圖1 (f)。小腦總花梗。A，腦幹的前視圖。每張3-D插圖都附有標簽的2-D插圖。橋橫纖維在三叉神經與橋前外側交界處聚集形成小腦中梗。小腦中梗向背側略向尾側進入小腦，位於小腦和腦橋之間的角裂處，稱為橋小腦裂。位於皮質脊髓束前方的橋橫纖維稱為橋淺橫纖維，分為兩部分:位於三叉神經吻側的是橋淺上橫纖維，位於三叉神經尾側的是橋淺下橫纖維。B，左側淺層橋突橫向纖維被切除，露出橋突深層橫向纖維。淺層上、下層橋突橫纖維在右半腦橋皮質脊髓束的前方，深層橋突橫纖維在左半腦橋皮質脊髓束的後方。C，兩邊的橋橋麵橫向纖維都被切除了。 The middle cerebellar peduncle is situated lateral to the inferior cerebellar peduncle. D, posterior view of the inferior cerebellar peduncle in another specimen. Part of the cerebellum and the cuneate and gracile fasciculi in the left dorsal medulla have been removed. The inferior cerebellar peduncle ascends in the dorsolateral medulla, dorsal to the olive, lateral to the gracile and cuneate tubercles, and dorsolateral to the trigeminal spinal tract. At the level of the lateral recess, the inferior cerebellar peduncle ascends deep to the stria medullaris and dorsal cochlear nucleus and turns dorsally to reach the cerebellum. It is crossed ventromedially by the intrapontine segment of the facial nerve and dorsolaterally by the vestibulocochlear nerve. E, lateral view of the left inferior cerebellar peduncle in another specimen. Some left transverse pontine and middle cerebellar peduncle fibers have been removed to expose the inferior cerebellar peduncle. The inferior cerebellar peduncle passes dorsal to the olive and medial to the flocculus to reach the cerebellum. It surrounds the trigeminal nerve within the pons and mixes with fibers of the middle cerebellar peduncle. The inferior cerebellar peduncle within the cerebellum courses in a dorsomedial direction and passes dorsal to the upper two-thirds of the dentate nucleus and its hilus to reach the cerebellar vermis. F, left lateral view of a DTI showing the inferior cerebellar peduncle connecting the spinal cord and cerebellum. Cent., central; Cer., cerebellar; Cer. Pont., cerebellopontine; Coch., cochlear; Coll., colliculus; Cort., cortico; Decuss., decussation; Dent., dentate; Dors., dorsal; DTI, diffusion tensor imaging; Fiss., fissure; Flocc., flocculus; Gl., gland; Inf., inferior; Junc., junction; Lat., lateral; Lemn., lemniscus; Lob., lobule; Med., medial; Mid., middle; Nucl., nucleus; Ped., peduncle; Pon. Mes., pontomesencephalic; Preculm., preculminate; Rec., recess; Spin., spinal; STN, subthalamic nucleus; Sup., superior; Superf., superficial; TPF, transpontine fibers; Tr., tract; TST, trigeminal spinal tract; Tub., tubercle; Vent., ventral. (Images courtesy of AL Rhoton, Jr.)

