Feasibility of chest spiral 3D ultrashort echo time magnetic resonance imaging for intrathoracic metastasis work-up in breast cancer.

Background: Chest computed tomography (CT) is routinely performed to evaluate intrathoracic metastasis in patients with breast cancer, but radiation exposure and its potential carcinogenic risks are major drawbacks. Furthermore, pulmonary imaging by magnetic resonance imaging (MRI) is limited by low proton density, rapid signal decay, and sensitivity to respiratory and cardiac motions in lung tissue. Recently, a respiratory gating spiral three-dimensional (3D) ultrashort echo time (UTE) volume interpolated breath-hold examination (VIBE) sequence for lung MRI provides high spatial-resolution images with reasonable scan times. Our objective was to investigate the feasibility of chest spiral 3D UTE VIBE MRI to detect intrathoracic metastasis in breast cancer patients. Methods: This retrospective study of a prospectively collected database was conducted between February and July 2019 after institutional review board approval. All participants provided informed consent for MRI scans. Ninety-three female patients with breast cancer were retrospectively enrolled and underwent preoperative breast MRI, including a chest spiral 3D UTE VIBE sequence. Two chest radiologists evaluated image qualities of intrapulmonary vessels and bronchial wall visibilities, the presence of pulmonary nodules, significant lymph nodes (LNs), and other lung abnormalities on spiral 3D UTE magnetic resonance (MR) images and compared them using chest CT as a reference standard. Results: Intrapulmonary vessels and bronchial walls were visible up to sub-subsegmental and sub-subsegmental levels, respectively, on spiral 3D UTE MR images, and better than fair quality was obtained for artifact/noise and overall image quality for 95.7% and 98.9% of the patients, respectively. The overall detection rate for pulmonary nodules was 62.8% (59/94). Furthermore, 59 of the 81 solid nodules detected by CT were detected by spiral 3D UTE MRI (72.8%), and 31 of the 33 solid nodules (≥5 mm in diameter) detected by CT were identified by spiral 3D UTE MRI (93.9%). Significant LNs in the axillary area were similarly detected by spiral 3D UTE MRI and chest CT. Conclusions: Preoperative breast MRI with a chest spiral 3D UTE sequence could be used to evaluate breast cancer and axillary LNs and intrathoracic metastasis simultaneously and offers a potential alternative to chest CT for breast cancer patients without additional radiation exposure.

Obscured Segments of Ruptured Brain Arteriovenous Malformations: Insights from Their Visualization during Emergency Transarterial Embolization.

A ruptured brain arteriovenous malformation (bAVM) presenting with a hematoma may have unseen parts of the shunts in diagnostic angiography in the acute phase, which may lead to innate incomplete evaluation for the whole angioarchitecture of the bAVM. Even though it is generally accepted that the nidus of a ruptured bAVM may be underestimated in angiography during the acute phase due to hematoma compression, documentation of the underestimated parts has not been described in the literature. The authors report 2 cases of ruptured bAVMs in which the obscured segments were cast with liquid embolic material, which suggests a potential presence of obscured segments in bAVMs.

Usefulness of cone-beam computed tomography to predict residual stenosis after carotid artery stenting.

OBJECTIVES: The long-term durability of carotid artery stenting (CAS) may be determined by various factors; however, residual stenosis is a known risk factor for in-stent restenosis. The authors of this article utilized cone-beam computed tomography (CBCT) in angiosuite to investigate plaque features affecting the character and quality of stent expansion after CAS. METHODS: Forty-two CAS cases with both pre- and post-CAS CBCT evaluations were included in this retrospective analysis. Five features derived from pre-CAS images were tested: (1) eccentricity, (2) overballoon, (3) maximum plaque thickness, (4) calcification barrier, and (5) stenotic degree. For post-CAS CBCT, stent configuration was assessed if the stent was expanded and oval or round in shape as well as outward or inward in orientation. Variables were tested if they were associated with oval expansion, outward expansion, and 20% residual stenosis after CAS. RESULTS: Oval or outward expansion is directly related to residual stenosis. The oval expansion was associated with maximum plaque thickness, and outward expansion was associated with the presence of a calcification barrier. Variables related to > 20% residual stenosis were the maximum plaque thickness, calcification barrier, and pre-CAS stenotic degree. CONCLUSIONS: CBCT for carotid stenosis may provide valuable information about plaque features, especially calcification features that may interfere with the angioplasty effect, as well as the characteristics and quality of stent expansion. Residual stenosis > 20% was associated with calcification barrier, maximum plaque thickness, and pre-CAS stenotic degree.

