UNDERSTANDING “IIH” – FAQ’S

“(the cranium is) Just like carry-on luggage, only so much can fit…one pair of socks to many, and the seams start to strain.”

I’ve only lived with IIH for a few years – much less time than many, many others I encounter in support forums.  Lately I’ve taken notice of newly diagnosed patients who seem to be as perplexed at the lack of information and explanation of their condition as I remember being in 2017 when I was told “Nobody knows nothing about IIH.” (paraphrase). 

Judging by the bewildered posts of new members of our auspicious group, there hasn’t been much change.

What follows is the beginning of a “Frequently Asked Questions” section of Shuntwhisperer.  The information here is a combination of 1) my personal experience, observation of others with IIH/PTC/ETC, 2) published research that is fairly abundant for a disorder that seems to amount to a Black Hole of Understanding, 3) readily accepted tenets of human physiology, and 4) the babblings and savante-garde notions of a guy with a hole in his head and a tube in his brain.

Fair warning, take it for what its worth ; )

In all seriousness, I pray this helps those seeking answers, and as always, it’s not about me being right, it’s about getting others to think and talk about IIH in the hopes that this dialog will spark understanding and improved quality of life for everyone. 

Thus, with the timelessness of the inspired dialog of Shakespearean-trained actor Patrick Stewart,

“ENGAGE!”

 

FREQUENTLY ASKED QUESTIONS ABOUT IIH

Short Answers First, Technomedical Stuff Second

WHAT IS “INTRACRANIAL HYPERTENSION”?

Short Answer:

“Intracranial Hypertension”, or “IIH”,  is one name for a group of complex disorders in which an individual develops physical signs and symptoms caused by abnormally high pressures of the fluids in and around the brain.* 

 

Geek Stuff:

The adult human brain is enclosed in a protective bony compartment of the skull known as the cranium.  The main contents of the cranium are the brain, connective tissue (meninges), and two fluids: blood and cerebrospinal fluid (CSF).

Because the cranium is rigid and has a fixed volume, net accumulations of either fluid will increase the pressure inside the cranium (Intracranial Pressure, or ICP).

“Intracranial Hypertension” results when an individual’s tolerance for normal pressure variations becomes compromised, especially high pressures.  These pressures can affect the brain itself, becoming stressed with predictable results   It is referred to by several abbreviations which likely represent individual variations of the same “disorder”:

  • IIH – “Idiopathic (‘of unknown origin’) Intracranial Hypertension
  • NPH- “Normal Pressure Hydrocephalus” –  A very misleading term that is contradictory and would only apply to true conditions of hydrocephalus, a condition where Cerebrospinal Fluid becomes trapped due to developmental or traumatic factors, allowing the very slow forming CSF to accumulate in isolated areas under significant pressure, causing deformation and/or damage to the brain tissue
  • BNPH- “Benign Normal Pressure Hydrocephalus” – Another extremely misleading term, as with “NPH”, along with the fact it is anything but “benign” (harmless)
  • PTC – “Pseudotumor Cerebri” – literally, “false brain tumor”, one of the earliest names given to this class of disorders due to the fact that a patient’s symptoms usually mimic those of a brain tumor, but upon CT/MRI, no tumor is evident.

I consider these “different” diagnoses to be representations of a similar disorder, expressing itself differently in individual patients due to their particular physiology.   Consequently, I refer to these disorders as Intracranial Pressure Dysregulation Disorders, or ICPDDs.

427420290-cerebellar-vermis-metencefalon-cerebral-hemisfere-brain-lobe
The Brain and its supporting anatomical structures are encased in a rigid bony protective compartment of the skull known as the cranium.  Just like carry-luggage, only so much can fit inside.  One pair of socks too many, and the seams start to strain.

*Growths of soft tissue such as tumors and cysts may also increase ICP with similar presentation; however these conditions fall into different diagnostic and treatment categories.  For the purposes of discussing the ICPDDs, the focus will be on blood and cerebrospinal fluid, assuming there are no abnormalities of the soft tissues in the cranium, including the brain itself. 

 

WHAT IS THE SOURCE OF “INTRACRANIAL PRESSURE”?

