Endogenous bacterial endophthalmitis. A report of 2cases. / Endoftalmitis endógenas bacterianas. A propósito de 2casos.

CLINICAL CASES: The cases are presented on 2patients with bacterial endogenous endophthalmitis. The first one was caused by Streptococcus bovis, developed after colonoscopy, which had a poor outcome and resulted in evisceration. The second case was caused by a methicillin resistant Staphylococcus aureus from an arthrodesis complicated with a para-spinal abscess. It had an excellent visual outcome. DISCUSSION: Bacterial endogenous endophthalmitis is a rare, but serious ocular disease that occurs when bacteria reach the eye via the bloodstream. It requires a very early diagnosis based on the clinical symptoms and patient history. A suitable and specific treatment with intravenous and intravitreal antibiotics may prevent a bad visual prognosis in some cases.

The usefulness of 18F-fluorocholine PET/CT in the detection of recurrence of central nervous system primary neoplasms. / Valor de la PET/TC cerebral con 18F-fluorocolina en la detección de recurrencias de neoplasias primarias del sistema nervioso central.

AIM: To study the usefulness of 18F-fluorocholine (FCH) in detecting the recurrence of primary brain tumours. MATERIAL AND METHODS: A prospective study was conducted on brain PET/CT with FCH for compassionate use in 21 patients with suspected recurrence of a primary brain tumour. The distribution by pathology was: three grade ii astrocytomas, three grade iii astrocytomas, one grade ii oligodendroglioma, three grade iii oligodendrogliomas, one grade iii oligoastrocytoma, four glioblastoma multiform, one gliomatosis cerebri, and five meningiomas. Studies in which there was a visually significant uptake in the brain parenchyma were classified as positive. RESULTS: A total of 17 patients were classified as positive, with the results being confirmed by histology (10 cases) or clinical follow-up and imaging, with no false positives or negatives. The mean SUVmax for positive patients was 8.02 and 0.94 for the negative ones, which was significantly different (P=.003) CONCLUSION: PET/CT with FCH shows encouraging results in the evaluation of patients with suspected recurrence of primary brain neoplasms.

Computing quantitative indicators of structural renal damage in pediatric DMSA scans.

OBJECTIVES: The proposal and implementation of a computational framework for the quantification of structural renal damage from 99mTc-dimercaptosuccinic acid (DMSA) scans. The aim of this work is to propose, implement, and validate a computational framework for the quantification of structural renal damage from DMSA scans and in an observer-independent manner. MATERIALS AND METHODS: From a set of 16 pediatric DMSA-positive scans and 16 matched controls and using both expert-guided and automatic approaches, a set of image-derived quantitative indicators was computed based on the relative size, intensity and histogram distribution of the lesion. A correlation analysis was conducted in order to investigate the association of these indicators with other clinical data of interest in this scenario, including C-reactive protein (CRP), white cell count, vesicoureteral reflux, fever, relative perfusion, and the presence of renal sequelae in a 6-month follow-up DMSA scan. RESULTS: A fully automatic lesion detection and segmentation system was able to successfully classify DMSA-positive from negative scans (AUC=0.92, sensitivity=81% and specificity=94%). The image-computed relative size of the lesion correlated with the presence of fever and CRP levels (p<0.05), and a measurement derived from the distribution histogram of the lesion obtained significant performance results in the detection of permanent renal damage (AUC=0.86, sensitivity=100% and specificity=75%). CONCLUSIONS: The proposal and implementation of a computational framework for the quantification of structural renal damage from DMSA scans showed a promising potential to complement visual diagnosis and non-imaging indicators.

[Interpretation of thyroid incidentalomas in (18)F-FDG PET/CT studies]. / Interpretación de incidentalomas tiroideos en estudios PET/TC con (18)F-FDG.

OBJECTIVE: Thyroid findings or incidentalomas in (18)F-FDG PET/CT studies are relatively frequent, being its clinical significance subject of controversy. The aim of this study was to show our experience in the detection of thyroid incidentalomas by PET/CT studies as well as its follow up. MATERIAL AND METHODS: A retrospective and descriptive review was conducted on patients who had thyroid incidentalomas detected in (18)F-FDG PET/CT studies between June 2010 and March 2013. Patient's medical records were reviewed for age, genre, maximum standardized uptake value (SUVmax), thyroid diseases, TSH and antithyroid antibodies levels, ultrasound, fine-needle aspiration (FNA) and cytology. RESULTS: 4085 PET/CT studies for several purposes were performed. Eighty-three of these studies (2.03%) showed thyroid incidentalomas. Thirty-seven patients showed a diffuse increase of glucose metabolism in the thyroid gland and 46 showed a focal increase of glucose metabolism. Five out of 46 patients with focal uptake were diagnosed of a neoplastic disease by cytology (11%). The SUVmax of malignant pathology did not differ from that of benign thyroid diseases (Mean: 10,26 and 5,92 respectively). CONCLUSION: In our experience, focal thyroid incidentalomas detected in (18)F-FDG PET/CT studies are related to a significant risk of malignancy (11%). Therefore, in these situations, an ultrasound study with fine needle biopsy should be recommended. Moreover, a diffuse increase of glucose metabolism in the thyroid gland is often associated with benign thyroid pathology.

[Utility of early imaging of myocardial innervation scintigraphy in the diagnosis of Lewy Body Dementia]. / Utilidad de la imagen precoz de la gammagrafía de inervación miocárdica en el diagnóstico de la demencia con cuerpos de Lewy.