圖1 (G-K)。小腦總花梗。G，另一個標本的後視圖。右小腦被切除，隻剩下齒狀核。左小腦下梗正好穿過左齒狀核的外側。齒狀核和其他小腦深部核的門位於小腦下梗的內側和下方。H，另一個標本的左側側麵圖。切除部分小腦下梗，顯露小腦上梗與齒狀核的關係。小腦下足梗的吻側緣延伸到小腦前裂的最深處，下緣延伸到小腦初級裂的最深處。鎖門和中央小葉位於小腦上梗的背側。 The superior cerebellar peduncle is located medial to the middle and inferior cerebellar peduncles. The lateral lemniscus, which ascends lateral to the superior cerebellar peduncle, is exposed above the trigeminal nerve. I, left lateral view of another dissection. The inferior cerebellar peduncle has been removed to expose the superior cerebellar peduncle, which connects the dentate nucleus to the red nucleus and thalamus. J, the left superior cerebellar peduncle and dentate nucleus have been removed to expose the medial surface of the superior cerebellar peduncle and dentate nucleus in the right lateral wall of the fourth ventricle. The superior cerebellar peduncle forms the lateral wall of the superior half of the fourth ventricle. K, posterior surface of another specimen showing the decussation of the superior cerebellar peduncle. The superior and inferior colliculi, cerebral aqueduct, and left thalamus have been removed to expose the decussation of the superior cerebellar peduncle and the left subthalamic and red nuclei. The decussation of the superior cerebellar peduncle is located at the level of the inferior colliculus. The ventral fibers of the superior cerebellar peduncle cross first and are located in the caudal part in the decussation. The dorsal fibers cross last and are located in the rostral part of the decussation. The most dorsal fibers continue without crossing. The most ventral fibers of the superior cerebellar peduncle are located at the caudal-most point of the decussation. After decussating, the superior cerebellar peduncle fibers turn laterally to reach the red nucleus, where they form the dorsal capsule of the red nucleus before reaching the thalamus. Cent., central; Cer., cerebellar; Cer. Pont., cerebellopontine; Coch., cochlear; Coll., colliculus; Cort., cortico; Decuss., decussation; Dent., dentate; Dors., dorsal; DTI, diffusion tensor imaging; Fiss., fissure; Flocc., flocculus; Gl., gland; Inf., inferior; Junc., junction; Lat., lateral; Lemn., lemniscus; Lob., lobule; Med., medial; Mid., middle; Nucl., nucleus; Ped., peduncle; Pon. Mes., pontomesencephalic; Preculm., preculminate; Rec., recess; Spin., spinal; STN, subthalamic nucleus; Sup., superior; Superf., superficial; TPF, transpontine fibers; Tr., tract; TST, trigeminal spinal tract; Tub., tubercle; Vent., ventral. (Images courtesy of AL Rhoton, Jr.)

圖2。腦幹的纖維束。A，左側側視圖。橋突橫向纖維和部分橋突皮質束已被切除，露出內側和外側lemmase。外側係索位於內側係索和小腦上梗的外側。B，另一個標本的側視圖。暴露內側係索和內側縱束。內側密管起於纖細結節和楔形結節，向上將腦幹分為腹側和背側部分，並在丘腦中傳遞。在髓質中，內側丘係位於髓質腹側的皮質脊髓束形成的金字塔的後麵。橄欖位於內側基板外側。 In the pons, the medial lemniscus in the lateral view is concave ventrally. In the midbrain, it ascends dorsal to the cerebral peduncle where its fibers intermingle with the substantia nigra. The medial longitudinal fasciculus curves ventrally at the lower edge of the facial colliculus and passes ventral to the hypoglossal triangle. It crosses the medial lemniscus at the level of the gracile and cuneate tubercles and descends in the ventral funiculus of the spinal cord. C, anterior view showing the relationships of the cerebral peduncle, medial lemniscus, and corticospinal tract in the pons. The ventral fiber tracts in the left half of the pons have been removed to expose the medial lemniscus. In the midbrain, the frontopontine fibers (green) are in the medial one-third, the temporoparieto-occipitopontine fibers (blue) are in the lateral one-third, and the corticospinal and corticobulbar tracts (red) are in the middle one-third of the cerebral peduncle. D, posterior view of the medial longitudinal fasciculus and the trigeminal mesencephalic and spinal tracts. Part of the dorsal pons and midbrain have been removed to expose the left medial lemniscus. The medial longitudinal fasciculus courses adjacent the midline near the floor of the fourth ventricle and connects to the trochlear nucleus at the level of the lower half of the inferior colliculus. The medial longitudinal fasciculus passes medial to the abducens nucleus and intrapontine segment of the facial nerve. The trigeminal nerve, after reaching its motor and main sensory nuclei, divides into the rostrally directed trigeminal mesencephalic tract and the caudally directed spinal tract. E, DTI, lateral view, showing the corticospinal tract, middle cerebellar peduncle, and medial lemniscus. F, DTI, lateral view of the medial longitudinal fasciculus. G, posterior view of the central tegmental tract, medial lemniscus, and medial longitudinal fasciculus. Parts of the dorsal pons and midbrain have been removed leaving the right central tegmental tract that connects the red nucleus and the olive. In the midbrain, the central tegmental tract originates from the dorsomedial part of the red nucleus and descends ipsilaterally between the superior cerebellar peduncle laterally, medial longitudinal fasciculus medially, and medial lemniscus ventrally. At the level of the facial colliculus, the central tegmental tract courses medial to the intrapontine segment of the facial nerve and lateral to the intrapontine segment of the abducens nerve to terminate in the olive. Cer., cerebellar, cerebral; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; DTI, diffusion tensor imaging; Flocc., flocculus; Fr. Pon., frontopontine; Hypo., hypoglossal; Inf., inferior; Junc., junction; Lat., lateral; Lemn., lemniscus; Lim., limitans; Mam., mammillary; Med., medial; Mid., middle; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Pon. Med., pontomedullary; Pon. Mes., pontomesencephalic; Seg., segment; Spin., spinal; Subst., substantia; Sulc., sulcus; Sup., superior; TMT, trigeminal mesencephalic tract; TPO Pon., temporoparieto-occipitopontine; Tr., tract; TST, trigeminal spinal tract; Tub., tubercle. (Images courtesy of AL Rhoton, Jr.)

