B-scan ultrasonography produces real-time images of ocular structures using high frequency sound waves. It is useful for evaluating conditions like retinal detachment, tumors, and vitreous opacities. The technique involves placing a transducer probe on the eye to emit ultrasound and receive echoes. Different probe positions provide transverse, longitudinal, or axial scans of the eye. Normal tissues like vitreous and retina appear echolucent or reflective on scans depending on their structure and composition. Pathologies are identified based on their appearance, location, and movement patterns seen on the images. B-scan ultrasonography is a non-invasive imaging method useful when the ocular media is opaque.

1. B-SCAN ULTRASONOGRAPHY
Presented By:
Dr. Rakshan Reyaz
PGY-2
GMC Srinagar

2. CONTENTS
• History
• Introduction
• Instrumentation
• Technique of Examination
• Indications
• Evaluation of Ocular Structures
• Ultrasound in Intraocular Pathology

3. HISTORY
• In 1880, Curie Brothers first demonstrated Piezoelectric Effect
• 1n 1949, Ludwig used ultrasound to detect gallstones.
• Ophthalmologic B Scan was first introduced by Baum and Greenwood
in 1958.
• Commercially developed by Coleman et al in 1970’s.
• Technique was emphasized by Karl Ossoinig.

4. INTRODUCTION
• B Scan Ultrasonography is an important adjuvant for the clinical
assessment of various ocular and orbital diseases.
• It produces grey scale, real time, two dimensional images of ocular
tissues
• Ultrasound is a:
 Longitudinal Wave
 Alternating Compressions and Rarefactions
 Frequency: Above 20,000 Hz
 Similar to Light Waves : Reflected, Refracted and Absorbed

5. ABDOMINAL
ULTRASOUND: 1-5
MHz
OPHTHALMIC
ULTRASOUND: 8-
10 MHz
ULTRASOUND
BIOMICROSCOPY:
35-100 MHz

6. Based on principles of Pulse Echo
Technology.
Echoes are generated at adjoining
tissue interfaces. Greater the difference,
stronger the echo.
Greater the Frequency – Greater the
Resolution – Lower the Penetration.
Lower the Frequency – Lower the Resolution
– Greater the Penetration

7. Sound waves from
Transducer
Hits the target
tissue
Echoes are
received by the
Receiver
Amplification of
signals
Display of image
on screen

8. INSTRUMENTATION
1. TRANSDUCER
2. AMPLIFIER
3. DISPLAY MONITOR

9. TRANSDUCER
• Device which converts Electrical
Energy into Sound Energy and vice
versa.
• Parts:
• Piezoelectric Plate
• Backing Layer
• Acoustic Matching Layer
• Acoustic Lens

10. • PIEZOELECTRIC ELEMENT:
• Generates Ultrasonic Waves.
• Coated on both sides with electrodes to which
voltage is applied.
• Oscillation of element generates the sound
waves
• Most common: Lead Zirconate Titnate
• BACKING LAYER:
• Located behind the Piezoelectric element
• Dampens excessive vibrations from probe
• Improves image resolution
• ACOUSTIC MATCHING LAYER:
• Located in front of the Piezoelectric element
• Reduces reflections from acoustic impedance
between probe and object.
• Improves transmission.

11. • ACOUSTIC LENS:
• Grey coloured rubber on tip.
• Helps in focusing Ultrasonic Waves as a beam.
• AMPLIFIER
• DISPLAY MONITOR

12. TECHNIQUE OF EXAMINATION
1. Modes of Ultrasound
2. Probe Positioning
3. Procedure

13. AA-MODE
• Time- Amplitude Mode
• Seen as vertical deflections from a
baseline
• For interpretation of tissue reflectivity
• Uses one beam of ultrasound
• Brightness Mode
• Image recorded as bright and dim
dots
• For anatomical information: provides
cross-sectional images of globe and
orbit
• Uses a parallel beam of ultrasonic
waves
B-MODE
MODES OF ULTRASOUND

14. A- SCAN B-SCAN

15. ULTRASOUND PROBE
• Emits focused sound beam at
frequency of 10MHz
• Mark on probe indicates beam
orientation
• Area towards which mark is directed
appears at the top of the echogram
on display screen

