Idiopathic Intracranial Hypertension(IIH) AKA High Pressure in the Brain

Immediate action required: Call 911 or go to ER if you have any of these symptoms and: they come on quickly, such as a sudden severe headache, change in the vision, confusion or weakness &  you have recently had a head injury, you have a high temperature, or you feel generally unwell.

Untreated IIH can result in permanent problems such as vision loss. Have regular eye exams and checkups treat any eye problems before they get worse. It's also possible for symptoms to occur again even after treatment. It's important to get regular checkups to help monitor symptoms and screen for an underlying problem.

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INITIAL TREATMENT FOR MOST: 

Some patients with normal vision and minimal symptoms require no treatment other than monitoring; most others may require risk factor modification and medications .

Address risk factors and comorbid conditions — Any potential agents that might cause or worsen IIH (eg, tetracycline derivatives) should be discontinued. However, this intervention alone may not be sufficient to manage IIH.

Similarly, patients should be questioned regarding symptoms of sleep apnea; diagnostic polysomnography and treatment of sleep apnea should follow where appropriate. Since during apneic periods cerebrospinal fluid (CSF) pressure increases , obstructive sleep apnea appears to be an aggravating factor in patients with IIH.

Weight loss — A low-sodium weight reduction program, ideally in conjunction with a nutritionist or dietician, is recommended for all patients with obesity and IIH. An approach using motivational interviewing may be especially helpful. Weight loss appears to alleviate symptoms and signs in many but not all patients . Because weight loss is difficult for many to achieve and also takes time to achieve, other treatments for IIH are required at the same time when there is visual loss present.

 Studies typically report that weight loss is associated with reductions in intracranial pressure (ICP) and/or papilledema .

Medically supervised weight loss programs or surgically induced weight reduction (eg, gastric banding or gastric bypass procedures) may be necessary in patients with severe obesity. Case series of patients with IIH undergoing gastric surgery report improvement of IIH symptoms and signs including papilledema, headache, tinnitus, and CSF pressure 

Weight gain may be a risk factor for recurrence of IIH.

Carbonic anhydrase inhibitors

Acetazolamide — For initial treatment of patients with IIH who have vision loss and/or vision symptoms.

Carbonic anhydrase inhibitors are believed to reduce the rate of CSF production and have been associated with modestly improved outcomes in patients with IIH.

 

Potential contraindications – Although a sulfa allergy is reported to be a relative contraindication to acetazolamide use, there is little clinical or pharmacologic basis for this recommendation. Nonetheless, it remains a concern for many clinicians. A true cross-reaction between sulfonamide antimicrobials and the sulfa moiety in acetazolamide and furosemide is unlikely.

 

(For patients who have had major adverse reactions (eg, Stevens-Johnson syndrome, anaphylaxis), the risk precludes the use of acetazolamide.

 

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Pregnancy, particularly the first 20 weeks, is often considered a relative contraindication to the use of acetazolamide, although limited information on safety is available

 

●Adverse effects – Medication side effects of acetazolamide include digital and oral paresthesias, anorexia, malaise, metallic taste, fatigue, nausea, vomiting, electrolyte changes, mild metabolic acidosis, and kidney stones. These are usually dose related. While many patients in the IIH experienced side effects of acetazolamide, quality-of-life measures were still higher in patients who received acetazolamide. Monitoring of electrolytes during acetazolamide treatment is not necessary if acetazolamide is the only diuretic used.

 

For patients who are unable to tolerate Acetazolamide, Furosemide and Topiramate are alternatives.

Other carbonic anhydrase inhibitors, such as methazolamide (Neptazane), can also be used in acetazolamide-intolerant patients.

Loop diuretics — For patients with persistent or worsening visual symptoms despite maximizing treatment with acetazolamide, the addition of furosemide may be necessary.

Headache prophylaxis — Patients with IIH can continue to have headaches despite improvement in papilledema and visual function. Medications used in the prophylactic treatment of migraine headaches are often used for headache management in IIH if other treatments described above are not effective in this regard . Many patients with headaches and IIH have migraine or another headache syndrome that is not directly related to increased ICP. These syndromes should be identified early and treated, as they may persist following otherwise successful IIH treatment. The choice of agent is influenced by the propensity of some of these medications (eg, valproate, tricyclic antidepressants) to produce weight gain; however, weight gain can be mitigated by use of low doses and careful monitoring of weight. (

URGENT TEMPORIZING MEASURESRare patients present with or develop rapidly progressive vision loss (ie, fulminant IIH). 

