Evaluation of brain FDG PET images in temporal lobe epilepsy for lateralization of epileptogenic focus using data mining methods

Background/aim: In temporal lobe epilepsy (TLE), brain positron emission tomography (PET) performed with F-18 fluorodeoxyglucose (FDG) is commonly used for lateralization of the epileptogenic temporal lobe. In this study, we aimed to evaluate the success of quantitative analysis of brain FDG PET images using data mining methods in the lateralization of the epileptogenic temporal lobe. Materials and methods: Presurgical interictal brain FDG PET images of 49 adult mesial TLE patients with a minimum of 2 years of postsurgical follow-up and Engel I outcomes were retrospectively analyzed. Asymmetry indices were calculated from PET images from the mesial temporal lobe and its contiguous structures. The J48 and the logistic model tree (LMT) data mining algorithms were used to find classification rules for the lateralization of the epileptogenic temporal lobe. The classification results obtained by these rules were compared with the physicians' visual readings and the findings of single-patient statistical parametric mapping (SPM) analyses in a test set of 18 patients. An additional 5-fold cross-validation was applied to the data to overcome the limitation of a relatively small sample size. Results: In the lateralization of 18 patients in the test set, J48 and LMT methods were successful in 16 (89%) and 17 (94%) patients, respectively. The visual consensus readings were correct in all patients and SPM results were correct in 16 patients. The 5-fold cross- validation method resulted in a mean correct lateralization ratio of 96% (47/49) for the LMT algorithm. This ratio was 88% (43 / 49) for the J48 algorithm. Conclusion: Lateralization of the epileptogenic temporal lobe with data mining methods using regional metabolic asymmetry values obtained from interictal brain FDG PET images in mesial TLE patients is highly accurate. The application of data mining can contribute to the reader in the process of visual evaluation of FDG PET images of the brain.

Comparison of FDG PET/MRI and FDG PET/CT in Pediatric Oncology in Terms of Anatomic Correlation of FDG-positive Lesions.

The aims of our study were to compare F-18 fluorodeoxyglucose (FDG) positron-emission tomography/magnetic resonance imaging (PET/MRI) and PET/computed tomography (CT) in pediatric oncology patients in terms of anatomic correlation of FDG-positive lesions, and also to compare diffusion-weighted imaging (DWI) with PET to assess the correlation between apparent diffusion coefficient (ADC) values and standardized uptake value (SUV). Sequential PET/CT and PET/MRI images and/or whole-body DWI and ADC mapping in 34 pediatric patients were retrospectively analyzed. FDG-positive lesions were visually scored for CT, T1-weighted, T2-weighted, and DWI images separately in terms of anatomic correlation of FDG-avid lesions. Correlation analysis was performed for SUV parameters and ADC values. Among 47 FDG-positive lesions identified concurrently on PET/CT and PET/MRI, 37 were positive on CT and 46 were positive on at least one MRI sequence (P=0.012). Among 32 FDG-positive lesions for which DWI were available, 31 could be clearly depicted on DWI, resulting in significant difference compared with CT alone in the detection of FDG-positive lesions. No correlation was found between ADC and SUV. FDG PET/MRI exhibits better performance than PET/CT in terms of anatomic correlation of FDG-avid lesions. Therefore, PET/MRI may be more advantageous than PET/CT, not only due to reduced ionizing radiation dose but also for a better depiction of FDG-avid lesions in pediatric PET imaging.

Gonadotropin-Releasing Hormone Analog Combined with Depot Medroxyprogesterone Acetate in the Management of Endometrial Hyperplasia A Prospective Randomized Clinical Study.

