Peripheral fundus & its disorders

1. Peripheral fundus & its disorders
Presented by Dr Rohit Rao

2. References
• Peripheral Ocular Fundus 3rd edition by
William L. Jones
• Ophthalmology 3rd edition.by Yanoff, Duker
• Clinical ophthalmology 7th Edition - Jack
Kanski
• Wolff's Anatomy of the Eye and Orbit 8th by
Bron, Tripathi.
• Retina by Stephen.J .Ryan

3. Retina
Optic Disc
Peripheral Retina
Ora Serrata
Area
Centralis
Perifoveal
Parafoveal
Fovea
Foveola

4. Near Periphery: 1.5mm
Around Area Centralis
Periphera
Retina
Mid Periphery: 3mm Wide Zone
Around Near Periphery
Far Periphery: Extendes From Optic Dics,
9-10mm Temoprally & 16mm Nasally

5. N
T

6. Pars plana
• Ciliary body starts 1 mm from the limbus and
extends posteriorly for about 6 mm.
• First 2 mm pars plicata and 4 mm pars plana.
• Width is about 4.0-4.5 mm.

7. Vitreous base
• Vitreous base is a 3–4 mm wide zone straddling
the ora serrata.
• Vitreous is strongly attached at base, so that
following PVD, posterior hyaloids face remains
intact.
• Pre-existing retinal holes within the vitreous
base do not lead to RD.
• Severe blunt trauma may cause tearing of nonpigmented epithelium of pars plana & of retina.

9. Ora Serrata
• Retina becomes opalescent and often is marked
by small rows of cystoid cavities.
• Extensive cystoid changes do not represent
pathology.
• Neural retina stops abruptly at ora serrata and is
continued by nonpigmented ciliary epithelium
• Pars plana is more deeply pigmented, so
choroidal pattern not seen.

11. 0.7-0.8
mm
N
2.1 mm
7.0 mm
T
N
6.0 mm
7.0 mm
7.0 mm
T

12. • Dentate processes are teeth-like extensions of
retina onto the pars plana.
• Oral bays are the scalloped edges of the pars
plana epithelium in between the dentate
processes.
• Enclosed oral bay is a small island of pars
plana surrounded by retina as a result of
meeting of two adjacent dentate processes.
▫ Not be mistaken for a retinal hole
• Granular tissue characterized by multiple
white opacities within the vitreous base
▫ Can be mistaken for small peripheral opercula.

13. Enclosed
oral bay
Granular
tissue

14. Meridional fold
• Small radial fold of thickened retinal tissue in line
with a dentate process,
• It bigns at ora serrata and runs posteriorly &
perpendicularly to it in a meridional fashion
• Superonasal quadrant .
• Small retinal hole at its apex
• Found in approximately 20% of all eyes
• Meridional complex is composed of an enlarged
dentate and ciliary process associated with a
meridional fold

15. • Vitreous traction on meridional folds and
complexes may result in the formation of retinal
breaks.
• Meridional folds are not a common cause of
RD, may be because these are found at vitreous
base.
• Because of anterior location , cryopexy is

17. Pars plana cyst
• Pars plana cysts are clear cystoid spaces between the
pigmented and nonpigmented epithelia.
• Scleral depression
• Fluid contains hyaluronic acid.
• Mostly acquired; few are congenital.
• idiopathic or secondary to ocular disease.
▫ Retinal detachment, may be the result of traction by
the shrinking vitreous base.
▫ Posterior uveitis.
▫ Multiple myeloma

19. Congenital Hypertrophy of the
Retinal Pigment Epithelium
• Common benign lesion.
• Congenital and not a degenerative condition.
• Flat round or oval lesion, well defined, dark grey
or black in colour and up to three disc diameters
in size.
• Outer retina change and does not affect the
vitreo-retinal interface; so does not predispose
to RD.
• Can lose pigment over time

20. • When occur in groups, known as bear
track, Familial Adenomatous Polyposis.

23. Pavingstone(Cobblestone degeneration
or Chorioretinal Atrophy)
• 25% of the population
• Well defined yellow white patches between the
equator and the ora serrata.
• Absence of the outer layers of the retina, in
particular the choroid, which permits an
uninterrupted view of the sclera.
• Congenital and not be considered a
degeneration.
• No predisposition to break formation

26. Microcystoid degeneration
• Tiny vesicles with indistinct boundaries.
• Always starts adjacent to ora serrata and extends
circumferentially and posteriorly with a smooth
undulating posterior border.
• Present in all adult eyes,
• Increasing in severity with age
• Although it may give rise to retinoschisis.
• Do not give rise to RD

28. Honeycomb (reticular) degeneration
• Age-related change
• Fine network of
perivascular
pigmentation which
may extend posterior
to equator.
• Caused by RPE
degeneration
• More prominent in
nasal quadrant

29. Snowflake Vitreoretinal Degeneration
• Snowflake vitreoretinal degeneration appears as
tiny yellow-white spots in the far peripheral
retina
• Superior temporal quadrant
• Lattice degeneration
• Vitreous shows fibrillar degeneration &
liquefaction.