Short Answer:

Intracranial Pressure, or ICP, is the created by high volumes of blood being pumped into an extensive network of blood vessels that support the brain. (This is the foundational principal of Intracranial Pressure Dynamics, hence my appellation “Cerebrovascular ICP Dominance Principal”).**

Geek Stuff:

The brain requires more energy than any other organ in the human body.  That energy is delivered by blood containing oxygen and glucose.  Blood also carries away metabolic waste from brain cells (neurons).

  • Big Numbers Alert: The adult brain has an estimated 100 billion cells called neurons.  Getting blood to each neuron requires a vast and intricate network of blood vessels estimated to be up to 100,000 miles in total length.  The majority of the vessels are so small that blood cells must pass through one at a time.

Blood enters the brain through arteries under high pressure (Average Mean Arterial Pressure of 90 mm Hg) and volume (750-1000cc per minute).  Resistance to the flow of viscous blood (~1.8 times “thicker” than water) through the network of vessels creates pressure in the vessels.  This pressure is transferred from the blood vessels to the brain tissue and ultimately into cerebrospinal fluid in and around the brain and spinal cord, creating what is termed “Intracranial Pressure.”

**Shortly after arriving at and naming this principal “Monro-Kellie 2.0” in Millennial TechnoEvolutionary Credit to the Monro-Kellie Principal, I discovered a cheeky neurosurgeon of “Her Majesty’s Royal College of Medicine, London” had published a paper on this very subject in 2016.  His name is Wilson.  Dr. Mark Wilson.  His publication:

Monro-Kellie 2.0: The Dynamic Vascular and Venous Pathophysiological Components of Intracranial Pressure

This publication, accurate and well written, was obviously composed by MI6 as cover for “Dr. Agent” Wilson.  Subterfuge aside, it does make both Agent…excuse me, Dr. Wilson and myself seem like a pair of bright bulbs.  Nonetheless,  a pair of very stiff upper lipped chaps suggested I change the name by which I referred to this principal, in the name of the Queen…and my kneecaps.

And I do favor mine very, very dry, and of course…

Shaken…not stirred.

XE3_00992_XL
“Dr.” Mark Wilson, Neurosurgeon

 

WHAT IS “NORMAL” INTRACRANIAL PRESSURE (ICP)?

Short Answer:

Intracranial Pressure is not a fixed, unchanging value.   ICP is dynamic by virtue of its origin in the volume and pressure of blood flowing into the brain, which is in turn inside of the rigid cranium with a limited amount of available space.  Factors affecting systemic blood pressure and an individual’s response/reaction to those factors, will cause ICP to vary as well.  “Normal” ICP is a patient-specific range of pressure determined by individual physiology.  Thus, for each of us, “Normal ICP” is any pressure that allows healthy & asymptomatic brain function.

Geek Stuff: 

While scientific studies establish an average of 110 mm of water (defined as the pressure at the base of a water column 1mm in diameter and 110mm tall), the truth is that “normal” ICP varies from person to person, again for reasons of individual physiology.  Furthermore, ICP varies in an individual over periods from as few as a few minutes to as long as years as dynamics of blood flow and CSF production fluctuate.

All aspects of ICP are dependent on the fact that blood is the only fluid that enters the cranium/brain.  Therefore the pressure and flow of that blood directly affect ICP, and hence the fact that an individual patient’s ICP varies within a personal range and is not a static value.

Finally, the brain itself ensures it receives adequate nutrient-rich blood, controlling blood flow through heart rate/contraction, as well as other critical factors including systemic blood pressure, available oxygen in the air (partial pressure of oxygen), a patient’s lung health (presence/absence of fibrosis, COPD, smoker, and other factors that affect gas exchange with blood in the lungs), health of the blood (anemia, hemoglobin, age/size of blood cells), as well as environmental factors including barometric pressure (and hence altitude), heat, humidity…the list goes on.

In a word, any condition that potentially hinders a person’s brain from getting adequate oxygen in the smallest quantity of blood possible, or which makes their tolerance for ICP fluctuations more narrow, or changes the dynamics of those fluctuations to higher ranges for longer periods potentially predisposes them to developing an ICPDD.

Mayfield-Clinic-Pic
Chiari Malformations are essentially brains too big for the available cranium…or vice versa.  The result is less available volume to allow a patient to tolerate ICP fluctations, not to mention the potential interruption of CSF circulation between the cranium and spinal cord, aka “corking” (credit to Dr. Diana Driscoll and her ongoing body of work, “The Driscoll Theory”)

See FAQ Topic “HOW DOES ICP BECOME ELEVATED?” (coming soon to a url near you! 7/30/2019)

 

WHAT CAUSES ICP TO BECOME ELEVATED?