圖3 (a e)。中腦。A，左側側視圖。中腦與上麵的間腦由視束和腦梗之間的溝隔開，與下麵的腦橋由橋腦腦溝隔開。B，內側係索將中腦分為腹側和背側。被蓋(紅色核)和頂蓋(四頭板)位於中腦背側，腦梗位於中腦腹側。外側中腦溝沿內側係索外側邊緣延伸(中斷的綠線)。C，外側中腦溝在中腦表麵，位於腦梗和外側腦丘之間，從上方內側膝狀體延伸到下方的橋腦溝。外側中腦溝沿內側腦丘外側邊緣延伸。D，當以與表麵成直角的角度進入外側中腦溝時，遇到的結構是三叉神經中腦和中央被蓋束、紅核、小腦上梗交叉、中線的動眼核和滑車核。 The red nucleus extends upward from the midlevel of the inferior colliculus to the level of the lateral wall of the third ventricle. The superior cerebellar peduncle decussates caudal to the red nucleus. E, left lateral view of the ventral and dorsal midbrain. Part of the cerebral peduncle and the left thalamus have been removed to expose the subthalamic nucleus and substantia nigra. The cerebral peduncle is in the ventral midbrain and the tegmentum (red nucleus) and tectum (quadrigeminal plate) are in the dorsal midbrain. The substantia nigra is located just dorsal the cerebral peduncle and along the ventral surface of the medial lemniscus. The medial lemniscus passes ventrolateral to the red nucleus to reach the thalamus. Ant., anterior; Cap., capsule; Cer., cerebellar, cerebral; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; Decuss., decussation; Dors., dorsal; Fac., facial; Fasc., fasciculus; Fr. Pon., frontopontine; Gen., geniculate; Gl., gland; Inf., inferior; Int., internal; Interped., interpeduncular; Lat., lateral; Lemn., lemniscus; Mam., mammillary; Med., medial, medullaris; Mes., mesencephalic; Mid., middle; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Perioc., perioculomotor; Pon., ponto; Quad., quadrigeminal; Retro., retroflexus; Rt., right; Seg., segment; Spin., spinal; STN, subthalamic nucleus; Str., stria; Subst., substantia; Sulc., sulcus; Sup., superior; Teg., tegmentum; Tent., tentorium; Thal., thalami, thalamic; TMT, trigeminal mesencephalic tract; Tr., tract; Vent., ventral. (Images courtesy of AL Rhoton, Jr.)

