Challenges in Optic Disc Pit Maculopathy Treatment Many techniques have been described; choose the best one for the individual patient. BY BARBARA PAROLINI, MD; AND MICHELE PALMIERI, MD ptic disc pit (ODP) is a rare congenital abnormality ODP MACULOPATHY of the optic nerve head, first described by Wiethe in ODP is usually asymptomatic, but a percentage of affected 1882.1 ODP usually appears as a grayish-whitish, round patients (25%-75% depending on the report) may develop a or oval depression of the optic disc (Figure 1A), and it macular serous detachment or a retinoschisis-like maculopa- may have different levels of severity. It is a spectrum of thy due to the presence, respectively, of subretinal or intra- Ocongenital cavitary anomalies of the optic disc, ranging from retinal fluid.3,6,9 This condition, known as ODP maculopathy the more common optic pit to the so-called morning glory (ODPM), causes visual impairment, especially in long-stand- syndrome (Figure 1B) to coloboma not only of the optic ing cases, in which lamellar or full-thickness macular holes nerve but also of the choroid (Figure 1C). It is also found in and retinal pigment epithelium atrophy may appear.10-12 the papillorenal syndrome determined by a mutation of the The exact mechanism of the pathophysiology of ODPM PAX2 gene. and the origin of the fluid remain unclear. It has been pro- ODP is bilateral in 15% of cases (Figure 2) and occurs posed that vitreous or cerebrospinal fluid (CSF) may be the equally in men and women with an estimated incidence of origin of the fluid responsible for ODPM.13-15 In the first case, 1 to 2 per 10,000 people.2-5 The most frequent location is in it is posited that the vitreous exerts traction on the macula the temporal segment of the disc, but ODP has also been and optic disc, leading to negative pressure and the subse- described on the nasal side.3,6 quent entrance of fluid through the ODP into the submacu- Histopathologically, ODP appears as a herniation of dys- lar space.14,15 In the second case, the supposition is that the plastic retinal tissue into a collagen-rich excavation that can CSF flows through direct communication between the mac- extend into the subarachnoid space through a defect in the ular subretinal space and subarachnoid space through the lamina cribrosa (Figure 3).7 Studies of ODP using OCT have ODP defect.10,16,17 This hypothesis was supported by Ohno- revealed connections between the subretinal and intraretinal Matsui et al,18 who imaged the subarachnoid space just pos- space, the perineural space, and the vitreous cavity (Figure 4).8 terior to the bottom of the ODP using swept-source OCT. A B C Figure 1. ODP usually appears as a grayish-whitish, round or oval depression of the optic disc (A). ODP ranges from optic pit to so-called morning glory syndrome (B) to coloboma of the optic nerve and choroid (C). JULY/AUGUST 2019 | RETINA TODAY 33 s RARE AND INHERITED DISEASES A B RETINA TODAY ON THE ROAD This article is adapted from a lecture the author presented at the Duke Advanced Vitreous Surgery Course in April. The 2020 meeting will be held April 17-18, 2020, in Durham, North Carolina. Visit MedConfs.com for details. Figure 2. ODP is bilateral in 15% of cases. Retinography of the right (A) and left (B) eye of an 8-year-old boy with bilateral coloboma of the optic nerve and involving a large area of the central inferior and nasal choroid. Moreover, in eyes with ODPM, communication between the vitreous cavity, the subarachnoid space, and the subretinal space was confirmed by the observation of gas and silicone oil migration into the subretinal and intracranial space, respectively, after pars plana vitrectomy (PPV).19,20 In most cases, the fluid follows the pattern described by Lincoff et al,21 in which fluid from the ODP first creates a schisis-like separation of the inner retina and then reaches the subretinal space, creating a macular neuroepithelial detachment. Spontaneous reabsorp- tion of fluid is possible in up to 25% of cases according to Gass,22 but relapses are frequent, leading to a progressive deterioration of the macular structures and visual loss. This recurrent trend of ODPM may be explained by the pulsat- ing dynamics of intracranial pressure.23 Figure 3. ODP appears as a herniation of dysplastic retinal tissue into a collagen-rich excavation that can extend into TREATMENT OF ODPM the subarachnoid space through a defect in the lamina cribrosa. Several treatment alternatives have been proposed for ODPM, including conservative management, laser pho- tocoagulation, macular buckling sur- gery, gas tamponade, partial thickness retinotomy,24 and removal of glial tis- sue at the temporal wall of the ODP.25 Another