Efficacy of single-session 99.5% ethanol sclerotherapy for incidentally found simple renal cysts.

Simple renal cysts are the most common masses in the kidney. Most are asymptomatic and are incidentally detected on imaging examinations performed for other reasons. This study aimed to compare the results of 40 and 120 minutes ethanol sclerotherapies that were performed in a single session to treat incidentally found simple renal cysts. We retrospectively reviewed 63 renal cysts in 62 patients treated by single session percutaneous ethanol sclerotherapy. Thirty-one patients with 32 cysts underwent a 40 minutes sclerotherapy (group A), and 31 patients with 31 cysts underwent a 120 minutes retention technique (group B). Under ultrasonographic and fluoroscopic guidance, cystic fluid was completely aspirated, and 50% of the aspirated volume was replaced with 99.5% ethanol (a maximum of 100 mL). Imaging follow-up of the patients was performed 3 months after sclerotherapy. The technical success rates were 100% in both groups. Eighteen patients (29.0%) were symptomatic (flank pain or discomfort). Indications of the other patients were large cysts (>5 cm; 46%) and an increment in the diameter on serial studies (25.4%). A significant difference between the 2 groups in terms of age, cyst diameter, volume of aspirated fluid, volume of injected ethanol, and percentage of reduction in cyst diameter (P > .05) was not found. After treatment, flank pain or discomfort resolved in 17 of 18 (94.4%) symptomatic patients. One patient complained of persistent flank pain; however, no significant abnormality was detected on post-procedural computed tomography images. There were no other complications after therapy in the 2 groups. Single session ethanol sclerotherapy with a 40 minutes retention technique is an effective, safe, and cost-effective method for the treatment of incidentally found simple renal cysts. Although the procedural time was reduced, there was no significant difference in therapeutic efficacy between the 40 and 120 minutes therapies.

Malignant melanotic nerve sheath tumors in the spinal canal of psammomatous and non-psammomatous type: Two case reports.

BACKGROUND: A malignant melanotic nerve sheath tumor (MMNST), previously known as a melanotic schwannoma, is a rare variant of a peripheral nerve sheath tumor composed of Schwann cells with melanotic differentiation. Only a few reports of spinal MMNST have been reported. CASE SUMMARY: In the first case, a 58-year-old woman presented with a history of low back pain and paresthesia. Magnetic resonance imaging (MRI) and computed tomography (CT) of the lumbar spine revealed an intradural extramedullary mass lesion with amorphous linear calcification. Complete tumor resection was performed and histological examination revealed a psammomatous melanotic schwannoma. In the second case, a 72-year-old man presented with low back pain and paresthesia. MRI of the thoracolumbar spine revealed an intramedullary mass lesion at the T11 vertebral body level. The mass lesion was hypointense on T2WI and hyperintense on T1WI. Tumor resection was performed and the histologic result was melanotic schwannoma. CONCLUSION: MMNST should be considered in the differential diagnosis when calcification or melanin is seen in an intradural spinal tumor.

Imaging Characterization of Non-Rheumatoid Retro-Odontoid Pseudotumors: Comparison with Atlantoaxial Manifestation of Rheumatoid Arthritis.

Backgroundand Objectives: To date, imaging characterization of non-rheumatic retro-odontoid pseudotumors (NRROPs) has been lacking; therefore, NRROPs have been confused with atlantoaxial joint involvement of rheumatoid arthritis (RA). It is important to differentiate these two disease because the treatment strategies may differ. The purpose of this study is to characterize imaging findings of NRROPs and compare them with those of RA. Material and Methods: From January 2015 to December 2019, 27 patients (14 women and 13 men) with NRROPs and 19 patients (15 women and 4 men) with RA were enrolled in this study. We evaluated various imaging findings, including atlantoaxial instability (AAI), and measured the maximum diameter of preodontoid and retro-odontoid spaces with magnetic resonance imaging (MRI) and computed tomography (CT). Results: Statistical significance was considered for p < 0.05. AAI was detected in eight patients with NRROPs and in all patients with RA (p < 0.0001). Seventeen patients with NRROPs and six patients with RA showed spinal cord compression (p = 0.047). Compressive myelopathy was observed in 14 patients with NRROPs and in 4 patients with RA (p = 0.048). Subaxial degeneration was observed in 25 patients with NRROPs and in 9 patients with RA (p = 0.001). Moreover, C2-3 disc abnormalities were observed in 11 patients with NRROPs and in 2 patients with RA (p = 0.02). Axial and longitudinal diameter of retro-odontoid soft tissue and preodontoid and retro-odontoid spaces showed significant differences between NRROP and RA patients (p < 0.0001). Furthermore, CT AAI measurements were differed significantly between NRROP and RA patients (p < 0.05). Conclusions: NRROPs showed prominent retro-odontoid soft tissue thickening, causing compressive myelopathy and a high frequency of subaxial and C2-3 degeneration without AAI.

