Retinal Detachment

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54 Retinal Detachment

Table 54.1 Detachment of the retina: types and characteristics*

Detachment

Comment

Rhegmatogenous

A retinal break (ÒrhegmaÓ) is present, but the primary culprit is VR

(ÒRDÓ)

traction, which is dynamica

The conÞguration is convex

Tractional (ÒTRDÓ)b

There is very strong VR or subretinal traction, but no break. The

traction is staticc

The conÞguration is concave

Combined

The tractional component dominates, even though a break is also present.

rhegmatogenous

The tractional element precedes the development of the break

and tractional

The conÞguration is concave

Central (posterior,

Although VR traction is presente, the main culprit is the staphyloma;

staphyloma

the rigid ILM does not allow the otherwise elastic retina to conform

spanning)d

to the scleral bulge

A macular hole may be present, but it is likely to be the consequence,

not the cause of the RD

The conÞguration is convex or concave, depending on the size of the

staphyloma and the height of the RD

Exudative/serous

There is no traction, simply secretion of ßuid into the subretinal space.

The ßuid is either too voluminous or too viscous for the RPE to

remove. Examples include optic pit (surgical intervention is worth

considering, see Chap. 51) and central serous chorioretinopathy

(not a surgical indication)

The conÞguration is convex

Hemorrhagic

There is no traction; the bleeding is typically traumatic in origin or

associated with AMD

The conÞguration is initially convex but can become uneven as the

blood start to absorb

54.1 The Pathophysiology of RD

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Table 54.2 RD pathophysiology and treatment: traditional and revised concepts*

Variable

Traditional concept

Revised concept

PVD in old age in an eye

Very likely to be present

May or may not be present

with attached retina

PVD progressing in an

The highest risk for RD

True Ð except that the PVD may be

eye with attached

development

anomalous

retina

If VR traction is not seen

There is no VR traction

VR traction still may be present, but

at the slit lamp or on

it is undetectable with current

OCT

methodology and technology

PVD as a preoperative

Straightforward to make as

Impossible to make with any kind of

diagnosis

at least one of the

certainty:

following is present:

1. The distant surface seen on

1. On biomicroscopy (or

biomicroscopy (or on OCT)

on OCT) a surface,

may indeed be PVD but may

distant from the

also be the anterior wall of a

posterior retina

vitreoschisis cavitya

2. Weiss ring

2. The Weiss ring indicates that

the vitreous is detached at the

disc, but not necessarily that it

also detached elsewhere in the

posterior pole

PVD in an eye with RD

Always present

May be complete, partial, or

completely absent

Primary causative

The retinal break (the RD is

VR traction (the RD is

pathology in RD

ÒretinogenicÓ)

ÒvitreogenicÓ); the retinal break is

secondary to the traction

The initial element in the

PVD

Syneresis

cascade leading to

break/RD development

Whether a retinal break

Depends on the size of the

Depends on the strength of the VR

leads to RD

break (and possibly the

traction as well as on the RPE

strength of the VR

pump, the strength of the IPM,

traction)

and the resistance (tensile

strength) of the retina itself

The volume of the incoming ßuid

must exceed the capacity of the

RPE to remove it

Presence of an

Signals strong traction and

Signals strong past traction and thus

operculumb

thus signiÞcant RD risk

reduced RD risk

PVD in a highly myopic

Present

What is seen as a PVD is in reality a

eye with posterior RDc

vitreoschisis

PVD in PDRd

Present, anteriorly (Òtable-

A vitreoschisis is present, not a PVD

top RDÓ)

The VR interface in an

There is a complete PVD

The ÒPVD posterior to the break, but

eye with RD

posterior to the break but

no PVD anterior to the breakÓ

complete vitreous

statement may hold true for the

adherence to the retina

eye just examined

anterior to the break

However, the PVD may also be

incomplete (anomalous) or

nonexistent

(continued)

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