Hematological Disorders

Anemias & Ocular Signs - Pale Views

• Conjunctival pallor: Most common; check lower palpebral conjunctiva.
• Fundoscopic Changes (due to retinal hypoxia):
  • Generalized retinal pallor.
  • Retinal hemorrhages: All layers; flame-shaped (NFL), dot & blot (INL/OPL).
  • Cotton wool spots (CWS): Focal ischemia causing axoplasmic debris.
  • Roth spots: Hemorrhages with white centers (platelet-fibrin, cells).
  • Venous tortuosity and dilation.
  • Optic disc edema: Seen in severe anemia (e.g., Hb < 5-7 g/dL).
• Pernicious Anemia (B12 deficiency): May cause optic neuropathy.

⭐ In severe chronic anemia, particularly with Hb levels below 5 g/dL, bilateral retinal hemorrhages and even papilledema can occur due to a combination of hypoxia and hyperdynamic circulation.

Leukemias/Lymphomas - Eye Infiltrates

• Leukemic Retinopathy: Commonest ocular finding.
  • Features: Retinal hemorrhages (all layers), cotton wool spots, Roth spots.
  • Vascular changes: Venous dilation/tortuosity, perivascular sheathing.
  • Peripheral neovascularization (rare).
• Direct Infiltration by Leukemic Cells:
  • Orbit: Proptosis (esp. AML - chloroma/granulocytic sarcoma; childhood ALL).
  • Uvea: Iritis, pseudohypopyon (leukemic cells), diffuse choroidal infiltration (yellowish-pink).
  • Optic Nerve: Swelling, infiltration, subsequent atrophy.
• Lymphoma-Specific:
  • Primary Intraocular Lymphoma (PIOL): Often B-cell, associated with CNS lymphoma. Presents as chronic uveitis, vitritis, sub-RPE infiltrates; a masquerade syndrome.
  • Orbital Lymphoma: Typically painless proptosis in older adults.

⭐ Optic nerve infiltration in Acute Lymphoblastic Leukemia (ALL) can be an early sign of CNS relapse and carries a poor prognosis.

Hyperviscosity & Polycythemia - Thick Blood, Bad Sight

• Pathophysiology: ↑ blood viscosity (hyperviscosity syndromes like Waldenström's macroglobulinemia, multiple myeloma) or ↑ RBC mass (polycythemia vera) → impaired microcirculation.
• Ocular Features (often bilateral):
  • Retinal Veins: Dilation, tortuosity, segmentation ("sausage-link" or "boxcar" appearance).
  • Fundus: Dark red/plethoric (esp. polycythemia), retinal hemorrhages (flame, dot/blot), cotton wool spots, microaneurysms.
  • Optic Disc: Papilledema, hyperemic disc.
  • Vascular Occlusions: ↑ risk of CRVO, BRVO, CRAO.
  • Symptoms: Blurred vision, transient visual obscurations (amaurosis fugax), diplopia.
  • Anterior Segment: Conjunctival sludging, plethora, secondary glaucoma (rare).

  ⭐ "Sausage-link" appearance (fundus varicosities) of retinal veins is a classic sign of hyperviscosity retinopathy.

Bleeding & Clotting Issues - Hemorrhage Havoc

• Thrombocytopenia (platelet count < 150,000/μL):
  • Retinal hemorrhages (dot, blot, flame-shaped)
  • Subconjunctival hemorrhage
  • Roth spots (hemorrhage with white center)
  • Vitreous hemorrhage (rare)
  • Hyphema
• Disseminated Intravascular Coagulation (DIC):
  • Widespread microvascular thrombosis & secondary fibrinolysis.
  • Ocular: Similar to thrombocytopenia; choroidal infarcts, exudative retinal detachment.
  • Often bilateral, severe visual loss.

⭐ Roth spots, though non-specific, are classically associated with bacterial endocarditis but can be seen in various hematological disorders causing retinal hemorrhages, including leukemia and severe anemia.

• Other coagulopathies (e.g., Hemophilia, Von Willebrand disease):
  • Spontaneous subconjunctival hemorrhage
  • Orbital hematoma (post-trauma risk ↑)
  • Hyphema

High‑Yield Points - ⚡ Biggest Takeaways

• Sickle Cell Retinopathy: Sea-fan neovascularization is pathognomonic; also salmon-patch hemorrhages, black sunbursts.
• Leukemia: Key signs: Roth spots, retinal hemorrhages, optic nerve infiltration, sometimes proptosis.
• Severe Anemia: Presents with pale conjunctiva, retinal hemorrhages, and cotton wool spots.
• Polycythemia Vera: Features conjunctival/retinal plethora, engorged tortuous veins, and possible papilledema.
• Hyperviscosity Syndromes (Myeloma, Waldenström's): Cause retinopathy with venous tortuosity ("sausage-link" appearance), hemorrhages.
• Thrombocytopenia: Associated with subconjunctival and retinal hemorrhages.