Potential Clinical Applications of ¹⁸F-Fluorodeoxyglucose Positron Emission Tomography/Magnetic Resonance Mammography in Breast Cancer / 대한핵의학회잡지

The whole-body positron emission tomography (PET)/magnetic resonance (MR) scan is a cutting edge technology providing comprehensive structural information from MR imaging and functional features from PET in a single session. Recent research findings and clinical experience have shown that ¹⁸F-fluorodeoxyglucose (FDG) whole-body PET/MRimaging has a diagnostic performance comparable with or superior to that of PET/CT in the field of oncology, including for breast cancer. In particular, FDG PET/MR mammography in the prone position with the breast hanging in a pendant manner can provide more comprehensive information about the metabolism, anatomy, and functional features of a breast lesion than a whole-body PET/MR scan. This article reports on current state-of-the-art PET/MR mammography in patients with breast cancer and the prospects for potential application in the future.

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.

Kikuchi-Fujimoto disease mimicking malignant lymphoma with 2-18Ffluoro-2-deoxy-D-glucose PET/CT in children / 소아과

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.

Diagnostic Accuracy of 64-Slice MDCT Coronary Angiography for the Assessment of Coronary Artery Disease in Korean Patients with Type 2 Diabetes

BACKGROUND: A 64-slice multidetector computed tomography (MDCT) is well known to be a useful noninvasive form of angiography for the general population, but not for certain patients with diabetes. The aim of this study was to investigate the diagnostic accuracy and usefulness of 64-slice MDCT coronary angiography for detecting coronary artery disease in Korean patients with type 2 diabetes mellitus (T2DM). METHODS: A total of 240 patients were included, 74 of whom had type 2 diabetes (M:F=40:33; 41.8+/-9.5 years). We compared significant coronary stenosis (>50% luminal narrowing) in MDCT with invasive coronary angiography (ICA) by segment, artery, and patient. We also evaluated the influence of obesity and coronary calcium score on MDCT accuracy. RESULTS: Of the 4,064 coronary segments studied, 4,062 segments (T2DM=1,109) were assessed quantitatively by both MDCT and ICA, and 706 segments (T2DM=226) were detected as a significant lesion by ICA in all patients. Sensitivity, specificity, as well as positive and negative predictive values for the presence of significant stenosis in T2DM were: by segment, 89.4%, 96.4%, 85.8%, and 97.4%, respectively; by artery (n=222), 95.1%, 92.9%, 94.4%, and 93.8%, respectively; by patients (n=74), 98.4%, 100.0%, 98.4%, and 90.0%, respectively. Regardless of presence of diabetes, there was no significant difference in diagnostic accuracy. Obesity (> or =25 kg/m2) and coronary calcium score did not also affect the diagnostic accuracy of MDCT. CONCLUSION: The 64-slice MDCT coronary angiography was found to have similar diagnostic accuracy with ICA, regardless of diabetes. These results suggest MDCT may be helpful to reduce unnecessary invasive studies for patients with diabetes.

FDG Uptake Pattern of a Prosthetic Graft without Infection on a PET/CT Scan

PURPOSE: A prosthetic graft infection is a rare but often disastrous complication during vascular surgery. Diagnosis of a prosthetic graft infection is not always easy, particularly with a low virulent bacterial infection or in a deeply placed graft in the retroperitoneal space. Recently, fludeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) has been proposed as a diagnostic modality for prosthetic graft infection. However, some reports have indicated that high FDG uptake occur in grafts without infections. This study analyzed FDG uptake patterns in prosthetic grafts of asymptomatic patients. METHODS: We reviewed 14,545 patients who had received PET/CT in a tertiary hospital between July 2007 and March 2010. Of them, 11 patients who had undergone previous bypass surgery with a prosthetic graft were identified. Four underwent an aortic bypass and the others received lower extremity bypass grafting. PET/CT images and patient clinical data were reviewed retrospectively. The maximum standardized uptake value (SUVmax, A) in the graft, the mean SUV (SUVmean, B) of the blood-pool, and the target-to-background ratio (T/B, A/B) were calculated. RESULTS: The mean duration between bypass grafting and the PET/CT scan was 21 months (range, 1~80 months). No clinical evidence of graft infection was observed in any of the patients. PET/CT revealed an uneven, diffuse FDG uptake pattern on the grafts, and the mean T/B was 2.0 (range, 0.9~4.6). T/B was greater than 2.0 in six patients (55%). CONCLUSION: A prosthetic graft without an infection can result in increased FDG uptake during PET/CT. A further prospective study is necessary to evaluate the usefulness of FDG PET/CT for diagnosing a prosthetic graft infection.

