Low Serum Ferritin as the Root Trigger, in 3D
Peripheral iron stores set the ceiling for brain iron delivery. Here the same iron-deficiency cascade plays out over a real 3D scene: an orbitable basal-ganglia core, a physical ferritin column, and an articulated leg model you can rotate and zoom around instead of a flat 2D cross-section.
- <50: Ferritin threshold (ng/mL RLS risk zone)
- 30–300: Normal range (ng/mL typical adult)
- ~25%: Prevalence link (RLS patients iron deficient)
- Serum ferritin: Screening test (first-line lab check)
Peripheral iron status
Low ferritin reflects depleted total-body iron stores; the 3D ferritin column's fill height tracks the serum ferritin slider directly.
Brain Iron Depletion in the Basal Ganglia
Regional brain iron tracks peripheral ferritin with a lag — modeled here as an adjustable first-order transport delay that drives how fast the 3D basal-ganglia core's glow and color catch up to the current ferritin level.
- Substantia nigra: Key region (iron-rich dopaminergic hub)
- MRI T2*: Imaging marker (detects regional iron loss)
- Transferrin: Transport protein (crosses blood-brain barrier)
- Reduced: CSF ferritin (in RLS patients)
Regional brain iron
Basal ganglia iron pools shrink under systemic deficiency; orbit the scene to see the core's emissive glow dim as the pool falls.
Iron-Dependent Dopamine Synthesis Falters
Iron is a cofactor for the dopamine-synthesis enzyme pathway. The orbiting particle field around the basal-ganglia core represents dopaminergic signaling — fewer particles stay active as the lagged iron pool drops.
- Tyrosine hydroxylase: Cofactor enzyme (iron-dependent step)
- Evening worsening: Circadian pattern (matches RLS symptom timing)
- D2 downregulation: Receptor change (postsynaptic adaptation)
- Dopamine agonists: Treatment clue (partially relieve symptoms)
Dopamine pathway disruption
Reduced iron impairs dopaminergic neurotransmission, visualized as the particle field thinning out in real time.
From Dysfunction to Restless Legs Sensation
Circuit imbalance produces the urge to move the legs. The 3D leg model's hip, knee and ankle joints twitch with an amplitude driven directly by the computed RLS severity score, with expanding pulse rings at the foot.
- Urge to move: Core symptom (worse at rest, evening)
- Movement relieves: Relief pattern (temporary symptom relief)
- Frequent: Sleep disruption (periodic limb movements)
- Clinical criteria: Diagnosis basis (IRLSSG four-point checklist)
Symptom expression
Restlessness pulses correlate with dopaminergic deficit severity — rotate the camera to watch the joint twitch and pulse rings from any angle.
Symptom Improvement with Iron Repletion
Restoring ferritin gradually restores basal ganglia function. The 3D improvement track's bar length grows with weeks of iron therapy, exactly matching the severity reduction formula from the 2D original.
- Oral/IV iron: Therapy route (depends on severity)
- Weeks: Response time (gradual symptom easing)
- >75: Target ferritin (ng/mL treatment goal)
- Reduced severity: Outcome (in responders)
Therapeutic response
Iron therapy over weeks lowers RLS severity scores, shown live as the leg twitch amplitude and pulse-ring intensity fade.
Sustained iron repletion improves sleep and symptom scores.