Absence of septum pellucidum


Absence of septum pellucidum (medical condition) is the absence of the thin membrane that separates the two halves of the brain. The defect itself is not a disorder but is usually observed as a characteristic of a condition called septo-optic dysplasia which also involves optic nerve and pituitary abnormalities.


  • Blindness
  • Reduced vision
  • Nystagmus
  • Dilated pupils in light
  • Inward deviation of eyes
  • Outward deviation of eyes
  • Hormonal problems
  • Low muscle tone
  • Seizures
  • Jaundice
  • Impaired intelligence
  • Mental retardation
  • Learning disabilities
  • Neurological problems
  • Developmental delay


  • Transient vision loss (24 hours: Sudden, painless Retinal artery or vein occlusion
  • Ischemic optic neuropathy (must rule out giant cell/temporal arteritis to prevent permanent bilateral vision loss)
  • Vitreous or aqueous hemorrhage (hyphema)
  • Retinal detachment
  • Other retinal or CNS disease (e.g., cortical blindness due to occipital lobe CVA)
  • Exposure (“Welder's flash”) or prolonged exposure to intense sunlight # Vision loss >24 hours: Gradual, painless Cataract # Refractive error # Open angle glaucoma # Chronic retinopathy (e.g., age-related macular degeneration, diabetic retinopathy) # Chronic corneal disease (e.g., corneal dystrophy) # Optic neuropathy/atrophy (e.g., compressive lesion, toxic-metabolic cause, dominant optic neuropathy, radiation) # Retinitis pigmentosa # Pseudotumor cerebri # Vision loss >24 hours: Painful Acute angle closure glaucoma # Optic neuritis (pain with extraocular motion) # Orbital apex/superior orbital fissure/ cavernous sinus syndrome # Uveitis # Corneal hydrops (keratoconus)
  • Ocular onchocerciasis (“river blindness”) –Common cause of blindness in developing nations due to Onchocerca volvulus worm
  • Corneal abrasion or ulcer
  • Herpes simplex or zoster infection


The absence of the septum pellucidum alone is not a disorder. However, when it is part of septo-optic dysplasia the prognosis varies according to the presence and severity of associated symptoms.


Absence of the septum pellucidum alone is not a disorder but is instead a characteristic noted in children with septo-optic dysplasia.

  • Treat underlying causes (e.g., brain tumor, carotid stenosis, cardiac valvular vegetations, hypotension)
  •  Temporal arteritis: Systemic steroids
  • Nonarteritic ischemic optic neuropathy: Aspirin
  • Optic neuritis: Systemic steroids
  • Glaucoma: Topical antiglaucoma medications; peripheral iridotomy for angle closure
  • Retinal detachment: Surgical repair
  • Cataracts: Surgical removal
  • AV fistula: Embolize
  • Cavernous sinus thrombosis: Antibiotics, anticoagulation
  • Mucormycosis: Amphotericin B, debridement
  • Pituitary apoplexy: Systemic steroids, neurosurgical intervention
  • Herpes zoster: Systemic acyclovir
  • Tolosa-Hunt: Systemic steroid
  • Keratoconus/corneal hydrops: Cycloplegic, hypertonic (5%) NaCl ointment, corneal transplant