The significance of imaging and treatment in lattice retinal degeneration
Prompt evaluation and adherence to guidelines for treatment recommendations for lattice retinal degeneration are essential to the preservation of vision and sight.
Lattice retinal degeneration is the most significant peripheral retinal change associated with retinal detachment. Generally, it is a stable condition and may not have symptoms and can present in patients of any age who have almost any refractive correction. From LRD, complications, such as retinal tears can develop, leading to retinal detachment.
Case reports
Figure 1. Color fundus photograph of the inferior retina of an 11-year-old patient. The elevated lesion is the snail-track form of lattice retinal degeneration on the prominence of a scleral indenter. The railroad-track feature at the left of the lesion is a short ciliary nerve.
Figure 2. Color fundus photograph of the superior retina of a 30-year-old patient. This another example of the snail-track form of lattice retinal degeneration. The vortex vein ampulla below the lesion shows that it is about 2 DD anterior.
Figure 3. Color fundus photograph of the superior retina of a 65-year-old patient. This another an example of lattice retinal degeneration. The appearance of a whitened retinal vessel representing the vitreous adherence within the lesion.
(Images courtesy of Leo Semes, OD, FAAO)
Case 1
An 11-year-old patient attended for his first ophthalmic evaluation. The only significant complaint was distance blur as evidenced by difficulty seeing at distance in his classroom. The medical, family, and personal histories were all noncontributory. Refraction revealed compound astigmatism (OD, +1.50 to 2.00 X 090; OS, +1.75 to 2.00 X 090) with visual acuity correctable to 20/20 in each eye. Ocular alignment showed no evidence of tropia with appropriate accommodative response. Examination of the anterior segment was unremarkable. Applanation tonometry was measured at 14 mm Hg and 16 mm Hg in the right and left eye, respectively. Dilated fundus examination revealed clear media, distinct optic disc margins, appropriate course and caliber of the retinal vasculature, and present foveal reflex in each eye.
Observation of the peripheral retina revealed lattice retinal degeneration (LRD) as illustrated in Figure 1 for the right eye, which was similar for the left eye. No other retinal abnormalities were observed in either eye. The patient and his parents were made aware of the findings and admonished of the symptoms and risks of retinal detachment. He was asked to return in 1 year or sooner if symptoms, as reviewed, developed. Further testing was not recommended.
Case 2
A 30-year-old woman attended for periodic ophthalmic evaluation. She had relocated recently to the area and was advised to seek regular evaluation because of a “retinal problem that could lead to retinal detachment”—the specific name of which she could not recall. The medical, family, and personal histories were all noncontributory. Refraction revealed plano results in each eye at distance with 20/20 visual acuity. Applanation tonometry was measured at 18 mm Hg OD and OS. Dilated fundus examination revealed clear media, distinct optic disc margins, appropriate course and caliber of the retinal vasculature, and present foveal reflex in each eye.
Observation of the peripheral retina revealed LRD as illustrated in Figure 2 for the right eye, which was similar for the left eye. No other retinal abnormalities were observed in either eye. The patient was made aware of the findings and advised on the symptoms and risks of retinal detachment. She was asked to return in 1 year or sooner if symptoms, as reviewed, developed. No additional imaging was indicated.
Case 3
A 65-year-old man attended for scheduled follow-up for age-related macular degeneration (AMD) and LRD, which were both present in each eye. He had been identified with stage 1 AMD according to the Beckman scale, putting him at low risk for progression to vision loss over the next decade.1 His LRD was the only peripheral retinal abnormality noted at previous examinations. Significantly, posterior vitreous detachment (PVD) had been noted in each eye at the previous several examinations. Because of this finding, his risk for retinal detachment was diminished.