Treatment is urgent to preserve vision:

●Medical therapy – Acetazolamide should be initiated promptly and can be rapidly titrated up to 4 grams per day divided into two doses. 

In addition, short-term temporizing measures can be employed in such patients until surgery can be performed [56]:

●Glucocorticoids – In the setting of acute visual loss, a short course of intravenous glucocorticoids may be useful as a temporizing measure prior to surgical intervention in fulminant IIH.

●Serial lumbar punctures – Serial lumbar punctures or lumbar drainage can be a useful temporizing measure as a prelude to surgery . However, these are not useful for long-term management of IIH in most patients

INTERVENTIONS FOR SEVERE OR REFRACTORY DISEASE

Indications for intervention — Patients with IIH who appear to benefit from surgical intervention include those who fail, are intolerant to, or are noncompliant with maximum medical therapy . They have intractable headache and/or progressive visual loss. :

●Worsening visual field defect despite medical therapy

●Presence of visual acuity loss attributed to papilledema (ie, not due to serous detachment, macular edema, hemorrhage, or choroidal folds)

Choice of procedure — The two main surgical procedures in IIH are optic nerve sheath fenestration (ONSF) and cerebrospinal fluid (CSF) shunting procedures. Cerebral venous sinus stenting is an alternative intervention for IIH. 

The overall rate of visual improvement seems to be equivalent across all of the surgical treatment modalities, and there is insufficient evidence to recommend or reject any one surgical modality over another at this time .

Some patients require both shunting and ONSF.

Optic nerve sheath fenestration — ONSF appears to be an effective procedure in patients who have progressive vision loss despite medical therapy. It is usually performed using a medial orbital approach. The optic nerve sheath is identified and a window is cut in this sheath, allowing CSF access to the orbit. ONSF can stabilize or improve visual loss due to papilledema in IIH. In general, ONSF is an outpatient procedure, although it typically involves general anesthesia. The recovery time is typically same day.

Preservation of vision is the primary goal of ONSF. While some patients experience headache relief after ONSF, many do not . ONSF has been associated with improvement in patients with deteriorating vision loss despite a working shunt. ONSF also appears to be safe and effective in children .

 

●Adverse effects – Complications of ONSF occur in as much as 40 to 45 percent of patients . Most but not all of these are transient and nondisabling. The more common complications include:

 

•Temporary diplopia (due to injury to extraocular muscle, nerve, or blood supply) in 29 to 35 percent .

•Efferent pupillary dysfunction from ciliary ganglion damage can be seen after ONSF in up to 11 percent .

•Vision loss in up to 11 percent ]. This is usually transient but can be catastrophic and permanent in 1.5 to 2.6 percent . Vision loss can result from vascular complications (central retinal or branch artery occlusion, choroidal infarction), trauma (eg, operative traction), infectious optic neuritis, orbital hematoma, hemorrhage into the optic nerve sheath causing compressive hematoma, and other operative events 

 

●Relapse – ONSF may fail after initial benefit, requiring repeat surgery in 7 to 32 percent of eyes, depending in part on the duration of follow-up; failure may occur within months or after several years  Repeat surgery may be necessary.

Shunting — CSF shunting procedures include ventriculoperitoneal shunt (VPS) or lumboperitoneal shunt (LPS). At most centers, VPS is performed preferentially due to a higher complication rate with LPS.

 

 

Other complications of shunting include shunt infection, abdominal pain, and overdrainage causing low pressure . Rare complications include cerebellar tonsillar herniation and syringomyelia, subdural and subarachnoid hemorrhage, and bowel perforation.

Venous sinus stenting — Venous sinus stenting is a relatively new and somewhat controversial treatment option for IIH. Its use results from the observation that many patients with IIH have apparent stenoses of the transverse venous sinus or other cerebral veins, although whether this is a primary or secondary phenomenon is uncertain

• IIH is a chronic condition: IIH is a chronic condition that can be diagnosed and treated by a HCP such as a Neurologist.

https://www.youtube.com/watch?v=Tul9sm30QNo

https://www.youtube.com/watch?v=TmTGsTo1btg and https://www.youtube.com/watch?v=TmTGsTo1btg&t=72s