Retinal detachment in childhood

Blunt ocular trauma

Retinal dialysis

Retinal detachment due to blunt trauma is usually caused by a disinsertion at the ora serrata in older children. Sudden anteroposterior compression of the globe with a violent coronal expansion leads to retinal avulsion ( Fig. 51.1A ) characterized by a festoon of non-pigmented pars plana epithelium in the vitreous cavity. This is the hallmark of a traumatic retinal dialysis and there may be signs of related orbital injury ( Fig. 51.2 ) or, more frequently, subtle signs of collateral trauma to the iris, lens, or drainage angle. Superior quadrant involvement is more frequent than the lower temporal quadrant involvement seen in non-traumatic dialysis ( Fig. 51.3 , and see Fig. 51.1B ). Although the disinsertion may exceed 90 degrees, the vitreous characteristically remains attached to the posterior flap so that the independent mobility that characterizes a true giant retinal tear (GRT) is not a feature. Dialyses, therefore, respond very well to conventional scleral buckling techniques. Further distinguishing features from a giant tear are the absence of radial extensions, which frequently occur at the apices of GRTs ( Fig. 51.4 ) and the normal compact healthy vitreous architecture. Subretinal fluid recruitment in dialyses is typically slow, so that unless the ora serrata is routinely inspected after blunt trauma, the diagnosis may be delayed by weeks or months until macular involvement.

Ragged impact necrosis breaks account for about one-fifth of the retinal breaks in blunt trauma. Retinal vessel and retinal pigment epithelial disruption may be confirmed on fundus fluorescein angiography and retinal detachment usually presents within 6 weeks. These breaks are often large, post-equatorial, and irregular, making closure by external buckling problematic and an internal approach is more usually required.

Giant retinal tears

True GRTs account for a minority of retinal breaks due to blunt trauma. They are best managed with vitrectomy and internal tamponade (see below) although the visual prognosis may be limited by associated collateral ocular trauma ( Fig. 51.5 ).

Penetrating ocular trauma

Penetrating injury is an uncommon cause of retinal detachment in childhood. Intraocular foreign bodies are rarely seen in very young children, although penetrating injuries from air-gun pellets may be seen in older children and adolescents. The prognosis is usually poor because of the associated collateral damage and aggressive PVR. Retinal perforation or incarceration from penetrating trauma rarely causes acute rhegmatogenous retinal detachment. The corneoscleral wound provides access for extrinsic fibroblasts so that the more common sequel is late tractional and rhegmatogenous retinal detachment.

Non-traumatic retinal dialysis

Non-traumatic retinal dialysis accounts for approximately 10% of all juvenile retinal detachment and in 97% affects the inferotemporal quadrant (see Fig. 51.1B , Table 51.1 ). Examination of the entire retinal periphery may reveal two or more separate dialyses in the same eye. There is a 2:3 male propensity and the majority are hypermetropic or emmetropic. Detachments associated with dialyses progress slowly and usually present either as an incidental finding or when the macula becomes detached. They are routinely managed with conventional buckling. Although the anatomic success rate of surgery is high, visual recovery may be limited if there has been chronic macular involvement. Familial dialyses are rare, but consideration should be given to sibling examination because (1) the patients are asymptomatic and (2) visual recovery once macular involvement has occurred may be poor. Examination of the fellow eye under anesthesia is important as retinal dialysis may be bilateral and abnormalities of the ora serrata, in the form of a “frill” or flat dialysis, are found in the fellow eye in up to 15% (see Table 51.1 ). In such cases, prophylactic retinopexy should be applied to the fellow eye to avert detachment with potential macular involvement.

Ocular coloboma

Eyes with colobomas are at increased risk of detachment and account for approximately 0.5% of pediatric retinal detachments forming part of the spectrum of wider systemic developmental abnormality ( Fig. 51.6 ). GRTs may be seen in association with lens colobomas. Rhegmatogenous detachment may also develop in eyes with choroidal coloboma, when small retinal breaks occur in the hypoplastic retina overlying the coloboma. Assessment of vision can be difficult and the diagnosis of detachment can be further impaired by restricted pupil dilation, nystagmus, microphthalmos, and cataract ( Fig. 51.7 ). The intercalary membrane stretched across the coloboma cavity can simulate a retinal detachment on ultrasound examination. The clinician should be alert to this and assess the retinal mobility on dynamic examination before deciding whether surgical intervention is indicated. The intercalary membrane consists of hypoplastic inner retina with reversal and duplication of outer neuroblastic layers at the coloboma margin. Both retinal pigment epithelium and Müller cells are vestigial or absent within the coloboma; thus, effective retinopexy may be impossible to achieve unless applied outside the margin of the coloboma.

Where retinal breaks occur away from the coloboma, they may be managed by conventional buckling provided the sclera is of sufficient quality and the break can be adequately closed. More usually, the retinal break lies within the coloboma ( Fig. 51.8 ) so that identification and closure with retinopexy may be impossible without an internal approach. Retinal breaks over a coloboma are often small, multiple, and difficult to visualize against the pale scleral background. The break(s) may be confirmed peroperatively by visualization of proteinaceous subretinal “ schlieren” which appears during internal drainage. Laser may be applied around the border of the colobomatous area and where this includes the papillomacular bundle it may be applied prior to retinal reattachment to minimize thermal damage to the nerve fiber layer. An adequate tamponade may be difficult to obtain because of the abnormal configuration of the colobomatous globe. Recurrent detachment may occur in up to 30%, necessitating permanent internal tamponade.

Optic disc pits and macular detachment

The association of serous macular detachment and optic disc pits and coloboma is well recognized and similar findings with the morning glory disc abnormality suggest that these conditions are variations of the same abnormality ( Fig. 51.9A-D ). The vitreous is characteristically attached. It has been suggested that up to 45% of optic disc pits may be complicated by serous retinal detachment.

Although natural history studies have shown eventual spontaneous reattachment in 25% of cases the combination of vitrectomy, laser photocoagulation, and gas tamponade may offer a greater chance of visual improvement, albeit at greater risk of operative morbidity.

Vitreoretinopathies with skeletal abnormalities

Vitreoretinopathies associated with skeletal abnormalities form the largest subgroup ( Table 51.2 ). Of these, the Stickler syndromes in various guises account for the majority.