Eun Jung Kong

(18F)Fluoro-deoxy-D-glucose uptake of knee joints in the aspect of age-related osteoarthritis: a case-control study

BackgroundThis study investigated 18F-fluorodeoxyglucose (18F-FDG) uptake at knee joints for determination of metabolic alteration in association with the advance of age and joint degeneration such as osteoarthritis (OA).MethodsA total of 166 knees from 83 healthy persons who presented for routine health examination and positron emission tomography-computed tomography (PET/CT) were enrolled in this study. History of knee OA and joint symptoms and signs were reviewed. The maximum standardized uptake values (SUVmax) of cartilage and mean SUV (SUVmean) between the epiphyseal plates of femur and tibia were evaluated at knee joints. Assessment of radiological bony changes was performed using the Kallgren-Lawrence (K/L) grading system with reconstructed CT images of the knee. The joint symptoms and signs were counted and used for diagnosis of clinical and radiological OA of the knee.ResultsThe SUVmean of the knee joints showed a remarkable increase with aging in females (r = 0.503, p < 0.01). Remarkable changes of SUVmean were observed with history of OA (p < 0.01). The SUVmean of joint and the intra-articular SUVmax showed higher values in clinical and radiological OA than in normal joints (p < 0.01). Joint-SUVmean showed significant correlation with OA severity graded according to K/L score (p < 0.05). The intra-articular SUVmax showed a significant increase in symptomatic joints, indicating OA in correlation with the joint-SUVmean (p = 0.01).ConclusionsThe increasing 18F-FDG uptakes of knee joints showed agreement with aging in females and clinical and radiological knee OA, indicating that the metabolic alterations were consistent with diagnosis and demographic aspect of OA as a surrogate marker for degeneration of the knee in association with aging.

Myocardial Fibrosis in Hypertrophic Cardiomyopathy Demonstrated by Integrated Cardiac F-18 FDG PET/MR

Hypertrophic cardiomyopathy (HCM) is a common condition defined as a diffuse or segmental left ventricular (LV) hypertrophy with a nondilated and hyperdynamic chamber as well as cardiac arrhythmias. Cardiac MR (CMR) imaging is a key modality for evaluation of HCM. In addition to the assessment of LV wall thickness, LV function and aortic flow, CMR is capable of estimation of late gadolinium enhancement (LGE) in affected myocardium which has been shown to have a direct correlation with incidence and severity of arrhythmias in HCM. In patients with HCM, LGE on CMR is presumed to represent intramyocardial fibrosis. Meanwhile, F-18 FDG myocardial PET has been sporadically studied in HCM, mostly for evaluation of the metabolic status of a hypertrophic myocardial segment, especially after interventions or to demonstrate partial myocardial fibrosis. We presented here the case of a 25-year-old male patient referred for simultaneous F-18 FDG cardiac PET/MR for the evaluation of septal hypertrophy. The PET/MR revealed myocardial fibrosis in the septum associated with FDG-defect and LGE.

Kikuchi-Fujimoto disease mimicking malignant lymphoma with 2-[(18)F]fluoro-2-deoxy-D-glucose PET/CT in children.

Purpose Kikuchi-Fujimoto disease (KFD) is a benign disease, which is characterized by a cervical lymphadenopathy with fever, and it often mimics malignant lymphoma (ML). 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) is a powerful imaging modality for the diagnosis, staging and monitoring of ML, with the limitations including the nonspecific FDG uptake in infectious or inflammatory processes. This study compared clinical manifestations and PET/CT findings between KFD and ML patients. Methods We retrospectively reviewed the medical records of 23 patients with KFD and 33 patients with ML, diagnosed histopathologically, between January 2000 and May 2013 at the Department of Pediatrics, Yeungnam University Medical Center. Among them, we analyzed the clinical manifestations, laboratory findings and characteristics, and the amount of 18F-FDG uptake between 8 KFD and 9 ML patients who had 18F-FDG PET/CT. Results The 18F-FDG PET/CT maximum standardized uptake values (SUVmax) ranged from 8.3 to 22.5 (mean, 12.0) in KFDs, and from 5.8 to 34.3 (mean, 15.9) in MLs. There were no significant differences in SUVmax between KFDs and MLs. 18F-FDG PET/CT with ML patients showed hot uptakes in the extranodal organs, such as bone marrow, small bowel, thymus, kidney, orbit and pleura. However, none of the KFD cases showed extranodal uptake (P<0.001). 18F-FDG PET/CT findings of KFD with nodal involvement only were indistinguishable from those of ML. Conclusion Patients who had extranodal involvement on PET/CT were more likely to have malignancy than KFD.

Clinical outcomes of low-dose and high-dose postoperative radioiodine therapy in patients with intermediate-risk differentiated thyroid cancer.

