Optic pit is a rare disorder, occurring in one in 11,000 people. Currently, the treatment of choice of optic-pit–associated maculopathy is pars plana vitrectomy. Thus, it is unusual to present the natural course of this disease in spectral-domain optical coherence tomography (SD-OCT, Copernicus, Optopol, Zawiercie, Poland; distributed by Canon Europe). Here we present a report of a 17-year old girl who refused surgery for many years but who continued to attend followup visits.
PRESENTATION
This patient presented with (Snellen) visual acuities
of 0.8 in the eye with an optic nerve pit and 1.0 in the
fellow eye. Fundus examination revealed a unilateral
cavitary optic disc anomaly and an associated serous
macular detachment. At that time, SD-OCT showed
the presence of retinoschisis in the macular area.
Striae of retinal tissue could be seen between the
outer plexiform layer and the outer nuclear layer
(Figure 1A). The macula was elevated to 678 µm central
retinal thickness (CRT). Because of good visual
acuity the patient refused surgery.
SD-OCT FINDINGS IN NATURAL HISTORY
After 2 years of stabilization, visual acuity suddenly
dropped to 0.3. SD-OCT revealed additional photoreceptor
detachment in the center of the fovea. CRT was
890 μm (Figure 1B). Two months later, visual acuity
improved to 0.4, and SD-OCT showed a slight decrease
in the macular elevation to 683 µm CRT. In SD-OCT
scans we observed a further elevation of the photoreceptor
layer. Moreover, a new connection between the
photoreceptor layer and the outer nuclear layer was observed (Figure 1C).
The visual acuity was stable for the next year, and then the schisis spontaneously slightly resolved and the fovea was elevated to only 230 µm. Cystoidal spaces in the outer retinal layers were noted, and additionally an interconnection between the cystoid space and the subretinal layer was noted. The patient continued to refuse surgery. On SD-OCT images of the optic disc, a membrane on the bottom of the disc was noted (Figure 2).
DISCUSSION
Macular detachment is frequent in optic pit maculopathy.
Based on the case presented above, we propose that a schisis-like elevation
is the first step in the process of
total macular detachment. The
tissue-forming striae between
the outer nuclear segments and
photoreceptor layer tend to
shorten and further to detach
the photoreceptor layer.
Another interesting issue in this
case is the vision improvement
after the photoreceptors
detached from the pigment
epithelium and approached
other detached retinal layers.
Additionally, there was a membrane
on the bottom of the
optic disc, which in our opinion,
is notable. Doyle and coworkers1
also observed this membrane in
three of eight cases presented in
their SD-OCT documented
study. The authors suggest that
the membrane may represent a
barrier to the passage of fluid
into or under the retina, consisting
of neuroectodermal and
astroglial tissue. It was also suggested
that an intact membrane
protects against maculopathy
because in all three presented cases maculopathy did
not coexist. In the case we present, although on the
central scan the membrane is intact, there are disruptions
in other B-scans in the 3-D imaging mode.
To conclude, SD-OCT enables the clinician to spot subtle changes in the macula during the natural course of optic-pit–associated maculopathy. Additionally, 3-D optic disc imaging is possible.
Michalewska Zofia, MD, PhD; Michalewski Janusz, MD, PhD; and Professor Nawrocki Jerzy are with Klinika Okulistyczna „Jasne Blonia” in Lodz, Poland. The authors report no relevant financial relationships. They can be reached at +48 42 6368282; fax: +48 42 6110505. Dr. Michalewska can be reached via email at zosia_n@yahoo.com; Dr. Michalewski can be reached via e-mail at shadowell@wp.pl; and Prof. Nawrocki can be reached via e-mail at jerzy_n@poczta.onet.pl.
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