OBJECTIVE: To compare the effectiveness of combined treatment of depot medroxyprogesterone acetate (MPA) with gonadotropin-releasing hormone (GnRH) analog and depot MPA alone in the management of simple endometrial hyperplasia without atypia among heavy bleeders. STUDY DESIGN: Thirty- four patients with endo- metrial hyperplasia with- out atypia were selected in this prospective randomized study. Group I consisted of 15 patients who were treated with depot MPA combined with GnRH analog. Group 2 consisted of 19 patients who were treated with depot MPA alone. Injections were applied at the beginning of the study and at the end of the 3rd month. Endometrial biopsies were performed at the end of the 6th month. Main outcome measures were endometrial response and reduction of duration and amount of menstrual bleeding. RESULTS: Total and mean duration of menstruation and total number of standardized pads used were signifi- cantly decreased in both groups. These parameters were also significantly lower in group 1 than in group 2 at the end of both the 3rd and 6th months of the study (p<0.01). Endometrial response rates were significant- ly higher in group I than in group 2 (100% vs. 44.4%, respectively, p <0.05). CONCLUSION: Management of endometrial hyper- plasia with GnRH analog in addition to depot MPA provides prompt endometrial response and rapid menstru- al cycle control.

Demonstration of Adaptive Functional Differences Seen in Kidneys Accompanying a Nonfunctioning/Hypofunctioning Partner, using Camera Based Tc 99m MAG3 Clearance Measurement Technique.

OBJECTIVE: The aim of this study was to demonstrate the functional compensation that occurs in kidneys which accompany a partner with total or partial loss of renal functioning mass, using camera-based Tc 99m MAG3 clearance technique. MATERIAL AND METHODS: Eighty five patients (43M, 42F, age: 44.8±12.6, range: 18-77 years) with normal serum creatinine levels and normal (

Comparison of diagnostic performances of three different software packages in detecting coronary artery disease.

PURPOSE: Quantification of myocardial perfusion scintigraphy is frequently performed to assist physicians in detecting coronary artery disease (CAD). Software packages provide automated quantification of perfusion data. We aimed to compare the three commonly used software packages, Emory Cardiac Toolbox (ECT v2 and ECT v3), 4D-MSPECT (4DM v2 and 4DM v4) and Quantitative Perfusion SPECT (QPS v3 and QPS v4). METHODS: We selected 283 patients who had a myocardial perfusion scintigraphy with (201)Tl followed by coronary angiography within 3 months. Summed stress score (SSS), summed difference score (SDS), total stress defect extent (TDE) and regional stress defect extent values were obtained from programs. A ≥70% stenosis in coronary arteries and their major branches was considered positive for CAD. A subgroup of patients was used to form an institutional normal database for QPS and 4DM. Receiver-operating characteristic (ROC) analysis to detect CAD was performed. RESULTS: Mean SSS ± SD (vendor) for ECT v3, QPS v4 and 4DM v4 were 9.2 ± 7.1, 10.1 ± 6.8 and 5.5 ± 6.1, respectively. Area under the curve (AUC) values of SSS ROC analysis were 0.738 ± 0.031 for QPS v3, 0.755 ± 0.030 for QPS v4, 0.758 ± 0.030 for ECT v2, 0.778 ± 0.029 for ECT v3 and 0.771 ± 0.030 for 4DM v4. The AUC values for TDE were 0.755 ± 0.030 for QPS v4, 0.769 ± 0.030 for ECT v3 and 0.775 ± 0.029 for 4DM v4. The differences were not significant for both SSS and TDE. Differences of AUC between regional stress defect extent values of programs and AUC of SSS between institutional and vendor normal databases were not significant. CONCLUSION: The diagnostic performances of programs to detect CAD are similar. However, there are differences in the magnitudes of the quantitative values produced by the programs.

An open-source framework of neural networks for diagnosis of coronary artery disease from myocardial perfusion SPECT.

BACKGROUND: The purpose of this study is to develop and analyze an open-source artificial intelligence program built on artificial neural networks that can participate in and support the decision making of nuclear medicine physicians in detecting coronary artery disease from myocardial perfusion SPECT (MPS). METHODS AND RESULTS: Two hundred and forty-three patients, who had MPS and coronary angiography within three months, were selected to train neural networks. Six nuclear medicine residents, one experienced nuclear medicine physician, and neural networks evaluated images of 65 patients for presence of coronary artery stenosis. Area under the curve (AUC) of receiver operating characteristics analysis for networks and expert was .74 and .84, respectively. The AUC of the other physicians ranged from .67 to .80. There were no significant differences between expert, neural networks, and standard quantitative values, summed stress score and total stress defect extent. CONCLUSIONS: The open-source neural networks developed in this study may provide a framework for further testing, development, and integration of artificial intelligence into nuclear cardiology environment.

