Colon cancer: the 2023 Korean clinical practice guidelines for diagnosis and treatment

Colorectal cancer is the third most common cancer in Korea and the third leading cause of death from cancer. Treatment outcomes for colon cancer are steadily improving due to national health screening programs with advances in diagnostic methods, surgical techniques, and therapeutic agents.. The Korea Colon Cancer Multidisciplinary (KCCM) Committee intends to provide professionals who treat colon cancer with the most up-to-date, evidence-based practice guidelines to improve outcomes and help them make decisions that reflect their patients’ values and preferences. These guidelines have been established by consensus reached by the KCCM Guideline Committee based on a systematic literature review and evidence synthesis and by considering the national health insurance system in real clinical practice settings. Each recommendation is presented with a recommendation strength and level of evidence based on the consensus of the committee.

Hilar Choledochal Cyst Mimicking Biliary Atresia on Hepatobiliary Scintigraphy: a Case Report / 대한핵의학회잡지

Hepatobiliary scintigraphy has been widely used for the differential diagnosis of neonatal cholestasis. Relatively good hepatic uptake with no evidence of excretion into the bowel for up to 24 h is a representative finding of biliary atresia. Hepatobiliary scintigraphy has very high sensitivity and moderate specificity. Here, we report a false-positive case of hepatobiliary scintigraphy in a child with a choledochal cyst, which mimicked biliary atresia.

Simulating dose reduction for myocardial perfusion SPECT using a Poisson resampling method / 대한핵의학회잡지

Purpose@#The purpose of this study was to determine the lowest Tl-201 dose that does not reduce the image quality of myocardial perfusion SPECT (MPS) by Poisson resampling simulation. @*Methods@#One hundred and twelve consecutive MPS data from patients with suspected or known coronary artery disease were collected retrospectively. Stress and rest MPS data were resampled using the Poisson method with 33%, 50%, 67%, and 100% count settings. Two nuclear medicine physicians assessed the image quality of reconstructed data visually by giving grades from − 2 to + 2. The summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) were obtained on the workstation. Image quality grades and semi-quantitative scores were then compared among these resampled images. @*Results@#The proportions of “adequate” image quality were 0.48, 0.75, 0.92, and 0.96 for the groups of images with 33%, 50%, 67%, and 100% data, respectively. The quality of the resampled images was significantly degraded at 50% and 33% count settings, while the image quality was not different between 67 and 100% count settings. We also found that high body mass index further decreased image quality at 33% count setting. Among the semi-quantitative parameters, SSS and SRS showed a tendency to increase with a decline in count. @*Conclusion@#Based on the simulation results, Tl-201 dose for MPS can be reduced to 74 MBq without significant loss of image quality. However, the SSS and SRS can be changed significantly, and it needs to be further verified under the different conditions.

18F-fluorodeoxyglucose PET/CT as an independent predictor for patients with hepatocellular carcinoma combined with major portal vein tumor thrombus

Purpose@#Hepatocellular carcinoma (HCC) patients with major portal vein tumor thrombosis (mPVTT) complications were generally characterized by extremely poor prognoses. The aim of this study was to explore the role of 18F-fluorodeoxyglucose (18F-FDG) PET/CT imaging in predicting HCC complicated by mPVTT. @*Methods@#Five hundred one HCC patients received surgery in our hospital during November 2008 to December 2014, among which 32 patients (6.4%) were diagnosed as HCC complicated by mPVTT. Six cases were excluded for reasons of complex medical conditions, including 2 cases of salvage liver transplantation, 2 cases of re-resection, 1 case of mPVTT combined with inferior vina cava tumor thrombosis, and 1 case of residual portal vein tumor thrombosis. Ultimately, 26 cases were enrolled in this study. The maximal tumor standardized uptake value (SUVmax) was identified as a predictive factor and detected. The univariate and multivariate regression analyses were performed to identify the prognostic factors for recurrence-free survival (RFS) and overall survival (OS) of HCC patients complicated by mPVTT. @*Results@#Our results showed that the median OS was 16 months. The 1-, 3-, and 5-year cumulative OS was 55.6%, 31.7%, and 31.7%, respectively. The multivariate regression analysis revealed that SUVmax ≥ 4.65 was the only independent risk factor for RFS and OS. @*Conclusion@#SUVmax was an independent predictor for RFS and OS of patients suffering from both HCC and mPVTT. L ow SUVmax could serve as an effective factor for selecting candidates with low recurrence risks and for helping with improving patient survival after surgical resection.

