## Retinal breaks/degenerations
A full thickness defect in the neurosensory layer of the retina

- Holes
    - Atrophic: not associated with vitreoretinal traction, therefore no increased risk of retinal detachment
    - Operculated: less risk compared to HST, but may be treated with laser if the patient is symptomatic, persistent traction, superior or large holes.

- Tears
    - Horseshoe/flap: high incidence of progression to retinal detachment. Almost universal vitreous traction along the edge of the flap
    - Giant retinal tear: greater than 3 clock hours circumferentially, developing from vitreous base or lattice degeneration

- Dialysis:
    - Break originating from the ora. Vitreous base is attached. 10% of RRDs.

- Lattice degeneration: area of retinal thinning due to discontinuity of ILM with crossing white lines and small round holes. Associated with Stickler’s, Marfan’s, Ehlers-Danlos. Not treated prophylactically unless risk factors (see below)
- White-without-pressure: may be treated if fellow eye has had a GRT
- Retinoschisis: may be treated if double layer break

- Benign degenerations:
    - Retinal hyperplasia
    - Microcystoid change
    - Honeycomb/reticular degeneration
    - Snowflake degeneration
    - Pavingstone degeneration
    - Peripheral drusen
    - Pars plana cyst

### Indications to treat a retinal break

- Symptomatic
- Subclinical RD
- Horseshoe tear (ie. U-shaped)
- Large tear
- Location: superotemporal/posterior
- Only eye or fellow eye with previous RD
- High myope
- Vitreoretinopathy or systemic risk factor such as Marfan’s/Stickler’s

<HotTopic>

**Lincoff’s rules**: four guidelines for locating retinal breaks causing RRD

Only apply to primary rhegmatogenous retinal detachments

- Superior or temporal detachments: hole lies within 1.5 clock hours of the highest border (98% of the time)
- Total or superior detachments that cross the 12 o’clock meridian: the primary hole is at the 12 o’clock position or within a triangle extending between the ora (apex) and 1 clock hour either side of the 12 o’clock position (93% of the time)
- Inferior detachments: the higher side indicates the side of the break (95% of the time)
- Bullous inferior detachments: the primary break lies above the horizontal meridian.

</HotTopic>

## Other rules/guidelines
- Inferior detachments with equal height on both sides: break is likely at 6 o’clock

## Retinoschisis

- Splitting of the retina
- Degenerative retinoschisis:
    - More common in **hypermetropes**
    - Typically bilateral (50-80%)
    - Senile form (most common): split in the outer plexiform layer/inner nuclear junction
    - Reticular (less common) form: split in the nerve fibre layer, similar to X-linked juvenile retinoschisis
        - More likely to develop retinal detachment

    - Both inner and outer leaf breaks are needed for secondary RD to occur

### Clinical features

- Asymptomatic unless very posterior extension
- **Absolute** field defect (compared to relative for RRD)
- Usually found inferotemporally (in 72%)
- Laser reaction (cp. Retinal detachment)
- Smooth surface with absent pigments

### Complications
- Inner leaf breaks
- Outer leaf breaks
- Retinal detachment:
    - Low risk type due to outer leaf break only
    - High risk rhegmatogenous type: both inner and outer leaf break with full thickness retinal elevation

## Retinal detachment types

### Rhegmatogenous
- Associated with retinal breaks
- Corrugated surface
- Pigment and/or blood in vitreous
- Static fluid

### Exudative
- No breaks
- Smooth surface
- Inflammatory cells may be present in vitreous
- Shifting fluid

### Tractional
- Preretinal fibrosis (no breaks)
- Smooth surface
- Clear vitreous
- Minimal or no fluid

## Proliferative vitreoretinopathy (PVR)
- RPE cells migrate into vitreous through a retinal break
- Convert to myofibroblasts and release transforming growth factor
- Fibrosis and contracture occur leading to tractional RD

- Risk factors
    - Multiple or large breaks
    - Vitreous haemorrhage
    - Recurrent detachment
    - Excessive cryotherapy or laser treatment
    - Silicone oil
    - Iris trauma

### Retina society classification (1991)
- A: vitreous haze and pigment clumps
- B: retinal wrinkling, rolled edges, stiffness and vessel tortuosity
- C (multiple sub-classes): subretinal strands

### Management
- Surgery +/- pharmacological adjuncts (5-FU).
- Early surgery if macula preserved to protect vision

- Silicone Study (1992)
    - Compared silicone oil vs gas for PVR associated with RRD
    - Oil was more effective than SF6 gas, but equal to C3F8.