Purpose Recent studies have suggested that a low dose (LD) of radioiodine (RAI) is sufficient to treat differentiated thyroid cancer (DTC) even in patients with intermediate risk. However, these studies evaluated the efficacy of RAI therapy, irrespective of the results of the whole-body scan (WBS). The aim of the present study was to evaluate the response to LD and high-dose (HD) RAI therapy using two different criteria (with and without WBS results) and the reclassification system according to the revised 2015 guidelines of the American Thyroid Association in Korean intermediate-risk DTC patients. In addition, we evaluated the long-term clinical outcomes of treatment with LD and HD RAI. Materials and methods In total, 204 intermediate-risk DTC patients who underwent postoperative RAI therapy at two tertiary referral hospitals from 2003 to 2004 were enrolled in the present retrospective study. One hundred and twenty-four patients were treated with 3.7 and 5.55 GBq (HD) of RAI in one center and 80 patients were treated with 1.11 GBq (LD) in the other center. The success rate of RAI therapy was assessed with or without the inclusion of WBS results in the analysis. In addition, the response to therapy during the first 2 years of follow-up after the initial RAI therapy was categorized according to the reclassification system of 2015 American Thyroid Association guidelines as excellent response, indeterminate response, biochemical incomplete response, or structural incomplete response. Recurrence was defined as a newly detected cytologically or pathologically confirmed lesion. Results There were no significant differences between the success rates of the HD and LD groups irrespective of the inclusion of WBS results in the analysis (with WBS: 54.84 vs. 45.0%, P=0.23; without WBS: 60.48 vs. 62.5%, P=0.77). The response to HD and LD RAI therapy was excellent in 54.84 and 45.0% of the patients, respectively; indeterminate in 34.68 and 30.0% of the patients, respectively; biochemical incomplete in 4.03 and 13.75% of the patients, respectively; and structural incomplete in 6.45% and in 11.25% of the patients, respectively (P=0.04). In particular, the biochemical or structural incomplete response rate was lower in patients treated with HD than in patients treated with LD (HD, 10.48%; LD, 25.0%, P=0.01). At the last follow-up (HD, median 11 years; LD, median 10 years), patients who achieved an excellent response showed no evidence of disease. After the initial RAI therapy, eight patients in the HD group and 18 patients in the LD group who achieved either indeterminate response or biochemical incomplete response received additional RAI therapy. Seven patients (indeterminate response in five patients; biochemical incomplete response in two patients) in the HD group and seven patients (indeterminate response in five patients; biochemical incomplete response in two patients) in the LD group showed recurrences. Conclusion LD RAI therapy after thyroidectomy appears to be insufficient in Korean DTC patients with intermediate risk. The patients in the LD group predominantly showed biochemical or structural incomplete response to initial RAI therapy and additional RAI therapy was required.

Measurement of SUVs-Maximum for Normal Region Using VOI in PET/MRI and PET/CT

The purpose of this research is to establish an overall data set associated with the VOI (Volume of Interest), which is available for simultaneous assessment of PET/MRI and PET/CT regardless of the use of contrast media. The participants as objects of this investigation are 26 healthy examinees in Korea, SUV (standardized-uptake-value)s-maximum evaluation for whole-body F-18 FDG (fluorodeoxyglucose) PET/MRI image using VOI of normal region has exhibited very significant difference to that for whole-body F-18 FDG PET/CT image (significant probability value (P) < 0.0001). However, there appeared high correlation between them in view of statistics (R-square (R) > 0.8). It is shown that one needs to decide SUVs-maximum for PET/MRI with the reduction of 25.0~26.4% from their evaluated value and needs to decide with the reduction of 28.8~29.4% in the same situation but with the use of contrast media. The use of SUVLBM-maximum (SUVLean Body Mass-maximum) is very advantageous in reading overall image of PET/CT and PET/MRI to medical doctors and researchers, if we consider its convenience and efficiency. We expect that this research enhances the level of the early stage accurate diagnosis with whole-body images of PET/MRI and PET/CT.

Prognostic value of preoperative 18f-fdg Pet/ct in papillary thyroid cancer patients with a high metastatic lymph node ratio: a multicenter retrospective cohort study.

Objective Metastatic lymph node ratio (MLNR) is a known significant predictor of disease-free survival in differentiated thyroid cancer. The authors investigated the ability of preoperative fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT to predict recurrence after surgery with radioactive iodine therapy considering MLNR. Patients and methods A total of 274 patients who underwent preoperative PET/CT and surgery with radioactive iodine therapy were enrolled. The tumor-to-liver uptake ratio on PET/CT was calculated by dividing the maximum standardized uptake value of a primary lesion by the mean standardized uptake value of the normal liver. High 18F-FDG uptake was defined as tumor-to-liver uptake ratio more than the median cutoff value (2.1). MLNR was calculated by dividing the number of metastatic lymph nodes (LNs) by the number of cervical LNs removed. A high MLNR was also defined as one more than a threshold value (0.4), identified by plotting Kaplan–Meier survival curves and comparing them using the log-rank test. The prognostic significances of clinicopathologic variables were analyzed. Results Fifteen (5.5%) patients developed recurrence in the thyroid bed or in cervical LNs. Cox regression analysis showed that a high MLNR was significantly associated with a worse disease-free survival (odds ratio 6.95; 95% confidence interval: 2.36–20.47; P<0.001). A subgroup analysis of 70 patients with a high MLNR showed that only high 18F-FDG uptake was significantly associated with a worse disease-free survival (odds ratio 5.77; 95% confidence interval: 1.22–27.16; P=0.027). Conclusion High 18F-FDG uptake of primary lesion on preoperative PET/CT has selective prognostic value according to the extent of metastatic LNs (MLNR>0.4).