18F-fluorodeoxyglucose PET/CT as an independent predictor for patients with hepatocellular carcinoma combined with major portal vein tumor thrombus

Purpose@#Hepatocellular carcinoma (HCC) patients with major portal vein tumor thrombosis (mPVTT) complications were generally characterized by extremely poor prognoses. The aim of this study was to explore the role of 18F-fluorodeoxyglucose (18F-FDG) PET/CT imaging in predicting HCC complicated by mPVTT. @*Methods@#Five hundred one HCC patients received surgery in our hospital during November 2008 to December 2014, among which 32 patients (6.4%) were diagnosed as HCC complicated by mPVTT. Six cases were excluded for reasons of complex medical conditions, including 2 cases of salvage liver transplantation, 2 cases of re-resection, 1 case of mPVTT combined with inferior vina cava tumor thrombosis, and 1 case of residual portal vein tumor thrombosis. Ultimately, 26 cases were enrolled in this study. The maximal tumor standardized uptake value (SUVmax) was identified as a predictive factor and detected. The univariate and multivariate regression analyses were performed to identify the prognostic factors for recurrence-free survival (RFS) and overall survival (OS) of HCC patients complicated by mPVTT. @*Results@#Our results showed that the median OS was 16 months. The 1-, 3-, and 5-year cumulative OS was 55.6%, 31.7%, and 31.7%, respectively. The multivariate regression analysis revealed that SUVmax ≥ 4.65 was the only independent risk factor for RFS and OS. @*Conclusion@#SUVmax was an independent predictor for RFS and OS of patients suffering from both HCC and mPVTT. L ow SUVmax could serve as an effective factor for selecting candidates with low recurrence risks and for helping with improving patient survival after surgical resection.

Computed Tomography (CT) Protocols Associated with Cardiac and Bone Single-Photon Emission Computed Tomography/CT (SPECT/CT) in Korea / 대한핵의학회잡지

Purpose@#Single-photon emission computed tomography/computed tomography (SPECT/CT) is an advanced hybrid nuclear medicine technology that generates both functional and anatomical images in a single study. As utilization of SPECT/CT in Korea has been increasing, the purpose of this study was to survey its application of cardiac and skeletal SPECT/CT imaging for protocol optimization. @*Methods@#We surveyed CT protocols established for cardiac and skeletal SPECT/CT. We searched the guidelines for the CT protocols for SPECT/CT and reviewed the literature recently published. @*Results@#Among 36 hybrid SPECT scanners equipped with four or more multi-channel detector CTs (MDCTs), 18 scanners were used to perform cardiac studies at both very low current CT (30–80 mA; 11.1%) and ultra-low current CT (13–30 mA; 88.9%). Among the 33 canners, very low current (≤ 80 mA) CT or low current CT (80–130 mA) was used in 23.5%, and 41.8% for spine disorders, and in 36.4% or 30.3% for foot/ankle disorders, respectively. In the CT reconstructions, slice thickness of 5 mm for cardiac studies was most commonly used (94.4%); thinner slices (0.6–1.0 mm) for spine and foot/ankle studies were used in 24.2% and 45.5%, respectively. We also reviewed the international guidelines. @*Conclusions@#The results and current recommendations will be helpful for optimizing CT protocols for SPECT/CT. Optimization of SPECT/CT protocols will be required for generating the proper strategy for the specific lesions and clinical purpose.

