We have already discussed earlier on the intracranial course of Internal Carotid Artery (ICA) and Circle of Willis formation with the help of a simple mnemonic. General Concepts of Blood Supply of Brain and Spinal Cord 1. Spinal cord, Hind-brain and Mid-brain: Veterbro-basilar system 2. Forebrain: Circle of willis which…
Author: Epomedicine
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Brodmann Areas and Lesions
Frontal Lobe Area 4 (Precentral gyrus): Primary motor cortex (gigantopyramidal – only area that contains giant pyramidal cells of Betz) Lesion: Contralateral spastic paralysis (UMNL) Area 6 (Superior frontal gyrus; agranular frontal): Premotor cortex and Supplementary motor cortex (Motor planning) Lesion: Apraxia (Unable to perform movements in correct sequence) Area…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Internal Capsule Simplified
Internal Capsule is a “boomerang” shaped (on horizontal section) and “funnel” shaped, i.e. tapering from superior to inferior (on sagittal section) white matter structure sandwiched between: Medially: Head of Caudate nucleus and Thalamus Laterally: Lenticular nucleus (Globus pallidus and Putamen) Parts of Internal Capsule 1. Anterior limb: Carries fibers to…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Visual Pathway : Supplement Knowledge
Everyone must be aware of the normal visual pathway and their defects. Here, I’ve tried to enlist the topics related to the visual pathway that are “nice to know” but you may have missed it or failed to understand properly. Below is the basic visual pathway: Wilbrand’s knee Anterior…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Retinal Layers Simplified
The ten layers of retina – this microscopic anatomy is frequently asked in examinations and also important from the physiological viewpoint. There are plenty of mnemonics around the web, but we will proceed in a different approach to remember the 10 retinal layers easily. A. Retina is 3 neuron system…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Basal Ganglia Pathways Simplified
The combination of excitatory and inhibitory signals in the basal ganglia circuit is pretty confusing. Let’s break the circuit and make them easy to understand. There are 2 pathways in Basal ganglia circuit: Excitatory pathway Inhibitory pathway Let’s declare 2 things first: Dopaminergic nigrostriatal projection increases motor activity. Cholinergic striatal…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Vertebrobasilar Arterial System and Syndromes Simplified
Vertebral Artery I use the analogy of hand to remember the vertebral artery and it’s branches: Origin: Branch of subclavian arteries Course: Ascends through transverse foramina on C6 through C1 and enters posterior fossa through foramen magnum Continue up the ventral surface of medulla Converge at the ponto-medullary junction to form…
PGMEE, MRCS, USMLE, MBBS, MD/MS 
Horizontal Conjugate Gaze Pathway
Components of Pathway For both eyes to look at a side: Contralateral Frontal Eye Field (Brodmann area 8) Ipsilateral PPRF (Paramedial Pontine Reticular Formation) Ipsilateral CN VI Nucleus Contralateral Medial Longitudinal Fasciculus (MLF) Contralateral CN III Nucleus Horizontal Conjugate Gaze Pathway Lesions of Conjugate Gaze Pathway Abducens (CN VI) nerve:…