(That was fast!)

Short answer: too many socks in the carry-on luggage.

The adult cranium is a rigid bony case and does not expand or contract. After the bony plates of the skull fuse in adulthood, it has a defined available volume.  If one or more of the contents of the cranium accumulates without a matching decrease in the other contents, the pressure within the cranium predictably increases.*  For the purposes of discussion of ICPDDs, blood and cerebrospinal fluid (CSF) will be the only cranial contents considered to affect ICP.  Growths of soft tissue such as tumors and cysts can also increase ICP, however these conditions generally fall into different diagnoses and treatments.

Looking at blood and CSF, it becomes apparent that blood is the dominant, driving force behind ICP:

  • Blood is the only fluid to enter the cranium, at a rate of nearly one liter per minute at rest, a figure that represents approximately 20% of cardiac output.  This is because the brain demands enormous quantities of oxygen and glucose to function, and actively regulates the amount of blood it receives in real time.
  • By contrast, Cerebrospinal Fluid (CSF) is a by-product of brain function.  It is “distilled” by osmosis in specialized cells lining small hollow (normally) interconnected areas within the brain known as ventricles, as well as by similar tissue along the outside of the brain.  It is produced at a mere 0.35cc/minute from arterial blood, and as such accounts for only 0.0004% of the fluid dynamics within the cranium, with blood accounting for 99.9996%.
  • Blood and CSF are both present in the cranium in approximately equal volumes of 150 cc.  The blood volume enters and exits at approximately 6-7 times per minute; CSF is produced and replaced approximately every 7 hours.
  • CSF flow passively in and around the brain, following pressure gradients from areas of production to areas where it is absorbed by veins and lymphatic tissue.  This passive circulation is aided by pulsations of blood vessels in the brain as well as physical movement of the body.

ICP becomes elevated if blood and or ICP accumulate at a greater rate than they are removed from the cranium.  Due to the high flow rate of blood into the brain, even the smallest deficit in drainage of blood from the brain becomes a potential source for rapid elevations of ICP; this is known as (Chronic) Cerebrospinal Venous Insufficiency, or CCSVI, but could more accurately be termed Cerebrovascular Outflow Insufficiency, Acute and/or Chronic.  This is likely the source of elevated ICP in patients who do not have isolated pockets of non-draining CSF (“Non-Communicating Hydrocephalus”); however, Cerebrovascular (Blood) Dynamics and Cerebrospinal Fluid (CSF) Dynamics are inextricably linked due to the enclosed nature of the cranium**.

NIagara Falls
Cerebrovascular ICP Dynamics
frozen waterfall
CSF Dyamics

 

*Monro-Kellie Doctrine

**”Monro-Kellie 2.0, The Pathophysiology of Cerebrovascular Dynamics in Intracranial Pressure”, Dr. Agent Mark Wilson, Royal College of Medicine Branch, MI6

 

 

 

 

 

4 thoughts on “UNDERSTANDING “IIH” – FAQ’S

  1. I was going to reply on my post but it’s gone. Wonder Woman 72 here. I think I figured out what set me apart in my journey was that I have a large bulging disk in C- spine which I believed caused my fluid not to move properly. I still struggle but I have improved greatly since moving out here to California. Acupuncture has been amazing which has also helped my vision as he works in that separately. Anyway thanks again for steering me in the right direction it definitely helped.

    1. Trisha: WordPress ate several comments in a technical glitch (go figure), but I found your original post in my archives.

      I have noticed that neck injuries and misalignments seem to figure prominently in the health histories of those who have acquired “IIH”. Trina had suffered a severe whiplash injury to the point where the curvature of her neck was reversed (“Reverse Lordosis”). Despite a large body of research detailing the potential problems such conditions cause, she was repeatedly told “it’s not a problem.”, even when it was obvious that it was. She also suffered atlanto-occipital instability with visible movement of her cranium on C1 (not supposed to happen), but again was repeatedly told “it’s not important.”.

