OcuLearning › Retina

Optic Pit

CHRONIC — Retina

Symptoms

  • often asymptomatic; incidental finding on routine exam
  • painless central blur or metamorphopsia (if maculopathy develops)
  • central or paracentral scotoma
  • micropsia (objects appearing smaller)

Clinical Findings

Optic disc morphology

  • hallmark: small, round/oval, grayish depression within the optic nerve head
  • location: typically inferotemporal (~70%); may be central
  • associated peripapillary chorioretinal atrophy crescent
  • glial membrane may drape over the pit

Optic pit maculopathy

  • occurs in 25–75% of cases, usually in the 2nd–4th decade of life
  • inner-retinal schisis-like splitting between the pit and macula
  • outer-layer serous macular detachment
  • hyporeflective communicating channel between pit and retina on oct

Visual fields

  • enlarged blind spot and arcuate defects corresponding to the pit

Etiology

Pathophysiology

  • congenital defect of the optic nerve head involving focal excavation
  • fluid source for maculopathy is debated (vitreous, csf, or nerve parenchyma)
  • communication channel allows fluid to track from the pit to the retinal layers

Genetics

  • usually unilateral and sporadic; rarely bilateral

Red Flags

  • optic pit maculopathy is frequently misdiagnosed as central serous chorioretinopathy (csc)
  • bilateral pits or associated midline anomalies mandate mri to rule out basal encephalocele
  • sudden vision drop: fluid tracking from the disc to the fovea

Investigations

Imaging (mandatory)

  • oct: differentiates from csc; shows pathognomonic inner-retinal schisis and a connection to the disc
  • fluorescein angiography (fa): shows late staining of the pit; lacks the "smokestack" leak of csc

Systemic workup

  • neuroimaging (mri brain/orbits): required for bilateral cases or if morning glory disc is present

Functional testing

  • amsler grid and humphrey visual field (hvf)

Treatment

Conservative

  • observation for asymptomatic pits; many remain stable for life

Surgical (definitive)

  • pars plana vitrectomy (ppv) with ilm peeling and gas tamponade (sf6 or c3f8)
  • face-down positioning required post-operatively
  • note: laser photocoagulation at the temporal disc margin is an older, less reliable adjunct

Visual prognosis

  • anatomic closure is successful in ~70–80%; visual recovery is slow (months to years)

Clinical Pearl

an optic pit with serous macular detachment is often confused with csc — oct reveals retinoschisis-like splitting and a communicating channel to the pit, and vitrectomy is the definitive treatment.

Differential Diagnosis

  • • central serous chorioretinopathy (csc) — lacking the disc connection
  • • acquired pit of the optic nerve (glaucomatous damage)
  • • optic disc coloboma
  • • morning glory disc anomaly

Related Retina Conditions