- A structure composed of a group of fibers, muscular or nervous; a fasciculus. SYN: fasciculus (3) [TA].- aberrant bundles a group, or groups, of fibers from the corticobulbar or corticonuclear tract, directed to each of the motor nuclei of cranial nerves.- atrioventricular b. [TA] the b. of modified cardiac muscle fibers that begins at the atrioventricular node as the trunk of the atrioventricular b. and passes through the right atrioventricular fibrous ring to the membranous part of the interventricular septum where the trunk divides into two branches, the right b. (crus dextrum) of the atrioventricular b. and the left b. (crus sinistrum) of the atrioventricular b.; the two crura ramify in the subendocardium of their respective ventricles. SYN: fasciculus atrioventricularis [TA], atrioventricular band, Gaskell bridge, His band, His b., Keith b., Kent b. (1), Kent-His b., truncus fascicularis atrioventricularis, trunk of atrioventricular b., ventriculonector.- Bachmann b. division of the theoretical anterior internodal tract that continues into the left atrium providing a specialized path for interatrial conduction. The anatomic reality of this structure has been disputed.- Flechsig ground bundles [TA] fasciculus proprius anterior [TA] and fasciculus proprius lateralis [TA]. See fasciculi proprii, under fasciculus.- ground bundles SYN: fasciculi proprii, under fasciculus.- Helweg b. SYN: olivospinal tract.- Helwig b. SYN: olivospinal fibers, under fiber.- His b. SYN: atrioventricular b..- Kent b. 1. SYN: atrioventricular b.. 2. a muscle fiber b. in the mammalian heart below the atrioventricular node; may also occur in humans.- Kent-His b. SYN: atrioventricular b..- lateral ground b. obsolescent. See fasciculi proprii, under fasciculus.- lateral proprius b. SYN: fasciculi proprii, under fasciculus.- left b. of atrioventricular b. [TA] the left limb or branch of the atrioventricular b. that separates from the atrioventricular b. just below the membranous portion of the interventricular septum to descend the septal wall of the left ventricle and begins to ramify subendocardially. SYN: crus sinistrum fasciculi atrioventricularis, left crus of atrioventricular b..- medial forebrain b. [TA] a fiber system coursing longitudinally through the lateral zone (area) of the hypothalamus, connecting the latter reciprocally with the midbrain tegmentum and with various components of the limbic system; it also carries fibers from norepinephrine-containing and serotonin-containing cell groups in the brainstem to the hypothalamus and cerebral cortex, as well as dopamine-carrying fibers from the substantia nigra to the caudate nucleus and putamen. SYN: fasciculus medialis telencephali [TA].- neurovascular b. of Walsh the anatomic structure composed of capsular arteries and veins to the prostate and cavernous nerves that provides the macroscopic landmark used during nerve-sparing radical pelvic surgery.- olfactory b. a fiber system, described by E. Zuckerkandl as “Reichbündel,” descending from the transparent septum in front of the anterior commissure toward the base of the forebrain; it contains precommissural fibers of the fornix, fibers from the septum to the hypothalamus and innominate substance, as well as fibers ascending to the septum and hippocampus from the hypothalamus and midbrain; it bears no special relation to the sense of smell.- Pick b. a b. of nerve fibers recurving rostralward from the pyramidal tract in the medulla oblongata, and believed to consist of corticonuclear fibers.- precommissural b. olfactory b..- predorsal b. SYN: tectospinal tract.- Rathke bundles SYN: trabeculae carneae (of right and left ventricles), under trabecula.- retroflex b. of Meynert SYN: retroflex fasciculus.- right b. of atrioventricular b. [TA] the right leg or branch of the atrioventricular b. that diverges from the left crus just below the membranous portion of the interventricular septum to descend the septal wall of the right ventricle and ramify beneath the endocardium. SYN: crus dextrum fasciculi atrioventricularis [TA], right crus of atrioventricular b..- solitary b. SYN: solitary tract.- tendon b. a group of tendon fibers surrounded by a sheath of irregular connective tissue (peritendineum).- Türck b. SYN: anterior corticospinal tract.- Vicq d'Azyr b. SYN: mammillothalamic fasciculus.
* * *bun·dle 'bən-dəl n a small band of mostly parallel fibers (as of nerve or muscle): FASCICULUS, TRACT
* * *n.a group of muscle or nerve fibres situated close together and running in the same direction; e.g. the atrioventricular bundle.
* * *bun·dle (bunґdəl) a collection of muscle or nerve fibers; see also fasciculus, fiber, lemniscus, tract, and tractus.
Medical dictionary. 2011.