Your IIH Case Workup - Assessment & Analysis

Understanding the Two Senior Cases

Your History - Suggested Wording (Modelled After Your Senior's Format)

CASE WORKUP SHEET

1. Progressive decrease in vision [both eyes / right > left / left > right] since [X days/weeks/months] [2. Headache since X days - if present]

HOPI:

• [History of headache]: [Patient has / does not have] history of headache. [If present: It was located in the [bifrontal/suboccipital/holocranial] region, [dull/throbbing] in nature, [continuous/intermittent], without/with nausea and vomiting, aggravated by [lying down/Valsalva/bending forward], and radiated to [X region].]
• [History of diplopia]: Patient [has / does not have] history of double vision, which was [transient/constant, horizontal/vertical].
• [Tinnitus]: There is [no / a] history of ringing/pulsatile sensation in the [right / both] ear(s).

• No history of pain around the eyes while moving (no pain with eye movements)
• No history of redness or watering from eyes
• No difficulty in perceiving colour (no colour vision disturbance)
• No history of floaters coming in between vision
• No perception of image as vibrating (no oscillopsia)
• No history of macropsia or micropsia
• No worsening on standing up or bending forward
• No history of any similar episodes in the past or transient loss of vision
• No history of trauma
• No history of weakness or sensory symptoms in any limbs or body part
• No history of seizure or any other focal neurological deficit
• No history of neck pain or back pain
• No history of diplopia [or: History of transient diplopia - as applicable]
• No history of ringing sensation in ears [if tinnitus absent]
• Drug history: No history of intake of hormonal pills (OCP/steroids/tetracyclines/Vitamin A), or any other drug intake

Other Neurological Symptoms:

Other Systemic Symptoms:

Menstrual History (if female patient):

Changes / Additions to Your History Wording

Symptom Analysis and Localisation Table

Key Things Your Senior Included That You Must NOT Miss

1. Autonomic negative history (Dr. Sanjay Shree): "No history of orthostatic dizziness, or heat/cold intolerance, or increased/decreased sweating" - this rules out autonomic neuropathy mimics.
2. "No worsening on standing or bending forward" (Dr. Parth Valera) - specifically asked in IIH to document raised ICP symptoms.
3. Specific dates for progression - use dates or "Day 1, Day 3" to show exact timeline.
4. Drug history must name specific drugs - OCPs, Vitamin A, tetracyclines are secondary IIH triggers.
5. Menstrual history - mandatory if female patient.
6. Family history + similar illness - explicitly state "no similar illness in any family member."
7. "Vision is static and not further worsened" at presentation - document current status as Dr. Parth did.
8. Describe the blackout episodes as "transient sudden blackening of vision lasting few seconds, intermittent" - TVOs are a cardinal IIH symptom.
9. Night/day difference in vision - always ask; helpful for localisation table.

Symptom Analysis and Localisation

Summary Localisation Statement

Notes on Your Table vs Dhanvi Kumari's Case

• No TVOs in your patient - so you do not include the "transient blackening of vision" row that the senior had. If TVOs are absent, you can add a negative line in HOPI: "No history of sudden transient blackening of vision."
• No tinnitus - similarly omit that row from the table.
• No day/night difference - if your patient did not report better vision in dim light, omit that row or note it explicitly as absent in HOPI.
• The suboccipital headache with radiation is a strong feature in your case just like Dhanvi's - this is a key row that Dr. Parth included in the summary but did not separately tabulate. You can add it as a row (as I have above) since it directly supports raised ICP localisation.
• Diplopia in your patient similarly points to CN VI false localising sign - tabulate this clearly as your senior summarised it in the narrative but did not break it into the table separately.

Differential Diagnosis - Dhanvi Kumari (14F, IIH Presentation)

Clinical Problem to Solve:

Primary / Most Likely Diagnosis

1. Idiopathic Intracranial Hypertension (IIH) / Pseudotumor Cerebri Syndrome

• Young female (IIH is most common in women of childbearing age, but occurs in adolescents)
• Bilateral progressive visual loss with peripheral field loss (arcuate/nasal step defect - earliest field change in papilledema)
• Transient visual obscurations (TVOs) if present
• Transient diplopia - CN VI false localising sign of raised ICP
• Headache
• Started on Acetazolamide by ophthalmology (treatment response supports diagnosis)
• No mass on imaging (MRI brain normal expected)