Refraction produced visual acuity of 20/20 in each eye. Correction was recorded as –3.25 SPH and –4.00 SPH in the right and left eye, respectively. He was comfortable removing his spectacle lenses for near work. The anterior segment of each eye was unremarkable for age. Applanation tonometry was measured at 17 mm Hg and 18 mm Hg in the right and left eye, respectively. Dilated fundus examination revealed lens changes that were considered to be age-appropriate and did not interfere subjectively with visual function for activities of daily living. Findings in the posterior segment confirmed PVD, distinct optic disc margins and healthy rim tissue, appropriate course and caliber of the retinal vasculature, and macular appearance consistent with previously observed stage 1 AMD changes.
Observation of the peripheral retina revealed LRD as illustrated in Figure 3 for the right eye, which was similar for the left eye. No other retinal abnormalities were observed in either eye. The patient was made aware of the findings and reminded of the symptoms and risks of retinal detachment. He was asked to return in 1 year or sooner if symptoms as reviewed developed, and to continue taking the daily Age-Related Eye Disease Studies (AREDS) formula. No other imaging was ordered.
Discussion
It is significant that in each of these cases the patient was asymptomatic for photopsia or entopsia (flashes, floaters). This small cluster of cases illustrates some of the known parameters of LRD. Byer has reported that the condition’s long-term course is one of stability, that LRD often presents bilaterally, and that myopia is not the exclusive associated refractive correction.2,3 We reported that in patients whose spherical-equivalent refractive correction was greater than –6.00 D, the most prevalent peripheral retinal finding was lattice. This was seen in 7 of our 30 patients (23.3%).4
In an earlier report we examined 600 consecutive primary care patients. Characteristics of this large population study included prevalence of the condition of 5.2%, absence of gender predilection, and the universal geographic location of lesions within the vertical meridians (within 1 clock hour of the 12 or 6 o’clock position).5
LRD was initially described by Rutnin and Schepens in the late 1960s.6 They characterized the observed vitreoretinal presentation as a degeneration. This was largely based on the fact that patients in their reported population were of older age. Findings from later studies suggested that LRD could appear in younger patients, as the present series illustrates.2,3,5 Data from histological studies correlating with clinical observations have now suggested that LRD is, in fact, a developmental abnormality.7,8 This has become the contemporary clinical characterization of LRD.
The significance of LRD is its association with rhegmatogenous retinal detachment (RRD). For that reason, patients who were discovered to harbor lattice lesions were recommended for prophylaxis.9 That clinical advice changed with a landmark report whose findings indicated that a proportion of patients with LRD who were treated developed retinal tears in areas remote from the treated site.10 In addition, these investigators found that patients who were observed and followed had similar visual outcomes to those who had been treated.
That LRD is a leading predisposing factor for RRD is undeniable. Recent data from several centers encompassing large numbers of patients link posterior vitreous detachment (PVD) and LRD to acute RRD.12-16 These findings and those from other studies have led to the current practice guidelines.3,10,11,17-19 Prophylactic treatment should be advised with caution, especially in asymptomatic patients. Contemporary guidelines reserve this recommendation for special cases, such as patients with a family or personal history of RD, significant myopia due to axial elongation, previous trauma, or the acute onset of symptoms, for example.17-19
Because some cases are attended to at some time after the retinal break and potential subsequent RRD occurs, it is incumbent on clinicians to examine and monitor appropriately those patients with such predisposing conditions conscientiously, which brings us to clinical examination for LRD and other predisposing conditions to RRD. Guidelines from the American Academy of Ophthalmology and the American Optometric Association recommend complete evaluation of the ocular fundus.19,20 This may include dilated fundus examination and documentation or evaluation using widefield imaging and optical coherence tomography.21,22 Both these techniques have been shown in the optimum setting to enhance examination of the peripheral ocular fundus for signs of LRD and other peripheral retinal abnormalities. Although not universally available in clinical practice, they augment current fundus examination and documentation protocols. The mainstay of fundus examination remains examination through a dilated pupil with scleral indentation as indicated.20
Among symptomatic patients with findings that are consistent with retinal break or detachment, or who have a history of LRD, time is of the essence. Prompt evaluation and adherence to guidelines for treatment recommendations are essential to the preservation of vision and sight.
