features proposed by the American College of Radiology Thyroid Imaging,Reporting and Data System(TI-RADS)include composition,echogenicity,shape,margin,and echogenic foci.[1]Other features,such as vascularity imaging,have gradually been recognized by sonographers.Sustained angiogenesis results in tumor-specific vasculature compared to normal tissues in the context of architecture and biological behavior.[2]Tumor neovascularization shows abnormal maturation,manifesting irregular sprouting,and branching of angiogenic vessels with disordered coverage of pericytes.Therefore,vascularity is critical for the evaluation of malignancy in thyroid nodules.

A novel compound data classification method and its application in fault diagnosis of rolling bearings

Purpose-The purpose of this paper is to provide a fault diagnosis method for rolling bearings.Rolling bearings are widely used in industrial appliances,and their fault diagnosis is of great importance and has drawn more and more attention.Based on the common failure mechanism of failure modes of rolling bearings,this paper proposes a novel compound data classification method based on the discrete wavelet transform and the support vector machine(SVM)and applies it in the fault diagnosis of rolling bearings.Design/methodology/approach-Vibration signal contains large quantity of information of bearing status and this paper uses various types of wavelet base functions to perform discrete wavelet transform of vibration and denoise.Feature vectors are constructed based on several time-domain indices of the denoised signal.SVM is then used to perform classification and fault diagnosis.Then the optimal wavelet base function is determined based on the diagnosis accuracy.Findings-Experiments of fault diagnosis of rolling bearings are carried out and wavelet functions in several wavelet families were tested.The results show that the SVM classifier with the db4 wavelet base function in the db wavelet family has the best fault diagnosis accuracy.Originality/value-This method provides a practical candidate for the fault diagnosis of rolling bearings in the industrial applications.

New views on ultrasonography in high-flow priapism,with typical cases

Dear Editor,Priapism is an uncommon pathological erection that mainly occurs in adult males between the ages of 20 years and 50 years.1 It is defined as an involuntary erection that persists more than 4 h without any sexual stimulation.2 This article reports two patients with high-flow priapism,which is relatively rare.We propose some new ultrasound features to diagnose this disease.After embolization,we assessed the embolization location and monitored whether there was recanalization in the embolization treatment site following therapy through ultrasonography.These have not been mentioned in the previous literature.

Cylindrical vector beam revealing multipolar nonlinear scattering for superlocalization of silicon nanostructures

The resonant optical excitation of dielectric nanostructures offers unique opportunities for developing remarkable nanophotonic devices.Light that is structured by tailoring the vectorial characteristics of the light beam provides an additional degree of freedom in achieving flexible control of multipolar resonances at the nanoscale.Here,we investigate the nonlinear scattering of subwavelength silicon(Si)nanostructures with radially and azimuthally polarized cylindrical vector beams to show a strong dependence of the photothermal nonlinearity on the polarization state of the applied light.The resonant magnetic dipole,selectively excited by an azimuthally polarized beam,enables enhanced photothermal nonlinearity,thereby inducing large scattering saturation.In contrast,radially polarized beam illumination shows no observable nonlinearity owing to off-resonance excitation.Numerical analysis reveals a difference of more than 2 orders of magnitude in photothermal nonlinearity under two types of polarization excitations.Nonlinear scattering and the unique doughnut-shaped focal spot generated by the azimuthally polarized beam are demonstrated as enabling far-field high-resolution localization of nanostructured Si with an accuracy approaching 50 nm.Our study extends the horizons of active Si photonics and holds great potential for label-free superresolution imaging of Si nanostructures.