Question | Answer |
Neurons have 3 parts. what are they? | axon, cell body and dendrites |
Central Nervous System is composed of? | brain and spinal cord |
What is a dendrite? | process that conducts impulses toward the neuron cell body |
What is an axon? | process leading away from the cell body |
Multipolar motoneruon. what are they? | neurons that conduct impulses from spinal cord to muscle tissue |
What does the mulitpolar dendrite look like? | it has one axon and several dendrites |
What two parts of the neruon make up gray matter? | dendrites and cell bodies |
what part of the neuron makes up the white matter? | axons |
Where does the solid spinal cord terminate? | lower border of L1, tapered area called conus medullaris |
What is the conus medullaris? | the distal tapered ending of the spinal crd at the lower level of L1 |
what is a common lumbar puncture site for spinal tap, contrast injection, etc? | between the spines of L3 and l4 |
What is the name of the membranes protecting the brain and spinal cord? | Meninges |
Name the three layers from outer to inner of the meninges? | dura mater the outermost, arachnoid connecting the outer and inner , pia mater is the innermost layer |
What are the three potential spaces to each of the meninges layers | epidural, subdural, subarachnoid. |
Where is the epidural space of the brain? | between the dura mater and inner table of the skull |
What is the subdural space fo the brain? | between the duramater and arachnoid space |
Where is the suarachnoid space? | between the arachnoid and the pia mater |
What are the three divisions of the brain? | forebrain, midbrain, hindbrain |
What three parts make up the brain stem? | midbrain, pons and medulla oblongata |
The forebrain is comprised of ? | cerebrum, thalamus, and hypothalmus |
The hindbrain is comprised of ? | pons, medulla, and cerebellum |
the midbrain is coprised of ? | the midbrain |
How many lobes does the cerebrum have? Name them. | 5 lobes, Frontal, Parietal, Temporal, occipital, and insula (or central) |
What separates the cerebrum into right and left hemisphere? | longitudinal fissure |
What is a gyrus? | the raised convuluted area |
Which two gyri can be identified on CR sectional radiographs? | Anterior Central gyrus , and Posterior central gyrus |
What is a sulcus? | shallow groove |
What sulcus separates the parietal and frontal lobes? | central sulcus |
What is a fissure? | a deeper groove. |
How many cavities in the ventricles? Name them. | four. Rt and let lateral ventricles, third ventricle, and the fourth ventricle |
Where is Cerebral Spinal fluid formed? | lateral ventricles in specialized capillary beds called choroid plexuses |
What amount of CSF is present within and around the CNS. | 140ml |
How much CSF is produced daily? | 500ml |
Name the 4 parts of the lateral ventricle | BODY, ANTERIOR(FRONTAL), pOSTERIOR (OCCIPITAL), INFERIOR (TEMPORAL) |
The interventricular foramen connect which ventricles? | lateral and third ventricles |
What two anatomic parts is connected with the cerebral aqueduct | third and fourth ventricles |
What is the lateral recess? | a lateral extension on either side of the fourth ventricles |
What is the cerebral aqueduct? | passage that connects third and fourth ventricles |
What is the interventricular foramina? | connect the body of each lateral ventricle to the third ventricle |
What is hydrocephalus? | excessive accumulation of CSF within the ventricles |
What is a cistern? | larger areas withing the subarachnoid space |
What is the cistern cerebellomedullaris? | located inferiorly tothe fourth ventricle and the cerebellum. it is the largest cistern |
Where is a cisternal puncture normally performed? | c1 and occipital bone. this is the secondary puncture site for anesthesia into the subarachnoid space |
Where is the cisterna pontis located? | inferior and anterior to the pons |
Where is the Thalamus located? | just above the midbrain and under the corpus callosum. |
What is the function of the Thalamus? | an interpretation center for sensory impulses for pain, temperature and touch, emotions, memory |
What makes up the diencephalon? | thalamus and hypothalamus |
the hypothalamus forms the floor and lower walls of the third ventricle. true or false | true |
the thalamus forms the the walls of the third ventricles. true or false | true |
Name three significant structures associated with the hypothalamus. | infundibulum, posterior pituitary gland, and optic chiasma |
What is th infundibulum? | conical process projecting downward and ending in the posterior lobe of the pituitary gland |
the infundibulum and the posterior pituitary make up what? | neurohypophysis |
The optic chiasma is located superior to the pituitary gland and anterior to the third ventricle. true or false | true |
The function of the hypothalamus is? | to control homeostais via the endocrine system |
What is the midbrain? | short constricted area conecting the forebrain to the hindbrain |
what makes up the hindbrain? | cerebellum, pons, and medulla |
what makes up the brain stem? | midbrain, pons and medulla |
what is the function of the pineal gland? | endorcrine gland secretes hormones that aid in regulating secretory activities |
what is another name for the pituitary gland? | hypophysis |
Where is the pituitary gland located? | in and proctected by the sella turcica in the sphenoid bone and attached to the hypothalamus by the infundibulum |
what unites the right and left hemishpere of the cerebellum? | vermis |
what are the advantages of volume scanning over single slice scanning? | multiplanar reconstruction, shorter scan times, and artifacts reduced |
What is multiplanar reconstruction (MPR)? | volume scanning that allows reconstruction of patient data into alternative planes |
What is bolume ct scanners | continuous rotation of the x ray tube via slip rings |
what are the advantages of the multislice ct scanner over single or volume ct scanners? | shorter acquistion time, decreased amount of contrast media, improved spatial resolution, improved image quality. |
What are the disadvantages fo the multislice over single and volume ct scanners? | cost. |
What are the three major components of the CT system? | gantry, computer and operator console |
The gantry is made up of ? | x ray tube, detector array and collimnators |
the central opening in the gantry is called? | aperture |
what factors are included in each protocol? | kvp, ma, pitch, field of view , slice thickness, table indexing, reconstruction algorithms, and display windows |
What is volume elements or voxels? | three dimensional tissue |
The depth of a voxel is determined by? | slice thickness |
What is the baseline for CT numbers? | water = 0 |
What is window width ? | the range of CT numbers that are displayed as shades of gray , controls displayed image contrast |
What is Window level? | controls image brightness or determines the CT number that will be the center of the WW. determined by the tissue density |
What is pitch | a ratio reflecting the relationship between table speed and slice thickness. determines amount of anatomy covered in a particular scan |
what is the formula for pitch? | couch movement(mm/sec) per 360 rotation of tube/collimation |
what pitch indicates that the table speed and slice thickness are equal. | 1:1 pitch |
What is a scanogram? | preliminary scan, scout ot topogram |
How are axial scans viewed? | as though the viewer were focing the patient and looking at the scan from the foot end of the patient |
What is the relationsip of patient dose to pitch? | patient dose is inversely proportional to the pitch. lower pitch = higher dose, thinner slice = higher dose |
For a head CT the primary beam is alighned? | parallel to a line passing from the nasion to the skull |
The head CT usually performed with two window settings why? | one to allow optimal visualization of the brain with lower contrast, the other for bony detail with higher contrast |
What is subdural hemotoma? | collection of blood under the dura mater, caused by trauma to the skull |
what is hydrocephalus? | blockage to drainage of CSF from ventricles causing enlargement of ventricls |
what are two types of positive contrast agents used to opacify the gastrointestinal tract? | barium sulfate suspensions and non ionic water-soluble solutions |