RT VIVA

What is this view?

Westpoint view

Positioning for a Westpoint View of the shoulder

• Patient is prone

• Affected shoulder placed on a sponge, elevating it 8cm

• Arm is abducted 90deg with forearm hanging over table

• IR is placed at superior part of the affected shoulder

Tube rotation: 25 deg to mid-sagittal plane and 25 deg caudal angulation

What is this view?

Striker View

How to position for a Striker view?

• Mid-coronal plane of the pt is parallel to detector

• Pt rotated 30-45 deg towards the affected side, this shows the glenohumeral head

• Affected arm is flexed and abducted anteriorly, resting the hand on the forehead while maintaining internal rotation

• 10-15 deg cephalic angulation

CP= mid-axilla at level of glenohumeral head

What does a Valpeau view show?

Shows Gleno-humeral relationship but does not require abduction of arm

Positioning for a Valpeau view

• Detector placed behind patient on table around height of sacrum

• Pt erect

• Lean them posteriorly 30 deg over the detector

• Xray tube is perpendicular to the detector, centred at the glenohumeral joint

MCU Collimation and Positioning

• Centre Point: 5cm above symph (middle of pelvic brim)

• Centre Point (KUB): level of Iliac crests or just above to include the upper poles of the kidneys to the bottom of the bladder

• Angulation: No angle, no foreshortening of the pelvic or uterine structures

• Rotation: Generally true AP position required (shown by alignment of the sacral structures with the symph)

• Collimation: Bladder, urethra and distal ureters

• Collimation (KUB): Include the Upper poles of the kidneys

Pt and Room Prep - MCU

Pt Prep

• NBM morning before

• Allergies to CM

• Everything set up before child is in the room

• Parent present- check their pregnancy, lead apron

• Reassurance and distraction techniques

• Give the child a bottle while on table for comfort

• Minimum staff

• Calm atmosphere

Room Prep

• Table flat for catheterisation

• Absorbent pads on table

• Table horizontal for procedures, absorbent pads

• CM ready

• Paediatric settings on equipment

• Catheterisation- frog position

• Urine specimen pottle, antibiotics

Pt and Room Prep - Barium Swallow and Meal

• The patient needs to be NBM* on the day. No smoking or chewing gum for 8-12 hours prior

• Explain procedure- hold barium in mouth until ready to swallow, raise hand to let us know you will swallow

• Glasses and Jewellery removed

• The fluoro table needs to be upright, with footrest and handles attached.

• Barium needs to be mixed with a cup, straw and spoon handy.

• Other consistencies of food such as a biscuit and banana need to be at hand

• *For elderly and stoke pts there is risk of choking, aspiration pneumonia. Before beginning, check if they can safely drink water before commencing

Clinical Indications for Ba Swallow

• Dysphagia

• Gastro-oesopghageal reflux (GERD)

• Sensation of food sticking

• Regurgitation of food

• Stroke

• Lap band or gastric sleeve surgery

• ?Foreign object

• ? Rupture - eg: sword swallower

Risks for MCU

• UTI and Bleeding

Clinical Indications for MCU

• Vesicoureteric reflux (VUR)

• Recurrent UTIs

• Congenital abnormalities

• Posterior urethral valves

• Unstable bladder

3 Ds for MCU

Distension – The bladder has been fully distended, enough contrast media has been introduced to show the bladder fully expanded.

Delineation- The bladder has been fully delineated, the contrast media has ensured that it is clearly distinguishable within the pelvis, even though it is a soft tissue structure. The contrast media has ensured that any abnormalities in the bladder wall will be demonstrated

Density – The contrast media has a high atomic number, it is probably iodinated CM,  it attenuates the the x-rays and allow us to clearly visualise the soft tissue structure of the bladder

Ways to reduce nephrotoxic affects of CM if the pt was suffering from renal insufficiency

• Use a low-osmolar contrast media such as Omnipaque

Radiation Protection for MCU

• Collimate only to the ROI - bladder, urethra and ureters. Kidneys if needed

• Undercouch

• Staff wear lead

• Low exposures

• Radiation lights when screening

• Suspend low exposures when radiation not in use

• Low frame rate

Key Imaging steps- MCU

Key imaging steps

1. AP control- bladder stones, spinal anomalies

2. AP- filled bladder

3. Oblique- R and L filled bladder to see vesicoureteric junction (diverticula), grade 1 VUR

4. Oblique micturating- beginning, middle, end

5. AP film to include renal areas at the end

If reflux occurs, pick up child then take a post drainage film

Radiation Protection for Ba Swallow

1- Warning lights for x-ray on

2- Fluoro rooms should not be used as corridors. Where possible porters should not be knocking on the suite door when patients arrive. Sometimes you may need to lock the suite door for both radiation protection and privacy reasons.

3- Undercouch technique with II as close as possible to patient

4- Last image hold, scroll through previous run

5- Only those directly helping with procedure in room- when helping patient be aware of high dose areas around the unit.

