Biomedical subjects

Bruno Nazarian

Publications and source records attributed to Bruno Nazarian.

3 recordsLinked to original sources

PubMed2004

Functional anatomy of the attentional modulation of time estimation.

Attention modulates our subjective perception of time. The less we attend to an event's duration, the shorter it seems to last. Attention to time or color stimulus attributes was modulated parametrically in an event-related functional magnetic resonance imaging study. Linear increases in task performance were accompanied by corresponding increases in brain activity. Increasing attention to time selectively increased activity in a corticostriatal network, including pre-supplementary motor area and right frontal operculum. Increasing attention to color selectively increased activity in area V4. By identifying areas whose activity was specifically modulated by attention to time, we have defined the core neuroanatomical substrates of timing behavior.

Adult↗

PubMed2004

The role of human left superior parietal lobule in body part localization.

Electrophysiological data in primates suggest that the superior parietal lobule integrates the position of the limbs to construct complex representations of postures. Although in humans the neural basis of these mechanisms remains largely unknown, neuropsychological studies have implicated left superior parietal regions. We devised a simple functional magnetic resonance imaging paradigm aimed at exploring this hypothesis in healthy humans. Strong activation was obtained within the left but not the right superior parietal lobule, providing additional evidence that this structure may play a key role in body part localization processing.

Adult↗

PubMed2002

Virtual laryngotracheal endoscopy based on geometric surface modeling using spiral computed tomography data.

This prospective study describes the clinical utility of virtual endoscopy based on geometric surface modeling of the laryngotracheal lumen. Eighteen children with dyspnea related to either subglottic angioma (n = 5) or laryngotracheal stenosis (n = 13) were included. All patients underwent video-recorded operative endoscopy, spiral computed tomography, and 3-dimensional reconstruction of the laryngotracheal lumen. Modeling was achieved by contour detection on spiral computed tomographic images and reconstruction using a geometric shape-recognition algorithm. The generated surface was used for diagnosis and measurement using interactive and automatic tools. Findings of virtual endoscopy and operative endoscopy were compared. Virtual endoscopy confirmed narrowing of the airway in all cases. In 9 cases, high-grade stenosis prevented complete operative endoscopy, but virtual endoscopy allowed accurate assessment and measurement of the stenosis. The findings of operative and virtual endoscopy were concordant in 9 cases. We conclude that surface modeling provides valuable information for preoperative evaluation of laryngotracheal narrowing. The ability to assess extraluminal anatomy provides a clearer picture of overall disease involvement. In the future, virtual endoscopy will probably be used in conjunction with operative endoscopy for therapeutic decision-making. Noninvasive virtual endoscopy could become an alternative to traditional endoscopy under general anesthesia for therapeutic follow-up.

Adolescent↗