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Ask your administrator if you think this is wrong. ====== MIDBRAIN ====== * MESENCEPHALON; MIDBRAIN * upper and shortest part of brainstem * EXTERNAL FEATURES OR SURFACES * VENTRAL SURFACE * emerges from cerebral hemispheres joins to form * crus cerebri of midbrain * converges downwards to enter * pons * forms posterolateral boundary of * interpeduncular fossa * superficial surface * corrugated by underlying longitudinal fibers * crosses transversely from above downwards by * optic tract , * taenia pontis * superior cerebellar artery , posterior cerebral artery * medial side * groove * occulomotor nerve emerges * dorsal aspect * trochlear nerve emerges * curls around lateral aspect of cerebral peduncles * DORSAL SURFACE * shows four rounded elevations called corpora quadrigemina * separated from each other by * cruciform sulcus * vertical limb of sulcus when * traced above forms a depression * lodges pineal body * traced below becomes continuous with * frenulum veli * median ridge on dorsal surface of superior medullary velum * laterally from colliculi * thick ridges of white matter extend * called brachium * superior brachium * connects superior colliculus to lateral geniculate body * connects inferior colliculus to medial geniculate body * inferior brachium * two superior * superior colliculus * two inferior * inferior colliculus * INTERNAL STRUCTURE * Mid brain divided by coronal plane passing through cerebral aqueduct in to two parts * anterior part or cerebral peduncle * parts from dorsal to ventral * tegmentum * substantia nigra * curved , crescent shaped * pigmented band of grey matter * deeply pigmented nerve cells * contain melanin ( polymerized form of dopamine ) * synthesize dopamine * carried through their axons ( nigrostriatal fibers) * to corpus striatum * iron * spiky process project in to crus cerebri * parts * dorsal part (pars compacta ) - medium sized cells * pars reticularis ( ventral part ) - few cells * intermingled with fibres of crus cerebri * crus cerebri * most anterior part * white matter * descending tracts * connect cerebral cortex to * anterior horn cells of spinal cord * cranial nuclei * pontine nuclei * middle 2/3 of crus * corticospinal * corticonuclear * medial 1/6 th of crus * frontopontine * lateral 1/6 th of crus * temporopontine , parietopontine , occipitopontine * posterior part or tectum * LEVELS OF SECTION * Transverse section of midbrain at level of inferior colliculus * grey matter * centrally * nucleus of trochlear nerve * situated close to median plane * mesencephalic nucleus of trigeminal nerve * more peripheral * beneath the inferior elevations of colliculus * nucleus of inferior colliculus * white matter * central part of tegmentum * decussation of superior cerebellar peduncle * ventral lateral part of tegmentum * medial to lateral * medial lemniscus * trigeminal lemniscus * spinal lemniscus * lateral lemniscus * median longitudinal fasciculus * tectospinal tracts * rubrospinal tracts * transverse section of midbrain at level of superior colliculus * grey matter * more centrally * occulomotor nucleus * edinger westphal nucleus * emerging fibres pass through * medial side of crus cerebri in posterior of interpeduncular fossa * mesencephalic nucleus of trigeminal nerve * more peripheral * nucleus of [[:en:superior_colliculus | superior colliculus ]] * connections * prectectal nucleus * [[:en:red_nucleus | red nucleus ]] * cigar shaped * contains iron * white matter * ventral tegmental decussation * arising from red