The Changes of Trends in the Diagnosis and Treatment of Diabetic Foot Ulcer over a 10-Year Period: Single Center Study

Background This study aims to describe the trends in the severity and treatment modality of patients with diabetic foot ulcer (DFU) at a single tertiary referral center in Korea over the last 10 years and compare the outcomes before and after the introduction of a multidisciplinary diabetic foot team. Methods In this retrospective observational study, electronic medical records of patients from years 2002 to 2015 at single tertiary referral center were reviewed. Based on the year of first admission, patients were assigned to a group either before or after the year 2012, the year the diabetes team launched. Results Of the 338 patients with DFU, 229 were first admitted until the year 2011 (group A), while 109 were first admitted since the year 2012 (group B). Mean age was higher in group B, and ulcer size was larger than those of group A. Whereas duration of diabetes was longer in group B, glycemic control was improved (mean glycosylated hemoglobin, 9.48% vs. 8.50%). The proportion of minor lower extremity amputation (LEA) was increased, but length of hospital stay was decreased (73.7±79.6 days vs. 39.8±36.9 days). As critical ischemic limb increased, the proportion of major LEA was not decreased. Conclusion Improved glycemic control, multidisciplinary strategies with prompt surgical treatment resulted in reduced length of hospital stay, but these measures did not reduce major LEAs. The increase in critical ischemic limb may have played a role in the unexpected outcome, and may suggest the need for increased vascular intervention strategies in DFU treatment.

Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Findings of Post Traumatic Lymphangioma in a Young Adult Male

The authors report the case of a 34-year-old male, who underwent a fluorine-18 fluoro deoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) scan 7 years after trauma for the evaluation of multifocal masses in the right iliac and right inguinal areas. CT findings showed multifocal low density masses and 18F-FDG PET revealed slightly increased uptake (maximum standardized uptake value [SUVmax] 3.1). These findings did not exclude the possibility of a benign or malignant lesion. To achieve differential diagnosis, partial surgical excision was performed and a pathologic examination subsequently revealed lymphangioma. Here, the authors describe the 18F-FDG PET/CT findings of a rare case of lymphangioma resulting from trauma.

Primary Hepatic Actinomycosis Mimicking Hepatic Malignancy with Metastatic Lymph Nodes by F-18 FDG PET/CT

Actinomycosis is a rare infection caused by gram-positive, anaerobic bacteria. It commonly manifests as a cervicofacial disease, but is also encountered as thoracic and abdominopelvic forms [1]. Hepatic involvement is usually secondary to abdominal actinomycosis infection. Primary hepatic actinomycosis accounts for 5 % of all cases of actinomycosis [2] and can be considered when there is no sign of primary involvement of the abdominal area or elsewhere in the body [3]. Symptom onset is typically subacute and the disease follows a chronic and indolent course. Usual clinical findings include fever, right upper quadrant pain, and weight loss [4]. Actinomycosis may appear as a solid enhancing mass on CT images [3–5], and hepatic actinomycosis may mimic a primary or metastatic tumor clinically or radiologically [3, 6]. These lesions are called inflammatory pseudotumors and cannot be differentiated from malignant tumors by radiological examination alone [3]. Definitive diagnosis is based on the demonstration of sulfur granules in a biopsy specimen or of aspirated pus and Gram-stained smears of anaerobic cultures [3, 5]. A 27-year-old man was admitted with a 3-day history of fever and weight loss (14 kg/ 2 months) (Fig. 1). Laboratory tests showed mild anemia; hemoglobin 119 g/L, elevated white blood cell count of 23,060/mm (83.1 %), AST 33 U/L, ALT 45 U/L, and γ-GT 155 U/L. CA 19–9 was 3.4 μ/mL and CEA was 1.0 ng/mL.

F-18 FDG PET/MRI findings of primary breast lymphoma in two cases:FDG PET/MRI findings of primary breast lymphoma

We present the integrated positron emission tomography (PET)/magnetic resonance imaging (MRI) findings of diffuse large B-cell lymphoma involving the breast in two women. They were admitted with palpable breast masses. PET/MRI revealed high (18)F-fluorodeoxyglucose (FDG) uptake in multinodular enhancing masses without other FDG-avid foci. Diffusion-weighted imaging showed restricted water diffusion and dynamic contrast MRI showed rapid increase and washout kinetics. High FDG accumulation in tumor is related to washout kinetics. We present the usefulness of integrated PET/MRI for lesion characterization and total body staging in breast lymphoma.