Myocardial Perfusion PET / 핵의학분자영상

Positron emission tomogrpahy (PET) represents the most advanced scintigraphic imaging technology. With the increase in availability of PET, the clinical use of PET has grown in medical fields. This can be employed for cardiovascular research as well as for clinical applications in patients with various cardiovascular disease. PET allows non-invasive functional assessment of myocardial perfusion, substrate metabolism and cardiac innervation and receptors as well as gene expression in vivo. PET is regarded as the gold standard for the detection of myocardial viability, and it is the only method available for the quantitative assessment of myocardial blood flow. This review focuses on the clinical applications of myocardial perfusion PET in coronary artery disease.

F-18 FDG PET/CT Findings of Subcutaneous Panniculitis - Like T- Cell Lymphoma : A Case Report / 핵의학분자영상

F-18 FDG PET is a metabolic imaging modality that is efficacious in staging and assessment of treatment response for variety of lymphomas. We report usefulness of F-18 FDG PET/CT in evaluating severity of the disease and response to therapy in a patient with subcutaneous panniculitis- like T-cell lymphoma (SPTCL). Here we describe a case of SPTCL in 24-year-old man who had wide spread firm and tender nodular lesions with increased F-18 FDG uptake. After chemotherapy follow up F-18 FDG PET/CT image shows disseminated malignancy and then the patient died with hemophagocytic syndrome. This report suggests that F-18 FDG PET/CT may be useful in determining disease activity at the time of initial diagnosis, after treatment, and evaluating a suspected outcome of SPTCL.

Added Value of 3D Cardiac SPECT/CTA Fusion Imaging in Patients with Reversible Perfusion Defect on Myocardial Perfusion SPECT / 핵의학분자영상

PURPOSE: Integration of the functional information of myocardial perfusion SPECT (MPS) and the morphoanatomical information of coronary CT angiography (CTA) may provide useful additional diagnostic information of the spatial relationship between perfusion defects and coronary stenosis. We studied to know the added value of three dimensional cardiac SPECT/CTA fusion imaging (fusion image) by comparing between fusion image and MPS. MATERIALS AND METHODS: Forty-eight patients (M:F=26:22, Age: 63.3+/-10.4 years) with a reversible perfusion defect on MPS (adenosine stress/rest SPECT with Tc-99m sestamibi or tetrofosmin) and CTA were included. Fusion images were molded and compared with the findings from the MPS. Invasive coronary angiography served as a reference standard for fusion image and MPS. RESULTS: Total 144 coronary arteries in 48 patients were analyzed; Fusion image yielded the sensitivity, specificity, negative and positive predictive value for the detection of hemodynamically significant stenosis per coronary artery 82.5%, 79.3%, 76.7% and 84.6%, respectively. Respective values for the MPS were 68.8%, 70.7%, 62.1% and 76.4%. And fusion image also could detect more multi-vessel disease. CONCLUSION: Fused three dimensional volume-rendered SPECT/CTA imaging provides intuitive convincing information about hemodynamic relevant lesion and could improved diagnostic accuracy.