      I’m glad to hear you are getting help with acupuncture, and thank you for posting about your experience for the benefit of us all. Prayers to everyone for Comfort, Healing, and better days.

      Here is the body of your original post:

      wonderwoman72 commented on #CROWDHEALING VALIDATED: IIH, EDS, & POTS: THE DRISCOLL THEORY (AND NOW, ADRENAL FATIGUE: TAKING IT ON THE LAM)

      Starting this weblog over a year ago was primarily borne out of a desire to help with a disorder that even the doctors I …

      https://youtu.be/YficBlvPwWQ
      I had to share this with you. As Diane Driscoll talks about the Vagas Nerve and then reading and finding about natural stimulation I stumbled on this guy. Wim Huf!!! I told my husband yesterday that my head was about to burst and currently not even able to be home with my family due to elevation. No I don’t if a shunt in my head but I do have a large hole in my head my a resection last year. But regardless extreme sensitivity to elevation, barometric pressure food and pots and just a messed up body. Day 1 of this . Noticeable changes. Learn his breathing techniques then I’ve cold shower. I feel like a different person. Like me!!!! Anyway had to share with you because I am also on the road to beat this thing!!! Here s to the memory of your sweetie!!! Just maybe one more thing that may help. I would have never connected the dots if not for your site and information about Diane Driscoll. But Wim Huf is the man . Please watch his videos.

  2. My daughter has a pretty unusual case of IH. She has blockage in her sigmoid sinus infection both sides. Luckily, she does not have swelling of her ocular nerve. She has dealt with this pain for 8years (started when she was about 15 for unknown reason but maybe because she was a springboard diver??? No trauma though) she is now 23. At first they thought she had migraines even though her head pain started in morning and intensified throughout the day. She then was diagnosed with occipital neuralgia. However treatments for that didn’t seem to help either other than one nerve block. Repeated nerve blocks did not help. Then she was thought to have migraines but the various drugs including the inhibitor’s such as Amovig made things worse. She also tried Botox injections in her head. Again this was only minimally helpfulAnd that wasn’t effective either. She was then told to take an MRV which showed the blockage in her sigmoid sinus and gave her the diagnosis of IH. Because of her combination of the fact that she does not have swelling of her ocular nerve and she is not overweight and she is young she is in the 5% category of outliers of H. She was told not to get a spinal tap done for complications that could arise and for the fact that it may not even indicate any information since she didn’t have swelling of her ocular nerve. Instead they advise that she should start on Diamox and see if that helped to confirm the diagnosis. After trial and error as to how to take the Diamme ox it did help significantly and she takes six tablets of 250 mg spread out through the day about every 2 to 3 hours. What is fascinating about your information is that there seems to be a missing element in her medication or she may need to increase her medication because she has a definite response to weather changes and barometric changes. We cannot seem to find a Doctor Who has an understanding Of the interaction of weather. We simply want to know what she should take as the missing component of her medications to come back this. It may even be as you suggest oxygen? My daughter asked actually if oxygen can be obtained in sort of a inhaler type smaller version than the one that you show on your website so that it could be more discrete if she needs to use it at her work. Nonetheless I will I would greatly appreciate being able to email you and determine if you have any suggestions regarding doctors or to at least get some information as to where you are now since I could not tell what your current situation is and what you have learned currently since some of it seemed dated back in 2017 although frankly I didn’t see or look extremely closely at all the posting dates so I may be incorrect. It would just be very informative to speak to you or somebody who actually has knowledge about these issues or can direct me to doctors who have familiarity with these issues. Given the Tele health situation, many doctors are assisting patients even if they are not in their location so it might give Marisa an opportunity to speak to those that you think would be helpful.Thank you so much in advance and I hope you are well.

    1. Shari: First of all, my heartfelt prayers for you and your daughter. This can be a frustrating disorder to manage without information, which is the reason I started Shuntwhisperer – simply to offer my experience and what passes for insight with my particular Intracranial Pressure Dysregulation Disorder.

