Structure of the Circle of Willis Diagram

Structure of the Circle of Willis Diagram

The circle of Willis is an anastomotic arterial ring at brain base: anterior cerebral (from internal carotid), anterior communicating, internal carotid, posterior communicating (from posterior cerebral), posterior cerebral (from basilar).…
Tooth

Tooth

Tooth consists of crown visible enamel hardest substance covering dentin pulp chamber nerves vessels, neck gum junction, root cementum periodontal ligament anchoring alveolar bone, dentin tubules sensitive, pulp vital reactive…
Diagram of the Descent of the Testis Embryology Diagram

Descent of the Testis Embryology Diagram

Descent of the testis embryologically begins near kidneys at 7-8 weeks, guided by gubernaculum through inguinal canal (transabdominal phase via genitofemoral nerve), then inguinoscrotal phase (hormone-driven, testosterone/insulin-like factor 3) into…
Muscular Triangle of the Neck Diagram

Muscular Triangle of the Neck Diagram

The muscular triangle of the neck is bounded by midline, anterior digastric belly, and superior omohyoid belly, containing infrahyoid muscles (sternohyoid, sternothyroid, thyrohyoid), thyroid gland, trachea, esophagus, and common carotid…
Muscular Attachments to the Mandible Body Ramus Diagram

Muscular Attachments to the Mandible Body Ramus Diagram

Muscular attachments to mandible: body (geniohyoid/genioglossus anterior, mylohyoid lateral, digastric anterior belly), ramus (masseter lateral, medial pterygoid medial, temporalis coronoid). They enable mastication, speech, swallowing.
Anatomical Position and Relations of Pituitary Gland Diagram

Anatomical Position and Relations of Pituitary Gland Diagram

The pituitary gland sits in sella turcica, attached to hypothalamus by infundibulum, surrounded by cavernous sinuses laterally, optic chiasm superiorly, sphenoid sinus inferiorly. Relations affect surgical/transsphenoidal approaches and compression symptoms.
Regional Blood Supply to the Cerebrum Diagram

Regional Blood Supply to the Cerebrum Diagram

Regional blood supply to the cerebrum divides into anterior (anterior cerebral to medial surface), middle (middle cerebral to lateral surface, insula, basal ganglia), and posterior (posterior cerebral to occipital, inferior…
The Submandibular Ganglion and Branches Diagram

The Submandibular Ganglion and Branches Diagram

The submandibular ganglion hangs from lingual nerve, receives preganglionic parasympathetics from chorda tympani (facial), postganglionic fibers supply submandibular/sublingual glands for salivation. Sensory fibers pass through without synapse.
ASIA scale 571 Diagram

ASIA scale 57 Diagram

ASIA scale assesses spinal cord injury impairment: A complete (no sensory/motor below level), B sensory incomplete, C motor incomplete with >50% key muscles
Neurulation

Neurulation

Neurulation forms the neural tube precursor to CNS as notochord induces overlying ectoderm to thicken into plate, then elevate neural folds that fuse dorsally starting mid-region progressing cranially and caudally,…
Mastoid Fossa Overview Diagram

Mastoid Fossa Overview Diagram

The mastoid fossa (antrum) is the largest mastoid air cell, opening into middle ear via aditus ad antrum, lined by mucosa continuous with tympanic cavity. It provides space for middle…
Zygomatic Nerve Course Branches Diagram

Zygomatic Nerve Course Branches Diagram

The zygomatic nerve (V2 branch) enters orbit via inferior orbital fissure, gives zygomaticotemporal (skin over temple) and zygomaticofacial (cheek) branches, and communicates with lacrimal nerve for parasympathetics.
Radial Nerve Palsy Wristdrop Diagram

Radial Nerve Palsy Wristdrop Diagram

Radial nerve palsy causes wrist drop (loss of extensors), sensory loss dorsum hand/thumb-index-middle. Common from humeral shaft fracture (spiral groove) or Saturday night compression.