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Hydrocephalus symptoms

Search for hydrocephalus symptoms. Find Symptoms,Causes and Treatments of Hydrocephalus.For Your Health Hydrocephalus can happen at any age, but it occurs more frequently among infants and adults 60 and over. Surgical treatment for hydrocephalus can restore and maintain normal cerebrospinal fluid levels in the brain. Many different therapies are often required to manage symptoms or functional impairments resulting from hydrocephalus The symptoms of hydrocephalus can vary significantly from person to person and mostly depend on age. Conditions other than hydrocephalus can cause similar symptoms so it is important to see a doctor to receive proper diagnosis and treatment Hydrocephalus, or excess fluid in the brain, causes slightly different symptoms depending on the type of hydrocephalus and the age of the person affected. Hydrocephalus from birth. Babies born with hydrocephalus (congenital hydrocephalus) often have distinctive physical features. These can include: an unusually large hea

Symptoms of hydrocephalus can be different depending on your age. In babies, they include: An unusually large head that gets bigger quickly The soft spot on top of a baby's head is firm or bulgin Signs of a shunt malfunction include headaches, vision problems, irritability, fatigue, personality change, loss of coordination, difficulty in waking up or staying awake, a return of walking difficulties, mild dementia or incontinence. Fortunately, most complications can be handled successfully The symptoms of hydrocephalus tend to vary greatly from person to person and across different age groups. Infants and young children are more susceptible to symptoms from increased intracranial pressure like vomiting and adults can experience loss of function like walking or thinking The following symptoms are considered hallmarks of normal pressure hydrocephalus: Difficulty walking that's sometimes compared to the way a person walks on a boat, with the body bent forward, legs held wide apart and feet moving as if they're glued to the deck These are possible symptoms of NPH: Trouble walking (feels like the feet are stuck to the ground

Hydrocephalus is a condition that occurs when fluid builds up in the skull and causes the brain to swell. The name means water on the brain. Brain damage can occur as a result of the fluid.. Other symptoms include abnormal gait (difficulty walking), inability to hold urine (urinary incontinence), and, occasionally, inability to control the bowels. The dementia symptoms of NPH can be.. Hydrocephalus is a condition of excess fluid on the brain. The brain and spinal cord are normally bathed by cerebrospinal fluid (CSF) which gives the brain buoyancy and acts as a shock-absorber to protect these delicate structures What is hydrocephalus? Hydrocephalus is a condition in which there is excessive fluid in and around the brain. It occurs from a lack of absorption, blockage of flow, or overproduction of the cerebral spinal fluid (CSF) that's made inside the ventricles. The ventricles are fluid-filled areas of the brain Hydrocephalus, or water on the brain, is a condition where a buildup of cerebrospinal fluid in the brain causes increased pressure in the skull. It can be present at birth or develop later in life

The most common symptoms of hydrocephalus vary depending on the age of onset. In infants, symptoms include: A large head that is growing too rapidly A bulging soft spot on top of head (anterior fontanelle Recurrence of any of the initial hydrocephalus symptoms; Other treatments. Some people with hydrocephalus, particularly children, may need additional treatment, depending on the severity of long-term complications of hydrocephalus. A care team for children may include a: Pediatrician or physiatrist, who oversees the treatment plan and medical car The name for this condition, normal pressure hydrocephalus, originates from Dr. Salomon Hakim's 1964 paper describing certain cases of hydrocephalus in which a triad (a group of three) of neurologic symptoms occurred in the presence of 'normal' CSF pressure - gait disturbances (which is usually the first sign), dementia, and impaired bladder control