圖3 (f - k)。中腦。F，中腦被蓋左側側麵圖。切除左側中腦背側結構，露出右側被蓋中腦。動眼肌核位於上丘下半部分和下丘上半部分的中線附近，滑車核位於下丘下半部分的水平。紅色核從下丘的中段延伸到第三腦室的側壁。小腦上梗交叉位於紅核的尾部，位於下丘的水平。G,側麵圖。外側中腦溝位於內側腦丘外側緣外側(綠線中斷)。圖示中腦背側(藍色箭頭)和腹側(黃色箭頭)的入路。 H, midbrain axial section. The lateral mesencephalic sulcus is located lateral to the lateral edge of the medial lemniscus, the border between the ventral and dorsal midbrain. Entry into the lateral mesencephalic sulcus at a right angle (blue interrupted line) to the tectal surface (white interrupted line) reaches the dorsal midbrain. Angling 45° forward (green interrupted line) will reach the medial lemniscus. The substantia nigra is located along the anterior surface of the medial lemniscus. I, enlarged view of the midbrain. The medial longitudinal fasciculus located ventrolateral to the oculomotor nucleus ascends to mix with the intramesencephalic segment of the oculomotor nerve, and ends in the interstitial nucleus located rostral to the cerebral aqueduct. The oculomotor and trochlear nuclei in the midbrain are located between the cerebral aqueduct dorsally and the decussation of the superior cerebellar peduncle ventrally. The trochlear nerve is the only cranial nerve originating from the dorsal surface of the brainstem. J, left retrosigmoid surgical view of the brainstem. The lateral mesencephalic sulcus is located between the cerebral peduncle and lateral lemniscus. K, the same brainstem shown in J. The lateral mesencephalic sulcus has been preserved. The long tracts in the midbrain have been exposed. Ant., anterior; Cap., capsule; Cer., cerebellar, cerebral; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; Decuss., decussation; Dors., dorsal; Fac., facial; Fasc., fasciculus; Fr. Pon., frontopontine; Gen., geniculate; Gl., gland; Inf., inferior; Int., internal; Interped., interpeduncular; Lat., lateral; Lemn., lemniscus; Mam., mammillary; Med., medial, medullaris; Mes., mesencephalic; Mid., middle; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Perioc., perioculomotor; Pon., ponto; Quad., quadrigeminal; Retro., retroflexus; Rt., right; Seg., segment; Spin., spinal; STN, subthalamic nucleus; Str., stria; Subst., substantia; Sulc., sulcus; Sup., superior; Teg., tegmentum; Tent., tentorium; Thal., thalami, thalamic; TMT, trigeminal mesencephalic tract; Tr., tract; Vent., ventral. (Images courtesy of AL Rhoton, Jr.)

圖3(幫)。中腦。左，頂板後視圖，以及球上和球下安全進入區(斷續線)。小腦和左丘腦被切除了。橫丘上切口位於上丘上緣上方。枕下切口橫切於滑車神經和下丘下緣之間。如果橫切口向外側延伸過遠，小腦上梗和外側丘將被分割。M，後視圖，進一步剝離頂板。部分上丘和下丘被切除以顯露導槽，導槽是位於上丘和下丘入路腹側邊界的一個重要標誌。N，進一步剝離頂板。 The right red nucleus is exposed while preserving the superior and inferior colliculi on the left side. O, posterior view. The red nucleus extends from the midlevel of the inferior colliculus to the lateral wall of the third ventricle. An incision extending laterally from the midline encounters the habenula, trigeminal mesencephalic tract, central tegmental tract, and red nucleus as the incision is extended from dorsal to ventral. The decussation of the superior cerebellar peduncle is positioned caudal to the red nucleus and at the level of the inferior colliculus. P, posterior view of the midbrain tegmentum on the left side. The oculomotor nucleus is located at the level of the lower half of the superior colliculus and the upper half of the inferior colliculus. The trochlear nucleus is located caudal to the oculomotor nucleus at the level of the lower half of the inferior colliculus. The medial longitudinal fasciculus connects these cranial nuclei. Extending the infracollicular incision deeper than the aqueduct from dorsal to ventral will cross the trochlear nuclei, medial longitudinal fasciculus, and decussation of the superior cerebellar peduncle. Ant., anterior; Cap., capsule; Cer., cerebellar, cerebral; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; Decuss., decussation; Dors., dorsal; Fac., facial; Fasc., fasciculus; Fr. Pon., frontopontine; Gen., geniculate; Gl., gland; Inf., inferior; Int., internal; Interped., interpeduncular; Lat., lateral; Lemn., lemniscus; Mam., mammillary; Med., medial, medullaris; Mes., mesencephalic; Mid., middle; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Perioc., perioculomotor; Pon., ponto; Quad., quadrigeminal; Retro., retroflexus; Rt., right; Seg., segment; Spin., spinal; STN, subthalamic nucleus; Str., stria; Subst., substantia; Sulc., sulcus; Sup., superior; Teg., tegmentum; Tent., tentorium; Thal., thalami, thalamic; TMT, trigeminal mesencephalic tract; Tr., tract; Vent., ventral. (Images courtesy of AL Rhoton, Jr.)

