Diagnosis of Regional Cerebral Blood Flow Abnormalities Using Spect: Agreement between Individualized Statistical Parametric Maps and Visual Inspection by Nuclear Medicine Physicians with Different Levels of Expertise in Nuclear Neurology

INTRODUCTION:

Visual analysis is widely used to interpret regional cerebral blood flow (rCBF) SPECT images in clinical practice despite its limitations. Automated methods are employed to investigate between-group rCBF differences in research studies but have rarely been explored in individual analyses.

OBJECTIVES:

To compare visual inspection by nuclear physicians with the automated statistical parametric mapping program using a SPECT dataset of patients with neurological disorders and normal control images.

METHODS:

Using statistical parametric mapping, 14 SPECT images from patients with various neurological disorders were compared individually with a databank of 32 normal images using a statistical threshold of p<0.05 (corrected for multiple comparisons at the level of individual voxels or clusters). Statistical parametric mapping results were compared with visual analyses by a nuclear physician highly experienced in neurology (A) as well as a nuclear physician with a general background of experience (B) who independently classified images as normal or altered, and determined the location of changes and the severity.

RESULTS:

Of the 32 images of the normal databank, 4 generated maps showing rCBF abnormalities (p<0.05, corrected). Among the 14 images from patients with neurological disorders, 13 showed rCBF alterations. Statistical parametric mapping and physician A completely agreed on 84.37% and 64.28% of cases from the normal databank and neurological disorders, respectively. The agreement between statistical parametric mapping and ratings of physician B were lower (71.18% and 35.71%, respectively).

CONCLUSION:

Statistical parametric mapping replicated the findings described by the more experienced nuclear physician. This finding suggests that automated methods for individually analyzing rCBF SPECT images may be a valuable resource to complement visual inspection in clinical practice.     

Multidetector-row computed tomography in evaluation of atherosclerotic carotid plaques complicated with intraplaque hemorrhage

Our aim was to determine the sensitivity and specificity of multidetector-row computed tomography (CT) in detecting atherosclerotic carotid plaques complicated with intraplaque hemorrhage. We examined carotid plaques from 31 patients operated for carotid artery stenosis. Results of preoperative multidetector-row CT analysis of carotid plaques were compared with results of histological analysis of the same plaque areas. Carotid endarterectomy was performed within 1 week of multidetector-row CT. American Heart Association classification of atherosclerotic plaques was applied for histological classification. Median tissue density of carotid plaques complicated with intraplaque hemorrhage was 22 Hounsfield units (HU). Median tissue density of noncalcified segments of uncomplicated plaques was 59 HU (p=0.0062). The highest tissue density observed for complicated plaques was 31 HU. Multidetector-row CT detected plaques complicated with hemorrhage with sensitivity of 100% and specificity of 64.7%, with tissue density of 31 HU as a threshold value. Multidetector-row CT showed a high level of sensitivity and a moderate level of specificity in detecting atherosclerotic carotid plaques complicated with hemorrhage.     

Xanthogranulomatous epididymitis: clinical report and immunohistochemical analysis

Xanthogranulomatous epididymitis is an uncommon non-neoplastic process with destruction of tissue and replacement by striking cellular infiltration of foamy macrophages, dense lymphocytes and plasma cells. We report on a 72-year-old man with a clinical history of inadequately treated arterial hypertension, who presented with a right scrotal mass associated with right scrotal pain for 10 days. Physical examination revealed pyogenic discharge from the hyperemic and edematous scrotum, with normal body temperature. Testicular tumor markers were normal. Ultrasonography (US) of the right testis showed edematous scrotal layers and a heterogeneous area of poorly defined margins within the testis and epididymis. There was minimal hydrocele, and the right funiculus was of normal diameter with no edema or pathologic formation. The progression of clinical findings, inflammatory parameters, US and color Doppler US findings with negative testicular tumor markers indicated surgical treatment. After preoperative treatment, right orchiepididymectomy was performed. Histology confirmed the diagnosis of xanthogranulomatous epididymitis.     

