1. Extra case 1

2.  22 year old female  PC: 2/52 headache  HPC: daily throbbing headache involving entire head  Worse upon waking, get better as day goes on  Has nausea, vomiting and intermittent diplopia (2/7)  Some alleviation by paracetamol and ibuprofen  PMHx: asthma  Meds: COCP  Allergies: sulphurs  FHx: An aunt died of a brain tumour in her 50s  SHx: Receptionist, shares a flat with friend

3.  O/E: Afebrile, BP 110/70, PR 80 reg  Neck supple, no meningismus  CVS/ RESP/ABDO: normal  Neuro: alert, uncomfortable from pain  Cranial nerves: pupils reactive, bilateral papilloedema, right sixth nerve palsy.  Motor Examination: normal strength  Reflexes: Normal, plantar response down going bilaterally. Normal co-ordination and gait.

4.  = swelling of the optic disc due to raised intracranial pressure  Intracranial mass lesions (eg. tumour, hematoma)  Cerebral oedema (eg. Due to acute hypoxic ischemic encephalopathy, large cerebral infarction, severe traumatic brain injury)  Increased CSF production (eg. choroid plexus papilloma)  Decreased CSF absorption (eg. arachnoid granulation adhesions after bacterial meningitis)  Obstructive hydrocephalus  Obstruction of venous outflow (eg. venous sinus thrombosis, jugular vein compression, neck surgery)  Idiopathic intracranial hypertension (pseudotumor cerebri)

5.  Idiopathic (benign) intracranial hypertension  Migraine; tension-type headache; medication overuse headache  but these would not have papilloedema  Malignant hypertension  optic neuropathy can be mistaken for papilloedema  Secondary intracranial hypertension  Metastatic tumour, hematoma  intracranial mass lesion  Acute hypoxic ischemic encephalopathy, large cerebral infarction, severe traumatic brain injury  cerebral oedema  Choroid plexus papilloma  inc CSF production  Arachnoid granulation adhesions after bacterial meningitis  dec CSF absorption  Obstructive hydrocephalus  Venous sinus thrombosis, jugular vein compression, neck surgery  obstruction of venous outflow

6.  Neuroimaging then lumbar puncture (to rule out other Dx and determine opening pressure)  MRI > CT  if IIH, MRI may show  Flattening of the posterior sclera (80%)  Distension of perioptic subarachnoid space (50%)  Enhancement (with gadolinium) of the prelaminar optic nerve (45%)  Empty sella (70%)  Intraocular protrusion of the prelaminar optic nerve (30%)  Vertical tortuosity of the orbital optic nerve (40%)  MRV is more sensitive than MRI for finding cerebral venous thromboses  LP: measure opening pressure; analyse CSF for cell count, glucose and protein  may indicate need for culture for microbial agents; CSF cytology or; antigen testing (eg, CSF VDRL)  Also need to check visual fields (assess severity and monitor response)  either Goldmann kinetic perimetry or computer-assisted static perimetry  May find: enlarged blind spot; generalized constriction; inferonasal vision loss

7.  Intermittent diplopia  believed to be due to fluctuations in perfusion of the nerve head  Papilloedema: inc ICP  transmitted to the optic nerve sheath  mechanical disruption of axoplasmic flow  swelling of the axons and leakage of water/protein/other cellular contents into the extracellular space of the optic disc  optic disc oedema  CNVI palsy  due to inc ICP; CNVI has long intracranial course before exiting the skull

8.  Contrast-enhanced MRI of the brain  normal  LP  30mL CSF drained  Lumbar puncture:   Headache improves considerably  Nausea and vomiting resolve over 1-2/7  Diplopia resolves over 1/52

10.  Lateral recumbent position (or sitting upright)  for accurate measurement of opening pressure  Level of entry for spinal needle: use highest points of iliac crests as guide for L4 vertebral body  palpate spinous processes and interspaces of L3, L4 and L5  insert needle into subarachnoid space at L3/4 or L4/5 interspace  below the termination of the spinal cord  Pt must be in foetal position  neck, back and limbs in flexion; lower lumbar spine flexed  determines success of obtaining CSF  Clean and disinfect skin  local anaesthetic for lumbar intervertebral space  insert 20 or 22 gauge spinal needle with a stylet  advance needle slowly, angling slightly towards head (aim for umbilicus)  transiently remove stylet at subarachnoid space to confirm CSF flow  pt should slowly straighten legs (allow CSF flow)  measure opening pressure with manometer  collect fluid (usually 8-15mL, but can be up to 40mL for culture)  replace stylet  remove spinal needle  Queckenstedt manoeuvre: measure CSF pressure then manually compress both jugular veins and note change in pressure  old method to show flow from ventricles to lumbar space  http://www.youtube.com/watch?v=R2_0gOI8uV0 http://www.youtube.com/watch?v=R2_0gOI8uV0