• Age 14 (IIH more common post-puberty; this patient is at menarche - 3rd cycle, which is actually a valid IIH risk window)
• Not overweight/obese (classical IIH risk factor - not documented)
• No hormonal pill use
• Sudden onset over 3 days (IIH is typically more insidious; acute presentation raises suspicion of secondary cause)

• Papilledema + raised CSF opening pressure (≥250 mmH₂O in adults; >280 in children) + normal CSF composition + normal MRI (no mass, no hydrocephalus) + no other cause identified

Secondary Pseudotumor Cerebri Syndrome (must rule out BEFORE diagnosing IIH)

2. Cerebral Venous Sinus Thrombosis (CVST) ⭐ HIGH PRIORITY

• Acute/subacute onset visual loss with raised ICP (exactly like Vilash Singh's case which turned out to be CVST on MRV)
• Right facial puffiness and eye deviation noticed by mother - could suggest venous congestion / CN VI palsy from raised ICP
• Suboccipital headache with radiation - CVST headache can be occipital, holocranial, or localised
• Age 14, female - CVST occurs in young women; in children, ~50% of cases are in neonates/infants but adolescent cases are well-documented
• No obvious IIH risk factors (not obese, no drugs) - raises suspicion for secondary cause
• TVOs + papilledema are classic CVST presentations
• CVST causes raised ICP by impaired venous drainage → impaired CSF absorption
• Thrombophilia screening is mandatory (hypercoagulable state in a 14-year-old)

• No focal neurological deficit documented (CVST can present without focal signs)
• No seizures (common in CVST but not universal)
• No fever (septic CVST excluded)

3. Intracranial Space-Occupying Lesion (SOL) with Mass Effect / Obstructive Hydrocephalus

• Raised ICP features: headache, bilateral visual loss, CN VI palsy (diplopia)
• Progressive course over days
• Age 14 - posterior fossa tumours (medulloblastoma, ependymoma, cerebellar astrocytoma) common in adolescents
• Suboccipital headache specifically raises suspicion of posterior fossa pathology
• Eye deviation noted by mother (could be acquired squint from CN VI palsy or CN IV)

• No imaging evidence described (AIIMS MRI presumably normal - Acetazolamide started suggesting IIH considered likely)
• No vomiting described (classic raised ICP triad: headache + vomiting + papilledema)
• No ataxia or gait disturbance mentioned
• Vision is static and not worsening further at presentation

4. Inflammatory / Demyelinating Optic Neuropathy - Bilateral (Neuromyelitis Optica Spectrum Disorder / MOG-IgG Associated Disease)

• Bilateral optic nerve involvement (RT > LT)
• Sudden onset over days (NMOSD/MOGAD can be acute)
• Age and sex (NMOSD/MOGAD: young women)
• Peripheral and diffuse field loss patterns

• No pain with eye movements (a hallmark of optic neuritis - specifically PAIN on eye movement)
• No colour vision disturbance documented
• No redness of eyes
• Bilateral simultaneous acute optic neuritis without pain is atypical for typical MS-associated ON
• Headache and diplopia pattern more consistent with raised ICP than optic neuritis
• Acetazolamide would not be the treatment choice (steroids would be first-line)
• No prior episodes of neurological illness

5. Infiltrative / Compressive Optic Neuropathy - Bilateral (Optic Nerve Sheath Meningioma / Glioma / Leptomeningeal Disease)

• Bilateral progressive visual loss
• Peripheral field loss
• Age appropriate for optic pathway glioma (though NF1 would be expected)

• No NF1 stigmata mentioned
• Bilateral simultaneous optic glioma rare without NF1
• No disc pallor described (early papilledema more likely than atrophy)
• Acute onset over 3 days less typical for slow-growing tumour
• Diplopia and headache better explained by raised ICP mechanism

6. Drug-Induced / Secondary Pseudotumor Cerebri

• Several drugs classically cause raised ICP mimicking IIH: tetracyclines (minocycline, doxycycline), Vitamin A/retinoids, growth hormone, thyroxine (in children), OCPs

• Drug history explicitly states: no hormonal pills, no drug intake
• No antibiotic use documented
• Effectively excluded by history if drug history is reliable

7. Metabolic / Endocrine Causes (Thyroid Disease, Addison's, Hypoparathyroidism)

• Can cause raised ICP (thyroxine replacement in children, hypothyroidism/hyperthyroidism can rarely cause pseudotumor)
• Systemic symptoms should be sought