therapeutic approach to ODPM is pneumatic displacement with intravitreal gas tamponade alone or combined with laser.21,26,27 Gas tamponade may induce a posterior Figure 4. OCT imaging in ODP can reveal connections between the subretinal and intraretinal space, the perineural vitreous detachment, thereby reduc- space, and the vitreous cavity. ing vitreomacular traction, whereas 34 RETINA TODAY | JULY/AUGUST 2019 s RARE AND INHERITED DISEASES A B explanation regarding the efficacy of PPV is needed.41 In these cases, the key step for a successful surgery maybe the sealing of the pit. Several authors have also described stuffing the ODP with materials, including an ILM flap,42-44 an ILM flap and fibrin glue,45 the fibrin seal- ant Evicel (Johnson & Johnson),46 or autologous fibrin.47-49 Additionally, using an inverted ILM flap technique to cover the optic disc, including the Figure 5. OCT of the left eye of the patient depicted in Figure 2. The horizontal scan of the OCT (A) shows the depth ODP but excluding the foveal area, of the coloboma. Identification of the fovea can be challenging in cases of ODP and is not possible in this particular has shown promising results.50,51 case because it is located inside the coloboma. A mild amount of subretinal fluid is visible. The color photo (B) We have applied this technique to shows the extensive coloboma and the level of the OCT scan in the extramacular temporal areas shown below. five patients in the past 5 years when laser photocoagulation contributes (ILM) peeling. Multiple studies have pneumatic displacement did not to sealing of the pit.28 This simple and reported high anatomic success rate resolve the pathology. Reabsorption minimally invasive technique has been (50%-95%) and good functional out- of subretinal fluid might take a few reported to have a good success rate, comes with PPV, with VA improve- months, even in cases in which the although more than one injection is ment in more than 50% of cases.27-42 ILM flap is visible in the pit on post- often necessary.26,28 Inducing a posterior vitreous operative OCT (Figure 5). We have tried this technique in detachment with PPV can relieve the Macular buckling is another 15 eyes with good initial outcomes. In traction exerted by the vitreous on alternative for treatment of ODPM. some of these eyes we have observed the macula, facilitating the absorption Theodossiadis et al first described a relapse. However, in patients young- of the subretinal fluid. The application this technique and reported a suc- er than 20 years we still consider it of laser at the edge of the pit helps to cess rate of about 85%.30,41,52-54 The preferable to apply this technique seal it, obstructing the communica- macular buckle pushes the macular first. It can then be repeated years tion between the ODP and the retina. surface toward the vitreous chamber, later in the event of relapse, leav- However, the need for laser has not obstructing the entrance of fluid and ing the option of vitrectomy if this been definitively demonstrated. alleviating vitreous traction. treatment fails. If the vitreous cavity is the source Macular buckling is considered Today, PPV is often the treatment of fluid in ODPM, then the role by many a difficult technique and of choice,26,29,30 either alone or com- played by PPV as an effective treat- for this reason is not widely applied. bined with gas tamponade and/or ment is comprehensible. On the other However, surgeons should have many laser photocoagulation and with or hand, if the subretinal fluid originates weapons in their arsenals so that they without internal limiting membrane from the subarachnoid space, further can choose the best one based on the needs of the individual patient. AT A GLANCE CASE REPORT Here, we share the case report s Optic disc pit (ODP) is a spectrum of congenital cavitary anomalies of the of an 8-year-old boy with bilateral optic disc, ranging from optic pit to morning glory syndrome to coloboma coloboma of the optic nerve and the central inferior choroid, as well as the not only of the optic nerve but also of the choroid. Up to 75% of patients with inferior iris as an associated finding ODP may develop ODP maculopathy. (Figures 2 and 5). The patient first s developed a macular detachment in ODP maculopathy can cause visual impairment, especially in long-standing the left eye, which quickly developed cases. into a complete retinal detachment caused by fluid coming from the ODP s In a case report, the author describes a challenging repair of an ODP in a and a suspected macular hole. young patient. This case presented several chal- lenges, including that the macular 36 RETINA TODAY | JULY/AUGUST 2019 s RARE AND INHERITED DISEASES s 5.