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Radiology Exam 1
Chapter 2
Question | Answer |
---|---|
What is the most common problem in viewing plain films of the skull? | Differentiating between cranial sutures from vascular grooves and fractures |
What are the four common cranial sutures? | Coronal, Sagittal, Squamous, Lambdoidal |
What do cranial sutures look like on plain films? | Symmetric, "wiggly lines" that have white sclerotic edges |
Why are the edges of cranial sutures white? | Over ossification of the joint spaces |
What do vascular grooves look like on plain films? | They are linear markings that extend posteriorly and superiorly; they are irregular and do not have sclerotic edges |
What view are vascular grooves usually seen on? | Lateral |
What does a fracture look like on a plain film radiograph? | A dark, radiolucent line that has sharp edges and tends to be very straight |
T or F; You can tell whether a fracture is new or old by the presence of sclerotic borders. | True; sclerotic borders indicate bone healing, therefore, a new acute fx will NOT have sclerotic edges |
T or F: Severe brain in injury can occur without fracture. | True |
What type of imaging is recommended for head trauma? | CT |
T or F: Skull fractures without loss of consciousness are common | False; It is very rare to see skull fractures without loss of consciousness |
What is the term for the appearance of increased density in the frontal region on plain film radiographs? | Hyperostosis frontalis interna |
Is hyperostosis frontalis interna a malignant or benign condition? | It is a benign finding common in females |
If pineal calcification is seen on plain film XRay, is it considered benign or malignant? | Benign |
What is the term for calcification of the lateral ventricles of the brain called? | Choroid plexus calcifications |
Are choroid plexus calcifications benign or malignant findings? | Benign |
Name three normal variants (benign findings) found on plain film X-Ray. | Hyperostosis frontalis interna; Pineal calcifications; Choroid plexus calcifications |
T or F: Large, asymmetric or unilateral calcifications found on plain film X-Ray are possible AVMs or neoplasms | True; send these patients for a CT and possibly an MRI |
What might an asymmetrical round or ill defined "hole" on a plain film X-Ray indicate? | Possible metastatic disease |
The early stage of this disease is a lytic or bone destroying phase... | Paget's Disease |
What happens in the second stage of Paget's disease? | Bone overgrowth and increased density causing a "cotton wool" appearance |
Where are the effects of Paget's disease mostly seen? | The skull and the pelvis |
Increased focal densities that are whiter than normal usually indicate what? | Calcifications |
Three types of relatively small, secondary calcifications seen on plain view X-Ray are: | Tuberous sclerosis, Toxoplasmosis, and Granulomatous disease |
Three types of suspicious calcifications are: | AVM, gliomas, meningiomas |
T or F: Large, irregular, and unilateral calcifications are called "secondary calcifications". | False: Large, irregular, unilateral calcifications are "suspicious". |
When dealing with a head trauma patient, the first thing that needs to be done before imaging is... | Clinical examination to assess risk! |
T or F: If a patient presents as asymptomatic or have only dizziness, mild HA, scalp laceration, or hematoma, they are considered at LOW RISK. | True |
T or F: For a low risk patient a skull X-Ray is usually adequate. | True |
List some clinical symptoms of someone with head trauma who is Moderate Risk. | Change in level of consciousness, progressive or severe HA, post-traumatic seizures, persisting vomiting, hemotympanun, skull fracture, rhinorrhea, otorrhea, or if the pt is less than two years old |
What is the term for "Raccoon eyes" caused by head trauma and what is it indicative of? | Hemotympanum- indicates Basilar Skull Fx |
Why are otorrhea and rhinorrea concerns in head trauma? | It may be CSF leakage |
What type of imaging should be ordered for a moderate-risk head trauma patient? | Plain film and CT (possible MRI) |
List some clinical findings of a High Risk head trauma patient. | Focal neurologic findings, Glasgow Coma score of 8 or less, Definite skull penetration, Postictal state, Decreased or depressed levels of consciousness |
T or F: The higher a Glasgow Coma score, the worse the neurological deficit is. | False; a lower score indicates a worse neurological deficit |
A high-risk head trauma patient should have what kind of imaging done? | Plain Film and CT... an MRI should be ordered if the patient is stable |
On a plain film radiograph of a skull, what type of fracture is classified as lucent lines (darker than surrounding bone) through the cranial vault? | linear fracture |
on a plain film radiograph of a skull what type of fracture has stellate or semicircular lines? | Depressed skull fractures |
What is the best choice to evaluate any skull fracture for proper evaluation for direct brain injury? | CT with Bone Window |
What would be the best choice to identify subdural or epidural hematomas? | CT with Bone Window |
What Glasgow Coma score correlates with mild brain injury? Moderate? Severe? | Mild- 13 or higher Moderate- 9-12 Severe- 8 or less |
What is the highest possible score of the Glasgow Coma Scoring system? | 15- Best Eye Response (4); Best Verbal Response (5); Best Motor Response (6) |
What three categories are assessed with the Glasgow Coma Score? | Eye response; Verbal response, and Motor response |
T or F: Due to the computed enhancement of CT, actual absorption of a specific tissue can be measured. | True; this is VERY important to determine blood or fluid from solid masses in tissue |
What is the name for units of CT absorption? | Hounsfield units |
How many hounsfield units is water? air? average bone? | Water- 0 Bone- +1000 Air- -1000 |
T or F: Using Hounsfield measurements, we are able to differentiate between tissue masses, and cysts (fluid masses) on CT. | True |