Clinical Application of Cardiac Hybrid Imaging in Coronary Artery Disease / 영남의대학술지

Constant technological developments in coronary artery disease have contributed to the assessment of both the presence of coronary stenosis and its hemodynamic consequences. Hence, noninvasive imaging helps guide therapeutic decisions by providing complementary information on coronary morphology and on myocardial perfusion and metabolism. This can be done using single photon emission computed tomography(SPECT) or positron emission tomography(PET) and multidetector CT(MDCT). Advances in image-processing software and the advent of SPECT/CT and PET/CT have paved the way for the combination of image datasets from different modalities, giving rise to hybrid imaging. Three dimensional cardiac hybrid imaging helped to confirm hemodynamic significance in many lesions, add new lesions such as left main coronay artery disease, exclude equivocal defects, correct the corresponding arteries to their allocated defects and identify culprit segment. Cardiac hybrid imaging avoids the mental integration of functional and morphologic images and facilitates a comprehensive interpretation of coronary lesions and their pathophysiologic adequacy by three dimensional display of fused images, and allows the best evaluation of myocardial territories and the coronary-artery branches that serve each territory. This integration of functional and morphological information were feasible to intuitively convincing and might facilitate developmnt of a comprehensive non-invasive assessment of coronary artery disease.

The Combination of Fasting Plasma Glucose and Glycosylated Hemoglobin as a Predictor for Type 2 Diabetes in Korean Adults / 당뇨병

BACKGROUND: The oral glucose tolerance test (OGTT) for detection of diabetes is difficult to perform in clinical settings. The aim of this study is to evaluate the performance of a more practical detection test, combined fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1c), as a predictor of diabetes mellitus (DM) in a Korean sample. METHODS: We examined 2,045 (M = 1,276, mean age = 47.8 +/- 9.0 yrs) medical check-up program participants between January 2002 to December 2003. FPG, HbA1c and a number of other biochemical tests were performed at baseline and four after years after initial screening. Patients who originally presented with diabetes were excluded. The characteristics of newly-diagnosed DM patients and non-diabetic patients were compared. RESULTS: The incidence of newly diagnosed diabetes was 1.6% (32/2,045) after four years of follow up. The subjects in the DM group were older, had higher levels of SBP, DBP, FPG, HbA1c, triglyceride, HDL cholesterol, GGT and LDH (P < 0.05). In multivariate logistic regression analysis, FPG (odds ratio [OR] 1.124) and HbA1c (OR 4.794) were significantly correlated with onset of diabetes (P < 0.05). The interaction parameter between FPG and HbA1c was more than 1.0, indicating that the two effects are synergistic. The predictive cut-off values of HbA1c and FPG were 5.35% (area under curve [AUC] = 0.944) and 102.5 mg/dL (AUC = 0.930), respectively. CONCLUSION: The combination of HbA1c above 5.35% and FPG above 102.5 mg/dL predicted the onset of diabetes in a Korean sample. These results suggest that the combination of FPG and HbA1c may be useful for predicting progression to type 2 diabetes in east Asians.

Relationship Between Serum Bilirubin Levels and Coronary Atherosclerosis in Patients with Type 2 Diabetes / 당뇨병

BACKGROUND: Lipid oxidation and formation of oxygen radicals have been identified to be the important factors of atherogenesis. Because bilirubin, a potent physiological antioxidant inhibits lipid oxidation, it is suggested that low serum concentrations of bilirubin is associated with atherosclerosis. The aim of this study was to evaluate the relationship between bilirubin levels and coronary atherosclerosis. METHODS: The coronary calcium score (CCS) of 172 subjects (male 63, mean age 60.5 +/- 1.0) with type 2 diabetes were evaluated in Yeungnam University Hospital between January 2005 and February 2007. The subjects were divided into two groups with CCS 10 as the cut off. RESULTS: Higher CCS was significantly associated with lower bilirubin (P < 0.05), but after adjusted with age, no longer correlation were seen (P = 0.121). To determine the relationship between subclinical coronary atherosclerosis and bilirubin, the subjects with previous history of cardiovascular disease were excluded. In 138 subjects (male 54, mean age 58.4 +/- 1.1), higher CCS was significantly associated with lower levels of bilirubin. After adjusted with age, duration of diabetes, and history of hypertension, CCS was also inversely related with bilirubin (P < 0.05). CONCLUSION: These results suggest that lower levels of bilirubin might be considered as a risk factor of coronary artery disease, especially in type 2 diabetics without cardiovascular disease.