圖3 q - t)(。中腦。Q，丘腦切除後的後視圖。在中腦，內側係索向腹外側上升至紅核，向外側上升至丘腦下核，進入丘腦。紅色核從下丘的中段延伸到第三腦室的側壁。丘腦下核位於紅色核的腹側和內囊的背內側。其他標記的結構是後屈束，它沿著紅色核的背內側延伸並連接著韁肌和踝間核，乳丘腦束，連接著乳體和丘腦前核，以及連接韁肌和中隔區域的丘腦髓質紋。R，踝間窩前視圖。周動眼神經安全進入區位於外側皮質脊髓束內側邊緣和內側動眼神經出口點之間。切口向內側傾斜過大會損傷動眼神經的腦內段，向外側傾斜過會進入皮質脊髓束。 S, further dissection. The perioculomotor entry will encounter the red nucleus just behind the medial lemniscus. T, left lateral view. The intramesencephalic segment of the oculomotor nerve passes medial to the red nucleus and exits the interpeduncular fossa. The red nucleus is located dorsal to the exit point of the oculomotor nerve from the brainstem. The surgical routes through the perioculomotor zone to the ventral (yellow arrow) and dorsal (blue arrow) midbrain are shown. Ant., anterior; Cap., capsule; Cer., cerebellar, cerebral; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; Decuss., decussation; Dors., dorsal; Fac., facial; Fasc., fasciculus; Fr. Pon., frontopontine; Gen., geniculate; Gl., gland; Inf., inferior; Int., internal; Interped., interpeduncular; Lat., lateral; Lemn., lemniscus; Mam., mammillary; Med., medial, medullaris; Mes., mesencephalic; Mid., middle; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Perioc., perioculomotor; Pon., ponto; Quad., quadrigeminal; Retro., retroflexus; Rt., right; Seg., segment; Spin., spinal; STN, subthalamic nucleus; Str., stria; Subst., substantia; Sulc., sulcus; Sup., superior; Teg., tegmentum; Tent., tentorium; Thal., thalami, thalamic; TMT, trigeminal mesencephalic tract; Tr., tract; Vent., ventral. (Images courtesy of AL Rhoton, Jr.)

圖4(模擬)。腦橋。A，麵丘的後視圖。第四腦室室管膜和麵丘周圍的白質被切除。麵丘覆蓋在麵神經的外展核和橋突內段。外展核位於地板表麵腹側的中位。麵神經中間溝和外展神經核之間的內側縱束和橋膜內段。B，麵丘後外側視圖。藍色箭頭表示的是麵神經和三叉神經變成腦橋內神經的地方。麵核位於外展核的腹外側和三叉神經脊髓束的腹內側。 The initial intrapontine segment of the facial nerve extends dorsomedially toward the floor of the fourth ventricle, curves around the lower, medial, and upper edges of the abducens nucleus, and continues ventrolaterally along the medial side of the trigeminal spinal tract to exit the pons. C, left posterolateral view of another specimen after removing the left facial nerve. The intrapontine segment of the abducens nerve originates from the ventral face of its nucleus and proceeds anteriorly through the medial lemniscus and lateral to the corticospinal tract to exit the ventral pons. D, posterior view of another specimen. The dorsal cochlear nucleus sits on the dorsal surface of the inferior cerebellar peduncle, where it forms a smooth prominence called the auditory tubercle. The ventral cochlear nucleus is located on the lateral surface of the inferior cerebellar peduncle. The intrapontine segment of the vestibulocochlear nerve passes dorsal to the trigeminal spinal tract. Amb., ambiguus; Attach., attachment; Cer., cerebellar; CN, cranial nerve; Coch., cochlear; Coe., coeruleus; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; Cun., cuneate; Dors., dorsal; Fac., facial; Flocc., flocculus; Fren., frenulum; Hypo., hypoglossal; Inf., inferior; Intrapon., intrapontine; Junct., junction; Lat., lateral; Lemn., lemniscus; Limit., limitans; Med., medial, median; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Pon., pontine; Post., postrema; Rec., recess; Seg., segment; Spin., spinal; Sulc., sulcus; Sup., superior; Tent., tentorium; TMT, trigeminal mesencephalic tract; Tr., tract; Triang., triangle; TST, trigeminal spinal tract; Tub., tubercle; Vent., ventral; Vest., vestibular. (Images courtesy of AL Rhoton, Jr.)