• No systemic symptoms (no weight gain/loss, no fatigue, no cold intolerance mentioned)
• No history of thyroid disease
• Less likely given acute presentation

Summary Differential Diagnosis (Prioritised)

Critical Point for Your Case Workup

• Both present identically (raised ICP, papilledema, visual loss, diplopia, headache)
• CVST is a secondary pseudotumor - must be excluded BEFORE diagnosing IIH
• Per Bradley & Daroff: "Cerebral venography (usually with MRV) should also be pursued to rule out CVST - an IIH mimic"
• The right facial puffiness and eye deviation in Dhanvi's case makes CVST a particularly important differential to exclude
• Vilash Singh (your senior's other IIH case) initially appeared to be IIH but turned out to have CVST on MRV - this is a direct clinical lesson from your department

Differential Diagnosis - Dhanvi Kumari (14F)

Working Diagnosis (Most Likely)

1. Idiopathic Intracranial Hypertension (IIH) / Pseudotumor Cerebri Syndrome

• Young female at menarche (3rd cycle) - recognised risk window
• Bilateral progressive visual loss RT > LT with peripheral field loss (arcuate/nasal step - earliest papilledema field defect)
• CN VI palsy (transient diplopia) - classic false localising sign of raised ICP
• Suboccipital headache
• Eye deviation noticed by mother (CN VI)
• Acetazolamide started by ophthalmology - clinical diagnosis made

• Sudden onset over 3 days (IIH typically insidious - acute onset should raise suspicion of secondary cause)
• No obesity documented (classical IIH risk factor absent)
• No drug/hormonal pill use
• Age 14 (more typical post-puberty, but menarche onset makes it valid)

Secondary Pseudotumor Cerebri - Must Exclude Before Diagnosing IIH

2. Cerebral Venous Sinus Thrombosis (CVST) ⭐ HIGHEST PRIORITY TO EXCLUDE

• Acute raised ICP presentation without classical IIH risk factors (not obese, no drugs)
• Right facial puffiness - suggests venous congestion/obstruction
• Young female - CVST occurs in adolescent females
• Presents identically to IIH (papilledema, visual loss, CN VI palsy, headache)
• Thrombophilia at age 14 must be excluded
• Clinical lesson from same department: Vilash Singh presented as IIH but MRV showed bilateral CVST

• No seizures (common but not universal in CVST)
• No focal neurological deficit beyond CN VI
• No fever (septic CVST excluded)
• Vision static at presentation (not acutely worsening)

3. Posterior Fossa Space-Occupying Lesion / Obstructive Hydrocephalus

• Suboccipital headache specifically - classic posterior fossa symptom
• Raised ICP features: headache + bilateral visual loss + CN VI palsy
• Age 14 - posterior fossa tumours (medulloblastoma, cerebellar astrocytoma, ependymoma) are common in this age group
• Eye deviation noted by mother

• No vomiting (Cushing's triad incomplete)
• No ataxia or cerebellar signs mentioned
• No morning headache/waking at night
• MRI brain (done at AIIMS before LP) would exclude this

4. Bilateral Inflammatory Optic Neuropathy - NMOSD / MOG-IgG Associated Disease (MOGAD)

• Bilateral optic nerve involvement, acute onset over days
• Young female (NMOSD/MOGAD predilection)
• Progressive visual loss with peripheral and diffuse field loss

• No pain with eye movements (hallmark of optic neuritis - its absence weighs strongly against)
• No colour vision disturbance
• Headache and CN VI palsy better explained by raised ICP than bilateral optic neuritis
• No prior neurological episodes
• Acetazolamide (not steroids) started - treating physician considered raised ICP not optic neuritis

5. Drug-Induced / Iatrogenic Raised ICP (Secondary Pseudotumor)

• Classic culprit drugs: tetracyclines, Vitamin A/retinoids, growth hormone, thyroxine (in children), OCPs, steroids (withdrawal)

• Explicitly excluded by history: no hormonal pills, no drug intake
• Effectively ruled out if history is reliable

6. Endocrine / Metabolic Cause (Hypothyroidism, Hyperthyroidism, Addison's, Hypoparathyroidism)

• Thyroid replacement in children is a recognised secondary pseudotumor cause
• Metabolic causes can mimic IIH

• No systemic symptoms (no weight change, cold intolerance, fatigue)
• No history of endocrine disease

Differential Diagnosis - Summary Table (for Case Sheet)

One Sentence to Write in Your Case Sheet Under DDx