      To understand this class of disorders, know that the primary source of intracranial pressure (ICP) is caused by the hydraulic resistance of up to one liter/minute of viscous blood being pumped at an average of 95mm HG (1.8psi/1291mm H20) Mean Arterial Pressure through approximately 100,000 miles of blood vessels in the brain. These vessels, embedded in the brain, swell under the pressure. Cerebrospinal fluid (CSF) acts, among other functions, as an incompressible fluid between the brain and the intact cranium. CSF is the secondary source of ICP, being “distilled” in the brain ventricles at .3-.5cc/minute. The sum of these two components, vascular and CSF, results in ICP. ICP itself varies according to the balance of two factors: blood pressure and flow into and out of the brain (stick a pin in that), and the rate of CSF formation. Both factors can be influenced by environment, exertion, pharmacodynamics, physical and emotional stress, as well as hormonal imbalances. This is all verifiable by the published, peer reviewed research so readily available, but curiously sitting on dusty shelves.

      Coming back to your daughter: bilateral venous stenosis would suggest Chronic Cerebro Spinal Venous Insufficiency (CCSVI). In simple terms, blood cannot flow out of the brain as quickly as it is being pumped in, resulting in pressure buildup as the heart forces arterial blood into cerebrovascular vessels. The brain swells against the cushion of CSF which in turn is resisted by the intact bone of the cranium. If a patient’s particular physiology cannot tolerate that pressure, neurologic and neuroendocrine dysregulation ensue. Symptoms can be predicted by looking at a map of the functional areas of the brain most susceptible to increased pressure and include headaches, fibromyalgia pain, visual changes with or without optic nerve involvement, difficulty walking, tinnitus, behavioral changes with lability….just to name a few. Our brains are miraculously complex organic computers, but being organic and soft, are subject to functional alteration as ICP “squeezes” first the exposed outer cortex and ventricular linings, then deeper areas as the disorder becomes chronic.

      Moving this discussion into the question about your daughter’s reaction to barometric pressure and weather: it is well documented that changes of as little as 10 millibars at the rate of 2 millibars/hour have a proven impact on neurologic disorders, to wit: Multiple Sclerosis patients experience symptom/pain flares; patients living with seizure disorders have markedly increased seizure activity. Migraine Spectrum Sufferers have increased frequency and severity of headaches. Intracranial Pressure Dysregulation Disorders sufferers almost to the person report negative impact from both barometric pressure changes and severe weather. I believe this is due to a combination two factors: Autonomic Dysfunciont and closely related, HPA Axis Dysfunction. The HPA Axis is comprised of the Hypothalamus gland, Pituitary Gland, and Adrenal Glands. The first two are located in the brain; the adrenals sit atop the kidnes. The HPA Axis communicates via hormonal signaling to control physiologic functions including response to temperature. Without exhausting ado, I believe from experience and study that elevated ICP dynamics that exceed patient tolerances cause the amazingly delicate, complicated interactions and functions of the HPA axis to become suboptimal. Hormonal Axis systems are very interdependent; when one component fails to respond appropriately to signaling from member components, the system becomes dysregulated, and associated physiologic functions are impacted. In the case of barometric temperature, the hypothalumus gland becomes the reverse-engineered suspect, as well as areas in the brain stem that are now being shown to respond to changes in barometric pressure. Now, Autonomic Dysfunction: this is the nervous system equivalent of endocrine dysfunction. The autonomic nervous system is like a pice of software running in the background in concert with the endocrine system to control physiologic function. There’s an old saying, “As goes the body, so goes the mind; as goes the mind, so goes the body.” This philosophical gem highlights the fact that mind (brain) and body are linked by a “hardwired” system of nerves. The autonomic system controls bodily functions through direct feedback from organs to the brain and from the brain to organs. Back to HPA Axis Dysregulation: if endocrine control of target organs is disrupted, so will the nerve feedback to the brain. If the brain becomes disrupted due to ICP, so to does the nerve feedback to the organs. To summarize, I believe the interdependency of hormonal and autonomic systems inherently implies mutual dysregulation of both systems should one or the other become affected. Until balance is restored, the body and brain are like a computer with, well, Windows. Normal response become exaggerated, inappropriate, or absent, and this, I believe is the source of increased symptoms due to barometric pressure and temperature changes.

      Take a breath, not done yet.