Normal pressure hydrocephalus (NPH) is a condition that is caused by an abnormal build up of cerebrospinal fluid (CSF) in the ventricles (cavities or spaces) of the brain. Cerebrospinal fluid is a clear liquid that circulates around the brain and spinal cord, cushioning and protecting them from damage Hydrocephalus is a condition where there is excessive accumulation of cerebrospinal fluid in the brain leading to increased intracranial pressure. In infants, a rapid increase in head size may be seen. It is a condition that can be acquired or due to birth defects such as neural tube defects that causes aqueductal stenosis Hydrocephalus and Insomnia. Hydrocephalus can be the cause of headaches as well as some loss of both coordination and balance, seizures, and impaired vision. Another of the physical symptoms is also sleepiness, although many have difficulty falling and staying asleep due to headaches or pain. Insomnia and hydrocephalus feed off of each other. Hydrocephalus is a condition characterized by an abnormal accumulation of cerebrospinal fluid (CSF) within the ventricles of the brain. CSF surrounds the brain and spinal cord. When the circulatory path of the CSF is blocked, fluid begins to accumulate, causing the ventricles to enlarge and the pressure inside the head to increase, resulting in hydrocephalus Symptoms of hydrocephalus. The most common symptoms of hydrocephalus are headache, nausea, vomiting and fits. For babies, hydrocephalus can also cause: increased head size. bulging or firm fontanelle, which is the soft spot on a baby's head. poor feeding. drowsiness or sleepiness. eye turning inwards. seizures

They can include: A full or bulging soft spot on the top of your baby's head (fontanel) Increasing head size (circumference

Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull. Older people may have headaches, double vision, poor balance, urinary incontinence, personality changes, or mental impairment Patients with hydrocephalus can clinically present with nausea, vomiting, headache, papilledema, obtundation, dementia, ataxia, and/or urinary incontinence. The diagnosis is based on clinical.

Normal pressure hydrocephalus (NPH) is an abnormal buildup of cerebrospinal fluid (CSF) in the brain's ventricles, or cavities. It occurs if the normal flow of CSF throughout the brain and spinal cord is blocked in some way Hydrocephalus is a condition where cerebrospinal fluid builds up in a dog's skull, putting pressure on the brain. It is also sometimes referred to as water on the brain. Here's what you should know Symptoms of acquired hydrocephalus vary, depending on age, the severity of the disease, and your tolerance level for this condition. In infants, the most pronounced sign of acquired hydrocephalus is an abnormally large head. In older children, symptoms may include vision problems, headache, nausea, problems walking, and a downward deviation of. Hydrocephalus Symptoms. The following are the most common symptoms of hydrocephalus in babies. However, each baby may experience symptoms differently. Symptoms may include: A full or bulging fontanel (soft spot located on the top of the head) Increasing head circumference (size) Seizure

Hydrocephalus has several types: 1. Congenital Hydrocephalus - There is an excess of CSF accumulation at birth. It might be the result of any infection or trauma during fetal development. 2. Acquired Hydrocephalus - This develops after birth, usually caused by stroke, brain tumor, cyst, or meningitis Generally, the symptoms of hydrocephalus may vary depending on some factors. However, the commonly noted symptoms include the following: Increased head circumference - This is especially true among infants. Among the common findings in infants with hydrocephalus is the gradual increase in the head circumference. Nausea/Vomiting Signs and Symptoms of Hydrocephalus. The signs and symptoms of hydrocephalus will differ among individuals based on a number of factors such as the progression of the disease, the age of the patient and response to treatment and the condition itself. The most common sign is the increase in head size or circumference

Hydrocephalus - Symptoms and causes - Mayo Clini

  1. Hydrocephalus can recur: Nevertheless, surgical procedures successfully cut down the symptoms and let the infant manage hydrocephalus comfortably for the rest of the life. Surgical procedures have limitations: A ventriculostomy procedure works only if the swelling is caused by blockage of ventricles
  2. What are the signs and symptoms of hydrocephalus? Infants and young children: The most common sign is a rapid increase in head size. The head size increases because the bones of a baby's skull have not yet fused together. Other signs and symptoms include the following: Eyes that are turned downward; Bulging fontanelles (soft spots of the head
  3. Hydrocephalus is a buildup of fluid in the brain, or more precisely, cerebrospinal fluid in the ventricular system, which causes potentially damaging increased pressure in the head. Most children who have it are born with it. It occurs in one or two per 1,000 live births
  4. ation and radiologic findings; (2) use of appropriate tests to deter

Symptoms of hydrocephalus in children include sleepiness, blurred or double vision, sleepiness, delayed developmental milestones, poor learning at school, seizures, abnormal sensory-motor functions, and 'setting sun' eyes. There might be a change in personality, and the child may have a problem in previously acquired activities such as. Acquired hydrocephalus occurs after birth when a tumor, injury or disease blocks the absorption of cerebrospinal fluid in the brain. Babies may also be born with hydrocephalus, called congenital hydrocephalus. Affecting one out of every 1,000 newborns, congenital hydrocephalus is caused by a brain malformation or birth defect

