Radiology and internal Flashcards
Uses of x-ray
- Orthopedic (bone and joints) evaluation
- Chest or abdomen examination
- Dental examination
- Mammography
- Verification of correct placement of surgical markers prior to invasive procedures.
- Spot film or static recording during fluoroscopy.
Advantages and disadvantages of x-ray
Advantages
* Good bone assessment.
* Widely available
* Quick and cheap imaging modality
Disadvantages
* Uses ionizing radiation can cause cells mutation and cancer
* Not suitable for pregnant woman or soft tissues evaluation
Different types of transducers according to organ are?
Examining deep structures:
As abdominal organs»»>Using convex transducer
Obstetrical and gynaecological exam»» using Transvaginal probe or/and convex probe
Echocardiography»»sector probe
Transcranial US»»>sector probe
Examining superficial structures:»»Using linear probe
- e.g Small parts (Neck, breast, scrotal)
- Vascular Doppler
- Musculoskelatal ultrasound
Advantage and disadvantage of Ultrasound
Advantages of US over other imaging modalities
Lack of ionizing radiation, a particular advantage in pregnancy and pediatrics
Low cost
Wide availability
Portability of equipment.
Disadvantages and limitations of US
US is highly operator dependent: US relies on the operator toproduce and interpret images at
the time of examination.
US cannot penetrate gas or bone.
Bowel gas may obscure structures deep in the abdomen, such asthe pancreas.
Common indications of CT
- Emergencies
-Head trauma (Acute bleeding, skull fractures)
-Stroke (differentiate Ischemic from hemorrhagic stroke)
-Poly trauma (Solid organ injury and acute hemorrhage) - Bone fracture
- Complex intra-abdominal conditions:
solid organ focal lesions ( hepatic , renal, spleen) , intestinal obstruction, inflammatory conditions, biliary obstruction, acute vascular conditions and different abdominal masses.
4.Chest:
pneumonia (the standard imaging modality in COVID 19),lung masses, mediastinal LNs, trauma, pneumothorax, hemothorax.
Contraindications of CT
-Absolute : Early pregnancy
-Relative: Children. Renal impairment, allergy tp contrast, pheochromocytoma patient since intra-venous contrast may induce hypertensive crisis
.
MRI principle
The MR scanner used strong magnetic fields, magnetic field gradient and radio waves to generate images of the organs.
MRI is based on the magnetization properties of atomic nuclei using a powerful, uniform, external magnetic field.
Used in soft tissues imaging.
Advantages and disadvantages of MRI
Advantages:
-No x-ray or ionizing radiations, non invasive so its highly accepted.
-MRI produces images in multiple planes with equivalent resolution without moving the patient.
-MRI contrast agents are very well tolerated and are much less likely than x-ray and CT
contrast agents to cause allergic reactions or alter kidney function
Disadvantages:
-Claustrophobia
-Loud noise
-Keeping still for long time
-Expensive and not widely available
Contraindications of MRI
1- People with implants, particularly those containing iron, —pacemakers, vagus nerve stimulators, implantable cardioverter-defibrillators, loop recorders, insulin pumps, cochlear implants, deep brain stimulators, and capsules from capsule endoscopy should not enter an MRI machine.
2- Pregnancy: Not in the 1st trimester
3- Contrast agents—patients with severe renal failure who require dialysis may risk a rare but serious illness called nephrogenic systemic fibrosis that may be linked to the use of certain gadolinium-containing agents, such as gadodiamide
Goals of preoperative assessment
- Assess the fitness for anesthesia.
- Optimizing patient physical condition for anesthesia and surgery.
- Arrange further investigations, consultations and treatments for patients not yet
optimized - Allay fear and anxiety.
- Establishment of preoperative fasting.
- Premedication.
- Provide appropriate information to the patient and obtain consent.
History questions?
- History of present illness and reason for surgery
- Past medical history
- Medical conditions (acute and chronic)
- Previous hospitalization and surgeries
- History of any past problem with anesthesia
- Allergies
- Substance use: alcohol, tobacco, street drugs
- Family history: Hereditary diseases.
- Drug history
Respiratory examination
- Presence of cyanosis (peripheral or central).
- Presence of cough
- Presence of tachypnoea
- Tracheal shift
- Auscultation of all the lung fields
General examination
- Nutritional state
- Fluid balance.
- Condition of skin and mucus m.(anaemia –perfusion-jaundice )
- Temperature
Airway examination
- Teeth exam (dentures, loose teeth, protruding upper incisors)
- Prediction of difficult airway (for ventilation or endotracheal
intubation)
Cardiovascular examination
- Presence of dyspnea, fatigue, chest pain.
- Peripheral pulse (rate, rhythm, volume).
- Neck veins
- Carotid bruits
- Heart sounds
- Lower Limb edema