Recent Survey of Effective Doses of F-18 FDG Torso PET/CT in Korea and the Current Recommendations for CT Protocols of PET/CT / 대한핵의학회잡지

Purpose@#This study aimed to construct a database of the effective doses (ED) from F-18 fluorodeoxyglucose (FDG) torso positron emission tomography/computed tomography (PET/CT) in Korea to provide data that supports the reduction of the CT dose of PET/CT and optimization of PET/CT protocols in Korea. @*Methods@#We investigated data of ED and CT parameters of FDG PET/CT. The data were analyzed by body weight groups. @*Results@#A total of 31 hospitals participated in the survey (99 adults). The mean total EDs (± SD) were 8.77 ± 2.76, 10.93 ± 3.14, and 12.57 ± 3.79 mSv for the 55-, 70-, and 85-kg groups, respectively. The FDG EDs were 4.80 ± 0.98, 6.05 ± 1.15, and 6.89 ± 1.52 mSv, and the CT EDs were 4.00 ± 2.12, 4.88 ± 2.51, and 5.68 ± 2.89 mSv, respectively. Of the enrolled hospitals, 54.5% used ultra-low-dose CT protocols, and their CT ED was significantly lower than low-dose CT group in all groups (2.9 ± 1.0, 3.2 ± 1.1, and 3.3 ± 1.0 mSv vs. 6.6 ± 1.6, 7.2 ± 2.1, and 7.9 ± 2.2 mSv, all p < 0.001, respectively). In the ultra-low-dose CT group, the CT ED with the iterative reconstruction was significantly lower than that of CT without iterative reconstruction in the 55-kg group (2.4 ± 0.9 vs. 3.3 ± 0.9, p = 0.04). @*Conclusions@#These results and current recommendations can be helpful for optimizing PET/CT diagnostic reference level (DRL) and reducing unnecessary PET/CT radiation exposure.

Minimum Standardized Uptake Value from Quantitative Bone Single-Photon Emission Computed Tomography/Computed Tomography for Evaluation of Femoral Head Viability in Patients with Femoral Neck Fracture / 대한핵의학회잡지

PURPOSE@#Bone single-photon emission computed tomography/computed tomography (SPECT/CT) has been widely used for evaluation of femoral head viability in patients with femoral neck fracture. The current study aimed to investigate utility of standardized uptake value (SUV) from quantitative bone SPECT/CT for assessment of femoral head viability.@*METHODS@#From March 2015 to November 2018, quantitative bone SPECT/CT was performed in 9 patients with non-viable femoral head post femoral neck fracture and in 31 controls. Maximum (SUV(max)), mean (SUVmean), and minimum standardized uptake values (SUVmin) were measured over femoral head and neck. Mann-Whitney U test with Bonferroni correction was used to compare SUVs of ipsilateral and contralateral femurs from femoral neck fracture patients with those of control femurs.@*RESULTS@#As for femoral head viability, SUV(max) and SUVmean were not significantly decreased in non-viable femoral heads compared to those in controls. Only the SUVmin was significantly reduced in non-viable femoral heads (mean ± standard deviation, 0.57 ± 0.38) than in controls (0.95 ± 0.26, p = 0.006) and contralateral femoral heads (1.36 ± 0.59, p = 0.008). The cutoff SUVmin of 0.61 (g/mL) yielded a sensitivity of 77.8% and specificity of 87.1% for detection of non-viable femoral heads (p = 0.006). Contralateral femoral necks of the femoral neck fracture patients showed significantly higher SUVmean and SUVmin (3.17 ± 1.20 and 1.64 ± 0.63) than those of controls (2.32 ± 0.53 and 1.04 ± 0.27; p = 0.021 and p = 0.002, respectively), which seemed to reflect weight bearing effect or metabolic derangement.@*CONCLUSIONS@#The non-viable femoral heads from the femoral neck fracture showed significantly reduced SUVmin. Quantitative bone SPECT/CT holds promise for objective evaluation of femoral head viability.