[Differences in cerebral blood flow following risperidone treatment in children with autistic disorder]. / Otistik bozuklugu olan cocuklarda risperidon tedavisinin beyin kan akimi ile degerlendirilmesi]

OBJECTIVE: Functional changes in the brains of autistic children due to risperidone treatment and theirs relationship to the symptom clusters are yet unknown. In this autistic disorder case series we aimed to comparatively evaluate the clinical findings before and after risperidone treatment, and regional cerebral blood flow (rCBF) findings with 99mTc-hexamethylpropyleneamine oxime (HMPAO) brain SPECT. METHOD: Eleven autistic patients (age range: 6-7 years; 4 girls, 7 boys) received risperidone therapy (1.5-2.5 mg d(-1)) and were followed-up for 3 months. All the patients underwent neurologic examinations, psychometric examinations, and SPECT imaging, both at the start of risperidone treatment and 3 months after the treatment started. Clinical observations, and the observations of parents and teachers were recorded. These results were compared with cerebral perfusion indices obtained from SPECT data. RESULTS: After 3 months of treatment changes in rCBF were observed in various regions and to varying degrees. We observed relationships between clinical symptoms and pre-therapy rCBF findings, and between clinical improvement and rCBF changes. CONCLUSION: Findings in the present case series are the first to demonstrate a relationship between clinical improvement and regional perfusion patterns after risperidone treatment. We think that these findings may contribute to the understanding of the neurofunctional mechanisms and hypothetical models of autism.

Gonadotropin-releasing hormone analog combined with a low-dose oral contraceptive to treat heavy menstrual bleeding.

OBJECTIVE: To compare the effects of low-dose oral contraceptives used alone and in combination with a gonadotropin-releasing hormone (GnRH) analog to treat heavy menstrual bleeding. METHODS: Fifty-eight patients with heavy menstrual bleeding were prospectively randomized into two treatment groups to receive either a low-dose oral contraceptive alone (group 1), or combined with a GnRH analog (group 2) for 6 months. The patients' hormonal profiles, and hemoglobin and hematocrit levels were measured at the beginning and at the end of the treatment period. RESULTS: Hemoglobin and hematocrit levels significantly improved in both groups after 6 months of treatment (P<0.05 and P<0.01, respectively). Even in the first month of the study, the number of pads used and the duration of menstruation were significantly decreased in both groups and markedly lower in group 2 (P<0.01). CONCLUSION: The addition of a GnRH analog to low-dose oral contraceptive treatment for heavy menstrual bleeding resulted in better control of vaginal bleeding, even in the first month of therapy.

Could the simplified (14)C urea breath test be a new standard in noninvasive diagnosis of Helicobacter pylori infection?

OBJECTIVE: The carbon-14 ((14)C) urea breath test (UBT) is a reliable and noninvasive technique for the diagnosis of Helicobacter pylori (HP) infection. The diagnostic performance of a new practical and low dose (14)C UBT system (Heliprobe, Stockholm, Sweden) was compared with those of other diagnostic tests, namely, rapid urease test (RUT), histopathology, and DNA detection using polymerase chain reaction (PCR). METHODS: Eighty-nine patients (mean age = 45 +/- 13, 30 men) with dyspeptic complaints who underwent an endoscopic procedure were studied. Biopsy specimens acquired during the procedure were subjected to RUT, histopathological examination using hematoxylin and eosin (HP-HE) and PCR. All patients underwent UBT using the Heliprobe system on a different day. The gold standard for HP positivity was defined as any two of the three tests being positive, excluding UBT, and the sensitivity and specificity of any single test alone were determined using this gold standard. Whenever only one test was positive, it was considered to be a false-positive one. RESULTS: With the gold standard used in this study, 59 (66%) patients were diagnosed HP positive. The Heliprobe method detected HP infection with 96.6% sensitivity and 100% specificity and had the best diagnostic performance when compared with all the other methods. The sensitivity and specificity of the other methods for the detection of HP positivity were 89.8% and 100% for RUT, 93.2% and 63.3% for PCR, and 93.2% and 76.6% for HP-HE, respectively. Areas under the receiver-operating characteristic were 0.977 for UBT, 0.947 for RUT, 0.84 for HP-HE, and 0.775 for PCR. CONCLUSIONS: Using a combination of invasive diagnostic tests as the gold standard, Heliprobe UBT was found to be highly sensitive and specific for the diagnosis of HP infection in patients with dyspeptic complaints.