圖4 (eg)。腦橋。E，另一個標本的前外側視圖。三叉神經進入區(斷線)位於三叉神經和麵神經之間。F，另一個標本的腋窩周圍區斜視。左側小腦和部分腦幹被切除，以顯示三叉神經脊髓束與顱神經之間的關係。藍色箭頭表示三叉神經離開腦幹的點，藍色斷線表示垂直的三叉神經周圍切口。三叉神經脊髓束在腦橋中段向尾側彎曲，向下延伸至脊髓。三叉神經脊髓束向脊神經7、9、10、11和12的腦橋內節段背側下行，並向脊神經8的腹側下行。G，另一個標本的乙狀結腸後切口的左側視圖。 The blue arrow shows the point where the facial and trigeminal nerves become intrapontine. The important structures in the peritrigeminal zone are the corticospinal tract anteromedially, the intrapontine segment of the posterior trigeminal root superiorly, the trigeminal motor and main sensory nuclei, intrapontine segment of the facial nerve, and trigeminal spinal tract posteromedially, and the ventral cochlear nucleus, and intrapontine segment of the abducens nerve inferiorly. Amb., ambiguus; Attach., attachment; Cer., cerebellar; CN, cranial nerve; Coch., cochlear; Coe., coeruleus; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; Cun., cuneate; Dors., dorsal; Fac., facial; Flocc., flocculus; Fren., frenulum; Hypo., hypoglossal; Inf., inferior; Intrapon., intrapontine; Junct., junction; Lat., lateral; Lemn., lemniscus; Limit., limitans; Med., medial, median; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Pon., pontine; Post., postrema; Rec., recess; Seg., segment; Spin., spinal; Sulc., sulcus; Sup., superior; Tent., tentorium; TMT, trigeminal mesencephalic tract; Tr., tract; Triang., triangle; TST, trigeminal spinal tract; Tub., tubercle; Vent., ventral; Vest., vestibular. (Images courtesy of AL Rhoton, Jr.)

圖4(設定h)。腦橋。H腦幹後表麵和第四腦室底。第四腦室的底部在中線被中間溝隔開。溝界限，另一個縱向溝，沿地板延伸至中溝外側。地板分為三個部分:上部或橋狀部分，中間或連接部分，下部或髓狀部分。上中央凹位於麵丘的外側，下中央凹位於舌下三角的外側。中腦，腦橋和髓質後視圖。三叉神經有3個感覺核:主要感覺核位於運動核的外側，三叉中腦核隨其神經束上升至中腦，三叉脊髓核隨其神經束下降至上脊髓。三叉中腦束在外側小腦上梗和內側溝界線之間上升，並在橋上端和中腦向中線彎曲。 The central tegmental descends deep to the trigeminal mesencephalic tract. The trigeminal mesencephalic and central tegmental tracts are located deep to the locus coeruleus. The inferior cerebellar peduncle ascends just lateral to the cuneate fasciculus. Amb., ambiguus; Attach., attachment; Cer., cerebellar; CN, cranial nerve; Coch., cochlear; Coe., coeruleus; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; Cun., cuneate; Dors., dorsal; Fac., facial; Flocc., flocculus; Fren., frenulum; Hypo., hypoglossal; Inf., inferior; Intrapon., intrapontine; Junct., junction; Lat., lateral; Lemn., lemniscus; Limit., limitans; Med., medial, median; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Pon., pontine; Post., postrema; Rec., recess; Seg., segment; Spin., spinal; Sulc., sulcus; Sup., superior; Tent., tentorium; TMT, trigeminal mesencephalic tract; Tr., tract; Triang., triangle; TST, trigeminal spinal tract; Tub., tubercle; Vent., ventral; Vest., vestibular. (Images courtesy of AL Rhoton, Jr.)