Unfortunately, several other things can cause these symptoms, as well. Normal pressure hydrocephalus can be a result of head trauma, an infection or complications of surgery. People also can develop normal pressure hydrocephalus for no obvious reason, and that was the case for Dorothy From a population-based series of children with Infantile Hydrocephalus (IH) 69 patients (mean age 11.7 years) were examined with respect to the occurrence of autistic symptoms. Autistic symptomatology was evaluated according to a modified short Swedish version of the so-called Autism Behavior Check

Hydrocephalus symptoms. Symptoms of hydrocephalus vary with age, disease progression, and individual differences in tolerance to the condition. For example, an infant's ability to compensate for increased CSF pressure and enlargement of the ventricles differs from an adult's Symptoms of normal pressure hydrocephalus include, problems with walking, impaired bladder control leading to urinary frequency and/or incontinence, and progressive mental impairment and dementia. An individual with this type of hydrocephalus may have a general slowing of movements or may complain that his or her feet feel stuck

Hydrocephalus (pronounced hi-dro-SEF-a-lus) is a harmful buildup of cerebrospinal fluid (CSF) in the ventricles of your child's brain. CSF is a clear fluid that bathes and protects your child's brain and spinal cord.Ventricles are the spaces in the brain where CSF is made Normal pressure hydrocephalus (NPH) is a neurological disorder that causes dementia. It's characterized by walking abnormalities, dementia, and impaired bladder control. NPH is relatively rare

Hydrocephalus Fact Sheet National Institute of

Hydrocephalus - Symptoms - NH

  1. Symptoms that can be associated with hydrocephalus include headache, vomiting, blurred or double vision, problems with balance, coordination, and walking, nerve damage, urinary incontinence, fatigue, drowsiness, loss of memory, difficulty thinking, irritability, and changes in personality
  2. Hydrocephalus — also called water on the brain — is a term used to describe several different problems that cause cerebrospinal fluid (CSF) to build up in or around the brain or to drain improperly. This causes the brain's ventricles (fluid spaces inside the brain) to enlarge. a blockage in the brain's anatomy stops the fluid from.
  3. Normal pressure hydrocephalus (NPH) is a type of dementia caused by a buildup of cerebrospinal fluid in the ventricles of the brain. This fluid buildup leads ventricles to enlarge and eventually damages surrounding brain tissue, leading to cognitive impairment and symptoms like loss of bladder control and difficulty walking
  4. Normal pressure hydrocephalus (NPH), despite its name, is an abnormal condition. It occurs in older adults when cerebrospinal fluid (CSF) builds up inside the brain's ventricles. The enlarged areas stretch and damage the brain, causing symptoms of mild dementia, walking difficulties, and urinary problems. NPH often goes untreated because it can.
  5. Congenital hydrocephalus is when a child is born with an excessive accumulation of cerebrospinal fluid (CSF) in the brain. CSF is a clear fluid that surrounds the brain and spinal cord. This excess fluid causes an abnormal widening of spaces in the brain called ventricles (ventriculomegalia) and can create a harmful pressure on brain tissue. Symptoms of hydrocephalus vary and may include an.
  6. Symptoms of Congenital Hydrocephalus. Medical problems associated with congenital hydrocephalus may include: Chiari malformations, an abnormality at the base of the brain where the spinal column joins the skull; Craniosynostosis, when the bones in the skull fuse together before the brain has stopped growin

Hydrocephalus: Symptoms, Causes, Types, Diagnosis, Treatmen

The shunt may relieve other symptoms of normal pressure hydrocephalus, such as an impaired walking ability and loss of bladder control. The best way to prevent dementia from resulting from hydrocephalus is to catch the condition early before the excess fluid build up has a chance to damage the brain tissue Symptoms, Diagnosis, & Treatment of Hydrocephalus. Symptoms of untreated hydrocephalus are variable, and are dependent on a person's age. In cases of prenatal hydrocephalus, routine ultrasounds can detect swollen ventricles in the baby's brain. In children and adults a variety of symptoms can be present and may include the following Normal Pressure Hydrocephalus is much rarer than Alzheimer's disease, affecting about 700,000 Americans compared to more than 5.5 million people with Alzheimer's. NPH also differs from Alzheimer's, and other dementias, because there is a surgical procedure that is successful in lessening symptoms, sometimes significantly Signs and symptoms of hydrocephalus in babies and children can include: fussiness. tiredness. poor appetite. vomiting. eyes that stay looking down. slowed development. Babies younger than 1 year old still have their soft spot because their skull bones have not fully grown together yet. In them, hydrocephalus usually leads to bulging at the.