6- Pb gowns, thyroid shields, glasses

7- Ceiling mounted glass screens, Pb skirts around II

8- Limiting screening times and the use of magnification

9- ID and pregnancy check

CM for Swallows and Meals

Swallow: Double contrast (air from granules and dense barium)

• Fizzy Granules - Sodium Bicarbonate

• Barium in water

Meal: Double Contrast (Air from granules and dense barium

• Fizzy Granules - Sodium Bicarbonate

• Barium in water

3 Ds for Ba Swallow and Meal

• Density - CM needs to be dense enough to not be diluted by GI contents

• Delineation - CM needs to delineate the ROI – GI tract is similar densities to surrounding organs and often overlapped by other anatomic structures

• Distension – CM needs to either be dense enough to distend the anatomy or have dual CM to distend the ROI – i.e. fizzy granules during a Ba Swallow

Routine Views - Ba Swallow

Pharynx & Upper Oesophagus:

• —AP chin raised

• —Lateral (shoulders slightly off lateral)

Lower Oesophagus:

• —AP

• —RAO (Oesophagus posterior to the heart)

• —Lateral

• —Trendelenburg RAO

Why is an oblique projection ideal for Ba Swallow?

AP- Prevents superimposition of the Heart and Spine over the esophagus

Lateral- Prevents superimposition of the Shoulders over the esophagus

Why speech therapist are often involved in Video Swallows?

Speech therapists can analyse the various stages of swallow (bonus point for: Oral preparatory, Oral propulsive, Pharyngeal, Oesophageal) and prescribe treatment such as swallowing/coughing exercises (to improve muscle tone) or special diets to prevent aspiration.

Types of CM

Iodinated – positive CM. intravenous or intracavitary. Is water soluble and commonly used in Contrast CT, angiography, HSG, IVU and Intracavitary

Barium – Used in imaging of the digestive system. Not water soluble and commonly used in barium swallows, meals, follow throughs (eg SBFT) and enemas

Air – negative CM (less radio-opaque) used with Barium for enemas

CO2 – negative agent (less radio-opaque). Easily reabsorbed by the body

Aftercare for Barium

Barium Aftercare:

1. Drink plenty of fluids

2. Fiber to remove from the body

3. Stools may be white (normal)

Aftercare for Omnipaque

1.Drink plenty of fluids

VUR Scale for MCUs and how this appears on the image

1. Into a non-dilated ureter

2. Into the pelvis and calyces without dilation

3. Mild to moderate dilation of the ureter, renal pelvis and calyces with minimal blunting of the fornices

4. Moderate ureteral tortuosity and dilation of the pelvis and calyces

5. Gross dilation of the ureter, pelvis and calyces, loss of papillary impressions and ureteral tortuosity

Peripheral Angio Equipment

• DR Flat panel C-arm

• Sterile procedure equipment:

• Gloves, gowns, Towels, drapes, II covers

• Gauze, scalpel, needles, scissors, syringes, bowls, catheters, wires, sheaths

• Saline, Heparin, Lidocaine, CM, skin prep solution

• Monitoring equipment

• Blood pressure cuff, oximeter, pulse

• Oxygen

• Ultrasound machine

• Anaesthetic Equipment

Risks and complications of Angiography (peripheral and coronary)

• Swelling, bleeding, or infection at catheter insertion site

• Contrast media reactions

• Vessel dissection caused by catheter

• Thrombus/embolus formation – risk of causing stroke

• SOB/Fluid overload in patients with known CHF

• Perforation

Safe use of Contrast Media and types used

• Check the bottle is sealed, and has not been opened

• Check bottle for any damage

• Check expiry date, type (Omni 300), concentration and volume

• Types=

• Visipaque 270 (better for angiography as iso-osmolar)

• Omnipaque 300

• Safety for patient= Over 150mL used in total, saline IV used for hydration helping in elimination of CM from the body

Pt Prep for Angio procedures (peripheral or coronary)

•  Must include INR or clotting check, GFR or creatinine level check

• Previous contrast reaction or history of allergies

• Pregnancy check if female and within pregnancy age-range

• NBM 4 hours pre-procedure, but fluid intake is encouraged

• Pt bring their usual medication/provide a list of medications they take ( ask whether taking metformin, aspirin or other blood thinning medications )

• Pts asked to arrive at the Radiology dept before the scheduled appt time

• Pt asked to sign a consent form which lets them know what occurs in the procedure and that they understand the risks and complications it may cause

Contraindications for Angio procedures

• Coagulopathy-low or fast clotting time

• Uncontrolled hypertension

• Arrhythmia

• CM allergy

• Pregnancy

• High creatinine levels

4 Step Imaging Procedure for Angio

Beginning:

• 1. Seldinger technique to introduce catheter. Imaging of the guidewire and catheter to the vessels of interest

Middle:

2. CM is injected through the catheter and a series of diagnostic images are taken to assess the anatomy of the region for any abnormality

3. Once the cause for symptoms and any abnormality identified a treatment plan is discussed and agreed. Treatment goes ahead (balloon, stent insertion or drug eluting balloon)

End:

4. A final series of images are taken to see if treatment was effective i.e. return of normal blood flow

Interventional Techniques and Devices

PTCA- Angioplasty balloon, stent insertion or drug eluting stents

These are used to treat stenosis from atherosclerosis (vessel plaque) in the heart and other areas

Radiation Protection in Angio

Pt Protection

• ID, Pregnancy

• Pulsed fluoro, low screening settings, high kV-low mAs

• II in close to patient

• alarms, collimated field, programmed positions, tube underneath- scatter projected to the floor

Staff Protection

• Pb aprons, screens, glasses

• X-ray tube- under couch, limiting numbers within room, badges,

• adjusting table height to bring II in close

• MRTs leave room for full exposure runs

Post Procedure Care for Angio

• Catheter removed – compression (or angioseal or another closure device can be used)

• Patient taken to the ward.

• Bed rest- min 4 hours. Head up 30 degrees

• Nurses on the ward will carry out regular observations such as pulse and blood pressure measurements.

• There may be a small amount of bruising in the groin or wrist (arterial entry)

• Any specific Instructions (dependent on the procedure performed) given to patient from nurse (leaflet inserted in patient’s notes)

• Drink plenty of fluid (flush CM)

• If sedation given, no driving for 24 hours

Mobile CXR review for pathology

Lung fields – Equal transradiancy, fissures, apices.

Trachea – Central with slight deviation to the R around the aortic knuckle.

Hilum – The left hilum should be higher than the Right. The hila should be concave in shape and look similar, so compare the shape and density of them.

Heart, & Mediastinum- check for normal shape and size, clear edges. Cardiothoracic ratio.

Diaphragms  and Costophrenic angles – R diaphragm should be higher than the left as heart pushes L side down. Well defined acute angles

Bones and Soft Tissue - Check for rib #s and subcutaneous emphysema

Difficulties with Imaging of Mobile CXR

Difficulty with:

• ensuring the correct SID of 15cm is used,

• the angulation of the detector is perpendicular to the CR, Difficulty ensuring no rotation as the patient is obviously unwell

• that the patient is able to sit erect (may have to support the IR with sponges/pillows to keep it vertical)

• the patient may not be able to take an adequate inspiration

• needing to be as quick and efficient as possible as the referring Dr will be waiting for result so that treatment can begin

• needing to navigate around oxygen, drains or extra staff.

What is the abbreviation: MIP

Maximum Intensity Projection - a 3D imaging technique that highlights the brightest structures in a set of images

What is the abbreviation: DFOV

Display Field of View - determines how much of the scan field of view is reconstructed onto an image

What is the abbreviation: VR

Volume Rendering - VR uses thin slices to create a 3D structure that represents all depths of tissues

• This can be manipulated in the 3D plane to show pathological changes and likely relationships resulting from trauma to be easily spotted

Artefact definition

Discrepancies in the reconstructed CT image which don’t represent the true attenuation coefficients (true structure) of the object scanned

Define SOL

Space Occupying Lesion - either a tumour, abscess or haematoma

Clinical Indications for a CT Head

• ? Degenerative Change

• ? Dementia

• ? Stroke

• ? SOL

• ? Tumour

• ? Mets

• Infection or inflammatory change - abscess, encephalitis, meningitis

• Congenital conditions

• Endocrine conditions

Anatomical landmarks required for axial slices in a scout view

• Include all of brain stem and bones base of skull (base of medulla oblongata)

• Last slice should be through the vertex

• Angled to include only the bony supraorbital margin

Define: SAH

Subarachnoid Haemorrhage - blood collects beneath the arachnoid mater in the subarachnoid space (occurs near site of a skull #)

Define: SDH

Subdural Haematoma - Blood accumulates between the dura and arachnoid mater of the meninges, bleeding in the ventricles and causes a midline shift

Define: EDH

Epidural Haematoma - arterial bleeding between the dura and the skull vault (associated with skull #)

Clinical Indications for CT

Benefits

• Readily available

• Fast to perform (1 min or less)

• Highly accurate for intracranial injuries req surgical treatment

• Sensitive for calvarial and skull base #s

• Can be performed easily in patients who are intubated and being monitored due to severe injuries

Risks

• Ionising radiation - pt dose

  Insensitive to:

  • Vascular injuries

  • Diffuse axonal injury

  • Mild parenchymal contusion

Clinical Indications for MRI

Strengths

• Uses magnetic field and radiofreq pulses to produce an image

• No ionising radiation

• Sensitive to brain parenchymal and vascular injury

 

Weaknesses

• Takes longer than CT (20 mins)

• Not readily available to every ED

• Harder to monitor unstable pts in the MRI environment

• Confused pts may need gen anaesthesia (avoid movement)

• Does not demonstrate most calvarial/skull base #s

• Ferromagnetic FB (bullets, metal fragments) in the pt may move during scanning and thus represent a contraindication

• Pacemakers, some types of implants are contraindications to MRI as they malfunction and/or move in the MR environment

GCS

Glasgow Coma Scale

• 13+ Mild Brain Injury

• 9-12 Moderate brain Injury

• >8 severe brain injury