Giant aneurysm and fistula fed by multiple arteries and draining into the pulmonary artery: detection by 64-multidetector coronary CT angiography / 대한내과학회지

No abstract available.

Radius Intermedius Stenosis Induced Myocardial Perfusion Defect: Provened by the Fusion Images of Myocardial Perfusion SPECT and 64 Channel CTA / 핵의학분자영상

A 71-year-old woman was assigned to our department for Tc-99m myocardial perfusion SPECT(MPS) and coronary CT angiography. She admitted for substernal pain, via the ER, 2 days ago. The heart was scanned after intravenous injection of 925 MBq of (99m)Tc-sestamibi adenosine-induced stress SPECT using dual head gamma camera (Hawkeye, GE healthcare. USA). The MPS shows decreased tracer uptake in the apical & mid area of anterior & lateral wall and mid & basal inferior wall. Coronary CT angiograph was obtained using Discovery VCT (GE healthcare). 3D angiography portrayed significant stenosis of ramus intermedius(RI) and posterolateral branch of right coronary artery(PLB) with fibrocalcified plaque. Two images were fused using Cardiac IQ fusion softwear package (Advantage workstation 4.4, GE healthcare) The fusion images explain the perfusion defect of anterior, lateral and inferior wall is due to stenosis of the RI and PLB. And 3 days later, coronary angiography was done and revealed the marked stenosis of RI and PLB. Then balloon angioplasty and stent was instituted in RI. Cardiac SPECT/CT fusion imaging provides additional information about hemodynamic relevance and facilitates lesion interpretation by allowing exact allocation of perfusion defects to its subtending coronary artery.1,2)

Non-specific Inflammatory Disease Showed Abnormal FDG Uptake in Lower Extremities / 핵의학분자영상

Including malignancy, various disease can show abnormal uptake in bone marrow.1,2) We report a case of non-specific inflammatory FDG uptake in bone marrow mimicking malignancy. A 35-year old woman with fever of unknown origin (FUO) underwent 18F-FDG PET/CT to find out fever focus and unknown malignancy. 18F-FDG was injected and imaged 1hr after injection with Discovery ST (GE, USA). 18F-FDG PET/CT whole body image showed abnormal uptake in lower extremities (Fig. 1). MRI and biopsy was also done in the sites of abnormal uptake. PET and MRI suspect malignancy (Fig. 2, 3), but biopsy result was non-specific inflammatory process (Fig. 4). The patient was improved her clinical condition after antibiotics therapy.

Three Dimensional Volume Rendering Fusion Images Using F-18 FDG PET/CT in Evaluation of Cholangiocellular Carcinoma / 핵의학분자영상

A 69-year old male with cholangiocellular carcinoma (CCC) was assigned to our department for whole body PET/CT scan. 18F- FDG PET/CT images showed an intense hypermetabolic lobulating mass(SUV(max)= 8.7 / size : 11.4 mm) in the right hepatic lobe with multiple metastatic lung nodules. We made three dimensional volume rendering fusion images by using advantage workstation 4.3 (GE health care) which provide quick anatomic overview and improve the planning process significantly.1)

Comparison of Clinical Usefulness between N-13 Ammonia PET/CT and Tc-99m Sestamibi SPECT in Coronary Artery Disease / 핵의학분자영상