nuclei * rubrospinal tracts * dorsal tegmental decussation * arising from superior colliculus * tectospinal and tectobulbar tracts * MESENCEPHALON; MIDBRAIN * Interpeduncular fossa * Posterior perforated substance * Oculomotor sulcus * Cerebral peduncle * Cerebral crus * Lateral groove * Tegmentum of midbrain * Trigone of lateral lemniscus * Superior cerebellar peduncle * Frenulum * Tectal plate; quadrigeminal plate * Brachium of inferior colliculus * Brachium of superior colliculus * Inferior colliculus * Superior colliculus * Cerebral peduncle * Base of peduncle * Cerebral crus * Pyramidal tract * Corticospinal fibres * Corticonuclear fibres * Corticopontine fibres * Frontopontine fibres * Occipitopontine fibres * Parietopontine fibres * Temporopontine fibres * Corticoreticular fibres * Substantia nigra * Compact part * Lateral part * Reticular part * Retrorubral part * Tegmentum of midbrain * White substance * Central tegmental tract * Rubro-olivary fibres * Cerebello-olivary fibres * Mesencephalic corticonuclear fibres * Hypothalamospinal fibres * Base of peduncle * Tectopontine tract * Lateral tectobulbar tract * Medial lemniscus * Trigeminal lemniscus * Medial longitudinal fasciculus * Mesencephalic tract of trigeminal nerve * Posterior longitudinal fasciculus; dorsal longitudinal fasciculus [[Schütz]] * Rubronuclear tract * Rubrospinal tract [[Monakow]] * Rubro-olivary tract * Spinal lemniscus; anterolateral tracts; anterolateral systém * Spinothalamic fibres * Spinoreticular fibres * Spinomesencephalic fibres * Spinotectal fibres * Spinoperiaqueductal fibres * Spinohypothalamic fibres * Superior cerebellar peduncle * Decussation of superior cerebellar peduncles * Tectobulbar tract * Tectopontine tract * Tectospinal tract * Pretecto-olivary fibres * Tecto-olivary fibres * Tegmental decussations * Posterior tegmental decussation; dorsal tegmental decussation [[Meynert]] * Anterior tegmental decussation; ventral tegmental decussation [[Forel]] * Corticomesencephalic fibres * Grey substance * Nucleus of oculomotor nerve * Accessory nuclei of oculomotor nerve * Visceral nuclei; autonomic nuclei * Anterior medial nucleus; ventral medial nucleus * Posterior nucleus; dorsal nucleus * Interstitial nucleus [[Cajal]] * Central precommissural nucleus * Nucleus of posterior commissure [[Darkšewič]] * Ventral subdivision * Interstitial subdivision * Dorsal subdivision * Interpeduncular nucleus * Accessory nuclei of optic tract * Posterior nucleus; dorsal nucleus * Lateral nucleus * Medial nucleus * Lateroposterior tegmental nucleus; laterodorsal tegmental nucleus * Mesencephalic nucleus of trigeminal nerve * Nucleus of trochlear nerve * Parabigeminal nucleus * Periaqueductal grey substance; central grey substance * Peripeduncular nucleus * Red nucleus * Magnocellular part * Parvocellular part * Posteromedial part; dorsomedial part * Reticular formation * Sagulum nucleus * Subbrachial nucleus * Anterior tegmental nuclei; ventral tegmental nuclei * Interfascicular nucleus * Parabrachial pigmented nucleus * Paranigral nucleus * Cuneiform nucleus * Subcuneiform nucleus * Pedunculopontine tegmental nucleus * Compact part; compact subnucleus * Dissipated part; dissipated subnucleus * Raphe nuclei * Posterior raphe nucleus; dorsal raphe nucleus * Inferior linear nucleus * Intermediate linear nucleus * Superior linear nucleus * Aqueduct of midbrain; cerebral aqueduct [[Sylvii]] * Opening of aqueduct of midbrain; opening of cerebral aqueduct * Tectum of midbrain * Tectal plate; quadrigeminal plate * Inferior colliculus * Nuclei