Symptoms vary depending on the severity of the condition. Cats with moderate to severe hydrocephalus may have oddly dome-shaped skulls or eyes that point outward and downward due to the pressure. Treatment of hydrocephalus will vary depending on how severe the disease is. Neurological symptoms, like seizures, will need to be managed but the amount of CSF also needs to be addressed. A drug called omeprazole is commonly used to decrease CSF but steroids may also be used Symptoms may include redness or tenderness along the shunt tract, sore neck or shoulder muscles and a low-grade fever. Prognosis According to Boston Children's Hospital, the long-term outlook for a child with hydrocephalus depends on early detection, timely treatment of the condition and preventing infection during surgery Congenital hydrocephalus can be caused by a number of factors, including heredity, prenatal infection, exposure to drugs that cause birth defects, and trauma from a difficult birthing process. After birth, they experience fluid buildup, which exerts damaging pressure on the brain. Symptoms and Identificatio Hydrocephalus is an uncommon neurological disorder in dogs. It happens when cerebro-spinal fluid (CSF) cannot drain properly and it increases pressure on the brain. Dogs can be born with hydrocephalus or acquire it as a result of tumors, viral infections, or fungal infections. Treatment depends on the type and cause

Adult-onset Hydrocephalus - Symptoms, Diagnosis and Treatment

  1. Symptoms of hydrocephalus depend on: Age; Amount of brain damage; What is causing the buildup of CSF fluid ; In infants, hydrocephalus causes the fontanelle (soft spot) to bulge and the head to be larger than expected. Early symptoms may also include
  2. Hydrocephalus is a clinical condition characterized by disturbance of cerebrospinal fluid regulation in the central nervous system. Cerebrospinal fluid regulation has three important steps - formation, flow and absorption. Hydrocephalus (Hydrencephalus): Read more about Symptoms, Diagnosis, Treatment, Complications, Causes and Prognosis
  3. Hydrocephalus is a buildup of spinal fluid inside the fluid chambers of the brain. Hydrocephalus means water on the brain. Normal pressure hydrocephalus (NPH) is a rise in the amount of cerebrospinal fluid (CSF) in the brain that affects brain function. However, the pressure of the fluid is usually normal
  4. More. Five to 10 percent of Americans diagnosed with dementia could actually have a treatable condition known as normal pressure hydrocephalus or NPH, according to experts in the field. An.
  5. Symptoms and Signs of Hydrocephalus Neurologic findings depend on whether intracranial pressure is increased, symptoms of which in infants include irritability, high-pitched cry, vomiting, lethargy, strabismus, and bulging fontanelle. Older, verbal children may complain of headache, decreased vision, or both..

Hydrocephalus - Causes, Symptom and Surgical Treatment

  1. Hydrocephalus is a neurological disorder in which excessive amounts of cerebrospinal fluid accumulate in the brain. Cerebrospinal fluid, or CSF, is produced by the normal brain and serves to protect and clean the tissues of the brain. Here's what you should know about this dangerous condition
  2. Pediatric Hydrocephalus. Hydrocephalus literally means water on the brain.. In this case, though, the water is really a fluid that protects the brain. Hydrocephalus occurs when fluid builds up in the ventricles (cavities) deep in the brain, putting extra pressure on the brain. Dallas
  3. Congenital hydrocephalus is a common distinct entity in some toy and brachycephalic breeds (e.g. Boston terrier, cavalier King Charles spaniel, Chihuahua). A commonly identified cause in predisposed breeds is narrowing or blockage of the CSF flow in the ventricular system. Neonatal infections, such as those with viral causes, can result in.
  4. Normal-pressure hydrocephalus (NPH), also called malresorptive hydrocephalus, is form of communicating hydrocephalus in which excess cerebrospinal fluid (CSF) occurs in the ventricles, and with normal or slightly elevated cerebrospinal fluid pressure.As the fluid builds up, it causes the ventricles to enlarge and the pressure inside the head to increase, compressing surrounding brain tissue.