11.  Indications: diagnosis of CNS infections and sometime to help diagnose subarachnoid haemorrhage, CNS malignancies, demyelinating diseaes and Guillain-Barre syndrome  Urgent LP for suspected CNS infection (except for brain abscess or a parameningeal process) and suspected subarachnoid haemorrhage with a negative CT scan  Nonurgent LP is indicated for diagnosis of: IIH, carcinomatous meningitis, tuberculous meningitis, normal pressure hydrocephalus, CNS syphilis, CNS vasculitis  LP in therapy: spinal anaesthesia; intrathecal chemotherapy/antibiotic administration; injection of contrast media for myelography/cisternography  Contraindications: no absolute contraindications, but take care with  Possible raised intracranial pressure  Thrombocytopenia or other bleeding diathesis (including anticoagulant therapy)  Suspected spinal epidural abscess

12.  Complications: post-LP headache; infection; bleeding; cerebral herniation; minor neurologic symptoms (radicular pain, numbness); late onset of epidermoid tumours of the thecal sac; back pain  Post-LP headache: due to leakage of CSF from dura and traction on pain-sensitive structures  Infection: either meningitis or other (discitis or vertebral osteomyelitis)  but uncommon  Back pain and/or neurologic symptoms: can suggest haematoma  take care if bleeding disorder  Cerebral herniation:  take care if suspected inc ICP  Epidermoid tumour: rare, may only be evident years after procedure is performed  can be due to epidermoid tissue being transplanted into the spinal canal when not using a stylet or if the stylet is poorly fitting  CNVI palsy: results from intracranial hypotension, generally accompanied by other features of post-LP headache

13.  Opening pressure: 50–200 mm H 2 O CSF  Colour: colourless  Turbidity: crystal clear  Mononuclear cells: <5 per mm 3  Polymorphonuclear leukocytes: 0  Mean total protein: 22–38 mg/dl  Range: 9–58 mg/dl (mean ± 2.0 SD)  Glucose: 60–80% of blood glucose

14.  Opening pressure – pressures over 180 are considered abnormal  Can compare opening and closing pressure to estimate the volume of CSF reservoir.  Clarity - pleocytosis (inc cell count) is the usual reason for cloudy fluid.  >200 white cells per cubic millimeter can be present without altering the clarity  >500 white cells per cubic millimeter usually produces cloudiness.  Red cell concentrations between 500 and 6000 per mm 3 can cause the fluid to appear cloudy; concentrations of over 6000 give a grossly bloody appearance.  A markedly elevated protein can also alter the clarity of the CSF.  But little clinical use as a large number of cells can be present without affecting the clarity.  Colour - Xanthochromia commonly indicates spontaneous subarachnoid hemorrhage. A variety of conditions, however, can also produce xanthochromia: a traumatic tap; bilirubin due to jaundice; protein; etc.  Cells – CNS infections produce 3 basic CSF types which suggest diagnoses

15.  Affects the brain, appears to be (but is not) a tumour; often reversible.  Clinical criteria: include headache, papilloedema, vision loss, elevated ICP with normal cerebrospinal fluid composition, and no other cause of intracranial hypertension evident on neuroimaging or other evaluations.  Despite its prior name (BIH), it is not a benign disorder. Many patients suffer from intractable, disabling headaches, and there is a risk of severe, permanent vision loss.  Pathogenesis is unknown.  Associated conditions:  Medication – may just be anecdotal  Systemic illnesses — In addition to obesity, systemic illnesses reportedly associated with IIH include:  Addison disease  Hypoparathyroidism  Anaemia, usually severe  Sleep apnoea  Systemic lupus erythematosus (SLE)  Behcet's syndrome  Polycystic ovary syndrome  Coagulation disorders  Uremia

16.  The treatment of IIH has two major goals: the alleviation of symptoms (usually headache) and the preservation of vision.  Weight loss – low sodium wt reduction program  Medications - carbonic anhydrase inhibitors, loop diuretics, and corticosteroids  Carbonic anhydrase inhibitors – believed to reduce rate of CSF production  Cautious with corticosteroids because of weight gain, steroid withdrawal may cause severe rebound intracranial hypertension  Headache prophylaxis  Serial lumbar punctures – not recommended as CSF reforms within 6 hours, therefore short term treatment, uncomfortable, complications  Surgery – CSF shunting, optic nerve sheath fenestration

17.  Permanent vision loss is the major morbidity associated with IIH.  A recurrence of symptoms may occur in 8 to 38 percent of patients after recovery from an episode of IIH or after a prolonged period of stability. Weight gain is a common but not universal antecedent to recurrent IIH