Usefulness of Contrast-Enhanced CT in a Patient with Acute Phlegmonous Esophagitis: A Case Report and Literature Review.

Acute phlegmonous esophagitis is a very rare, life-threatening form of esophagitis, characterized by diffuse bacterial infection and pus formation within the submucosal and muscularis layers of the esophagus. We describe a case in which contrast-enhanced chest CT was useful for evaluating the severity of phlegmonous esophagitis, which was overlooked and underestimated by endoscopy.

Emphysema Quantification Using Ultra-Low-Dose Chest CT: Efficacy of Deep Learning-Based Image Reconstruction.

Background and Objectives: Although reducing the radiation dose level is important during diagnostic computed tomography (CT) applications, effective image quality enhancement strategies are crucial to compensate for the degradation that is caused by a dose reduction. We performed this prospective study to quantify emphysema on ultra-low-dose CT images that were reconstructed using deep learning-based image reconstruction (DLIR) algorithms, and compared and evaluated the accuracies of DLIR algorithms versus standard-dose CT. Materials and Methods: A total of 32 patients were prospectively enrolled, and all underwent standard-dose and ultra-low-dose (120 kVp; CTDIvol < 0.7 mGy) chest CT scans at the same time in a single examination. A total of six image datasets (filtered back projection (FBP) for standard-dose CT, and FBP, adaptive statistical iterative reconstruction (ASIR-V) 50%, DLIR-low, DLIR-medium, DLIR-high for ultra-low-dose CT) were reconstructed for each patient. Image noise values, emphysema indices, total lung volumes, and mean lung attenuations were measured in the six image datasets and compared (one-way repeated measures ANOVA). Results: The mean effective doses for standard-dose and ultra-low-dose CT scans were 3.43 ± 0.57 mSv and 0.39 ± 0.03 mSv, respectively (p < 0.001). The total lung volume and mean lung attenuation of five image datasets of ultra-low-dose CT scans, emphysema indices of ultra-low-dose CT scans reconstructed using ASIR-V 50 or DLIR-low, and the image noise of ultra-low-dose CT scans that were reconstructed using DLIR-low were not different from those of standard-dose CT scans. Conclusions: Ultra-low-dose CT images that were reconstructed using DLIR-low were found to be useful for emphysema quantification at a radiation dose of only 11% of that required for standard-dose CT.

Tracheal Glomus Tumor: A Case Report with CT Imaging Features.

BACKGROUND AND OBJECTIVES: Glomus tumors are rare benign tumors. The majority of them affect the skin the most and are rarer in the trachea, where the glomus bodies may not be present. Only scarce reports of tracheal glomus tumors have been reported solely with case reports of relevant articles. MATERIALS AND METHODS: A 53-year-old man, with a free previous medial history, presented to our hospital with tracheal mass which was incidentally found. He did not complain of any specific symptoms associated with the tracheal tumor. The contrast-enhanced chest computed tomography (CT) revealed an avid enhancing nodular lesion, which is similar to blood vessels, in the trachea, 3 cm above the carina level without definite airway obstruction. RESULTS: Successful tracheal resection and end-to-end anastomosis were performed on the patients; therefore, the final post-operative pathologic findings revealed a benign tracheal glomus tumor. The follow-up CT scan four months after operation showed complete removal of the tumor. CONCLUSION: Tracheal glomus tumors, even rare entities, could be considered as a differential diagnosis if a highly enhancing mass appears on CT images.

Successful management of bilateral internal carotid artery fusiform giant aneurysms in a patient with intimal fibroplasia using multiple flow diverters: With long-term imaging follow up.

The authors report a rare case of sequentially developed bilateral internal carotid artery (ICA) fusiform giant aneurysms in a patient with pathologically confirmed intimal fibroplasia. Both ICA fusiform aneurysms were treated with multiple flow diverter insertion and were well-managed over the past 5.5 years of follow-up. The development of aneurysms in this rare disease entity appears to be a lifelong process based on the authors' observations in serial angiographic follow-up studies. Reconstruction therapy using flow-diverting stents in this unique condition may be a safe and effective treatment modality.