Progression of articular cartilage degeneration after application of muscle stretch

The aim of study was to evaluate the progression of the ankle articular cartilage alterations after a post-immobilization muscle stretching. Twenty-nine Wistar rats were separated into five groups: C--control, S--stretched, SR--stretch recovery, IS--immobilized and stretched, and ISR--immobilized stretched recovery. The immobilization was maintained for 4 weeks and the left ankle was then stretched manually through a full dorsal flexion for 10 times for 60 s with a 30 s interval between each 60 s period, 7 days/week for 3 weeks. The recovery period was of 7 weeks. At the end of the experiment, the left ankles were removed, processed in paraffin, and stained in hematoxylin-eosin and safranin O. Two blinded observers evaluated the articular cartilage using the Mankin grading system (cellularity, chondrocyte cloning, and proteoglycan content) through light microscopy, and performed the morphometry (cellularity, total thickness, non-calcified thickness, and calcified thickness measures). Both the Mankin grading system and the morphometric analysis showed that the ISR group presented the most increased cellularity among the groups. The IS and SR groups showed the highest proteoglycan loss, and the ISR group showed the same content of proteoglycan observed in the C group. No significant differences were found in the chondrocyte cloning, the total cartilage thickness, the non-calcified cartilage thickness, and the calcified cartilage thickness among the groups. The results suggest that the cartilage can recover the proteoglycan loss caused by immobilization and stretching, probably because of the increased chondrocyte density. Therefore, the ankle articular cartilage responded as to repair the metabolic deficits.     

Uliginosin B presents antinociceptive effect mediated by dopaminergic and opioid systems in mice

Previous studies have shown that uliginosin B inhibits dopamine reuptake in rat brain. This compound occurs in Hypericum polyanthemum and H. caprifoliatum for which was reported to have antinociceptive effect sensitive to naloxone. The aim of this study was to assess the antinociceptive effect of uliginosin B and to evaluate the involvement of opioid and dopaminergic receptors activation. Uliginosin B presented antinociceptive effect in hot-plate and abdominal writhing tests, in mice, at doses that did not impair the motor coordination (15 mg/kg, i.p.). Uliginosin B in high dose (90 mg/kg, i.p.) presented ataxic effect in the rotarod apparatus. These effects seem to be mediated by distinct receptors since the effect on the hot-plate was completely abolished by naloxone and sulpiride, but it was unaffected by SCH 23390. On the other hand, the motor impairment induced by uliginosin B was completely prevented by naloxone and partially prevented by sulpiride and SCH 23390. However, the receptors' activation appears to be indirect since uliginosin B did not bind to opioid and dopaminergic receptors. Thus, uliginosin B effects probably are due to its ability to inhibit monoamine reuptake with consequent activation of dopamine receptors and indirect stimulation of opioid system.     

Foamy cell (hibernoma-like) change is a rare histopathological feature in renal cell carcinoma

We report nine patients (seven males and two females, median age 64 years (range 51–79 years)) with a renal cell carcinoma, each of which contained a significant component of neoplastic epithelial cells with a striking microvacuolated (hibernoma-like) cytoplasmic appearance. Tumor sizes ranged from 1.5 to 8.0 cm (mean 4.2 cm, median 4.3 cm). The basic architecture of the tumors was solid-alveolar in two cases (classified as renal cell carcinoma-not otherwise specified (NOS)) and papillary in seven cases (classified as papillary renal cell carcinoma NOS). The nuclear grade according to the Fuhrman grading system was three in all cases. By immunohistochemistry, the cells with microvacuolated cytopasm and significantly expressed adipophilin and anti-mitochondrial antigen in a similar cytoplasmic pattern. On ultrastructural examination, the cytoplasm of the neoplastic epithelial cells was packed with distended mitochondria, most of which displayed lamellated cristae. Numerous microvesicles were dispersed between the mitochondria. No mutations in the succinate dehydrogenase B gene were identified. Based on our findings, we propose that the mechanism behind this phenomenon is an abnormal intracellular processing of lipids. No aggressive behavior was observed in six out of nine patients with available follow-up information.