Minimum Standardized Uptake Value from Quantitative Bone Single-Photon Emission Computed Tomography/Computed Tomography for Evaluation of Femoral Head Viability in Patients with Femoral Neck Fracture / 대한핵의학회잡지

PURPOSE: Bone single-photon emission computed tomography/computed tomography (SPECT/CT) has been widely used for evaluation of femoral head viability in patients with femoral neck fracture. The current study aimed to investigate utility of standardized uptake value (SUV) from quantitative bone SPECT/CT for assessment of femoral head viability.METHODS: From March 2015 to November 2018, quantitative bone SPECT/CT was performed in 9 patients with non-viable femoral head post femoral neck fracture and in 31 controls. Maximum (SUV(max)), mean (SUVmean), and minimum standardized uptake values (SUVmin) were measured over femoral head and neck. Mann-Whitney U test with Bonferroni correction was used to compare SUVs of ipsilateral and contralateral femurs from femoral neck fracture patients with those of control femurs.RESULTS: As for femoral head viability, SUV(max) and SUVmean were not significantly decreased in non-viable femoral heads compared to those in controls. Only the SUVmin was significantly reduced in non-viable femoral heads (mean ± standard deviation, 0.57 ± 0.38) than in controls (0.95 ± 0.26, p = 0.006) and contralateral femoral heads (1.36 ± 0.59, p = 0.008). The cutoff SUVmin of 0.61 (g/mL) yielded a sensitivity of 77.8% and specificity of 87.1% for detection of non-viable femoral heads (p = 0.006). Contralateral femoral necks of the femoral neck fracture patients showed significantly higher SUVmean and SUVmin (3.17 ± 1.20 and 1.64 ± 0.63) than those of controls (2.32 ± 0.53 and 1.04 ± 0.27; p = 0.021 and p = 0.002, respectively), which seemed to reflect weight bearing effect or metabolic derangement.CONCLUSIONS: The non-viable femoral heads from the femoral neck fracture showed significantly reduced SUVmin. Quantitative bone SPECT/CT holds promise for objective evaluation of femoral head viability.

MET-Amplified Intramucosal Gastric Cancer Widely Metastatic after Complete Endoscopic Submucosal Dissection / Journal of the Korean Cancer Association, 대한암학회지

Intramucosal gastric cancer (IGC) is associated with a very low risk of lymph node metastasis; thus it is the main candidate for minimally invasive surgical procedures, such as endoscopic submucosal dissection (ESD). Herein, we document an extraordinary case of IGC, which showed a very aggressive clinical course. A 66-year-old female underwent ESD for early gastric cancer. Histologically, the tumor consisted mainly of moderately differentiated adenocarcinoma measuring 1.6 cm in diameter, and the tumor was confined to the mucosa. Despite annual esophagogastroduodenoscopic follow-up, the tumor recurred, with wide metastasis to multiple lymph nodes and bones throughout the body after three years. Fluorescence in situ hybridization study demonstrated MET gene amplification as well as low grade polysomy 7 in both original and recurrent tumors. The clinical characteristics of metastatic IGCs and the implication of MET amplification are discussed.

The usefulness and accuracy of sentinel lymph node biopsy using single photon emission computed tomography/computed tomography with 99mTc phytate to detect locoregional lymph node metastases in patients with papillary thyroid carcinoma / 대한외과학회지

PURPOSE: Regional lymph node (LN) metastases are detected in 57-85% of patients with papillary thyroid carcinoma (PTC) and are associated with increased tumor recurrence. However, the management of lymphatic disease in patients with PTC has been ongoing source of debate. We have prospectively assessed the usefulness and accuracy of sentinel LN (SLN) biopsy for the detection of LN metastases in patients with PTC on preoperative imaging using single photon emission computed tomography/computed tomography (SPECT/CT) and 99mTc phytate. METHODS: We prospectively assessed 39 patients with PTC who had risk factors for recurrence or with the necessity of intraoperative LN sampling for suspicious LN metastases on preoperative imaging from August 2010 to March 2011. The patients underwent preoperative lymphoscintigraphy and SPETC/CT and intraoperative SLN biopsy (SLNB). RESULTS: 99mTc lymphoscintigraphy and SPECT/CT localized SLN in 38 patients (97.4%), with the gamma probe identifying 2.15 mean SLNs in the lateral neck of the 39 patients. Skip metastasis was found in one patient, and lateral compartment LN metastasis in 17 (43.5%). The sensitivity, specificity, and accuracy of SLNB for lateral compartment LN metastasis were 88.2%, 100%, and 94.8%, respectively. SLNB was more accurate and useful for lateral than for central compartment LN metastasis. CONCLUSION: SPECT/CT improved SLN detection and anatomical localization compared with lymphoscintigraphy. SLNB in patients with risk factors for recurrence or the necessity of intraoperative LN sampling for suspected LN metastases on preoperative imaging was accurate in detecting LN metastases and may help in deciding whether to perform lateral compartment dissection in patients with PTC.