Normal Pressure Hydrocephalus (NPH) Symptoms

The symptoms of normal pressure hydrocephalus usually get worse over time if the condition is not treated, although some people may experience temporary improvements. If left untreated, progressive hydrocephalus is fatal, with rare exceptions. The parents of children with hydrocephalus should be aware that hydrocephalus poses risks to both. The condition of early hydrocephalus occurs when improper drainage occurs in the developing brain of the newborns; the excessive pressure and ventricle swelling results in abnormal enlargement of.

Normal Pressure Hydrocephalus Johns Hopkins Medicin

Symptoms of hydrocephalus depend upon age, and may range from irritability, sleepiness, and poor feeding to vomiting, personality and memory changes, difficulty walking, and urinary incontinence.Treatment is aimed at fixing the cause of the hydrocephalus and relieving the pressure on the brain The most characteristic sign of hydrocephalus in children and infants is often a rapid increase in head circumference or an unusually large head size. Other associated symptoms and signs can include. an abnormality with walking, instability, problems with coordination, stiff muscles, nausea, vomiting, memory loss In hydrocephalus, the head grows much faster in proportion to the child's weight and height. Aside from the large head that increasingly becomes larger, here are the symptoms of hydrocephalus in babies: The soft spot on the baby's head (fontanel) is bulged or tense. Frequent vomiting. High irritability Symptoms of Communicating Hydrocephalus. These are some of the most common symptoms of communicating hydrocephalus: Abnormalities of gait. First symptom. May precede other symptoms (by months or years) Magnetic gait (feet stuck to the floor) Dementia. Varying degrees - from memory impairment to slow thinking Symptoms Of Hydrocephalus. Hydrocephalus is a condition that needs immediate medical attention. The problem can get worse when you ignore the problem. Therefore, it is important to recognize the signs of the issue as soon as possible. Ignoring it can result in irreversible brain damage. People of any age can suffer from the issue

Hydrocephalus: Causes, Symptoms, and Diagnosi

Hydrocephalus : Symptoms, Picture, Causes, and Treatment 2. Hydrocephalus is a disease that is characterized by the build-up of fluid in the skull and this leads to a swelling in the brain. Hydrocephalus means water on the brain. Brain damage can take place as a consequence of fluid retention. This is associated with developmental, intellectual. Clinical features of hydrocephalus. Young adults: Symptoms—headache, vomiting, failing vision, drowsiness, muzziness of the head, fatigue. Signs—papilloedema, enlarged blind spots on visual field analysis or reduced visual acuity, failure of upward gaze, general clumsiness, dyspraxic gait, large head. Older adults/elderly The symptoms of normal pressure hydrocephalus usually get worse over time if the condition is not treated, although some people may experience temporary improvements. While the success of treatment with shunts varies from person to person, some people recover almost completely after treatment and have a good quality of life

Hydrocephalus: Causes, Symptoms, and Treatmen

Hydrocephalus may be caused by a blockage of the normal flow of CSF, a failure of absorption of CSF, or least commonly, an overproduction of CSF. Communicating hydrocephalus occurs when the flow of CSF is blocked after it exits the cerebral ventricles. Noncommunicating hydrocephalus occurs when there is a blockage rostral to the lateral. Normal pressure hydrocephalus is thought to be incurable, and I was told I would have to have a shunt in my brain for the rest of my life to drain the excess fluid. But before we go into how I cured myself, I'd like to talk about symptoms I had that I didn't know were early warning signs and symptoms of hydrocephalus Hydrocephalus is a chronic and neurological disease caused by the over-accumulation of cerebrospinal fluid. It can be seen at any age, including newborns. Pressure inside the skull causes many problems. Potential brain damage occurring as a result of fluid accumulation may cause developmental, physical and mental deterioration

