Programable Ventriculoperitoneal (VP) shunt

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What is a Shunt?

The most common treatment for hydrocephalus is the surgical placement of a medical device called a shunt. A shunt, in its simplest form, is a flexible tube called a catheter, which is placed into the area of the brain where cerebrospinal fluid (CSF) is produced. This area of the brain is known as the lateral ventricles. The tubing is then passed under the skin to another region of the body, most often the abdominal cavity, or heart, diverting the excess CSF away from the brain, where it can be absorbed naturally by the body. By draining the extra fluid to another location in the body, it is relieving pressure on the brain.

A shunt consists of three major components:

  • An inflow or proximal catheter, which drains CSF from the lateral ventricles. This tube leaves the brain through a small hole drilled in the skull and then runs for a short distance under the skin.

  • A valve mechanism, which regulates intracranial pressure by controlling fluid flow through the shunt tubing. This device is connected to the proximal catheter and lies between the skin and the skull, usually on top or the back of the head, or just behind the ear. Valves operate within a specific pressure range. There are many types of valves and shunt manufacturers. Your doctor will determine the type of valve based on his/her experience, preference, and your needs.

  • An outflow or distal catheter, which runs under the skin and directs CSF from the valve to the abdominal (peritoneal) cavity, heart or another suitable drainage site.

Ventriculoperitoneal (VP) shunts. This type of shunt diverts CSF from the ventricles of the brain into the peritoneal cavity, the space in the abdomen where the digestive organs are located. The tip of the distal catheter rests in this cavity near the loops of the intestine and bowel but not inside them. The CSF shunted to this area is reabsorbed into the bloodstream and is eventually excreted through normal urination.

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Adjustable (programmable) valves regulate the ICP based on a pressure setting, like the fixed pressure valve, but the setting can be adjusted by your doctor using an external adjustment tool applied outside the body if there needs to be a change in how much CSF is draining. This allows your health care professional to non-invasively change or program the valve pressure setting during an office visit. The number of available settings depends on the valve model and manufacturer.

These valves are designed to be adjusted by a strong magnetic field found in the external adjustment tool. Some of these valves may be susceptible to adjustment by strong environmental magnetic fields and care must be taken to keep toys with magnets and other sources of magnetic fields away from the implanted device. Some adjustable valves incorporate mechanisms that cannot be adjusted by magnetic fields other than those produced by the programmer. It’s important to ask your doctor what precautionary measures should be taken.

on the subject of quarantine of those ACTUALLY sick (not those assumed to be sick)

Quarantine and other public health practices are effective and valuable ways to control communicable disease outbreaks and public anxiety, but these strategies have always been much debated, perceived as intrusive, and accompanied in every age and under all political regimes by an undercurrent of suspicion, distrust, and riots. These strategic measures have raised (and continue to raise) a variety of political, economic, social, and ethical issues. In the face of a dramatic health crisis, individual rights have often been trampled in the name of public good. The use of segregation or isolation to separate persons suspected of being infected has frequently violated the liberty of outwardly healthy persons, most often from lower classes, and ethnic and marginalized minority groups have been stigmatized and have faced discrimination. This feature, almost inherent in quarantine, traces a line of continuity from the time of plague to the 2009 influenza A(H1N1)pdm09 pandemic.

Idiopathic Normal Pressure Hydrocephalus (INPH

Spaces in the brain, called ventricles, where excess cerebrospinal fluid can build up, causing NPH.

Spaces in the brain, called ventricles, where excess cerebrospinal fluid can build up, causing NPH.

Idiopathic normal pressure hydrocephalus (INPH) is a treatable cause of gait disturbance, cognitive impairment, and urinary incontinence… Not all INPH patients exhibit clinical improvement after shunting, and it is challenging to identify patients who are more likely to benefit from shunting.

…discrepancies in treatment outcomes are the result of controversies in 3 distinct but interrelated domains: the underlying pathophysiology of INPH, the diagnosis of INPH, and the identification of likely shunt-responders.

…shunting is a safe and effective means of achieving meaningful clinical improvement in most patients with INPH.

…Normal pressure hydrocephalus (NPH) was first reported in 1965 as a triad of dementia, gait disturbance, and urinary incontinence, with associated ventricular dilatation and normal cerebrospinal fluid (CSF) pressure.

…NPH can be classified as idiopathic NPH (INPH) or secondary NPH (SNPH), the latter of which occurs most commonly after subarachnoid hemorrhage, trauma, or meningitis.

…surgical outcomes in INPH have been consistently less successful than those in SNPH.

…the reported rates of postoperative clinical improvement in INPH patients have varied from 24% to 96%.

…INPH typically occurs during the seventh decade of life.

…the prevalence is from 0.41% to 1.4% for persons aged 65 years or older.

…To date, no clear pathophysiological mechanism for INPH has been established.

