A myelogram is a radiographic procedure where contrast medium is injected into the spinal subarachnoid space to evaluate the spinal cord, nerve roots, and spinal canal for abnormalities. It is performed by a radiologist under fluoroscopy guidance and involves inserting a needle into the lumbar or cervical spine to inject contrast medium. Images are then taken under fluoroscopy and with conventional radiography in multiple positions to visualize the entire spinal canal and assess for any structural abnormalities. Patients are monitored after the procedure and advised on post-procedure care depending on the type of contrast medium used.

1. MYELOGRAM
Mohammed Althaf
Dept : of Radiology
AJ Institute of Medical Science

2. 🔑Key points:
Anatomical review
Definition
Indication & contraindication
Who does the Myelogram
Where is Myelogram done
Purpose of Myelogram
Special concern
Patient prepration
CM (type, injection process, puncture position)
Before Myelogram
Imaging technique & what you experienced
Conventional radiograph positions
Post procedure care (After Myelogram)
Benefits and risk
Result
Limitations of Myelogram

3. SPINAL CORD
RADIOGRAPHY

4. Central Nervous System
For descriptive purpose the Central Nervous
System is divided into two parts.
A) The Brain : which occupies the cranial cavity
B) The Spinal Cord : which suspended within the
vertebral canal

5. THE BRAIN

6. BRAIN:-
The brain composed of
An outer portion of Grey matter (Cortex).
An inner portion of white matter
The brain consist of
Cerebrum
Cerebellum
Brain stem
The brain stem consist of
Mid brain
Pons
Medulla oblongata

7. The cerebrum is the largest part of the
brain and is referred to as the Forebrain
The stem like portion that connects the
cerebrum - to the pons & cerebellum is
termed as the Midbrain
The cerebellum, pons & medulla oblongata
makes up the Hindbrain

8. A deep cleft called The Longitudinal
sulcus, separate the cerebrum into two
R & L hemispheres
The two cerebral two hemispheres are
connected through the structure called
Corpus Collosum

9. ☛ventricular system:-
The ventricular system of
the brain consist of four
irregular fluid filled cavities
These fluid filled cavities are
communicating with one
another through
connecting channels

10. The two upper cavities are called the lateral
ventricles (R) & (L)
Each lateral ventricle consist of
A. Body
B. Anterior, Posterior & Inferior Hornes

11. Each lateral ventricles is connected to the 3rd ventricle
by the channel called intra - ventricular foramen
The 3rd ventricle is connected to the 4th ventricle by a
channel called cerebral aqueduct
4th ventricle opens with the central canal of the
medulla oblongata

12. THE
SPINAL CORD

13. SPINAL CORD:-
The spinal cord is a slender, elongated
structure consist of
A. An inner, grey cellular substance
B. An outer, white fibrous substance
The cord extends from the brain, were it
is connected to the medulla oblongata
at the level of the foramen magnum to
approximate level of the space between
the 1st & 2nd lumbar vertebra.
The spinal cord is connected to 31 pair
of spinal nerves
These spinal nerves resembles a horse’s
tail and are referred to as the cauda
equina

14. The brain & spinal cord are enclosed in 3 continuous, protective membrane called
Meninges
The inner sheeth is called Piamatter
The middle sheeth is called Arachnoid matter
The outer sheeth is called Duramatter
The space between piamatter & arachnoid matter is called sub arachnoid space
☛Meninges:-

15. ? what is Myelogram
The term “myelos” it is a Greek word, which means marrow
(spinal cord)
A myelogram is a radiographic study combining the use of a
contrast medium is injected in to spinal sub arachnoid space
with the help of fluoroscopic condition, to evaluate the
structural details of spinal cord, conus medullaris, nerve roots,
spinal canal & abnormalities of the spinal cord
Usually completed within 30 to 60 minutes

16. ☛Indications:-
Spinal cord tumours
Cysts
Infections
Suspected spinal mass lesions caused by disease / trauma
Disc lesion
Arachnoiditis
Spinal nerve root injury
Fracture
UB & bowel disturbance
Back pain radiating to limbs
Compression of spinal cord by a herniated disc