Role of digital tomosynthesis in the context of tuberculosis contact investigation: comparisons with digital radiography.

BACKGROUND: Chest radiography value as a screening tool in those exposed to pulmonary tuberculosis (TB) is reduced by its lower sensitivity to detect small intrapulmonary lesions. PURPOSE: To evaluate the efficacy of digital tomosynthesis (DTS) screening of individuals that had contacted persons with active TB using low-dose computed tomography (CT) as the reference standard methods. MATERIAL AND METHODS: This retrospective, community-based screening study of 90 adults who had been in close contact with a TB case was undertaken at our institution. All individuals underwent clinical evaluation, digital radiography (DR), DTS, and low-dose chest CT. Observers assessed and classified DR and DTS images using CT as the reference-standard method. Based on clinical and imaging findings, TB status was classified as normal, latent, minimal, subclinical, and active. Diagnostic performances of DTS and DR for the interpretation of correct diagnosis were calculated. RESULTS: The estimated effective doses for DR, DTS, and low-dose CT were 0.01 mSv, 0.1 mSv, and 0.33 mSv, respectively. TB statuses of the 90 individuals were as follows: 62 latent (68.9%); two subclinical (2.2%); and one minimal (1.1%). The sensitivities, specificities, and accuracies of DTS and DR in the interpretation of correct diagnosis were 75.8%, 100%, 91.1% and 48.5%, 96.5%, 78.9%, respectively. CONCLUSION: DTS appears to be superior to DR for the detection of lung lesions in individuals with TB contacts. DTS can offer a reasonable option for TB contact investigation.

The Relationship between Neural Foraminal Stenosis and Imaging Features of Lumbar Spine MRI in Patients Older Than 60 Years with Lumbar Radiculopathy.

Purpose: To investigate the MRI features associated with neural foraminal stenosis (NFS) in patients older than 60 years with lumbar (L) radiculopathy. Materials and Methods: This study included 133 retrospectively selected patients older than 60 years with lumbar radiculopathy who had undergone a lumbar spine MRI (from January 2018 to April 2018). For L4/L5 and L5/sacral (S)1 levels, NFS was reviewed blindly by two radiologists. Spondylolisthesis, retrolisthesis, disc height loss, disc bulging/herniation/central canal stenosis, ligamentum flavum thickening, and facet hypertrophy were evaluated separately for the NFS and non-NFS groups, and they were compared using univariate and multivariate analyses. Results: The univariate analysis revealed that disc height loss (p = 0.006) was associated with NFS for L4/L5. For L5/S1, both spondylolisthesis (p = 0.005) and facet hypertrophy (p = 0.006) were associated with NFS. The multivariate logistic analysis revealed that disc height loss was associated with NFS for L4/L5 [odds ratio (OR) = 4.272; 95% confidence interval (CI) 1.736-10.514]. For L5/S1, spondylolisthesis (OR = 3.696; 95% CI 1.297-10.530) and facet hypertrophy (OR = 6.468; 95% CI 1.283-32.617) were associated with NFS. Conclusion: Disc height loss was associated with NFS for L4/L5 and spondylJophy were associated with NFS for L5/S1.

Single Center Experience of the Balloon-Stent Technique for the Treatment of Unruptured Distal Internal Carotid Artery Aneurysms: Sharing a Simple and Reliable Tip to Use Scepter-Atlas Combination.

Purpose: The balloon-stent technique (BST) has certain strengths as an assisted technique for the treatment of complex aneurysms. After Atlas release, the BST can be executed without an exchange maneuver of the balloon to the stent-delivery catheter. The purpose of this article is to share our experience with the BST using the Scepter-Atlas combination. Materials and Methods: Device inspection led us to a simple method to avoid failure in loading Atlas to the Scepter. From March 2018 to December 2019, 57 unruptured distal internal carotid artery (dICA) aneurysms were treated with coil embolization; among which, 25 aneurysms in 23 patients were treated with BST. Clinical and angiographic data were retrospectively collected and reviewed. Results: The technical success rate of the Scepter-Atlas combination increased from 50% to 100% after careful inspection. BST angiographic results were comparable to the stent-assisted coil (SAC) group treated during the immediately post-embolization same period (modified Raymond-Roy classification [MRRC] 1 & 2 84% in BST, 96.3% in SAC) and during short-term follow-up (MRRC 1 & 2 95.8% in BST, 88.4% in SAC). A small number of patients showed periprocedural complications, but none had clinical consequences. Conclusion: BST using the Scepter-Atlas combination can provide an effective and safe method for the treatment of dICA aneurysms. Scepters can be used as delivery catheters for Atlas.

