[Musculoskeletal tumor evaluation with 99mTc-Tetrofosmin]. / 99mTc-Tetrofosmin en la evaluación de tumores musculoesqueléticos.

INTRODUCTION: (99m)Tc-tetrofosmin is an efficient agent as a tumor marker. Several studies have proven its efficiency in detection and localization of tumors of the breast, larynx, thyroid, parathyroid glands, lung, brain, skin, lymphatic and musculoskeletal tissues with a sensitivity and specificity of 95% to 100%. It is used as a predictor of therapy efficacy and to localize remaining and recurrent tissue as well as local and distant extension. OBJECTIVE: To determine the sensitivity, specificity and predictive values of the three-phase 99mTc-Tetrofosmin scan in detection of malignant lesions of the musculoskeletal tissue. METHODS: Seventy-three patients of both genders with suspected malignant musculoskeletal lesions were studied by three-phase (vascular, tissue and delayed images) 99mTc-tectrofosmin scans. RESULTS: One-hundred-percent sensitivity, 67.3% specificity, 55% positive predictive value, and 100% negative predictive value. CONCLUSION: Three-phase 99mTc-tectrofosmin scan is useful in detection of malignant lesions of the musculoskeletal system due to its high sensitivity and positive predictive value. Nevertheless, benign pathology such as active inflammation is a source of false positives and the attending physician must consider the aid of complementary studies such as histopathology.

Cerebral blood flow associated with creative performance: a comparative study.

Creativity is important for social survival and individual wellbeing; science, art, philosophy and technology have been enriched and expanded by this trait. To our knowledge this is the first study probing differences in brain cerebral blood flow (CBF) between highly creative individuals (scientists and/or artists socially recognized for their contributions to their fields with creativity indexes corresponding to the 99% percentile) and average control subjects while performing a verbal task from the Torrance Tests of Creative Thinking. Additionally, we correlated CBF with creativity dimensions such as fluency, originality and flexibility. Subjects with a high creative performance showed greater CBF activity in right precentral gyrus, right culmen, left and right middle frontal gyrus, right frontal rectal gyrus, left frontal orbital gyrus, and left inferior gyrus (BA 6, 10, 11, 47, 20), and cerebellum; confirming bilateral cerebral contribution. These structures have been involved in cognition, emotion, working memory, and novelty response. The score on the three creativity dimensions--fluency, originality, and flexibility--correlated with CBF activation in right middle frontal gyrus and right rectal gyrus (Brodmann Area 6, 11). Moreover, fluency and flexibility strongly correlated with CBF in left inferior frontal gyrus and originality correlated with CBF in left superior temporal gyrus and cerebellar tonsil. These findings suggest an integration of perceptual, volitional, cognitive and emotional processes in creativity. The higher CBF found in particular brain regions of highly creative individuals during the performance of a creative task provides evidence of a specific neural network related to the creative process.

Coexistence of epileptic nocturnal wanderings and an arachnoid cyst.

Episodic nocturnal wanderings (ENWs) have rarely been associated with gross abnormalities of brain structures. We describe the case of a patient with ENWs in coexistence with an arachnoid cyst (AC). The patient was a 15-year-old boy who presented with nocturnal attacks characterized by complex motor behaviors. An MRI revealed a left temporal cyst and a SPECT Tc99 scan showed left temporal hypoperfusion and bilateral frontal hyperperfusion, more evident on the right side. During an all-night polysomnographic recording with audiovisual monitoring, dystonic posture followed by sleepwalking-like behavior was documented. The sleepwalking-like behavior was preceded by a spike discharge over the left frontocentral region with contralateral projection and secondary generalization during stage 2 sleep. Treatment with levetiracetam produced a striking remission of seizures. This supports a conservative management of an AC, considering that it may be an incidental finding. In epileptic patients, an AC may not necessarily be related to the location of the seizure focus.

Correlation between cerebral blood flow and items of the Hamilton Rating Scale for Depression in antidepressant-naive patients.

BACKGROUND: The purpose of this study was to correlate the basal cerebral blood flow (CBF) in patients with major depressive disorder (MDD) with the score for each of the 21 questions in the Hamilton Rating Scale for Depression (HRSD), in order to determine the cerebral regions associated with each item. METHODS: Fourteen antidepressant-naive patients with unipolar depression (DSM-IV criteria for MDD) participated in this study with a HRSD score of >/=20 points. CBF images obtained by SPECT were analyzed by SPM99 software. The significant correlation threshold for a priori regions (frontocortical and limbic regions) was a Z value of at least 2.25 and clusters formed by more than 10 voxels. RESULTS: Items 1, 6, 11 and 20 were positively correlated with right medial frontal gyrus; item 7 was negatively correlated with bilateral medial frontal gyrus. Items 2 and 10 were positively correlated with right anterior and medial cingulate, respectively. Item 5 was negatively correlated with the left amygdala. Item 9 was negatively correlated with bilateral insula, and item 16 with right insula. Items 12 and 14 were positively correlated with right and left precentral frontal gyrus, respectively. LIMITATIONS: The small sample size and only out-patients included in the study. CONCLUSIONS: The frontal cortex plays an important role in the expression of MDD symptoms. Not all the symptoms evaluated correlated with one single structure, which may explain the diverse results reported in the literature. These preliminary results support the necessity of further analyses by symptoms that could provide more specific information on the pathophysiology of MDD.