T or F: X-Rays are two dimensional displays of two dimensional information. | False, X-Rays are 2D images of 3D information |
T or F: CT scans are two dimensional displays of two dimensional information | True- therefore structures seen on CT images appear where they really are in space |
T or F: Using Hounsfield measurements, we are able to differentiate between tissue masses, and cysts (fluid masses) on CT. | True |
T or F: X-Rays are two dimensional displays of two dimensional information. | False, X-Rays are 2D images of 3D information |
T or F: CT scans are two dimensional displays of two dimensional information | True- therefore structures seen on CT images appear where they really are in space |
What are some things that you must look for on every slice of a CT scan? | Increased or decreased focal densities, asymmetric gyral patterns, ventricle size, fluid sinuses, swelling of soft tissue covering skull (trauma), fractures |
What might a decreased focal density on a CT scan indicate? | Stroke, edema, tumor, surgery, or radiation |
What might an increased focal density on a noncontrast CT scan indicate? | hemorrhage, calcium, metal |
What might an increased focal density on a contrast/enhanced CT scan indicate? | hemorrhage, calcium, metal, tumor, acute stroke, aneurysm, AVM |
What is the purpose of IV and IA contrast agents? | To identify structures of different densities so that pathology can be easily identified. |
What does LOCA stand for? | low osmolar contrast agent |
What does HOCA stand for? | high osmolar contrast agent |
T or F: LOCA has less risk associated with it. | True- because of low iodine content |
T or F: LOCA is more expensive than HOCA. | True |
What patients cannot have HOCA? | Patients with iodine or shellfish allergies. HOCA can send these people into anaphylactic shock. |
What two factors must be evaluated when ordering contrast studies? | The patients age (ppl over 50 have higher prevalence of decreased renal function) and Renal function (people with renal impairment will have difficulty clearing contrast) |
Prior to performing contrast imaging, what two levels indicative of renal function should be checked in patients older than 50 or with a history of renal disease | BUN and creatinine |
How would you treat a person with a persistant mild allergic reaction to CT contrast? | IM Benadryl (50mg) |
How would you treat a person with a severe CT contrast reaction? | IV atropine (.5-1.0 mg) |
T or F: A reaction in which a person experiences vasovagal syncope and has difficulty or impaired breathing is considered a mild reaction. | False, this is a severe reaction. A mild reaction only includes slight nausea, hives, and a metallic taste in the mouth. |
When evaluating an intracranial hemorrhage on CT, what does an acute bleed look like? | Increased focal density (whiter than normal) |
T or F: Seeing an increased focal density on a CT scan is a contraindication to anticoagulation tx. | True- these focal densities could indicate an active bleed. |
T or F: Hemorrhage of the cranial ventricles is usually the result of trauma. | True |
Name some causes of Intraparenchmal/intracerebral hemorrhages. | Ruptured aneurysm; Trauma; Stroke; Tumor; Common complication of HTN |
T or F: A large hemorrhage involving the brainstem has a good prognosis for rehabilitation. | False; this type of hemorrhage is very grave |
Which hematoma (epidural or subdural) is seen as a crescent shaped abnormality between the skull and brain that never crosses the midline? | Subdural |
A white appearance of blood on a brain CT indicates an active, sub-acute, or old bleed? | Acute- new |
Would an old hematoma be light or dark on a CT scan? | Dark |
What type of hematoma shows up as a lenticular shape on a CT? | Epidural |
What type of hematoma is commonly associated with temporal Fxs? | Epidural |
Which type of intracranial hemorrhage is associated with a "Texaco Star" pattern? | Subarachnoid hemorrhage |
T or F: Since a subarachnoid hemorrhage is a hemorrhage into the ventricles, the only time that you can visualize it on CT is during the acute stage when the blood is denser than the CSF. | True |
What is it called when there is air in the cranial vault? | Pneumocephalus |
What does air look like on a CT? | Black densities |
What causes pneumocephalus? | Trauma |
What is Hydrocephalus? | Dilation of the ventricles |
What is the most commonly obstructed ventricle to cause hydrocephalus? | the 4th ventricle |
Even though poorly ischemic strokes do not show up until about 12 hours later, you should still order a CT without contrast immediately. Why? | To rule out hemorrhage so that you can safely begin anticoagulant tx. |
When you have a stroke w/o hemorrhage,how will ischemic stroke areas show up on a CT without contrast? | Decreased focal densities (dark densities) |
Why do you want to use contrast with a 24 hour post ischemic stroke CT? | to see edema as dark areas and to enhance the edges of the effected area |
Hydrocephalus is obstructive or non-obstructive? | Non-obstructive |
For tumors, would you order Ct with or without contrast? | Both |
Why would you order a CT with contrast for a tumor? | contrast shows increase in densities and outlines the vascular portion |
Why would you order a noncontrast CT for a tumor? | looks for calcifications, focal areas of decreased densities, asymetric gyral patterns, shift |
Which Sinuses are typically imaged? | Frontal, Sphenoid, Maxillary, ethmoid |
Which method is best for frontal and ethmoid sinuses? | Frontal Skull film |
Which sinus is the Walter's used commonly for? | Maxillary |
Which sinus is commonly imaged with the mouth open? | sphenoid |
Which view is best for seeing all on a sphenoid sinus. | Lateral |
Which sinus is sinusitis most commonly seen in? | Maxillary |
When imaging sinuses, what levels are we looking for? | air/fluid levels |
Which sinus is hypoplasia often seen? | Frontal sinus |
What does AVM stand for | ArterioVenous Malformation |
What are the two most common benign calcification findings? | Pineal and bilateral choroid plexus (can be singular or matched) |