PURPOSE: N-13 ammonia uptake and retention in the myocardium is related to perfusion and metabolism. There are several potential advantages of N-13 ammonia positron emission tomography (PET) to detect myocardial ischemia, such as higher spatial resolution, greater counting efficiencies, and robust attenuation correction. But there are few reports comparing Tc-99m myocardial perfusion single photon emission tomography (MPS) and N-13 ammonia PET. We thus compared adenosine stress N-13 ammonia PET/CT and Tc-99m sestamibi MPS in patients with suspected coronary artery stenosis. MATERIALS AND METHODS: Seventeen patients (male 13 : 63+/-11 years old) underwent adenosine stress N-13 ammonia PET/CT (Discovery ST, GE), Tc-99m sestamibi MPS (dual head gamma camera, Hawkeye, GE) and coronary angiography within 1 week. N-13 ammonia PET/CT and Tc-99m sestamibi MPS images were assessed with a 20-segment model by visual interpretation and quantitative analysis using automatic quantitative software (Myovation, GE). RESULTS: Both sensitivities and specificities of detecting an individual coronary artery stenosis were higher for N-13 ammonia PET/CT than Tc-99m sestamibi MPS (PET/CT: 91%/ 89% vs MPS: 65%/ 82%). N-13 ammonia PET/CT showed reversibility in 52% of segments that were considered non-reversibile by Tc-99m sestamibi MPS. In the 110 myocardial segments supplied by the stenotic coronary artery, N-13 ammonia PET/CT showed higher count densities than Tc-99m MPS on rest study (p<0.01), and the difference of count density between the stress and the rest studies was also larger on N-13 ammonia PET/CT. CONCLUSION: Adenosine stress N-13 ammonia PET/CT had higher diagnostic sensitivity and specificity, more reversibility of perfusion defects and greater stress/rest uptake differences than Tc-99m sestamibi MPS. Accordingly, N-13 ammonia PET/CT might offer better assessment of myocardial ischemia and viability.

The Role of Dynamic CT for the Differential Diagnosis of Solitary Pulmonary Nodule / 영남의대학술지

BACKGROUND: Malignant pulmonary nodules account for 30 to 40 percent of all solitary pulmonary nodules (SPNs). Therefore, characterization of SPNs is very important for treatment. Recently, dynamic CT has been widely used for tissue characterization and formation of differential diagnoses. The purpose of this study was to evaluate the ability of dynamic CT to formulate the differential diagnosis of SPNs. MATERIALS AND METHODS: Nineteen patients with SPNs underwent dynamic CT (unenhanced scans, followed by a series of images at 20, 40, 60, 80, 100, 120, 140, 160, and 180 sec after intravenous injection of contrast medium). Diagnosis of SPN was performed based on pathologic findings in needle biopsy samples. Peak enhancement, net enhancement, slope of enhancement, and maximum relative enhancement ratio of the SPN were measured on dynamic CT, and Levene's test was performed to assess benignancy and malignancy. RESULTS: Twelve SPNs were confirmed to have malignant pathology. There were no significant differences between benign and malignant nodules with respect to peak enhancement (p=0.787), net enhancement (p=0.135), or slope of enhancement (p=0.698). The maximal enhancement ratio was increased in malignancy compared to benignancy, but the difference was not statistically significant (p=0.094). CONCLUSION: In our study, the hemodynamic characteristics of dynamic CT were not significantly different between benign and malignant nodules. Therefore, long-term studies of larger patient samples are required to confirm our findings.

Hypertrophic Cardiomyopathy Complicated by Left Ventricular Apical Necrosis and Aneurysm in a Young Man: FDG-PET Findings

A 29-year old male was transferred to our hospital with an abnormal chest X-ray finding diagnosed as hypertrophic cardiomyopathy with apical necrosis and aneurysm formation. Four years after the initial hospitalization, we confirmed the aneurysm and necrosis using both integrated positron emission tomography (PET) and computed tomography (CT) scanning. The F-18 2-fluoro-2-deoxy-D-glucose (FDG) PET/CT enabled precise localization of the aneurysm, which was found to be composed of semi-lunar calcification of non-metabolic myocardium. A contrast-enhanced CT angiography showed an hour-glass appearance of the left ventricular cavity. The integrated PET/CT fusion scanner is a novel multimodality technology that allows for a comprehensive analysis of the anatomical and functional status of complex heart disease. Based on these findings, long standing mechanical and physiologic abnormalities may have led to chronic ischemia in the hypertrophied myocardium, induced necrosis and calcification at the cardiac apex.

