Ji Hwa Ryu

Core Needle Biopsy of the Thyroid: 2016 Consensus Statement and Recommendations from Korean Society of Thyroid Radiology

Core needle biopsy (CNB) has been suggested as a complementary diagnostic method to fine-needle aspiration in patients with thyroid nodules. Many recent CNB studies have suggested a more advanced role for CNB, but there are still no guidelines on its use. Therefore, the Task Force Committee of the Korean Society of Thyroid Radiology has developed the present consensus statement and recommendations for the role of CNB in the diagnosis of thyroid nodules. These recommendations are based on evidence from the current literature and expert consensus.

The prevalence and features of thyroid pyramidal lobe, accessory thyroid, and ectopic thyroid as assessed by computed tomography: a multicenter study.

BACKGROUND AND PURPOSE Understanding the computed tomography (CT) characteristics of the pyramidal lobe and other thyroid variations and detecting them accurately using preoperative neck CT will minimize unnecessary remnant thyroid tissue after total thyroidectomy in patients with thyroid cancer. The purpose of the present study was to assess the frequency, location, and size of the pyramidal lobe and other thyroid variations using a large-scaled, multicenter study. METHODS Neck CT scans for 200 patients were selected from 11 institutions; a total of 2200 patients were included in the study. The patients underwent neck CT for the following reasons: trauma, known thyroid malignancy, cervical lymphadenopathy, palpable neck mass, oropharyngolaryngeal malignancy, vocal cord palsy, postchemotherapy CT follow-up, inflammatory or infectious neck lesion, parathyroid abnormality, and patient request. A single radiologist at each institution retrospectively analyzed 200 neck CT scans. Each radiologist investigated the presence, location, length, volume, and upper end of the pyramidal lobe and its separation or continuity with the main thyroid gland as well as the presence, location, length, and volume of the accessory or ectopic thyroid using a picture archiving and communication system. RESULTS A pyramidal lobe was present in 44.6% (981/2200) of the patients. The prevalence for the pyramidal lobe at the participating institutions ranged from 28.0% to 55.0% (mean, 44.6%). Pyramidal lobes originating from the left side of the thyroid were most common, and the number of pyramidal lobes showing separation from the main thyroid gland was 90 (9.2%). The mean anteroposterior diameter, transverse diameter, and length of the pyramidal lobe were 2.3, 5.9, and 20.8 mm, respectively. Among both men and women, the most common level of the upper end of the pyramidal lobes was the thyroid cartilage, but there was a significant difference in the frequency of the pyramidal lobe between males and females (p<0.0001). The rate of the pyramidal lobe detection in the 2-mm-slice-thickness group was higher than those in the 2.5- and 3-mm groups (p=0.0003). CONCLUSION Neck CT is useful for detecting the presence, size, configuration, and location of the pyramidal lobe and other thyroid variations.

Low-dose CT for patients with clinically suspected acute appendicitis: optimal strength of sinogram affirmed iterative reconstruction for image quality and diagnostic performance

Background As there is increased concern over the radiation exposure particularly in adolescents and young adults, computed tomography (CT) dose reduction is needed in the diagnosis of acute appendicitis. Purpose To evaluate the optimal strength of sinogram affirmed iterative reconstruction (SAFIRE) to obtain the best image quality on a 30-mAs applied low-dose CT (LDCT30mAs) and to compare the diagnostic performances of the LDCT30mAs with different SAFIRE strengths with that of the 100-mAs applied LDCT (LDCT100mAs) for the diagnosis of acute appendicitis. Material and Methods A total of 102 consecutive patients (47 men, 55 women; mean age, 41.2 years; range, 15–82 years) with right lower quadrant pain underwent abdominal-pelvic CT, consisting of arterial phase LDCT100mAs and portal venous phase LDCT30mAs under a fixed 120 kV. LDCT30mAs images were reconstructed separately with five strength levels (S1–S5). Two blinded radiologists recorded scores for the subjective image quality of the LDCT30mAs dataset (S0–S5) and confidence scores for the diagnosis of acute appendicitis on each dataset and LDCT100mAs. CT image noise was measured for each set. Results The study population consisted of 58 patients with confirmed appendicitis and 44 without appendicitis. There was no significant difference in diagnostic performance between LDCT100mAs and LDCT30mAs with any strength for both readers (AUC for reader 1, LDCT30mAs with S0–S5 = 0.97, LDCT100mAs = 0.93, P = 0.0936; for reader 2, LDCT30mAs with S0–S5 = 0.96, LDCT100mAs = 0.97, P = 0.128). The measured noise decreased as the strength increased from S0 to S5 (mean, 20.8 > 17.7 > 15.6 > 13.5 > 11.5 > 9.5, P < 0.0001). However, overall subjective image quality on S3 was better than the other strengths for both readers (S0 < S1 < S2 < S3 > S4 > S5, P < 0.0001). Conclusion Although measured noise declined as SAFIRE strength increased, S3 seems optimal for the best subjective image quality on LDCT30mAs. The diagnostic performance of LDCT30mAs with any strength is comparable to that of LDCT100mAs for the diagnosis of acute appendicitis.

