Retinal Detachment – Exudative

Description

A retinal detachment occurs when the retina’s sensory and pigment layers separate.

An exudative retinal detachment (ERD) is usually secondary to another pathology, with a breakdown in the normal inner or outer blood-retinal barrier allowing a build-up of fluid beneath the retina. Unlike rhegmatogenous retinal detachment, there is no full-thickness retinal break with sub-retinal ingress of vitreous.

Classification

ERD usually occurs in conjunction with another posterior eye disease that causes fluid leakage or bleeding (see table):

Symptoms

The patient may report metamorphopsia or blurring of central vision if the macula is involved. The visual disturbance may fluctuate, be affected by head position or be progressive.

Signs

ERD is evident as a dome-shaped serous elevation of the retina. The detached retina is usually smooth and retains its transparency and it does not extend to the ora serrata. The sub-retinal fluid can shift with eye or head movements, such that the fluid tends to settle inferiorly, or posteriorly when the patient is supine on their back. The tendency for the sub-retinal fluid to be mobile distinguishes an exudative detachment from other forms of retinal detachment. There is there is no full-thickness retinal break, rather there is usually accompanying pathology that has caused the breakdown in the blood-retinal barrier.

Prevalence

Rare (approximately 1/10,000). Overall, ERD is the least common form of retinal detachment, although more common in particular risk groups such as patients with conditions listed above.SignificanceCan cause devastating damage to vision if untreated.

Differential Diagnosis

Retinoschisis- Acquired Degenerative, Retinoschisis – Juvenile X-Linked, Retinal detachment – Rhegmatogenous, Retinal detachment – Tractional, Choroidal detachmentSee alsoSee list of conditions above, under Classification. Retinal detachment – classification, Lattice degeneration, retinal pigment epithelial detachment

Management

Urgent

A retinal detachment in which the macula is not yet involved is an ocular emergency needing treatment within 24 hours. If the macular has already detached, then treatment is still urgent, 48-96 hours.

Additional Investigations

Fluorescein angiography may assist in diagnosis and management of the underlying cause. B-scan ultrasound may be useful to assess the retina since dynamic evaluation is possible. B-scan ultrasound may be used dynamically to assess the mobility of the vitreous and retina.

Laser and Incisional Surgery

Surgery may be indicated for the underlying condition; it is not usually indicated for the exudative retinal detachment itself Review If the exudative detachment is mild, then no treatment may be required and review may be all that is necessary as spontaneous improvement is possible e.g. mild CSCR

Prognosis

The treatment and prognosis depends upon the underlying cause of the exudative retinal detachment

Figure 1.

Acute superior RD extending to the upper edge of the macula.

Table: Possible causes of exudative retinal detachment and examples
Category	Examples
Neoplastic	Melanoma Of The Choroid (Malignant melanoma), Choroidal Metastasis, Choroidal Hemangioma, Retinal Capillary Hemangioma, Retinoblastoma
Inflammatory disease	Vogt-Koyanagi-Harada (VKH) disease (autoimmune), posterior scleritis, Systemic lupus erythematosus, Sympathetic ophthalmia
Infectious	Toxoplasmosis, Syphilis, Lyme disease
Vascular	Coats’ Disease (Retinal Telangiectasia), von Hippel Lindau syndrome, Hypertension – malignant, Pregnancy (eclampsia)
Congenital anomalies	Morning Glory Syndrome, Optic Nerve Head Pit, Coloboma, Nanophthalmos
Idiopathic	Central Serous Chorioretinopathy (CSCR), Idiopathic Choroidal detachment (uveal effusion syndrome)