31. Lattice degeneration
•
•
•
•
•
•
•
•
•
•
An Area with Absence of ILM
Overlying Area of Liquefied Vitreous
Condensation & Adherence of Vit Gel
Inner Retinal Layer Atrophy
More common superiorly
Arranged parallel to the ora serrata.
Incidence- 8% to 10%
RRD :: Lattice account for 20%
Symmetric and bilateral,
Horse shoe Tears &Atrophic holes

34. Complications
(A) Atypical
radial lattice
without
breaks;
(B) U-tears
(C) Linear tear
along
posterior
margin.
(D) multiple
small holes
within
islands of
lattice

35. Management of Lattice Degeneration
•
•
•
•
Lattice without Retinal Breaks - No Rx
Lattice with Atrophic Holes - No Rx
Lattice + Holes+ Sub clinical RD – Treat
Lattice+ Traction Tear - Treat : If Fellow eye has
RD,Strong Family History of RD,Aphakic Eyes
• Asymptomatic Traction Tear - No Rx
• Acute Symptomatic Tears - Treat in Phakics &
Aphakics

36. Vitreoretinal Tufts
• Small Peripheral Retinal Elevation
• Focal Vitreous Traction
• Operculated or flap tears when strong vitreous
traction is applied
• Rarely cause retinal detachments.
• Treatment is rarely indicated
• Cryopexy or photocoagulation.

38. Snailtrack degeneration
• Snailtrack degeneration is characterized by
sharply demarcated bands of tightly packed
‘snowflakes’ which give the peripheral retina a
white frost-like appearance.
• Longer than in lattice degeneration
• Overlying vitreous liquefaction.

40. Degenerative retinoschisis
• 5% of the population over the age of 20 years and
is particularly prevalent in hypermetropes.
• Bilateral
• Coalescence of cystic lesions
• Results in separation or splitting of the NSR into an
inner (vitreous) layer and an outer (choroidal).

41. • Typical retinoschisis split is in outer plexiform layer,
• Reticular retinoschisis, less common, splitting occurs
at level of NFL.
• Early retinoschisis seen in inferotemporal with a
smooth immobile elevation of retina.
• Progress circumferentially
• Snowflakes , sheathing or ‘silver-wiring’ of blood
vessels.
• Microaneurysms and small telangiectases ,
• Complications are very rare,
• Breaks, RD in the presence of PVD, Vitreous
haemorrhage

44. White with pressure
• Translucent grey appearance of the
retina, induced by indention.
• It does not move when indenter is moved.
• Normal eyes and may have abnormally strong
vitreous attachment.
• It is also observed along the posterior border of
islands of lattice degeneration, snailtrack
degeneration and the outer layer of acquired
retinoschisis.

46. White without pressure
• Has the same appearance but is present without scleral
indentation.
• May be mistaken for a flat retinal hole.
• Giant tears occasionally develop along the posterior
border of ‘white without pressure’.
• For this reason, if ‘white without pressure’ is found in the
fellow eye of a patient with a spontaneous giant retinal
tear, prophylactic therapy should be performed.
• It is advisable to treat all fellow eyes of non-traumatic
giant retinal tears prophylactically by 360° cryotherapy
or indirect argon laser photocoagulation, irrespective of
the presence of ‘white without pressure’, if they have not
developed a PVD.

48. TREATMENT
• Upon the discovery of a retinal break, the initial decision
is whether the benefits of treatment (to prevent retinal
detachment) outweigh the risks and cost of treatment
• The factors under consideration in each case include
▫
▫
▫
▫
▫
▫
Presence or absence of symptoms;
Age and systemic health of the patient;
Refractive error of the eye;
Location, age, type, and size of the break;
Status of the fellow eye;
Whether the patient is aphakic, pseudophakic, or will soon
undergo cataract surgery

49. • Retinopexy
• Cryopexy and laser photocoagulation.
• Cryotherapy
▫ Delivered transconjunctivally.
▫ It destroys the choriocapillaris, RPE, and outer retina
to provide a chorioretinal adhesion
▫ It is not immediate; 1 week for partial adhesion and up
to 3 weeks for the complete.
• Laser photocoagulation
▫ Argon green, argon blue-green, krypton red, or diode
laser.
▫ Slit lamp and the indirect ophthalmoscope.
▫ Instant, but maximal adhesion occurs 7–10 days later.

50. • Cryopexy has the advantage of not requiring
clear media
• In general, retinal cryopexy and indirect
ophthalmoscopic laser photocoagulation are
preferred for anterior retinal breaks
• Similarly, posterior breaks managed with the
slit lamp or an indirect laser delivery system.
• Retinal tear with persistent traction and
recurrent vitreous Hemorrhage requires scleral
buckling or vitrectomy

51. Cryopexy
• Indirect ophthalmoscopic visualization,
• Cryoprobe is placed on the conjunctiva that overlies
the break until the retina adjacent to the tear
becomes gray-white.
• Approximately 2 mm of retinal whitening around
the entire break
• Multiple applications are placed until the break is
surrounded completely with confluent treatment.
• Do not to treat the choroid and RPE directly beneath
the break, can lead to macular pucker and
proliferative vitreoretinopathy.

52. Photocoagulation
• Goldmann three-mirror lens or panfundoscope lens
with the slit-lamp delivery system.
• Tear should be surrounded completely by three to
four rows of laser burns.
• Settings are 200–500 mm spot size and 0.1–0.2
seconds
• Indirect laser delivery system can also be used
• Advantage is simultaneous scleral depression
allows treatment of anterior tears and even dialysis.

53. Thank you