Breast fibromatosis associated with breast implants

Fibromatosis refers to an extra-abdominal desmoid tumor or aggressive fibromatosis. Breast fibromatosis can develop in association with the capsule around a breast implant, although reports of cases of fibromatosis associated with breast implants are rare. As the demand for breast augmentation has increased, it is important to understand the diseases associated with breast implants. In the present report, we describe a case of breast fibromatosis that developed adjacent to a breast implant and demonstrated a relatively well-defined border even though it invaded the surrounding structures. We also explore the specific imaging features for diagnosing breast fibromatosis in association with implants by reviewing previous literature.

Identification of Nasal Bone Fractures on Conventional Radiography and Facial CT: Comparison of the Diagnostic Accuracy in Different Imaging Modalities and Analysis of Interobserver Reliability.

Background There has been no study to compare the diagnostic accuracy of an experienced radiologist with a trainee in nasal bone fracture. Objectives To compare the diagnostic accuracy between conventional radiography and computed tomography (CT) for the identification of nasal bone fractures and to evaluate the interobserver reliability between a staff radiologist and a trainee. Patients and Methods A total of 108 patients who underwent conventional radiography and CT after acute nasal trauma were included in this retrospective study. Two readers, a staff radiologist and a second-year resident, independently assessed the results of the imaging studies. Results Of the 108 patients, the presence of a nasal bone fracture was confirmed in 88 (81.5%) patients. The number of non-depressed fractures was higher than the number of depressed fractures. In nine (10.2%) patients, nasal bone fractures were only identified on conventional radiography, including three depressed and six non-depressed fractures. CT was more accurate as compared to conventional radiography for the identification of nasal bone fractures as determined by both readers (P <0.05), all diagnostic indices of an experienced radiologist were similar to or higher than those of a trainee, and κ statistics showed moderate agreement between the two diagnostic tools for both readers. There was no statistical difference in the assessment of interobserver reliability for both imaging modalities in the identification of nasal bone fractures. Conclusion For the identification of nasal bone fractures, CT was significantly superior to conventional radiography. Although a staff radiologist showed better values in the identification of nasal bone fracture and differentiation between depressed and non-depressed fractures than a trainee, there was no statistically significant difference in the interpretation of conventional radiography and CT between a radiologist and a trainee.

Ultrasound-Guided Fine-Needle Aspiration of Thyroid Nodules Measuring Less than 5 mm: Effects on Specimen Adequacy and Diagnosis

Objective: We aimed to assess the adequacy and efficacy of ultrasound (US)-guided fine-needle aspiration (US-FNA) for small solid thyroid nodules (SSTNs) with the largest diameter <5 mm and compared these according to nodule size. Study Design: Among 656 SSTNs in 569 patients, each SSTN was classified into 1 of 4 groups according to the largest diameter: 1 mm ≤ group A < 2 mm; 2 mm ≤ group B < 3 mm; 3 mm ≤ group C < 4 mm, and 4 mm ≤ group D < 5 mm. We compared the adequacy and efficacy of US-FNA between these groups using histopathologic results as a reference standard. Results: 571 (87.0%) SSTNs were adequately sampled by US-FNA and 200 of these were histopathologically confirmed. The adequacy of US-FNA for SSTNs varied according to the nodule diameter: the smaller the nodule diameter, the lower the diagnostic adequacy. The diagnostic efficacy of US-FNA for SSTNs showed a significant relationship with nodule size: diagnostic efficacy in groups A and B was lower than in groups C and D. Conclusions: The adequacy of US-FNA for SSTNs tended to decrease with decreased nodule size, and diagnostic efficacy of US-FNA for SSTNs with the largest diameter <3 mm was lower than for those ≥3 mm.