of inferior colliculus * Central nucleus * External nucleus * Pericentral nucleus * Superior colliculus * Zonal layer; layer i * Superficial grey layer; layer ii * Optic layer; layer iii * Intermediate grey layer; layer iv * Intermediate white layer; layer v * Deep grey layer; layer vi * Deep white layer; layer vii * Brachium of inferior colliculus * Brachium of superior colliculus * Commissure of inferior colliculus * Commissure of superior colliculus * Decussation of trochlear nerve fibres * Reticular nuclei * Cuneiform nucleus * Subcuneiform nucleus * Pedunculopontine tegmental nucleus * Compact part; compact subnucleus * Dissipated part; dissipated subnucleus * Parapeduncular nucleus ===== TERMINOLOGY ===== | 531 | | MESENCEPHALON | MESENCEPHALON; MIDBRAIN | | | 532 | | Fossa interpeduncularis | Interpeduncular fossa | | | 533 | | Substantia perforata posterior | Posterior perforated substance | | | 534 | | Sulcus nervi oculomotorii | Oculomotor sulcus | | | 535 | | Pedunculus cerebri | Cerebral peduncle | | | 536 | | Crus cerebri | Cerebral crus | | | 537 | | Sulcus lateralis mesencephali | Lateral groove | | | 538 | | Tegmentum mesencephali | Tegmentum of midbrain | | | 539 | | Trigonum lemnisci lateralis | Trigone of lateral lemniscus | | | 540 | | Pedunculus cerebellaris superior | Superior cerebellar peduncle | | | 541 | | Frenulum veli medullaris superioris | Frenulum | | | 542 | | Lamina tecti; lamina quadrigemina | Tectal plate; quadrigeminal plate | | | 543 | | Brachium colliculi inferioris | Brachium of inferior colliculus | | | 544 | | Brachium colliculi superioris | Brachium of superior colliculus | | | 545 | | Colliculus inferior | Inferior colliculus | | | 546 | | Colliculus superior | Superior colliculus | | | 547 | | Pedunculus cerebri | Cerebral peduncle | | | 548 | | Basis pedunculi | Base of peduncle | | | 549 | | Crus cerebri | Cerebral crus | | | 550 | | Tractus pyramidalis | Pyramidal tract | | | 551 | | Fibrae corticospinales | Corticospinal fibres | | | 552 | | Fibrae corticonucleares | Corticonuclear fibres | | | 553 | | Tractus corticopontinus | Corticopontine fibres | | | 554 | | Fibrae frontopontinae | Frontopontine fibres | | | 555 | | Fibrae occipitopontinae | Occipitopontine fibres | | | 556 | | Fibrae parietopontinae | Parietopontine fibres | | | 557 | | Fibrae temporopontinae | Temporopontine fibres | | | 558 | | Fibrae corticoreticulares | Corticoreticular fibres | | | 559 | | Substantia nigra | Substantia nigra | | | 560 | | Pars compacta | Compact part | | | 561 | | Pars lateralis | Lateral part | | | 562 | | Pars reticularis | Reticular part | | | 563 | | Pars retrorubralis | Retrorubral part | | | 564 | | Tegmentum mesencephali | Tegmentum of midbrain | | | 565 | | Substantia alba | White substance | | | 566 | | Tractus tegmentalis centralis | Central tegmental tract | | | 567 | | Fibrae rubroolivares | Rubro-olivary fibres | | | 568 | | Fibrae cerebelloolivares | Cerebello-olivary fibres | | | 569 | | Fibrae corticonucleares mesencephali | Mesencephalic corticonuclear fibres | | | 570 | | Fibrae hypothalamospinales | Hypothalamospinal fibres | | | 571 | | Lemniscus lateralis | Base of peduncle | | | 572 | | Tractus tectopontinus | Tectopontine tract | | | 573 | | Tractus tectobulbaris lateralis | Lateral tectobulbar tract | | | 574 | | Lemniscus medialis | Medial lemniscus | | | 575 | | Lemniscus trigeminalis | Trigeminal lemniscus | | | 576 | | Fasciculus longitudinalis medialis | Medial longitudinal fasciculus | | | 577 | | Tractus mesencephalicus nervi trigemini | Mesencephalic tract of trigeminal nerve | | | 578 | | Fasciculus longitudinalis posterior; fasciculus longitudinalis dorsalis [[Schütz]] | Posterior longitudinal fasciculus; dorsal longitudinal fasciculus [[Schütz]] | | | 579 | | Tractus rubronuclearis | Rubronuclear tract | | | 580 | | Tractus rubrospinalis [[Monakow]] | Rubrospinal tract [[Monakow]] | | | 581 | | Tractus rubroolivaris | Rubro-olivary tract | | | 582 | | Lemniscus spinalis; tractus anterolaterales | Spinal lemniscus; anterolateral tracts; anterolateral systém | | | 583 | | Fibrae spinothalamicae | Spinothalamic fibres | | | 584 | | Fibrae spinoreticulares | Spinoreticular fibres | | | 585 | | Fibrae spinomesencephalicae | Spinomesencephalic fibres | | | 586 | | Fibrae spinotectales | Spinotectal fibres | | | 587 | | Fibae spinoperiaqueductales | Spinoperiaqueductal fibres | | | 588 | | Fibrae spinohypothalamicae | Spinohypothalamic fibres | | | 589 | | Pedunculus cerebellaris superior | Superior cerebellar peduncle | | | 590 | | Decussatio pedunculorum cerebellarium superiorum | Decussation of superior cerebellar peduncles | | | 591 | | Tractus tectobulbaris | Tectobulbar tract | | | 592 | | Tractus tectopontinus | Tectopontine tract | | | 593 | | Tractus tectospinalis | Tectospinal tract | | | 594 | | Fibrae pretectoolivares | Pretecto-olivary fibres | | | 595 | | Fibrae tectoolivares | Tecto-olivary fibres | | | 596 | | Decussationes tegmentales | Tegmental decussations | | | 597 | | Decussatio tegmentalis posterior [[Meynert]] | Posterior tegmental decussation; dorsal tegmental decussation [[Meynert]] | | | 598 | | Decussatio tegmentalis anterior [[Forel]] | Anterior tegmental decussation; ventral tegmental decussation [[Forel]] | | | 599 | | Fibrae corticomesencephalicae | Corticomesencephalic fibres | | | 600 | | Substantia grisea | Grey substance | | | 601 | | Nucleus nervi oculomotorii | Nucleus of oculomotor nerve | | | 602 | | Nuclei accessorii nervi oculomotorii | Accessory nuclei of oculomotor nerve | | | 603 | | Nuclei viscerales; nuclei autonomici | Visceral nuclei; autonomic nuclei | | | 604 | | Nucleus anteromedialis | Anterior medial nucleus; ventral medial nucleus | | | 605 | | Nucleus dorsalis | Posterior nucleus; dorsal nucleus | | | 606 | | Nucleus interstitialis [[Cajal]] | Interstitial nucleus [[Cajal]] | | | 607 | | Nucleus precommissuralis centralis | Central precommissural nucleus | | | 608 | | Nucleus commissurae posterioris [[Darkšewič]] | Nucleus of posterior commissure [[Darkšewič]] | | | 609 | | Pars ventralis | Ventral subdivision | | | 610 | | Pars interstitialis | Interstitial subdivision | | | 611 | | Pars dorsalis | Dorsal subdivision | | | 612 | | Nucleus interpeduncularis | Interpeduncular nucleus | | | 613 | | Nuclei accessorii tractus optici | Accessory nuclei of optic tract | | | 614 | | Nucleus posterior | Posterior nucleus; dorsal nucleus | | | 615 | | Nucleus lateralis | Lateral nucleus | | | 616 | | Nucleus medialis | Medial nucleus | | | 617 | | Nucleus tegmentalis posterolateralis | Lateroposterior tegmental nucleus; laterodorsal tegmental nucleus | | | 618 | | Nucleus mesencephalicus nervi trigemini | Mesencephalic nucleus of trigeminal nerve | | | 619 | | Nucleus nervi trochlearis | Nucleus of trochlear nerve | | | 620 | | Nucleus parabigeminalis | Parabigeminal nucleus | | | 621 | | Substantia grisea centralis | Periaqueductal grey substance; central grey substance | | | 622 | | Nucleus peripeduncularis | Peripeduncular nucleus | | | 623 | | Nucleus ruber | Red nucleus | | | 624 | | Pars