Inflammatory Pseudotumor in the Mediastinum: Imaging with 18F-Fluorodeoxyglucose PET/CT

Mediastinal inflammatory pseudotumor is a rare benign disease with its capability for local invasion and rapid growth. We present a case of middle-mediastinal inflammatory pseudotumor and report its contrast-enhanced chest computed tomography, 18F-fluorodeoxyglucose positron emission tomography/computed tomography and pathologic findings.

Effectiveness of 124I-PET/CT and 18F-FDG-PET/CT for Localizing Recurrence in Patients with Differentiated Thyroid Carcinoma

Although the prognosis of patients with differentiated thyroid carcinoma (DTC) is generally encouraging, a diagnostic dilemma is posed when an increasing level of serum thyroglobulin (Tg) is noted, without detection of a recurrent tumor using conventional imaging tools such as the iodine-131 whole-body scanning (the [131I] scan) or neck ultrasonography (US). The objective of the present study was to evaluate the diagnostic value of [124I]-PET/CT and [18F]-FDG-PET/CT in terms of accurate detection of both iodine- and non-iodine-avid recurrence, compared with that of conventional imaging such as the [131I] scan or neck ultrasonography (US). Between July 2009 and June 2010, we prospectively studied 19 DTC patients with elevated thyroglobulin levels but who do not show pathological lesions when conventional imaging modalities are used. All involved patients had undergone total thyroidectomy and radioiodine (RI) treatment, and who had been followed-up for a mean of 13 months (range, 6-21 months) after the last RI session. Combined [18F]-FDG-PET/CT and [124I]-PET/CT data were evaluated for detecting recurrent DTC lesions in study patients and compared with those of other radiological and/or cytological investigations. Nine of 19 patients (47.4%) showed pathological [18F]-FDG (5/19, 26.3%) or [124I]-PET (4/19, 21.1%) uptake, and were classed as true-positives. Among such patients, disease management was modified in six (66.7%) and disease was restaged in seven (77.8%). In particular, the use of the described imaging combination optimized planning of surgical resection to deal with locoregional recurrence in 21.1% (4/19) of patients, who were shown to be disease-free during follow-up after surgery. Our results indicate that combination of [18F]-FDG-PET/CT and [124I]-PET/CT affords a valuable diagnostic method that can be used to make therapeutic decisions in patients with DTC who are tumor-free on conventional imaging studies but who have high Tg levels.

18F-FDG PET/CT Finding in a Case of Xanthogranulomatous Pyelonephritis / 핵의학분자영상

Xanthogranulomatous pyelonephritis is an uncommon chronic renal infection, which is usually found on middle-aged women and is rare in infant. Sometimes it forms focal mass like lesion of kidney with pathologically characteristic lipid-laden macrophage. A 1-month female infant was admitted for fever and moaning sound. On work-up of urinary tract infection, abdomen ultrasonography and computed tomography revealed a large mass on the upper portion of right kidney and PET/CT showed homogeneously increased 18F-FDG uptake. The radical nephrectomy of right kidney was performed and histology revealed a focal xanthogranulomatous pyelonephritis. To our knowledge, this is the first report presenting the finding of 18F-FDG PET/CT in the childhood xanthogranulomatous pyelonephritis.