      Another area of weather impact is what is known as atmospheric infrasound. This is extremely low frequency, high energy “sound” created by collisions of air masses associated with storms. Infrasound can’t be heard by 99.9% of people, but it can be sensed, creating symptoms ranging from anxiety, fear, and other negative emotions to outright pain. It is documented to decrease physical performance in athletes. Infrasound travels very long distances, hundreds if not thousands of miles. In my case, during the period when I was leaking CSF around my shunt catheter and had transitioned from Intracranial Hypertension to Intracranial Hypotension, I could tell a bad storm was coming 36-48 hours before there was a change in the barometer. I discovered that using “over the ear” active noise-cancelling headphones almost immediately improved how I felt – with or without music. It’s the same idea as plane passengers using the same headphones to cancel out the low frequency drone of the jet engines.

      Back to your daughter. Her path to diagnosis actually sounds relatively quick, though I’m sure it did not feel as such. I’m also impressed that advice was give against a lumbar puncture – kudos to the whoever recommended that. The pressures obtained during LPs have no scientific basis as to how they related to Intracranial Pressure Dysregulation Disorders. Normal pressures for one patient may be pathological for another; puncture sites can (and do) leak CSF, pose risk for infection as well as nerve damage. The fact that diamox is helping is good; however, Diamox/acetozolamide primarily inhibits CSF production. If your daughter truly does have a stentotic sigmoid sinus, the cause of her elevated ICP is cerebrovasular/CCSVI, not CSF. Treating the stenotic sigmoid sinus with balloning/stenting might be a more optimal treatment as it addresses the chief cause of her elevated ICP. I recommend discussing this with her neurosurgeon; if you require a second opinion, I recommend a teleconference with Dr. Nicolas Marko at Lewis-Gale Hospital in Salem, VA. His office phone number is 1.540.444.1420. Dr. Marko is a very accomplished neurosurgeon with impressive credentials and a genuinely pleasant and sincere doctor.

      Oxygen therapy decreases blood flow to the brain by increasing oxygenation of arterial blood. The brain is the most oxygen/glucose hungry organ in the body, demanding 15-20% of cardiac output at rest. Breathing 2 liters/minute of 100% oxygen has been shown to stop cerebrovascular migraines in as little as 30 seconds. I have personally experienced this. “Small and discrete” is a challenge due to the volume of oxygen required considering its effectiveness, time for relief, and frequency of migraines. Furthermore, while oxygen therapy is extremely safe, a physician should be involved; prescription for a small O2 cylinder and facemask for documented “headaches” might be covered by insurance as well.

      Regarding her response to weather and barometric pressure: this is hard. Definitely try noise cancelling headphones, but they likely will not help with barometric pressure changes. I wish I could say “consult a neurologist”, but my experience with this path has not been productive, and we’ll leave it at that. Now: last year my neurosurgeon revised my shunt and sealed the bone around my shunt catheter. Miraculously, my sensitivity to weather has disappeared 95%. Based on this fact and observations in other patients, I am noticing that abnormally high or abnormally low ICP seems to increase susceptibility to barometric pressure changes. I “managed” my weather symptoms by trial and error, frequently resorting to bedrest because I wasn’t able to function until, literally, the storm had passed. There are considerations regarding possible CSF leaks and other issues I would be glad to share them with you by email, Shuntwhisperer@shuntwhisperer.com.

      Last, let’s go into the tall grass about the evolution of your daughter’s condition. IIH/ICPDDS are either primary (genetic/developmental) or secondarily acquired via trauma, certain drug therapies including birth control, and long term physical and/or emotional stress. I recommend a book by Dr. Michael Lam, “Adrenal Fatigue Syndrome”, and his website DrLamCoaching.com. I also recommend visiting a the website of Dr. Diana Driscoll, PrettyIll.com. These resources delve into areas that do not at first seem immediately relevant to elevated ICP, but I found them to be critical pieces of my puzzle, and I hope you do as well. These resources substantiate an undeniable link between brain function/body function in both directions, the need to consider both in management of elevated ICP, as well as how elevated ICP can cause the development of conditions previously thought to be strictly genetic in nature, with one example being a form of Ehlers-Danlos Syndrome as a result of poor GI absorption secondary to autonomic dysfunction. Don’t focus on that mouthful. Focus on your daughter and her symptoms. Be her advocate, listen to that voice in your head. Physicians have expressed dismay that I “Google”, but I can’t understand why it’s not a problem if they do it.

      If they do it.

      I’ll stop here. I hope I have helped somewhat. Please feel free to email me, and as always, prayers for comfort and healing for both your daughter and yourself.

      Wes
      The ShuntWhisperer

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