17. ☛Contraindications:-
Blood in CSF
Increased intra cranial pressure
Decreased platelet count / (pt)’s on anticoagulant
Recent lumbar puncture (upto 7 days)
Iodine sensitivity

18. ? Who does the myelogram:-
The myelogram will be carried out
by a RADIOLOGIST.
Trained in carrying out radiology
procedures and interpreting x-ray
images. The radiologist will be
assisted by the radiographer, who is
the technician who operates the x-
ray machine while the procedure is
carried out and the CT scan
after wards

19. ?Where is myelogram done:-
A myelogram is usually carried out in a private
radiology practice or hospital radiology
department equipped with x-ray screening were
there is fluoroscopy available & a CT scanner.
Fluoroscopy equipment is were the x-ray images
can be watched on a TV screen as the procedure is
being carried out.

20. ☛Special concern:-
Pregnant women should not undergo this test because
exposure to ionising radiation may harm the foetus
Myelogram is not appropriate for individuals who have
increased intracranial pressure, infection at the site of
the needle insertion (or) multiple sclerosis.
Different types of contrast dyes either oil based (or)
water soluble may be used for this procedure oil based
dyes must be withdrawn after myelogram before the
needle is removed ; this is not necessary with water
soluble dyes which are absorbed by the body and
excreted through kidneys.

21. people with allergies to iodine (or) may
experience with allergic reaction to iodinated,
oil based contrast dyes
Certain dyes can increase the risk of seizures
in (pt)’s receiving a water soluble contrast
agent, such as Metrizamide
People who experience “Claustrauphobia” may
find it difficult to under go a CT scan, which
takes place in a narrow tunnel like structure,
in addition the CT scan may not be possible for
severely over weight individuals (over 300lbs)

22. ☛Patient prepration:-
Remove any metal objects or clothing that might interfere with the x-ray images
Injectable sedative- muscle relaxant at 1hr before the examination, to reduce
anxiety and relax the patient
Solid foods are avoided for several hrs before the exam (4hrs fasting prior to
exam)
Increase (pt) fluid intake the day a sheduled myelogram (plenty of oral fluids on
the previous day)
Informed consent from the patient
Prepration of the site of LP
Xylocaine sensitivity testing.

23. ☛Contrast Medium:-
Types:-
Oil-based
Water soluble
Air - contrast
Currently:-
Non ionic, water soluble iodine based cm
Dosage:- Generally 6-17ml
recommended by manufacturer and varies with
the medium concentration.

24. ☛Water soluble contrast media:-
ionic contrast media are contraindicated for
intrathecal injection (as they cause meningeal
irritation and may prove fatal)
Eg:- Iohexol - Omnipaque ; Iopamidol - Iopamiro

25. ☛Injection of Contrast Medium:-
Where ? In to sub arachnoid space
The radiologist looks at the spine under
fluoroscopy to find the best location to position
the needle
The skin cleaned, & apply the local anaesthetic
The needle is inserted and the contrast medium
is injected through in to the subarachnoid space
lumbar puncture
(L3 - L4)
Cervical puncture
(C1 - C2)

26. ☛Before the myelogram:-
If iodinated dye is to be used, you may be give a combined antihistamine steroid
preparation, to reduce the risk of allergic reaction.
Tell your doctor, if you are taking any medications, herbs or supplements. Take the
advice to discontinue, before test.
Tell your doctor, if you are, could be pregnant
Should be disclose, taking any medications for seizures
Do not smoke the day before the test
Do not eat or drink for 8hrs, before the test
Take the advice your bladder and bowels are empty before the test
Give an anticholinergic drug (atropin) in addition to sedative to reduce swallowing
during the procedure
To remove clothes & metallic objects ( including watch, hair clips, other jewellery)
and put on a hospital gown.

27. ☛Lumbar puncture:-

28. Puncture position
Body position for lumbar puncture
A. Prone position
B. Left lateral position with spine flexed to widen to the
inter spinous space
For low lumbar disease, administrated caudal injection
Operators palpate an indentation along the lowest portion
of the sacrum & under fluoroscopic condition
Insert a needle into the sacral hiatus
Body position for cervical punter
1. Erect position
2. Prone position with the head flexed to open the
interspinous space.

