| Macewen's triangle | A triangle formed by the root of the zygomatic arch, the posterior wall of the bony external acoustic meatus, and an imaginary line connecting the extremities of the first two lines; used as a guide in mastoid operations. Synonym: Macewen's triangle. (05 Mar 2000) |
|---|---|
| palatal triangle | A triangular area bounded by the greatest transverse diameter of the palate and by lines converging from its extremities to the alveolar point. Synonym: trigonum palati. (05 Mar 2000) |
| Garland's triangle | A triangular area of relative resonance in the lower back near the spine, found in the same side as a pleural effusion. (05 Mar 2000) |
| Malgaigne's triangle | A space bounded by the superior belly of the omohyoid muscle, anterior border of the sternocleidomastoid, and posterior belly of the digastric; it contains the bifurcation of the common carotid artery. Synonym: trigonum caroticum, fossa carotica, Gerdy's hyoid fossa, Malgaigne's fossa, Malgaigne's triangle, superior carotid triangle. (05 Mar 2000) |
| Marcille's triangle | An area bounded by the medial border of the psoas major, the lateral margin of the vertebral column, and the iliolumbar ligament below; it is crossed by the obturator nerve. (05 Mar 2000) |
| paravertebral triangle | A triangular patch of dullness at the base of the chest alongside the spinal column, on the side opposite a pleural effusion. Synonym: paravertebral triangle. (05 Mar 2000) |
| carotid triangle | A space bounded by the superior belly of the omohyoid muscle, anterior border of the sternocleidomastoid, and posterior belly of the digastric; it contains the bifurcation of the common carotid artery. Synonym: trigonum caroticum, fossa carotica, Gerdy's hyoid fossa, Malgaigne's fossa, Malgaigne's triangle, superior carotid triangle. (05 Mar 2000) |
| vesical triangle | A triangular smooth area at the base of the bladder between the openings of the two ureters and that of the urethra. Synonym: trigonum vesicae, Lieutaud's body, Lieutaud's triangle, Lieutaud's trigone, vesical triangle. (05 Mar 2000) |
| Reil's triangle | A triangular area on the lateral surface of the caudal half of the mesencephalon, bordered caudally by the slight prominence of the lateral lemniscus, dorsally by the base of the inferior colliculus and the brachium of the superior colliculus, and ventrally by the crus cerebri. Synonym: Reil's triangle, triangle of fillet, trigone of fillet, trigonum lemnisci. (05 Mar 2000) |
| cephalic triangle | A triangle on the cranium formed by lines connecting the metopion, the pogonion, and the occipital point. (05 Mar 2000) |
| Gombault's triangle | A compact bundle composed of descending branches of posterior root fibres located near the border between the fasciculi gracilis and cuneatus of the cervical and thoracic spinal cord; it corresponds to the septomarginal fasciculus, Hoche's tract, or oval area of Flechsig in the lumbar, and to the triangle of Philippe-Gombault in the sacral spinal segments; like these, it can be demonstrated only in cases of demyelination resulting from dorsal root lesions. Synonym: fasciculus semilunaris, fasciculus interfascicularis, comma bundle of Schultze, comma tract of Schultze, interfascicular fasciculus. (05 Mar 2000) |
| cervical triangle | Any of the triangles of the neck. (05 Mar 2000) |
| Grocco's triangle | A triangular patch of dullness at the base of the chest alongside the spinal column, on the side opposite a pleural effusion. Synonym: paravertebral triangle. (05 Mar 2000) |
| Grynfeltt's triangle | A triangular space bounded above by the end of the last rib and the serratus posterior inferior muscle, anteriorly by the internal oblique, and posteriorly by the quadratus lumborum; lumbar hernia occurs in this space. Synonym: Lesshaft's triangle. (05 Mar 2000) |
| Petit's lumbar triangle | An area in the posterior abdominal wall bounded by the edges of the latissimus dorsi and external oblique muscles and the iliac crest; herniations occasionally occur here. Synonym: trigonum lumbale, Petit's lumbar triangle. (05 Mar 2000) |