Traumatic macular hole: Clinical aspects and controversies

INTRODUCTION

Ocular blunt trauma, among multiple injuries, may cause the macular hole, resulting in loss of vision. The first description was made by Knapp,^[1] in 1869, in a young patient who suffered an eye traumatism. Noyes,^[2] 2 years later, ophthalmoscopically recognized the lesion as a complete thickness defect in the center of the macula and postulated as a cause of its formation the mechanical energy created by the movement in waves of the vitreous fluid originated by the effect of blow and blow of blunt trauma. Fuchs^[3] and Coats,^[4] in 1901, made the first histopathological description of the lesion, noting the presence of intraretinal cysts that could form the macular hole when coalescing. Schepens, in 1955, postulated the role of the prefoveolar vitreous cortex in the genesis of the defect.

EPIDEMIOLOGY

The incidence of the traumatic macular hole varies in the literature between 1% and 9%.^[5,6] Patients are generally young between the second and third decades of life and more often, male [Table 1].^[7-13]

The traumatic macular hole is produced mainly by blunt ocular traumatism, being originated by balls in general of a small diameter such as tennis, squash, and handball. Other less frequent causes are blows with kicks or fists.^[14] Moreover, we have to mention traumatisms produced by industrial laser^[15] or iatrogenically by the use of high energies in the application of Nd:YAG laser.^[16] The production of a macular hole due to penetrating or perforating trauma is exceptional.

PHYSIOLOGY

The pathogenesis of macular hole formation after blunt trauma is today controversial. They generally appear immediately after the injury, nevertheless in some cases can occur weeks later.

The main hypotheses considered are as follows:

1. The resulting retinal stretch, either from the deformation of the eyeball or the force of the impact on the pole posterior to the moment of the trauma, could cause the macular rupture^[12]

2. The cystic macular degeneration due to direct injury would generate in later time the formation of the hole

3. The detachment of the posterior vitreous due to trauma could cause macular dehiscence.

Gass^[17] proposes that the mechanisms by which the blunt trauma causes the macular hole can be one or the combination of:

1. Necrosis and post-contusional cystoid degeneration

2. Subfoveal hemorrhage caused by a choroidal rupture

3. Anterior-posterior vitreous traction.

We must consider the different genesis in cases of macular holes produced iatrogenically by the application of Nd:YAG laser with high energies that have a different pathogenesis. It is postulated that the Nd:YAG laser produces a thermomechanical disruption. After the application, a rapid expansion of plasma that produces cavitation in the form of a bubble immediately begins with the shock wave, leading to the dissolution of the retinal tissue with the consequent formation of the macular hole.^[12,13]

CLINICAL ASPECTS

Patients with a traumatic macular hole present a vision that commonly ranges between 20/80 and 20/400. Biomicroscopy of the posterior segment typically shows a full-thickness defect of the neurosensory retina at the fovea, usually elliptical and with irregular edges as opposed to idiopathic macular holes, which is generally round in shape and regular edges.^[14] They present an average size of between 0.2 and 0.5 diameters of the optic disc. In 5% of cases, we can see a free operculum and in 10% a retinal detachment around the hole. The posterior vitreous remains completely adhered in 85% of the cases, partially adhered in 15%, it is rare to find a total posterior vitreous detachment.^[12] We can observe yellowish deposits at the base of the hole. The finding of an epiretinal membrane is infrequent [Figure 1a], which, if present, is late onset.^[18]

Close

Figure 1:

(a) Retinography presenting a traumatic macular hole and an epiretinal membrane. (b) Retinography shows choroidal rupture, subretinal hemorrhage, and a macular hole. A 20-year-old male patient presenting decreased vision in the right eye secondary to trauma with a ball.

Export to PPT

When dealing with blunt ocular trauma of a complex entity, we can often find the following associations in both the anterior and/or posterior segments: Vitreous hemorrhage, hyphema, chorioretinal atrophy, choroidal ruptures, angular recessions, retinal tears, retinal dialysis, and retinal detachment [Figure 1b].

COMPLEMENTARY EXAMINATIONS

Principally, two complementary tests are used to help in the diagnosis of traumatic macular hole: Retinal fluorescein angiography and optical coherence tomography (OCT).