Utility of sentinel lymph node biopsy in papillary thyroid microcarcinoma.

Purpose: There are many studies on sentinel lymph node (SLN) biopsy in thyroid carcinoma but SLN biopsy (SLNB) in papillary thyroid carcinoma (PTC) remains open to debate. Therefore in this retrospective study, the usefulness of SLNB in thyroid carcinoma patients who had micro-PTC without cervical lymphadenopathy was assessed. Methods: SLNB was performed in 114 patients who were diagnosed with micro-PTC in a single lobe without palpable or ultrasound-detected lymph node at the tertiary center between January 2012 and December 2013. After SLNB, all patients underwent total thyroidectomy and central neck dissection or thyroid lobectomy and central neck dissection of the single side. Results: SLNs were identified in 112 of 114 patients with 41 positive SLNs and 71 negative SLNs on intraoperative frozen sections. However, eight negative patients were found to be positive in the final pathology. Sentinel node identification rate and false negative value of SLNB were 98.2% and 11.3%, respectively. In the univariate analysis, higher lymph node metastasis was detected in men than in women. Higher detection number of SLN showed higher probability of lymph node metastasis. Conclusion: SLNB may be helpful in papillary thyroid cancer, especially in male patients. Also, it is useful for the staging of nodal status and clearance of persistent disease.

Risk factors affecting the treatment outcome of pediatric foreign body aspiration: significance of time factors.

PURPOSE: The aim of this study was to identify the factors affecting the prognosis of children with foreign body aspiration (FBA) after undergoing rigid bronchoscopy. METHODS: This was a case series with a chart review of 49 children under 3 years of age who underwent rigid bronchoscopy for suspected FBA at a single tertiary institution. RESULTS: The time from symptom onset to hospitalization positively correlated with the total hospitalization time (p < 0.001), postoperative hospitalization time (p = 0.006), and operation time (p = 0.013). The time from symptom onset to operation positively correlated with the total hospitalization time (p < 0.001) and operation time (p = 0.046). The time from hospitalization to operation and the operation time positively correlated with the total hospitalization time (p = 0.026, 0.044) and postoperative hospitalization time (p = 0.049, 0.003). The time from symptom onset to hospitalization positively correlated with the incidence of pneumonia (p = 0.028). CONCLUSION: Rapid hospitalization after symptom onset, rapid surgery after symptom onset, and rapid surgery after hospitalization improve the prognosis of patients with FBA. Further, a short operation time also plays a role in improving patient prognosis.

Clinical and Imaging Findings of Neonatal Seizures Presenting as Diffuse Cerebral White Matter Abnormality on Diffusion-Weighted Imaging without any Structural or Metabolic Etiology.

Purpose: Some patients with neonatal seizures show diffuse, symmetric diffusion-restricted lesions in the cerebral white matter. The aim of this study was to describe clinical and imaging findings of patients with neonatal seizures who had diffuse, symmetric diffusion-restricted lesions without any structural or metabolic etiology. Materials and Methods: A total of 56 neonates aged less than 1 week underwent brain magnetic resonance imaging (MRI) for evaluation of seizures from November 2008 to February 2017. After excluding 43 patients, 13 patients showed diffuse white matter abnormality on diffusion-weighted imaging. Initial and follow-up clinical and MRI findings were analyzed retrospectively. Results: All 13 patients were born at full term. Among the ten patients who underwent a stool test for viruses, six were positive for rotavirus and one for astrovirus. MRI revealed diffuse, symmetric diffusion-restricted lesions distributed along the cerebral white matter, thalami, and midbrain variably. Conclusion: Diffuse, symmetric diffusion-restricted lesions involving the cerebral white matter can be seen in patients with neonatal seizures without any structural or metabolic etiology. Rotavirus is commonly but not exclusively detected in these patients. Nevertheless, viral infection-associated encephalopathy should be considered for patients with characteristic clinical and MRI findings.

Prospective Multicenter Study of the Safety of Gadoteridol in 6163 Patients.