16. PROBE POSITIONING
TRANSVERSE
• Most Common
• Lateral extend
• 6 clock hours are
examined at a time.
• Probe is parallel to limbus
LONGITUDINAL
• Radial
• Anteroposterior extend of
lesion
• One clock hour examined
at a time
• Probe is perpendicular to
limbus
AXIAL
• Eye is held in primary
gaze
• Probe centered on the
cornea incorporating the
Lens

17. TRANSVERSE SCAN
• Produces circumferential slice through
several meridians
• If examining:
 Nasal Area: 12-6 clock hours
 Temporal Area: 6-12 clock hours
 Superior Area: 9-3 clock hours
 Inferior Area: 3-9 clock hours

18. LONGITUDINAL SCAN
• Probe marker towards centre of the
Cornea.
• Optic disc and posterior aspect of
globe.

19. AXIAL SCAN
• Probe centered on cornea
• Evaluates macular region
• Documents lesions and membranes in
relation to optic disc
• Decreased resolution of posterior
portion of globe.

20. PROCEDURE
• The patient is either reclining on a
chair or lying on a couch.
• Probe can be placed directly on
conjunctiva, cornea or on the lids
• Lowest possible decibel gain
consistent with the maintenance of
adequate intensity should be used.

21. ANTERIOR SEGMENT
1. Opaque Ocular Media:
• Corneal Opacities
• Dense Cataract
• Pupillary Membrane
• Hyphema/ Hypopyon
2. Clear Ocular Media:
• Iris, Ciliary Body Tumours
• Dislocation/ Subluxation of Lens
1.Opaque Ocular Media:
• Vitreous Hemorrhage
• Endophthalmitis/ Vitritis
• Intraocular Foreign Body
2. Clear Ocular Media:
• Retinal Detachment/Posterior Vitreous
Detachment/Choroidal Detachment
• Retinoschisis
• Tumours
POSTERIOR SEGMENT
INDICATIONS

22. EVALUATION OF OCULAR STRUCTURES
Amount of reflection of
ultrasound energy
Absorption of ultrasound energy
Angle of incidence of sound
Shape/ Size/ Smoothness of
interface

23. AMOUNT OF REFLECTED ENERGY
GAIN (decibels)
Higher Gain: displays weaker
echoes like Vitreous
Opacities
Better Penetration
Lower Gain: stronger echoes
like Retina and Sclera
Better resolution
NATURE OF
SURFACE
Radiopaqu
e
Radiotranslucen
t

24. ABSORPTION OF SOUND ENERGY
1. Absorption/ Attenuation: Gradually
all sound energy is absorbed as heat
eg Tumours
2. Shadowing: Sound is strongly
reflected, nothing passes through it.
Leaves dark shadows behind eg
Optic Nerve Head Drusen, Air Bubble
3. Reverberation: Collection of
reflected sounds bouncing back and
forth between tissue boundaries eg
Foreign Body

25. ANGLE OF INCIDENCE
• Probe should be held perpendicular
to the area of interest to achieve a
strong echo – Bright Image
• If held at an angle, some amount of
sound is reflected away – Dim Image

26. SHAPE, SIZE AND SMOOTHNESS OF
SURFACE
DOT LIKE LESIONS:
Vitreous Floaters, VH, Vitreous Exudates
MEMBRANOUS LESIONS:
PVD, RD, Vitreous membranes
MASS LESIONS:
Choroidal or Retinal Tumours

27. NORMAL ULTRASONOGRAPHIC
CHARACTERISTICS
• LENS: oval, highly reflective
• VITREOUS: echolucent
• RETINA, CHOROID, SCLERA: highly
reflective
• OPTIC NERVE: wedge shaped
acoustic void in Retrobulbar region
• EXTRAOCULAR MUSCLES:
echolucent, low reflective fusiform
structures
• ORBIT: highly reflective orbital fat

28. ULTRASOUND IN INTRAOCULAR
PATHOLOGY

29. VITREOUS

30. VITREOUS HEMORRHAGE
• Small, white echoes
• Fresh: dots and lines
• Old: brighter dots

31. VITREOUS DEGENERATION
• Vitreous syneresis appears as dot like
reflections
• High myopes, Senile Vitreous

32. ASTEROID HYALOSIS
• Formation of Calcium Soaps within
vitreous gel
• Bright , round signal on B Scan
• Each opacity has its own spike on A
Scan
• Crystals are suspended, exhibit
dynamics of vitreous movement

33. ENDOPHTHALMITIS
• Vitreous Opacities
• Membrane Formation
• Severe Cases: RD or choroidal
detachment

34. PERSISTENT HYPERPLASTIC PRIMARY
VITREOUS
• Strand of membrane from posterior
surface of lens to area of optic nerve
head
• Reduced Axial Length on Biometry

35. INTRAOCULAR FOREIGN BODY
• B Scan: very bright signal
• A Scan: Very tall spike
• Shows precise location and extend of
damage caused.