Ipsilateral Cerebral and Contralateral Cerebellar Hyperperfusion in Patients with Unilateral Cerebral Infarction; SPM Analysis / 핵의학분자영상

PURPOSE: Cortical reorganization has an important role in the recovery of stroke. We analyzed the compensatory cerebral and cerebellar perfusion change in patients with unilateral cerebral infarction using statistical parametric mapping (SPM). MATERIALS AND METHODS: Fifty seven (99m)Tc-Ethylene Cystein Diethylester (ECD) cerebral perfusion SPECT images of 57 patients (male/female=38/19, mean age=56+/-17 years) with unilateral cerebral infarction were evaluated retrospectively. Patients were divided into subgroups according to the location (left, right) and the onset (acute, chronic) of infarction. Each subgroup was compared with normal controls (male/female=11/1, mean age=36+/-10 years) in a voxel-by-voxel manner (two sample t-test, p<0.001) using SPM. RESULTS: All 4 subgroups showed hyperperfusion in the ipsilateral cerebral cortex, but not in the contralateral cerebral cortex. Chronic left and right infarction groups revealed hyperperfusion in the ipsilateral primary sensorimotor cortex, meanwhile, acute subgroups did not. Contralateral cerebellar hyperperfusion was also demonstrated in the chronic left infarction group. CONCLUSION: Using (99m)Tc-ECD SPECT, we observed ipsilateral cerebral and contralateral cerebeller hyperperfusion in patients with cerebral infarction. However, whether these findings are related to the recovery of cerebral functions should be further evaluated.

Isolated Splenic Metastasis of Sigmoid Colon Cancer Detected by 18F-FDG PET/CT / 핵의학분자영상

Splenic metastasis from colon carcinoma are rare and usually occur in the presence of disseminated visceral metastasis. The liver is the most common site of metastatic spread from colon cancer. Several hypotheses have attempted to explain the low incidence of splenic metastasis. It should be difficult for colorectal cancer cells to reach the spleen through the portal venous system, in which the blood flow is usually from the spleen to the liver. Reticuloendothelial system or rhythmic contraction of the spleen may squeeze out the tumor in the spleen. The absence of afferent lymphatic to the spleen, phagocytic activity and humoral anticancer substances are considered to be other reason for low incidence of splenic metastasis. We report the case of 18F-FDG PET/CT finding in a 70-year-old woman who develop isolated splenic metastasis of sigmoid colon cancer.

Development of Decision Tree Software and Protein Profiling using Surface Enhanced Laser Desorption/Ionization - Time of Flight - Mass Spectrometry (SELDI-TOF-MS) in Papillary Thyroid Cancer / 핵의학분자영상

PURPOSE: The aim of this study was to develop a bioinformatics software and to test it in serum samples of papillary thyroid cancer using mass spectrometry (SELDI-TOF-MS). MATERIALS AND METHODS: Development of 'Protein analysis' software performing decision tree analysis was done by customizing C4.5. Sixty-one serum samples from 27 papillary thyroid cancer, 17 autoimmune thyroiditis, 17 controls were applied to 2 types of protein chips, CM10 (weak cation exchange) and IMAC3 (metal binding - Cu). Mass spectrometry was performed to reveal the protein expression profiles. Decision trees were generated using 'Protein analysis' software, and automatically detected biomarker candidates. Validation analysis was performed for CM10 chip by random sampling. RESULTS: Decision tree software, which can perform training and validation from profiling data, was developed. For CM10 and IMAC3 chips, 23 of 113 and 8 of 41 protein peaks were significantly different among 3 groups (p<0.05), respectively. Decision tree correctly classified 3 groups with an error rate of 3.3% for CM10 and 2.0% for IMAC3, and 4 and 7 biomarker candidates were detected respectively. In 2 group comparisons, all cancer samples were correctly discriminated from non-cancer samples (error rate = 0%) for CM10 by single node and for IMAC3 by multiple nodes. Validation results from 5 test sets revealed SELDI-TOF-MS and decision tree correctly differentiated cancers from non-cancers (54/55, 98%), while predictability was moderate in 3 group classification (36/55, 65%). CONCLUSION: Our in-house software was able to successfully build decision trees and detect biomarker candidates, therefore it could be useful for biomarker discovery and clinical follow up of papillary thyroid cancer.