Pre-operative Detection of Thyroid Pyramidal Lobes by Ultrasound and Computed Tomography

This study aimed to assess the diagnostic accuracy of pre-operative ultrasound (US) and computed tomography (CT) for detecting thyroid pyramidal lobe (TPL). A single radiologist prospectively performed thyroid US and retrospectively reviewed neck CT to detect TPLs in 135 consecutive patients scheduled for thyroid surgery. The location, size and superior extent of each TPL and its separation or continuity with the main thyroid gland were assessed by thyroid US, neck CT and surgery. The prevalence of TPLs as diagnosed by thyroid US, neck CT and surgery was 58.5% (79/135), 56.3% (76/135) and 60% (81/135), respectively. We compared US and CT detection of TPLs with surgical data to determine their sensitivity (85.2% and 91.4%), specificity (81.5% and 94.4%), positive (87.3% and 96.1%) and negative (78.6% and 87.9%) predictive values and accuracy (83.7% and 92.6%). For detecting TPLs, both neck CT and thyroid US have good diagnostic value, although neck CT is more accurate than thyroid US.

Factors Correlating Outcome in Young Infants With Congenital Muscular Torticollis

Purpose No previous study using follow-up ultrasonography for evaluating the factors associated with the successful regression of congenital muscular torticollis in young infants has been published. This study aimed to assess clinical factors and sonographic features potentially influencing regression in patients with congenital muscular torticollis. Methods From January 2010 to December 2012, 80 infants underwent neck ultrasonography because of clinical suspicion of congenital muscular torticollis. We statistically analysed the correlation between complete resolution and clinicosonographic findings when complete resolution was defined as no visible lesion on follow-up ultrasonography. Results Of the 80 infants, 61 had congenital muscular torticollis and all were followed up by ultrasonography: 1) 34 underwent physiotherapy, and 27 of them (79.4%) revealed complete resolution in follow-up; 2) 27 did not undergo physiotherapy, and 15 of them (55.6%) showed complete resolution. A statistically significant correlation was found between physiotherapy and complete resolution, but not between complete resolution and patient sex; size, volume, and echogenicity of the lesion; and thickness ratio. Conclusions Physiotherapy was the only factor influencing complete resolution in young infants with congenital muscular torticollis.

Postoperative low-dose follow-up computed tomography for patients with stomach cancer: optimal blending ratio of adaptive statistical iterative reconstruction for image quality and diagnostic performance.

Objective To compare the diagnostic performance of adaptive statistical iterative reconstruction applied low-dose computed tomography (CT) (LDCT) with that of the standard-dose CT (SDCT) for local recurrence in patients with stomach cancer. Methods Seventy-nine consecutive patients who had undergone surgical resection for stomach cancer were enrolled. To monitor recurrence, SDCT (120 kilovolt peak [kVp], 200mAs) had been performed. The LDCT (120 kVp, 100 mA s) was taken, and images were reconstructed with 4 levels of adaptive statistical iterative reconstruction (ASIR) blending (0%, 30%, 50%, and 70%). Two blinded radiologists recorded the diagnostic confidence scores for local recurrence in each data set using a 5-point scale. Endoscopic biopsy results served as the reference standard. Receiver operating characteristic (ROC) curve analysis was used to calculate the diagnostic performance. Results The diagnostic performance of LDCT with variable ASIR blending ratios was comparable to that of SDCT (area under ROC curve, 0.727–0.734, 0.687, respectively, P > 0.05). Conclusions The diagnostic performance of ASIR applied LDCT is comparable to that of SDCT.

Desmoplastic fibroma of bone in a toe: radiographic and MRI findings.

Desmoplastic fibroma is a rare benign primary bone tumor that is histologically similar to the soft tissue desmoid tumor. It most often involves the mandible, large long bone or iliac bone. Desmoplastic fibroma in a toe has been extremely rarely reported. Authors report a rare case of desmoplastic fibroma of bone occurring in the distal phalanx of a foot, with descriptions of the radiographic and MRI findings, correlation of the radiologic and pathologic findings, and discussion on the differential diagnosis of the tumor.