Pons in latin, refers to a “bridge”. Pons varolli is a part of brain-stem, that links thalamus with medulla oblongata. The cross-section of pons is similar to the midbrain as described earlier but few things must be kept in mind: The orientation of lemnisci in midbrain is more or less…
Tag: Anatomy
PGMEE, MRCS, USMLE, MBBS, MD/MS 
How to Draw Midbrain Cross-section ?
The cross-section of midbrain can be compared to the “upside down striped face of a red-eyed demon“. Using this analogy of a demon face, lets assign the structures found on the cross-section of midbrain: Ear = Crus cerebri Medial – frontopontine fibers Middle – corticonuclear and corticospinal tract Lateral –…
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CSF Circulation Made Simple
Cerebrospinal Fluid (CSF) Production and Absorption CSF is produced by the choroid plexus that lines the ventricles. Choroid plexus = Infoldings of blood vessels of piamater + Modified ciliated ependymal cells Tight junctions of the choroid plexus cells form Blood-CSF barrier. CSF is reabsorbed by arachnoid granulations to enter dural…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Thalamic Connections Mnemonic
Structure of Thalamus A vertical “Y” shaped white mater – internal medullary lamina divides thalamus into: In anatomical position: Pulvinar = Posterior end or posterior pole of thalamus Thalamic Connections Picture mnemonic Remember the schematic diagram drawn below showing important parts of thalamus in an anticlockwise fashion: Now, we assign…
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Germ Layer Derivatives – Mnemonics
Principle of Germ Layer Segmentation Ectoderm gives further rise to neuroectoderm and neural crest cells. Endoderm remains intact. Mesoderm gives further rise to paraxial mesoderm (somitomeres and 35 pairs of somites), intermediate mesoderm, and lateral mesoderm: General Rule for Germ Layer Derivatives Ectodermal derivatives: 1. Everything that makes you attractive: Skin, hair,…
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Medial Medullary (Dejerine’s) Syndrome : Anatomical basis mnemonic
As already discussed in the previous section about Lateral Medullary (Wallenberg) Syndrome: 6 “S” pass/lie on the Side (latetral) of Medulla Except the anteromedian part supplied by vertebral artery, rest of the medulla is supplied by PICA Let us now review the relevant anatomy and physiology of the medial portion…
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Anatomical basis of Wallenberg (Lateral Medullary) Syndrome : Mnemonic
Before proceeding into the disease itself, let’s review – relevant anatomy of the medulla with a simple mnemonic. The Side (lateral) part of Medulla contains 6 “S“ 1. Spinocerebellar tract Posterior spinocerebellar tract: Ascends and enters to ipsilateral cerebellum via ipsilateral inferior cerebellar peduncle Anterior spinocerebellar tract: Ascends and enters…
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Surgical Anatomy of Stomach
GASTROESOPHAGEAL JUNCTION (CARDIA) It is the junction between esophagus and cardia of stomach Histologically: Mucosal transition from squamous to columnar epithelium Functionally: High pressure zone (Lower esophageal sphincter or LES) – Normally, LES is intraperitoneal, >2 cm long, and has a resting pressure >6 mmHg; not an anatomical sphincter but a…