The Differentiation of Malignant and Benign Musculoskeletal Tumors by F-18 FDG PET/CT Studies: Determination of maxSUV by Analysis of ROC Curve / 핵의학분자영상

PURPOSE: We evaluated the standard uptake value (SUV) of F-18 FDG at PET/CT for differentiation of benign from malignant tumor in primary musculoskeletal tumors. MATERIALS AND METHODS: Forty-six tumors (11 benign and 12 malignant soft tissue tumors, 9 benign and 14 malignant bone tumors) were examined with F-18 FDG PET/CT (Discovery ST, GE) prior to tissue diagnosis. The maxSUV(maximum value of SUV) were calculated and compared between benign and malignant lesions. The lesion analysis was based on the transverse whole body image. The maxSUV with cutoff of 4.1 was used in distinguishing benign from malignant soft tissue tumor and 3.05 was used in bone tumor by ROC curve. RESULTS: There was a statistically significant difference in maxSUV between benign (n=11; maxSUV 3.4+/-3.2) and malignant (n=12; maxSUV 14.8+/-12.2) lesions in soft tissue tumor (p=0.001). Between benign bone tumor (n=9; maxSUV 5.4+/-4.0) and malignant bone tumor (n=14; maxSUV 7.3+/-3.2), there was not a significant difference in maxSUV. The sensitivity and specificity for differentiating malignant from benign soft tissue tumor was 83% and 91%, respectively. There were four false positive malignant bone tumor cases to include fibrous dysplasia, Langerhans-cell histiocytosis (n=2) and osteoid osteoma. Also, one false positive case of malignant soft tissue tumor was nodular fasciitis. CONCLUSION: The maxSUV was useful for differentiation of benign from malignant lesion in primary soft tissue tumors. In bone tumor, the low maxSUV correlated well with benign lesions but high maxSUV did not always mean malignancy.

Scintigraphic Evaluation of Inhalation Injury in Fire Victims / 핵의학분자영상

PURPOSE: Conventional chest X-ray and pulmonary function test cannot sensitively detect inhalation injury. Bronchoscopy is known to be the gold standard but it is invasive method. We evaluated whether lung inhalation/perfusion scans can sensitively detect inhalation injury of fire victims. MATERIALS AND METHODS: Nineteen patients (male 9, female 10, mean age 31.6 yr) of fire victims were enrolled in this study. Inhalation lung scan was performed 2 days later after inhalation injury with 99mTc-technegas. Perfusion lung scan was performed 4 days later with 99mTc-MAA (macroaggregated albumin). Follow up lung scans were performed 16 and 18 days later for each. Chest X-ray was performed in all patients and bronchoscopy was performed in 17 of 19 patients at the same period. Pulmonary function test was performed in 9 patients. RESULTS: Four of 19 patients showed inhalation and perfusion defects and one showed inhalation defect but, normal perfusion scan findings. These five patients with abnormal scan findings showed abnormal bronchoscopic findings and severe respiratory symptoms. On chest X-ray, 2 of them had pulmonary tuberculosis and one of them showed pulmonary congestion. FEV1/FVC was abnormal in 3 patients. On the follow up scan, all patients with abnormal initial scan findings showed improved findings and they had improved clinical state. CONCLUSION: Inhalation/perfusion lung scans can detect inhalation burn injury noninvasively in early stage and may be useful in therapeutic decision making and follow up of patients.