18F-FDG PET/CT in POEMS Syndrome / 핵의학분자영상

POEMS syndrome is a rare disorder, also known as Crow-Fukase, PEP or Takatsuki syndrome. The acronym, POEMS, represents polyneuropathy, organomegaly, endocrinopathy, M protein and skin change. However, there are associated features not included in the acronym such as sclerotic bone lesions, Castleman disease, papilledema, thromobocytosis, peripheral edema, ascites, effusion, polycythemia, fatigue and clubbing. In most cases, osseous lesions in POEMS syndrome present as an isolated sclerotic deposit and that reveal as osteosclerotic myeloma. Several cases of 18F-FDG PET in multiple myeloma involvements were reported, but there was no previous literature that reported FDG PET findings in POEMS syndrome. We describe here a 66-year-old patient with POEMS syndrome who underwent 18F-FDG PET/CT image.

Associated Conditions and Clinical Significance of Awake Bruxism

BACKGROUND: Awakebruxism is defined as an oral parafunctional activity that includes clenching and grinding of teeth during wakefulness. Confirming the possible related anatomy and the clinical significance of awake bruxism in Yong-in Hyoja Geriatric Hospital is the aim of this study. METHODS: We analyzed the medical records of 503 patients who were admitted in hospital from April to June 2005. After the recognition of bruxism, the clinical, brain imaging studies and statistical parametric mapping(SPM) of Brain SPECT were done. RESULTS: (1) In each disease group, 5 among 125 Alzheimer's disease(AD) patients(4.0%, 5/125), 3 among 11 frontotemporal dementia(FTD) patients(27.3%; 3/11), 7 among 230 stroke patients(including two patients related with citalopram, 3.0%; 7/230), 1 among 45 Parkinson's disease patients(2.2%; 1/45), and 4 hydrocephalus patient(23.5%; 4/ 17) had bruxism. (2) Even though awake bruxism occurred in early stage after stroke onset, it occurred in late stage after AD and FTD onset. This occurred in far advanced stage of AD, while it occurred in moderately advanced stage of FTD and stroke. (3) SPM analysis in AD and FTD patients with awake bruxism revealed significant hypoperfusion in frontotemporal and other subcortical structures. CONCLUSIONS: This study suggests that awake bruxism is encountered in various diseases in geriatric hospital. It is closely related frontotemporal lobe dysfunction in degenerative dementia like FTD and AD. Therefore it can be regarded as one of marker of frontal or related subcortical neurological sign in degenerative dementia.

Usefulness of Low Dose Oral Contrast Media in 18F-FDG PET/CT / 핵의학분자영상

PURPOSE: The standard protocol using large volume of oral contrast media may cause gastrointestinal discomfort and contrast-related artifacts in PET/CT. The aim of this study was to evaluate the usefulness of low dose oral contrast in 18F-FDG PET/CT. MATERIALS AND METHODS: We retrospectively reviewed the whole-body PET/CT images in a total of 435 patients. About 200 ml of oral contrast agent (barium sulfate) was administered immediately before injection of 18F-FDG. The FDG uptake of intestines was analyzed by visual and semi-quantitative method on transaxial, coronal and saggital planes. RESULTS: Seventy (16%, 113 sites) of 435 images showed high FDG uptake (peak SUV > 4); 50 (74%, 84 sites) with diffuse and 20 (26%, 29 sites) with focal uptake. The most commonly delivered site of oral contrast media was small bowel (n=27, 39%). On PET/CT images, FDG uptake coexisted with oral contrast media in 26 patients (54%, 38 sites) with diffuse pattern and 9 (45%, 9 sites) with focal pattern, and by sites, those were 38 (45%) and 9 (31%), respectively. In small bowel regions, the proportion of coexistence reached as high as 61% (29/47 sites). A visual analysis of available non-attenuation corrected PET images of 27 matched regions revealed no contrast-related artifact. CONCLUSION: We concluded that the application of low dose contrast media could be helpful in the evaluation of abdominal uptake in the FDG PET/CT image.