Neşe İlgin Karabacak

Functional Brain Imaging in Sydenham's Chorea and Streptococcal Tic Disorders

Group A streptococcal infections cause a wide range of neuropsychiatric disorders, such as Sydenhams 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 Sydenhams 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 Sydenhams 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 Sydenhams 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. (J Child Neurol 2004;19:387-390).

Rotational vestibular epilepsy from the temporo-parieto-occipital junction

Humans likely have multiple cortical areas for processing vestibular information rather than a primary vestibular cortex.1 The parietal, temporal, and frontal lobes contain areas that receive vestibular input, with the temporo-perisylvian vestibular cortex having a dominant role.2 Cortical stimulation studies and naturally occurring lesions such as strokes have helped map the human vestibular cortex. Alternatively, partial seizures can serve as a natural form of cortical stimulation for mapping human cortical function. Ictal EEG recordings demonstrate that the posterior portion of the middle frontal gyrus receives rotational vestibular input and can serve as the focus for epileptic rotational vertigo.3 Although previous studies implicate the parieto-temporal area as a focus for vestibular epilepsy,4 direct clinical evidence is lacking. We report a boy with partial epilepsy characterized by rotational vertigo and ipsilateral head and eye deviation with jerking eye movements triggered visually following a moving object. An otherwise healthy, developmentally normal 8-year-old boy was evaluated for a 3-year history of episodes of dizziness and eye jerking. These episodes lasted <1 …

TL-201 scintigraphy, mammography and ultrasonography in the evaluation of palpable and nonpalpable breast lesions: a correlative study☆

PURPOSE To determine the feasibility of Tl-201 as a tumor localizing agent in palpable and nonpalpable breast lesions, in comparison with mammography and ultrasonography (US), and to evaluate the contribution of these modalities to each other in obviating biopsy. MATERIALS AND METHODS Seventy-two palpable and nonpalpable breast lesions were prospectively classified as benign, indeterminate, or malignant according to the sonographic and mammographic criteria and were further analyzed with Tl-201 scanning. These classifications were compared with biopsy results. The sensitivity, specificity, accuracy, false positive and false negative rates (FPR, FNR), negative and positive predictive values (npv, ppv) were calculated for each individual modality and combination of modalities to evaluate the contribution of these three techniques to each other. RESULTS Of 72 lesions 52 were histologically malignant and 20 were benign. Overall, mammography was the most sensitive (92%) and Tl-201 was the most specific (75%) of the three modalities. Mammography + Tl combination was the most specific (90%) and accurate (97%) of dual combinations. In mammographically or sonographically indeterminate cases, Tl-201 was much more specific (75% versus 37% for mammography and US) and more accurate (82% versus 36% for mammography and 54% for US) than the other two modalities, and mammography + Tl combination was significantly superior to other dual combinations (87% specific and 91% accurate). Use of Tl-201 scanning as an adjunct to mammography + US combination increased the specificity, ppv, and accuracy rates overall, particularly in mammographically or sonographically indeterminate cases. CONCLUSIONS In mammographically and sonographically indeterminate breast lesions thallium scanning may be offered as a third step of investigation to obviate biopsy.

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

ObjectiveThe carbon-14 (14C) 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 14C 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).MethodsEighty-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.ResultsWith 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.ConclusionsUsing 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.

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

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.

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

BackgroundThe 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 ResultsTwo 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.ConclusionsThe 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.

Assessment of brain perfusion by 99mTc-HMPAO SPECT in akinetic mutism due to high-dose intravenous methotrexate therapy

Abstract Chemotherapy of the central nervous system may cause neurotoxicity in children with acute lymphocytic leukemia. We evaluated regional blood flow in a 6-year-old child presenting with akinetic mutism, using 99mTc-HMPAO single photon emission tomography (SPECT) following high-dose intravenous methotrexate therapy. While findings in X-ray computerized tomography were decreased density in bilateral basal ganglia and thalamic nuclei with diffusely decreased attenuation of the periventricular white matter, a global, frontal dominant profoundly abnormal perfusion pattern involving both gray and white matter was observed in the SPECT study. Treatment of the central nervous system with high dose intravenous chemotherapy may cause profound abnormalities in white and gray matter blood flow and early assessment of the neurotoxicity may be identified by 99mTc-HMPAO SPECT in the pediatric age group.

Autoimmune Limbic Encephalitis Associated with Type 1 Diabetes Mellitus

A 16-year-old boy was admitted to our emergency department with confusion and headache. Electroencephalography revealed temporal slowing, cerebral magnetic resonance imaging demonstrated hyperintense signal of the right mesiotemporal lobe, and positron emission tomography demonstrated increased activity in the right temporal lobe. Blood glutamic acid decarboxylase antibody (anti-GAD) level was 2114 IU/mL (0–10) and the cerebrospinal fluid anti-GAD level was 4.07 nmol/L (<0.02). These findings led to a consideration of autoimmune LE as a possible diagnosis. Pulse methylprednisolone was administered over five days. After steroid treatment, symptoms improved, but hyperglycemia occurred on the third day of treatment. Glycemia level reached 502 mg/dL. Concurrent insulin level was 42 μIU/mL. Hyperglycemia improved after cessation of steroid treatment. Glycated hemoglobin was 5.6%. The possibility of a steroid-induced hyperglycemia was considered. Six months later, the patient was readmitted with dyspnea and abdominal pain. The family reported occurrence of polyuria and polydipsia during the previous two months. Blood anti-GAD level was >2000 IU/mL. The patient was diagnosed to have T1D. With treatment, the ketoacidosis improved in 10 h. After being educated for diabetes, the patient was discharged. Two months later, he presented with a headache and confusion again. Intravenous immunoglobulin (IVIG) 1 g/kg/d for two days every month was administered. Neurological symptoms improved and the daily insulin dose was decreased.

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 (<Grade 1) Tc 99m MAG3 renogram curves were enrolled for this retrospective study. Patients were grouped as having; group 1: solitary normal kidney (unilateral atrophied/agenetic) (n=23), group 2: normal kidney with contralateral hypoplasic/hypofunctioning kidney (split renal function<30%), (n=24), group 3: bilateral normal kidneys (n=38). The measured camera based Tc 99m MAG3 clearances of normal kidneys in each group were compared. Results: Total Tc 99m MAG3 clearances (mL/min/1.73m2) were significantly lower in group 1 and group 2 compared to group 3 (281.5±46, 260.5±61.7 and 316.1±84, respectively). Highest isolated Tc 99m MAG3 clearances among normal functioning kidneys were observed in group 1 (281.5±45.6) followed by group 2 (204.4±55) and group 3 (157.5±44). Moderate negative correlation was detected between the Tc99m MAG3 clearances of normal kidneys and contralateral renal function (r=-0.5, p<0.001). Conclusion: Normal kidneys can compensate for the loss of contralateral kidney function via increasing their clearances, which seems to be dependent on the residual function of their partner. Camera based Tc 99m MAG3 clearance measurement is an objective method to demonstrate compensatory differences in renal function seen between kidneys with contralateral normofunctioning, hypofunctioning and nonfunctioning partner. Conflict of interest:None declared.