Hydrocephalus Disease Symptoms, Causes and Treatments

Hydrocephalus causes various combinations of the above listed symptoms and signs, dependent on the causes and that also vary with age. For instance, a problem referred to as normal pressure hydrocephalus that mainly affects individuals who are older - typically beginning with problems walking When hydrocephalus begins in an adolescent or a young adult, the facial abnormalities are less obvious than in children with congenital or early onset hydrocephalus. Many of the other mental and physiologic symptoms are the same; however, previously acquired skills requiring coordinated movement (motor coordination) may be lost This type of hydrocephalus usually occurs in older adults. Symptoms of NPH can be characterized by the gradual onset of three symptoms, usually in this order: Gait disturbance (difficulty walking) in the form of small shuffling steps, a tendency to fall, a feeling of heavy feet, or difficulty using stairs. Urinary incontinence (impaired bladder. If the aqueduct is mostly or completely blocked, the child will likely experience symptoms and be diagnosed with hydrocephalus at an early age. If, however, the aqueduct is only a little narrower than normal, the child may go through life without any symptoms of hydrocephalus Normal pressure hydrocephalus (NPH) is a condition with an abnormally high amount of cerebrospinal fluid in the brain's ventricles (cavities). NPH is rare, occurring in 1 of 100,000 people. People of any age can have it, but it occurs most often in elderly people

Pediatric Hydrocephalus - Conditions and Treatments

The brain imaging of communicating hydrocephalus typically demonstrates dilation of all the ventricles of the brain and infrequently the subarachnoid space. Patients with postmeningitic hydrocephalus are a typical example. The signs and symptoms of hydrocephalus are age dependent and often relate to the rapidity of the ventricular expansion Symptoms of hydrocephalus in adults vary somewhat depending on the underlying cause. However, in general, common symptoms, regardless of cause, can include headaches, nausea and vomiting, lethargy and somnolence and eventually decline in visual function. Other neurological symptoms that can occur in some patients include abnormalities of the. The signs and symptoms of the condition vary depending on the age of onset. Typically, hydrocephalus in infants causes symptoms including an unusually large head, a bulging or tense spot on top of the head, vomiting, excessive sleepiness, irritability, poor feeding and seizures. The condition in toddlers and older children presents symptoms.

Hydrocephalus: Causes, symptoms, and treatment

10 Hydrocephalus Symptoms. By jolene. Reviewed: Dr. Gromatzky. Article Sources. Medical Expert. More About Us. Symptom #2: Nausea. Nausea refers to an unpleasant and uncomfortable sensation where there is an urge to vomit. Although nausea does not result in pain, it can be a debilitating issue as there is discomfort that can be felt in the. Removing CSF to Diagnose Normal Pressure Hydrocephalus . The gold standard of diagnosing NPH is an improvement of symptoms with ventricular shunting. This standard is practically useless, though, since in order to recommend a risky procedure like shunt placement the doctor must already be highly confident that the patient has NPH A shunt redirects cerebrospinal fluid from the nervous system to another area of the body. This technique allows the brain's enlarged ventricles to return to a more normal size in an effort to relieve the symptoms of hydrocephalus. A shunt is designed to What is hydrocephalus? Hydrocephalus is disorder in which the ventricular system in the brain contains an excessive amount of cerebrospinal fluid (CSF). Obstructive hydrocephalus is due to an obstruction blocking the flow of CSF. Communicating hydrocephalus is due to impaired resorption of CSF. Common symptoms reported by people with hydrocephalus

Symptoms of Hydrocephalus. In children, the symptoms vary based on the age of the child. In infants, the symptoms are as follows: A rapid increase in the size of the head results in an unusually. Common signs and symptoms of MPPH syndrome include polymicrogyria, megalencephaly, intellectual disability, seizures, polydactyly, and hydrocephalus. Additional signs and symptoms reported in the medical literature include thin corpus callosum, psychomotor impairment (i.e., slowing down of physical reactions, movements, and speech), impaired. Symptoms. NPH occurs most often in older adults, or as the result of a traumatic injury or illness. Its negative effect on cognition and movement often mimics other conditions such as Alzheimer's or Parkinson's disease. Without the right diagnosis, these symptoms of normal pressure hydrocephalus can mistakenly be attributed to the aging. Recognizing normal pressure hydrocephalus in older adults. Smith, Carolyn E. MS, RN, CNRN. Author Information. In York, Pa., Carolyn E. Smith is a clinical nurse at Wellspan York Hospital and adjunct nursing faculty at York College of Pennsylvania. The author and planners have disclosed no potential conflicts of interest, financial or otherwise Causes of Hydrocephalus. 1) impaired absorption of CSF fluid w/in the subarachnoid space, obliteration of of the subarachnoid cisterns, or malfunction of the arachnoid villi (nonobstructive) 2) obstruction to the flow of CSF through the ventricular system. Developmental Defects