## Retinal detachment surgery
### Overarching principles
- Identify all breaks: can begin preoperatively, informed by Lincoff’s rules
- Seal breaks: cryotherapy or laser
- Drain subretinal fluid: not always necessary as long as break and traction addressed
- Relieve vitreoretinal traction: buckle, vitrectomy, or pneumatic retinopexy

### Cryotherapy
- Freezing treatment (probe is between -40 and -70) turns water to ice causing cell death
- Sterile inflammatory reaction
- Retinal adherence fully develops over 2 weeks (note: retinopexy is faster)

- Indications
    - To seal retinal breaks, especially where laser difficult due to
        - Small pupil
        - Far-peripheral retina
        - Media opacity

    - To treat pathological blood vessels eg. Coat’s or proliferative DM
        - Similar indications to above

    - Cyclodestruction (ciliary body) in glaucoma
    - Certain lid or intraocular tumours

- Complications
    - Pain
    - Conjunctival fibrosis: risk of bleb failure in trab patients
    - Inflammation: vitritis, CMO
    - PVR
    - Muscle injury
    - Scleral damage/necrosis
    - Epiretinal membrane

### Scleral buckles
- Types
    - Placement
        - Radial
        - Segmental
        - Encircling

    - Material
        - Silicone
        - Hydrogels: more expensive and not used due to risk of complications
        - Gelatin: temporary

- Indications
    - Radial buckles: large U-shaped tear or posterior breaks
    - Segmental buckles: multiple breaks
    - Encircling band: breaks over >two quadrants, complex RD, mild PVR, previous failed segmental buckle

- Complications
    - Intraoperative: perforation, muscle damage, fish-mouthing, remaining break
    - Early: anterior segment ischaemia, angle closure, re-detachment, endophthalmitis, vitritis (from cryotherapy)
    - Late: extrusion/exposure or buckle infection, epiretinal membrane, PVR, diplopia, glaucoma

### Vitrectomy
- Indications
    - RRD (uncomplicated and certain complicated cases)
        - RD with vitreous haemorrhage
        - Severe PVR
        - Giant retinal tear

    - Tractional RD
    - Advanced diabetic retinopathy
    - Trauma with intraocular foreign body
    - Epiretinal membrane
    - Macular hole
    - Post-operative endophthalmitis
    - Dropped nucleus
    - Aqueous misdirection
    - Diagnostic: chronic inflammation

- Complications
    - Intraoperative
        - Iatrogenic break
        - Vitreous haemorrhage
        - Suprachoroidal haemorrhage
        - Lens trauma

    - Postoperative
        - Vitreous haemorrhage
        - Choroidal haemorrahge
        - PVR
        - Recurrent detachment
        - Glaucoma
        - Cataract: almost inevitable
        - Band keratopathy
        - Endophthalmitis

- Intraocular gases
    - Uses:
        - Vitreous replacement after vitrectomy since they are optically clear, inert and highly buoyant (provide greater force than silicone oil).
        - Retinal tamponade eg. pneumoretinopexy

    - Non-expansile: air, nitrogen, helium
    - Expansile:
        - SF6: persists for 2 weeks. Expansion volume is x2 (nonexpansile concentration is 20%)
        - C2F6: persists for 3 weeks. Expansion volume is x3 (nonexpansile concentration is 18%)
        - C3F8: persists for 6-8 weeks. Expansion volume is x4 (nonexpansile concentration is 15%)

  - Silicone oil
      - Has similar properties to gases however may emulsify due to lower surface tension. Heavy oil can be used for inferior detachments (heavier than water)
      - Uses
          - Longer lasting volume replacement eg. PVR, GRT, control of vitreous haemorrhage (longer lasting tamponade), patients who **cannot posture**
      - Provides better immediate post-operative vision

    - Complications
        - Glaucoma
            - Angle closure from pupil block (iridectomy usually needed inferiorly)
            - Open angle from emulsified oil
        - Cataract
        - Band keratopathy
        - Inflammatory reaction to oil: uveitis, retinal toxicity
        - Epiretinal membrane
        - Recurrent detachment

### Pneumoretinopexy
- Tamponade of break with intravitreal expansile gas
- Indicated for superior breaks only
- Avoids need for admission or complications of other procedures
- However may fail and carry risks of CRAO, gas migration, and new breaks

### X-linked juvenile retinoschisis
- XLRS1 gene
- Abnormal intercellular adhesion molecule leading to retinal splitting at the NFL
- Poor visual prognosis: presents in early childhood with stellate/cystoid maculopathy which progresses to a macular scar
- Foveal schisis with spoke-like folds
- Non-specific atrophy
- Vitreous haemorrhage
- Retinal detachment in 5%
- Associated with hypermetropia
- Electronegative ERG: reduced b wave
- No systemic findings