Disseminated extranodal NK/T-cell lymphoma, nasal type, with multiple subcutaneous nodules: utility of 18F-FDG PET in staging.

A 49-year-old man presented with a left nasal cavity mass, biopsy of which revealed extranodal NK/T cell lymphoma. A PET-CT scan showed increased F-18 FDG uptake in the nasal mass, anterior mediastinal lymph nodes, and multiple subcutaneous nodular deposits in the chest wall, gluteal region, and right femoral areas. The patient achieved complete remission with salvage l-asparaginase therapy after failing first-line standard anthracycline-based chemotherapy. PET-CT was very useful in detecting subcutaneous nodules consistent with widespread dissemination. There is limited literature data on the use of the PET scan in the diagnosis and staging of extranodal nasal NK/T-cell lymphomas. Our case highlights the important role of F-18 FDG PET in the staging of these patients.

Functional brain imaging in Sydenham's chorea and streptococcal tic disorders.

Group A streptococcal infections cause a wide range of neuropsychiatric disorders, such as Sydenham's chorea, tics, obsessive-compulsive disorders, and pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS). Structural (computed tomography and magnetic resonance imaging) and functional (positron emission tomography, single-photon emission computed tomography) imaging studies in patients with Sydenham's chorea have suggested reversible striatal abnormalities. The objective of this study was to investigate the cerebral perfusion patterns of the subcortical structures by using hexamethylpropylenamine oxime single-photon emission computed tomography (HMPAO-SPECT) in seven cases of Sydenham's chorea and two cases of streptococcal tic disorder. HMPAO-SPECT studies revealed a hyperperfusion pattern in two and a hypoperfusion pattern in five of the chorea patients and in two patients with tic disorder. The results are discussed in relation to the duration and severity of the symptoms and the response to therapy. Functional imaging findings can be variable in Sydenham's chorea, and hyperperfusion of the striatum and thalamus could be an indicator of the response to therapy and the severity of symptoms. However, the number of cases so far investigated by either SPECT or positron emission tomography is still too limited to draw any firm conclusions.

Tc-99m-HMPAO SPECT in the diagnosis of brain death in children.

BACKGROUND: The diagnosis of brain death is based on both clinical and laboratory findings. However, diagnosis of brain death is still contentious and reliable tests are required. Early recognition and declaration of the diagnosis is the main goal, which is important for discontinuation of life support and organ donation for transplantation. In order to achieve this goal, competent diagnostic procedures should be performed. In this paper the authors review the diagnosis of brain death in eight children from different age groups, with an emphasis on factors concerning the reliability, use and appropriate application time of Tc-99m-HMPAO single photon emission computed tomography (SPECT) in early diagnosis in infants and newborns. METHODS: Eight patients who fulfilled the clinical criteria of brain death underwent Tc-99m HMPAO SPECT and electroencephalogram (EEG) monitoring. RESULTS: All patients had electrocerebral silence on EEG recordings. Six patients showed lack of perfusion in cerebrum in their first SPECT, however, newborns needed a second image for a confirmed diagnosis. CONCLUSION: In infants, SPECT has a high reliability for confirmed diagnosis of brain death; however, in newborns the application time is important for an accurate diagnosis.

Bilateral Swyer-James (Macleod's) syndrome.

Swyer James syndrome (SJS) is a rare disorder. It is generally discovered on a chest radiograph as increased translucency involving one hemithorax with diminished vascular markings. We present a 5-year-old girl admitted for the treatment of recurrent bronchiolitis. She was diagnosed as having Swyer James syndrome from the results of CT scan and ventilation perfusion scintigraphy, which revealed unsuspected bilateral involvement. This condition should be considered as a differential diagnosis in a patient with Swyer James (Macleod's) syndrome without an obvious etiology.