…CSF diversion can improve INPH symptoms

…In their cohort of 93 patients with INPH, 65% of the immediate surgery group demonstrated an improvement in modified Rankin scale of at least 1 point at 3 months compared with 5% in the postponed treatment group.

Cerebrospinal fluid diversion is a procedure that is used to drain fluid from the brain and spinal cord. A shunt is placed in a ventricle of the brain and threaded under the skin to another part of the body, usually the abdomen. It is used to treat hydrocephalus and idiopathic intracranial hypertension.

…Diagnosing INPH is difficult, and the accepted gold standard for diagnosis is clinical improvement after shunt surgery. This implies a circular argument: shunt-responsive INPH (SR-INPH) is defined by a clinical response to CSF diversion.

…INPH is characterized by a slow, short-stepped shuffling with a slightly broad base, reduced step-height, and associated gait freezing. …It may also include postural instability and difficulty turning. These gait disturbances are consistent with subcortical deficits involving the basal ganglia and frontal periventricular pathways.

Although INPH was originally reported as a reversible dementia, dementia is in fact the triad symptom least likely to improve postoperatively. The typical cognitive deficits of INPH are “subcortical,” with psychomotor retardation, apathy, difficulty in executive functions, and impaired recall memory yet relatively preserved recognition memory.

Urinary symptoms in INPH usually begin as increased frequency and urgency, only developing into incontinence in later stages. Urinary symptoms respond well to shunting but only predict a functional improvement in 31% to 33% of patients.

Despite classically being a triad of symptoms, INPH can be diagnosed in the presence of gait disturbance and 1 other cardinal symptom. This is in light of findings revealing that the complete triad often represents prolonged symptom duration, more advanced disease, and a poorer prognosis.

…Neuroimaging evidence of hydrocephalus on computerized tomography (CT) or magnetic resonance imaging (MRI) is essential for the diagnosis of INPH.

…Much of the diagnostic uncertainty surrounding INPH relates to difficulties distinguishing INPH from other diagnoses common in the elderly. It is also important to note that multiple comorbidities are common in the elderly and can mimic INPH…

…Programmable valves have now been adopted, as they permit noninvasive pressure adjustments that can optimize clinical improvement and ameliorate drainage-related complications.

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Overall, shunt-related complications occur in up to 38% of patients, 22% require additional surgery, and there is a 6% rate of permanent neurological deficit or death. Common complications include shunt malfunctions, infections, headaches, and drainage-related subdural hematomas or effusions.

A systematic review of 64 outcome studies demonstrated that 71% (range, 28%–100%) of patients with INPH had a positive outcome at 1 year after shunt insertion and that 65% (range, 31%–96%) demonstrated improvement beyond 3 years.

…the duration of postoperative follow-up necessary to adequately assess clinical status has not been established. For example, the Dutch NPH study restricted the follow-up period to 1 year, whereas other studies have demonstrated that some INPH patients still continue to improve at 24 months. On the other hand, studies that have followed patients for 3 years or more have consistently found declining rates of clinical improvement.However, long-term outcomes also undoubtedly are influenced by comorbidities, and vascular factors have been shown to be a main cause of mortality.

before proceedure

after proceedure

before proceedure

after proceedure

After 50 years of research, the diagnosis and treatment of INPH seems to have improved. …both the accurate diagnosis of INPH and the appropriate selection of shunt surgery candidates remain controversial issues. Those familiar with the condition can diagnose it, and most patients so diagnosed obtain meaningful clinical improvement.

non-pharmaceutical public health measures for mitigating the risk and impact of epidemic and pandemic influenza

Face masks for symptomatic individuals

OVERALL RESULT OF EVIDENCE ON FACE MASKS

1. Ten RCTs were included in the meta-analysis, and there was no evidence that face masks are effective in reducing transmission of laboratory-confirmed influenza.

WHO thought this was a good idea?

WHO gives new, “simpler” names to variants

  • Gods, invented names were also considered

  • Geographical names lead to stigma, WHO says

GENEVA, May 31 (Reuters) - Coronavirus variants with clunky, alphanumeric names have now been assigned the letters of the Greek alphabet to simplify discussion and pronunciation while avoiding stigma.

(Please. Stop with the greek letter designations.)

Pango is your friend

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The Pango nomenclature is being used by researchers and public health agencies worldwide to track the transmission and spread of SARS-CoV-2, including variants of concern. This website documents all current Pango lineages and their spread, as well as various software tools which can be used by researchers to perform analyses on SARS-COV-2 sequence data.

Each coronavirus contains nearly 30,000 letters of RNA. This genetic information allows the virus to infect cells and hijack them to make new viruses.

All viruses, including SARS-CoV-2, the virus that causes COVID-19, change over time. Most changes have little to no impact on the virus’ properties. However, some changes may affect the virus’s properties, such as how easily it spreads, the associated disease severity, or the performance of vaccines, therapeutic medicines, diagnostic tools, or other public health and social measures.