The retinal fluorescein angiography typically shows a central hyperfluorescence by window effect corresponding to the base of the macular hole, a hyperfluorescence around the hole corresponding to subretinal fluid, you can also find deposits at the base of the hole that is hypofluorescent [Figures 2 and 3].

Close

Figure 2:

(a and b) Retinal Fluorescein Angiography showing central hyperfluorescence by window effect that corresponds to the hole with a decreased signal in the edges by the subretinal liquid, and vertical arcuate hyperfluorescence corresponding to choroidal rupture.

Export to PPT

Close

Figure 3:

(a-c) Retinal Fluorescein Angiography showing two traumatic macular holes in the same eye.

Export to PPT

The OCT shows complete retinal thickness loss at the foveal level with an abrupt slope between the steep edges of the hole and the pigmentary epithelium; the presence of operculum; cystic retinal changes; presence of an epiretinal membrane; and presence of abnormalities in the surrounding retina [Figure 4a and b].^[19] OCT is currently an essential study.

Close

Figure 4:

(a and b) Optical coherence tomography (OCT) showing a complete retinal thickness defect, intra-retinal cysts at the edges of the hole and subretinal fluid.

Export to PPT

TREATMENT

The treatment of the traumatic macular hole is controversial. On the one hand, observation can be considered because there is a chance of spontaneous closure. It has been found in cases with small diameter holes (0.1–0.2 diameters of the optic disc), without detachment of the posterior vitreous, or presence of epiretinal membrane.^[5,20-22] The spontaneous closure has been described in some series up to 40% of the cases, after 2 months or more of the injury,^[5,20-24] until 66.7% after 6 months.^[25]

On the other hand, surgery realizing a pars plana vitrectomy has excellent closure results, with mechanical creation of a posterior vitreous detachment, expandable gas exchange C3F8 or SF6 at different concentrations, and post-operative positioning in a prone position for a period of given time.^[7,8,10] The peeling of the internal limiting membrane and the extraction of the epiretinal membrane, in case of being present, are other factors to consider. The anatomical closure of the hole occurs between 92% and 96% of cases [Figure 5].^{[7,8,10,11,20]}

Close

Figure 5:

(a) Post-surgical retinography showing anatomical closure of the macular hole; (b) Correlation with OCT confirming the anatomical closure.

Export to PPT

Some authors describe the use of substances (transforming growth factor-beta 2, platelet concentrate, and serum) as an adjuvant to achieve hole closure.^[5,10,11] It was not shown that the use of these substances improved the effectiveness of vitrectomy in terms of anatomical results as opposed to non- use [Table 2].^{[7,8,10,11,20]}

The giant traumatic macular holes can benefit from large inverted internal limiting peeling and retinal transplantation.^[26,27]

Among the complications of surgery are retinal hemorrhages, retinal detachment [Figure 6], and visual defects, cataract formation is not typical, contrary to what happens in idiopathic macular hole surgery where it is a common complication.

Close

Figure 6:

Retinography showing a post-surgical traumatic macular hole presenting as a complication a retinal detachment.

Export to PPT

PROGNOSIS

The visual acuity at presentation varies from 20/30 to 20/400, depending on the retinal affection: Retinal detachment, vitreous hemorrhage, retinal hemorrhage, choroidal rupture, or retinal pigment epithelium damage.

The post-surgical prognosis is favorable. Patients experience an improvement in their visual acuity of two or more lines of vision between 69% and 93%. Almost 50% of patients present a visual acuity of 20/40 or better after surgical treatment [Table 3].^[7-11]

The patients in whom the spontaneous closure of the hole occurred followed the same evolution of their visual acuity as those treated by surgery.^[24,28]

The time interval from injury to surgery was statistically associated significantly with the level of visual acuity improvement.^[24,28] The different tomographic macular hole presentations has not shown a clear prognosis relation,^[25,29] but cystic edema on the edge of the hole may be an unfavorable factor for the spontaneous closure of TMH.^[25]

CONCLUSIONS

The traumatic macular hole is a rare pathology; its pathogenesis is currently controversial. The OCT is the auxiliary diagnostic method most used for its high resolution and innocuousness for the patient. The most widely used treatment is vitrectomy with an expandable liquid–gas exchange. Nevertheless, observation can be considered in patients ≤24 years of age with macular hole sizes of ≤0.2 optic disc diameter, without detachment of the posterior vitreous or epiretinal membrane, because they are more likely to achieve spontaneous closure of the hole.