29. Iodine contrast medium
Is injected (∽2ml iohexol)
Omnipaque 180. To confirm
optimal placement in the
sacral epidural space
Not into the thecal sac
A long acting steroid
(18mg Celestone) is then
usually injected

30. ☛What you experienced :-
(pt) lies on a table with your knees drawn up, towards chest and forehead bend
towards knees
Needle insertion site is cleaned with an antiseptic solution & local anaesthetic
agent is injected to numb area - feel brief stinging during the injection
A long needle is carefully inserted in to the spinal canal (L puncture), fluoroscopy is
used to guide in to the subarachnoid space, you may feel some pressure as the
needle is inserted
Contrast dye is injected through the needle into the spinal canal. Feel a transient
flushing sensation, warmth, a headache, a salty taste or nausea after the
material is injected
The flow of contrast agent is followed using fluoroscopy, and represent active x-
ray films are obtained for any abnormalities
Once the procedure was completed, the needle should be removed
The puncture site cleaned with any antiseptic solution & dressing is applied
The procedure usually take about 1hr

31. CONVENTIONAL
RADIOGRAPHIC POSITIONS
LUMBAR MYELOGRAM

32. LUMBAR
MYELOGRAM

33. ☛Preliminary images:-
AP & lat: projections study are taken
Preliminary radiographs is helpful to assess the
anatomy of spine
There is a potential danger of operating at the
wrong level if this is not made explicitly clear in
the report
A clear description of any anomaly is required,
together with a statement of how the vertebrae
have been numbered in the report.

34. ☛Radiographic views:-
AP & Oblique views are obtained.
(about 25 degrees of obliquity is typical, but this should be
tailored in the individual case to profile the exit sleeves of the
nerve roots of the cauda equine)
A lateral view with horizontal beam is useful, but
further laterals in the erect or semi eruct position
on flexion & extension add a dynamic dimension to
study

35. LATERALAP OBLIQUE

36. ☛After the myelogram :-
If oil based contrast agent was used, must lie flat in bed upto 12hrs and
your head raised at least 30degrees after the procedure.
If a water based dye was used, you must rest for about 6 - 8hrs
Your BP &other vital signs checked periodically & you will be monitored
for signs of complications
You may return home, if there are no complications (or) advert
reactions, you may resume your normal diet and activities the day
after the test
You are encouraged to drink clear fluids to avoid dehydration and helps
to flush the contrast dye out of your system (if lumbar
puncture was done, extra fluids helps to replacement the speed of CSF)
Delayed allergic reactions to the contrast dye may appear to 2-6hrs
after procedure. If this occurs, your doctor will prescribe
antihistamines (or) steroids to ease your discomfort.

37. ☛Risk & Complications:-
Radiation exposure is minimal, but if the test including
CT scan, you will receive higher dose of radiation
Headache (or) soreness in the back may occur for a
short time after the procedure. Rarely serious
complications, such as meningitis / seizure may be
developed
Some people may experience an allergic reaction to the
iodine based contrast dye, which can cause symptoms
such as nausea, sneezing, vomiting etc
If a lumbar puncture is performed, it carries the
associated risks
You may experience temporary leg numbness or lower
back pain

38. ☛Result :-
The doctor will examine the x ray or CT images & other
test data for evidence of abnormalities such as blocked
or narrowed areas affecting the spinal canal or base
of the brain
A sample of CSF is taken it will be send to a laboratory
for analysis to provide further diagnostic informations
Definite diagnosis can be made, your doctor will
recommended an appropriate course of medical or
surgical treatment, depending on the specific problem
In some situations, additional diagnostic test, such as
skeletal MR, may be needed to further evaluate
abnormal results

39. ☛Limitations of Myelogram :-
Its only sees inside the spinal canal & the
very proximal nerve roots. Abnormalities
outside these areas may be better imaged
with MRI
It may be difficult to inject contrast
material in patients with structural defects
of the spine or some forms of spinal injury
Myelogram usually is avoided during
pregnancy.

40. ☛Refarance:-
Interventional Radiology for Medical Students - Hong
Kuan Kok
Practical Radiological Anatomy - Sarah McWilliams
Articles for American Radiological Journal - Google

41. “Type a quote here.”
–Johnny Appleseed