[Verse 1] Cerebrospinal fluid, choroid plexus weaves it slow Five hundred mils a day, Monro to aqueduct it flows Obstructive means the pathway's closed — a clot, a tumour, scarred-up ependyme Communicating means absorption fails, the villi can't reclaim Aqueductal stenosis, L1CAM on the X Dandy-Walker, Chiari Two, myelomeningocele complex Post-haemorrhagic, post-infective, tumour pressing hard Ex vacuo is atrophy — not hydrocephalus, discard [Chorus] Macrocephaly, sunsetting eyes — that's your infant on the ward Headache, papilledema — paediatric, can't be ignored Gait and cognition, wet and slow — iNPH in the hall Diagnose the mechanism, choose the diversion, catch them all [Verse 2] Kocher's point for proximal tip — two centimetres back From coronal suture, mid-pupillary, ride the track Keen's and Frazier's, Dandy's too — posterior approaches known Aim the catheter clear of plexus, let the ventricle breathe alone Differential pressure, programmable, flow-regulated, gravitational weight Antisiphon device prevents the siphon overdrainage fate Distal site — the peritoneum's first, then atrial, pleural spare Antibiotic-impregnated catheters, bundles, minimal hands in there [Chorus] Macrocephaly, sunsetting eyes — that's your infant on the ward Headache, papilledema — paediatric, can't be ignored Gait and cognition, wet and slow — iNPH in the hall Diagnose the mechanism, choose the diversion, catch them all [Verse 3] Shunt malfunction — proximal blocked with choroid tangled in Or the valve is calcified, or the distal tip's migrated thin Infection shows in weeks, Staph epidermidis leads the count Externalize, sterilize the CSF, then reimplant the mount Overdrainage carves the slit ventricle syndrome deep Subdural collections pooling while the patient cannot sleep Run your shunt series — skull, chest, abdomen, plain films sequential read Normal-sized ventricles don't exclude — compliance shifts concede [Bridge] Endoscopic third ventriculostomy — floor of the third, the fenestration's made Mammillary bodies, basilar artery — margins where you're afraid ETV success score guides you — age and aetiology scored Infants fare better paired with choroid plexus cauterized aboard African data changed the calculus — Uganda's cohorts proved the case Late closure fails silently, watch those patients, leave no trace [Verse 4] External ventricular drain — Kocher's point, bolt it true Zero to the tragus, set the column, titrate fluid through Wean by raising the level slow, clamp and watch the pressure trend Infection climbs past five days — swap the drain before it bends Lumbar drains for CSF fistulae, idiopathic pressure too But herniation waits if obstruction's missed — the stakes accrue So image first, exclude the block, then let the needle in below One wrong step at lumbar level sends the brainstem down below
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