CNIM - ABRET Practice Exam Questions With correct answers

Cavities inside the skull Anterior/middle/posterior fossa Cranial bones Frontal, occipital, sphenoid, ethmoid (unpaired). Parietal & temporal (paired). Mental protuberance chin bone MCA supply of the cerebral cortex Hand + face/mouth/auditory Cranial nerves -12 pairs (Mixed fibers: sensory/motor/both). -Emerge @ irregular intervals from the brain. -Nuclei displacement: Motor = medial Sensory = lateral Meckle's Cave Depression in the medial middle fossa where CN V ganglion sits Low frequency sounds @ apex of cochlea Area of spine w/ small pedicles, long spinous process, large inter-vertebral foramen Thoracic Neuroforamen Opening w/in the spinal canal for nerve roots to enter the SC Firm outer layer of the disc Annulus fibrosis Syrinx Fluid-filled cavity @ center of the SC Spinal cord ends @ the level btwn: L1-L2 vertebrae (Conus Medullaris) Blood supply to the SC consists of: 1 ASA for both MEP tracts Hydrostatic pressure Depends on body position Structural functional anatomy may be altered by: Previous lesions, current, plasticity, pressure Glia cell Comes from the Greek word "glue" Large diameter nerve fiber (vs. small diameter) -Recruited 1st w/ INC'd stim intensity -Higher conduction velocity -More vulnerable to hypoxia & pressure Δ's Synaptic transmission, and/or Δ's in thalamocortical projections, produce Cortical potentials Peripheral nerve sensitivity Least sensitive to injury (more sensitive = SC grey/white mater, cortical grey matter) Cavernous angiomas Multi-lobulated lesions containing hemorrhage Geriatric population: prevalence of temporal bone hyperostosis 10-15% Presbycusis High freq hearing loss; gradually occurs in older individuals Most commonly injured CN Facial nerve (VII) Burst fracture -Break in the vertebra -Failure of anterior & middle vertebral columns -Caused by violent compressive event (fall, MVA) Excessive neck flexion in sitting position Quadraparesis (due to ischemia in upper T-spine) Lhermittes Sign Shocking sensation that occurs throughout the body during neck flexion Central Cord Syndrome (CCS) -Sacral sparing -Loss of sensory/motor fx @ level of injury -Disruption of grey matter