### Stickler’s syndrome
- Autosomal dominant abnormality of **type II collagen** production (COL2A1)
    - An autosomal recessive form is also recognised

- Aka ‘hereditary arthro-ophthalmopathy’
- Ocular features
    - Myopia
    - Empty vitreous
    - Lattice-like pigmentary perivascular changes
    - Strabismus
    - Retinal tears, giant retinal tears and retinal detachment
    - Cataract: comma-shaped cortical opacities
    - Ectopia lentis
    - Open angle glaucoma

- Systemic
    - Epiphyseal dysplasia: degeneration of large joints
    - Cleft palate
    - Abnormal uvula (bifid)
    - Mid-facial flattening
    - Pierre-Robin sequence: micrognathia, glossoptosis
    - Sensorineural deafness
    - Mitral valve prolapse
    - Marfanoid habitus

- Clinical diagnosis with molecular genetic testing

- Management
    - Prophylactic retinopexy for extensive lattice
    - Refractive correction for myopia to avoid amblyopia

### Wagner syndrome
- Autosomal dominant vitreoretinopathy
- Optically empty vitreous
- Myopia
- Retinal detachment


Retinal breaks/degenerations A full thickness defect in the neurosensory layer of the retina Holes Atrophic: not associated with vitreoretinal traction,…

Surgical Retina

Retinal Detachment

Intro

FRCOphth Part 2 Study Notes

Tumours, masses and neoplasia

Tumours overview

Uveitis

Uveitis background

Anterior uveitis

Intermediate uveitis

Uveitis in JIA

Uveitis with JIA

Retinal vasculitis

Sarcoidosis

Behcet's disease

Toxoplasmosis

Viral uveitis

Strabismus

Overview

Esotropia

Fungal uveitis

Mycobacterial uveitis

Adnexal masses

Spirochaetal uveitis (including Syphilis)

Exotropia

Melanoma

Nematode uveitis

Retinoblastoma

Retinoblastoma (for Part 2)

Incomitent

Voyt-Koyanagi-Harada syndrome

Conjunctival intraepithelial neoplasia

Vertical deviations

Sympathetic ophthalmia

Orbit and ocular adnexae

Orbit

AV Malformations and hamartomas

Arteriovenous malformations and hamartomas

Restriction syndromes

Paediatrics

Leucocoria

Congenital Cataract

Paediatric Glaucoma

Retinopathy of prematurity

Retinopathy of Prematurity

ROP-like disorders

Congenital nasolacrimal duct obstruction

White dot syndromes

Aniridia: Short Arm 11 Deletion (11p13)

Choristomas

Management Of Amblyopia

Alphabet patterns

Scleritis

Iris Nodules

Meningioma

Strabismus surgery

Optic nerve glioma

Lymphoma

Extraocular Muscles

Rhabdomyosarcoma

Idiopathic orbital inflammation

Orbital neuroblastoma

Anterior Persistent Foetal Vasculature

Lacrimal system

Metastatic lesions

Vitreoretinal Interface And Macular Hole

Epiretinal Membrane

Medical Retina

Diabetic Eye Disease

Orbital Blood Vessels

Retinal Vascular Disease

Macular Degeneration

Central Serous Chorioretinopathy (CSCR)

Sickle Cell Retinopathy

Retinitis Pigmentosa

Albinism

Retinal Telangiectasias

Miscellaneous Retinopathies

Atropine And Myopia Progression

Pharmacology

Side Effects Of Systemic Drugs

Foetal Alcohol Syndrome

Neuro-ophthalmology

Optic Neuropathy

Papilloedema

Idiopathic Intracranial Hypertension

Chiasmal Disorders

Retrochiasmal Disorders

Migraine

Paranasal Sinuses

Supranuclear Motility Disorders

Third Nerve Palsies

Fourth Nerve Palsies

Sixth Nerve Palsies

Seventh Nerve Palsies

Anisocoria

Myasthenia Gravis

Myopathies

Blepharospasm

Functional Visual Loss

Lacrimal Glands

Phakomatoses

Developmental diseases

Tear Film

Eyelids

Blinking

Lid Malpositions

Anterior segment - ocular surface

Conjunctiva

Conjunctivitis

Sclera

Pigmented Conjunctival Lesions

Squamous Cell Carcinoma Of The Conjunctiva

Ocular Cicatricial Pemphigoid

Cornea

Corneal Structure And Development