BACKGROUND: The safety of gadolinium-based contrast agents is of fundamental importance. PURPOSE: To determine the frequency and severity of immediate-type adverse reactions to approved doses of gadoteridol in patients referred for routine gadoteridol-enhanced MRI in actual clinical practice settings. STUDY TYPE: Prospective, observational. POPULATION: In all, 6163 subjects were enrolled (mean age: 56.7 ± 15.4 years; range: 6-93 years). FIELD STRENGTH/SEQUENCE: 1.5T and 3.0T. ASSESSMENT: Assessment was of immediate adverse reactions by the investigating radiologist using the MedDRA System Organ Class and preferred term. STATISTICAL TESTS: Summary statistics for continuous variables, descriptive statistics for demographic characteristics. RESULTS: Overall, 19 adverse events occurred in 13 (0.21%) patients, of which 15 in 10 (0.16%) patients were considered related to gadoteridol administration. These events were evenly distributed between male and female subjects and all occurred in adults. Twelve of the 15 related events in eight (0.13%) patients were considered mild in intensity (rapidly self-resolving), while the remaining three events in two patients (0.03%) were considered moderate in intensity. None were of severe intensity and no serious adverse events occurred. DATA CONCLUSION: The rate of immediate-type adverse events following exposure to approved doses of gadoteridol is extremely low, and mostly limited to transient and self-resolving symptoms. LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2020;51:861-868.

Ultra-Low-Dose Neck CT With Low-Dose Contrast Material for Preoperative Staging of Thyroid Cancer: Image Quality and Diagnostic Performance.

OBJECTIVE: Although CT has been used as a complementary diagnostic method for the preoperative diagnosis of thyroid cancer, it has the shortcomings of substantial radiation exposure and the use of contrast material (CM). The purpose of this article is to evaluate the image quality and diagnostic performance of 70-kVp thyroid CT with low volumes of CM versus conventional 120-kVp thyroid CT protocol. MATERIALS AND METHODS: Eighty patients referred for preoperative thyroid CT were randomly divided into two groups (group A: 40 patients, 70 kVp, 60 mL of CM; group B: 40 patients, 120 kVp, 100 mL of CM). Quantitative and qualitative image quality and radiation doses for the two groups were compared using the Mann-Whitney U and chi-square tests. Degrees of agreement between preoperative CT staging and pathologic results were evaluated and compared using the Wald statistic. RESULTS: Calculated signal-to-noise ratios of different anatomic structures, calculated contrast-to-noise ratios, overall image quality, subjective noise, and streak artifacts were not significantly different between the two groups (all p > 0.05), and neither were the accuracies of preoperative CT staging (all p > 0.05). The estimated effective doses were significantly lower in group A (mean [± SD], 0.52 ± 0.14 mSv in group A and 2.28 ± 0.29 mSv in group B; p < 0.001). CONCLUSION: Ultra-low-dose 70-kVp CT with a low volume of CM provides sufficient image quality for preoperative staging of thyroid cancer and substantially reduces the radiation dose compared with standard 120-kVp CT.

Acoustic radiation force impulse imaging of biopsy-proven Kikuchi disease: initial experiences for evaluating feasibility in pediatric patients.

PURPOSE: This study evaluated the feasibility of acoustic radiation force impulse (ARFI) elastography and characterized the sonographic features of lymph nodes (LNs) with Kikuchi disease in pediatric patients. METHODS: Seventy-six cervical LN biopsies were performed for the diagnosis of cervical lymphadenopathy. ARFI imaging was performed, and the characteristic ultrasound features of the biopsied LNs and the contralateral LNs were analyzed. We also reviewed clinical and conventional ultrasonographic findings. RESULTS: On histology, 56 patients were diagnosed with Kikuchi disease. These LNs were large and elongated, with increased perinodal echogenicity and capsular thickening. In 38 of them, ARFI elastography was performed, and the median shear wave velocity (SWV) of the biopsied LNs with Kikuchi disease (2.19 m/sec; range, 1.45 to 4.57 m/sec) was higher than of the contralateral LNs (1.72 m/sec; range, 0.95 to 2.65 m/sec; P<0.001). In patients with reactive hyperplasia, the mean SWV of the biopsied LNs (2.00 m/sec; range, 1.49 to 2.26 m/sec) was higher than that of the contralateral LNs (1.55 m/sec; range, 1.21 to 2.32 m/sec; P=0.031). CONCLUSION: The SWV of LNs with Kikuchi disease was significantly higher than that of the contralateral LNs. Morphologically, LNs with Kikuchi disease showed an enlarged, elongated, and oval shape, increased perinodal echogenicity, and capsular thickening. In addition to the conventional ultrasonographic findings, the application of ARFI is feasible even in pediatric patients for the evaluation of cervical lymphadenopathy.