36. POSTERIOR VITREOUS DETACHMENT
• Membranous lesion
• May or may not be attached to the
optic disc (depending on grade)

37. RETINA

38. ACUTE RETINAL DETACHMENT
• Detached neurosensory retina
appears as a membrane in vitreous
space.
• Highly reflective sheet like tissue
• Mobile , slightly folded

39. CHRONIC RETINAL DETACHMENT
• Detached retina appears thickened
• Decrease in the aftermovement
amplitude of the retina due to
massive periretinal proliferation by
Muller cells and astrocytes.
• Vitreous contracts leading to funnel
shaped detachment. As it further
contracts, it leads to formation of
cyclitic membranes extending from
vitreous base
• Cysts , subretinal opacities

40. RETINAL
DETACHMENT
• Always attached to the optic disc
• 100% spike on A-Scan
• Moderate aftermovements (recent
RD)
• High echogenicity
• Visible on Low Gain
• With or without disc insertion
• <100% spike on A-Scan
• Marked aftermovements
• Low – Medium echogenicity
• Disappears on Low Gain
POSTERIOR VITREOUS
DETACHMENT
REFLECTIVITY OF THE PERIPHERY CAN DIFFERENTIATE BETWEEN THE
TWO IN DIFFICULT SITUATIONS LIKE TRAUMA AND INFLAMMATION

41. RETINOSCHISIS
• Splitting within the neurosensory
retina
• Inferotemporal quadrant
• Moderately elevated, thin smooth
dome shaped structure in the
periphery

42. COATS DISEASE
• Exudative detachment
• Aneurysmal malformations
• Yellow subretinal cholesterol deposits

43. RETINOBLASTOMA
• Intralesional calcification
• Size
• Extraocular tumour extension

44. CHOROID

45. CHOROIDAL MELANOMA
• Biconvex , Homogeneous lesion
• If tumour breaks through the Bruchs
Membrane: mushroom shaped lesion,
collar button lesion
• Solid tissue, therefore no
aftermovements.

46. CHOROIDAL DETACHMENT
• Smooth
• Dome shaped, thick membrane
• Does not insert into the optic disc
• When severe, detached choroid can
meet at the center of the globe –
retina to retina touch – Kissing
Choroidal
• Serous Choroidal Detachments :
Echolucent

47. • Hemorhaggic Choroidal Detachment:
Reflective
• A Scan:
o Maximally high (100%) spike
o Thick
o Double peaked ( retina & choroid)

48. METASTATIC CARCINOMA
• Solid
• Highly reflective thickening
• Usually dome shaped with central
cavitation

49. CHOROIDAL HEMANGIOMA
• Dome shaped
• Regular structure
• High internal reflectivity

50. CHOROIDAL OSTEOMA
• Plaque like
• Minimally elevated
• Highly reflective

51. TRAUMA

52. DISLOCATED LENS
• Lens seen floating in the vitreous or
lying against the retina
• Strands of vitreous may be attached
to it

53. PENETRATING AND PERFORATING
INJURY
• Penetrating injury: hemorrhage lines
up along the traumatic tract
• Perforating injury: posterior exit site is
present.
• Vitreous may be incarcerate both
anteriorly and posteriorly

54. OPTIC NERVE

55. • ACUTE OPTIC NEURITUS AND
PAPILLEDEMA:
Thickening of retrobulbar portion of optic
nerve
OPTIC NERVE CUPPING
COLOBOMA OF FUNDUS

56. POSTERIOR SCLERITIS
• Thickening of sclera
• Increased fluid in sub tenons space
and around optic disc :T-SIGN

57. ADVANTAGES
• Non invasive
• Performed in office setting
• No exposure to radiation
• Accurate assessment
• Easy follow up
• Limited penetration
• May require patient cooperation
DISADVANTAGES
PROS V/S CONS