UNLABELLED: The importance of accurate and early diagnosis of dementia with Lewy bodies (DLB) lies in its pharmacological management. Delayed imaging of cardiac (123)I-MIBG scintigraphy allows differentiation between DLB and other neurodegenerative diseases with cognitive impairment. The aim of this study was to assess the utility of early imaging of cardiac (123)I-MIBG scintigraphy for differentiating DLB from others neurodegenerative disease with cognitive impairment. MATERIAL AND METHODS: We assess retrospectively 106 patients (51 men, mean age 78 years) with cognitive impairment that underwent a cardiac (123)I-MIBG study. Planar images were acquired in anterior view of the thorax 15min (early) and 4h (delayed) after tracer administration. The heart-to-mediastinum ratios (HMR) at 15m (HMR15m) and at 4h (HMR4h) were obtained. RESULTS: After four years, 52 patients were diagnosed of DLB.HMR15m and HMR4h were significantly inferior in DLB respect to the others neurodegenerative diseases (1,27±0,15 vs 1,76±0,15,p<0,05) and (1,14±0,13 vs 1,68±0,19,p<0.01), respectively. The ROC analysis showed a HMR15m cut off point of 1.56 to differentiated DLB from the other dementias with a sensitivity and a specificity of 98%. CONCLUSIONS: Early imaging of cardiac (123)I-MIBG scintigraphy can help to differentiate DLB from other neurodegenerative diseases with cognitive impairment.

[Incidence of focal myocardial (18)F-FDG uptake and correlation with coronary calcifications by PET/CT]. / Incidencia de focos miocárdicos de captación de (18)F-FDG y su relación con la presencia de calcificaciones coronarias por PET/TC.

OBJECTIVE: To evaluate the incidence of (18)F-FDG focal uptake in the myocardium as well as its correlation with coronary vessel calcifications. MATERIAL AND METHODS: A total of 130 patients who underwent an oncological PET/CT study were reviewed retrospectively. Sixty-five had undergone a myocardial perfusion study because of clinical suspicion of coronary artery disease (group 1). There were no significant differences in age and gender regarding another group of the same series (n=65; group 2). Focal myocardial (18)F-FDG uptake and the presence of coronary vessel calcifications were identified by 2 independent observers. RESULTS: Group 1: in 18 out of 65 patients (28%) focal myocardial (18)F-FDG uptake was identified (5 had 2 foci; total: 23 foci). In 43 out of 65 studies (66%), calcification was identified in the coronary vessels. Group 2: in 6 out of 65 patients (9%) focal myocardial (18)F-FDG uptake was identified (1 had 2 foci; total: 7 foci). In 17 out of 65 studies (26%), calcification was identified in the coronary vessels. Comparative analysis: focal myocardial (18)F-FDG uptake and coronary vessel calcifications were more frequent in the group 1 patients (p<0.01). There was no correlation between the presence of coronary vessel calcifications and focal myocardial (18)F-FDG uptake in individual patients in both groups (group 1: p=0.7; group 2: p=0.163). CONCLUSIONS: PET/CT allows simultaneous assessment of focal myocardial (18)F-FDG uptake and myocardial vessel calcifications. Patients with clinical suspicion of coronary artery disease have a higher incidence of focal myocardial (18)F-FDG uptake and coronary calcifications. However, (18)F-FDG focal uptake is often observed in sites remote from those with calcification.

Cardiac sympathetic impairment parallels nigrostriatal degeneration in Probable Dementia with Lewy Bodies.

AIM: Dementia with Lewy Bodies (DLB) must be distinguished from other types of dementia because of important differences in patient management and outcome. Both reduction in cardiac 123I-metaiodobenzilguanidine (MIBG) uptake and decreased 123I-FP-CIT binding in basal ganglia have been described in DLB. The aim of this study was to assess the relationship between cardiac sympathetic activity and nigrostriatal degeneration in patients with probable DLB. METHODS: Twenty-eight patients (15 males; mean age 77 years, range 64-88 years) with clinical international criteria of probable DLB were included in the study. All patients underwent a cardiac MIBG scintigraphy and a FP-CIT SPECT. Global cardiac MIBG uptake was semiquantified by means of heart-to-mediastinum ratio (HMR) (normal >1.56). FP-CIT binding in basal ganglia was calculated and compared with an age-matched control group. The relation between cardiac MIBG uptake and FP-CIT uptake in basal ganglia, and the relationship of these two techniques with distinctive symptoms of DLB, features of past medical history and data from the neuropsychological examination were assessed. RESULTS: Cardiac MIBG uptake was decreased in 23 of 28 patients (HMR=1.32, range 0.95-1.85). The FP-CIT binding in basal ganglia was significantly lower than in control group (2.01±0.5 vs 2.62±0.2, P<0.05). All patients with reduced cardiac HMR showed decreased FP-CIT binding in basal ganglia. There was a positive correlation between the HMR and specific binding ratio of striatum (P<0.01). A high correlation between FP-CIT SPECT and the presence of parkinsonism also was found. No correlation between cardiac MIBG uptake and demographic, clinical or neuropsychological data was found. CONCLUSION: In probable DLB cardiac MIBG uptake and FP-CIT binding in basal ganglia are reduced. The positive correlation between both measures suggests that cardiac sympathetic degeneration and nigrostriatal degeneration parallel similarly in patients with probable DLB.