圖4 (J-L)。腦橋。J,後視圖。上中央凹呈三角形。三角形的頂點位於地板上部最外側的位置。它的上外側邊緣由小腦上梗構成，下外側邊緣由前庭區構成，內側底部由溝限肌構成。上中央凹三角形的上外側邊緣是三叉神經運動核和主要感覺核(黃圈)的深部位置的標誌。上中央凹三角形的頂端與麵丘的吻側邊緣位於同一橫向水平麵上。麵丘的外側邊界由溝限肌構成，內側邊界由內側縱束構成。K，麵表麵後視圖(綠色間斷線)。 The suprafacial approach is limited rostrally by the frenulum veli through which the trochlear nerve passes, caudally by the superior intrapontine segment of the facial nerve forming the upper edge of the facial colliculus, medially by the medial longitudinal fasciculus, and laterally by the sulcus limitans. L, enlarged posterior view of the infrafacial approach. The rostral border of this approach is the inferior intrapontine segment of the facial nerve forming the lower edge of the facial colliculus and corresponding to the level of a transverse line crossing the upper edges of the lateral recesses. The caudal border of the infrafacial approach, which is the site of horizontal attachment of the tela choroidea along the lower margin of the lateral recess, is positioned at the same transverse level as the upper margin of the hypoglossal triangle. The lateral edge of the ipsilateral medial longitudinal fasciculus forms the medial border and the facial nucleus and nucleus ambiguus are positioned below the surface of the floor at the lateral border of the infrafacial approach. The facial nucleus and nucleus ambiguus are found deep and just lateral to the most medial point of the attachment of the tela along the lower edge of the lateral recess (blue star). The facial nucleus is located at the level of the pontomedullary junction. Amb., ambiguus; Attach., attachment; Cer., cerebellar; CN, cranial nerve; Coch., cochlear; Coe., coeruleus; Coll., colliculus; Cort., cortico; CTT, central tegmental tract; Cun., cuneate; Dors., dorsal; Fac., facial; Flocc., flocculus; Fren., frenulum; Hypo., hypoglossal; Inf., inferior; Intrapon., intrapontine; Junct., junction; Lat., lateral; Lemn., lemniscus; Limit., limitans; Med., medial, median; MLF, medial longitudinal fasciculus; Nucl., nucleus; Ped., peduncle; Pon., pontine; Post., postrema; Rec., recess; Seg., segment; Spin., spinal; Sulc., sulcus; Sup., superior; Tent., tentorium; TMT, trigeminal mesencephalic tract; Tr., tract; Triang., triangle; TST, trigeminal spinal tract; Tub., tubercle; Vent., ventral; Vest., vestibular. (Images courtesy of AL Rhoton, Jr.)

圖5。A，左前外側觀。橄欖前溝位於橄欖和金字塔之間。橄欖口側凹陷，橄欖上窩，就在麵神經和前庭耳蝸神經與腦幹交界處的下方。舌咽神經、迷走神經和副神經出髓質，在橄欖後溝的背側，橄欖後溝位於橄欖和小腦下梗之間。舌下細根沿橄欖前溝出髓質。B，髓質，後視圖。岐核位於迷走神經三角的腹外側，三叉神經脊髓束的腹內側，楔形結節的腹側，橄欖的背側，麵核的尾側。舌咽神經、迷走神經和副神經的髓內段出岐核後向外側移動，在三叉神經脊髓束腹側，沿橄欖溝後出髓質。C, 3個背側髓質進入區分別位於中線obex以下的後正中溝、薄肌與楔形束之間的後中間溝和楔形束腹緣的後外側溝。 Amb., ambiguus; Cer., cerebellar; Hypo., hypoglossal; Inf., inferior; Inter., intermediate; Med., median; Nucl., nucleus; Ped., peduncle; Post., posterior; Posterolat., posterolateral; Sulc., sulcus; Triang., triangle; TST, trigeminal spinal tract; Tub., tubercle. (Images courtesy of AL Rhoton, Jr.)