magnocellularis | Magnocellular part | | | 625 | | Pars parvocellularis | Parvocellular part | | | 626 | | Pars posteromedialis; pars dorsomedialis | Posteromedial part; dorsomedial part | | | 627 | | Formatio reticularis | Reticular formation | | | 628 | | Nucleus saguli; sagulum | Sagulum nucleus | | | 629 | | Nucleus subbrachialis | Subbrachial nucleus | | | 630 | | Nuclei tegmentales anteriores | Anterior tegmental nuclei; ventral tegmental nuclei | | | 631 | | Nucleus interfascicularis | Interfascicular nucleus | | | 632 | | Nucleus pigmentosus parabrachialis | Parabrachial pigmented nucleus | | | 633 | | Nucleus paranigralis | Paranigral nucleus | | | 634 | | Nucleus cuneiformis | Cuneiform nucleus | | | 635 | | Nucleus subcuneiformis | Subcuneiform nucleus | | | 636 | | Nucleus tegmentalis pedunculopontinus | Pedunculopontine tegmental nucleus | | | 637 | | Pars compacta | Compact part; compact subnucleus | | | 638 | | Pars dissipata | Dissipated part; dissipated subnucleus | | | 639 | | Nuclei raphes | Raphe nuclei | | | 640 | | Nucleus raphe posterior | Posterior raphe nucleus; dorsal raphe nucleus | | | 641 | | Nucleus linearis inferior | Inferior linear nucleus | | | 642 | | Nucleus linearis intermedius | Intermediate linear nucleus | | | 643 | | Nucleus linearis superior | Superior linear nucleus | | | 644 | | Aqueductus mesencephali; aqueductus cerebri [[Sylvii]] | Aqueduct of midbrain; cerebral aqueduct [[Sylvii]] | | | 645 | | Apertura aqueductus mesencephali; apertura aqueductus cerebri | Opening of aqueduct of midbrain; opening of cerebral aqueduct | | | 646 | | Tectum mesencephali | Tectum of midbrain | | | 647 | | Lamina tecti; lamina quadrigemina | Tectal plate; quadrigeminal plate | | | 648 | | Colliculus inferior | Inferior colliculus | | | 649 | | Nuclei colliculi inferioris | Nuclei of inferior colliculus | | | 650 | | Nucleus centralis | Central nucleus | | | 651 | | Nucleus externus; nucleus lateralis | External nucleus | | | 652 | | Nucleus pericentralis | Pericentral nucleus | | | 653 | | Colliculus superior | Superior colliculus | | | 654 | | Stratum zonale; lamina i | Zonal layer; layer i | | | 655 | | Stratum griseum superficiale; lamina ii | Superficial grey layer; layer ii | | | 656 | | Stratum opticum; lamina iii | Optic layer; layer iii | | | 657 | | Stratum griseum intermedium; lamina iv | Intermediate grey layer; layer iv | | | 658 | | Stratum medullare intermedium; lamina v | Intermediate white layer; layer v | | | 659 | | Stratum griseum profundum; lamina vi | Deep grey layer; layer vi | | | 660 | | Stratum medullare profundum; lamina vii | Deep white layer; layer vii | | | 661 | | Brachium colliculi inferioris | Brachium of inferior colliculus | | | 662 | | Brachium colliculi superioris | Brachium of superior colliculus | | | 663 | | Commissura colliculi inferioris | Commissure of inferior colliculus | | | 664 | | Commissura colliculi superioris | Commissure of superior colliculus | | | 665 | | Decussatio fibrarum nervorum trochlearium | Decussation of trochlear nerve fibres | | | 666 | | Nuclei reticulares | Reticular nuclei | | | 667 | | Nucleus cuneiformis | Cuneiform nucleus | | | 668 | | Nucleus subcuneiformis | Subcuneiform nucleus | | | 669 | | Nucleus tegmentalis peduncolopontinus | Pedunculopontine tegmental nucleus | | | 670 | | Pars compacta | Compact part; compact subnucleus | | | 671 | | Pars dissipata | Dissipated part; dissipated subnucleus | | | 672 | | Nucleus parapeduncularis | Parapeduncular nucleus | | en/midbrain.txt Last modified: 2023/06/23 06:22by 127.0.0.1