Overview: Some patients diagnosed with behavioral variant frontotemporal dementia (eg-FTD) may instead suffer from a cerebrospinal fluid leak that leads to brain prolapse.
Source: Cedars Sinai Medical Center
A new Cedars-Sinai study suggests that some patients diagnosed with behavioral variant frontotemporal dementia (bvFTD) — an incurable condition that robs patients of the ability to control their behavior and cope with everyday life — instead have a cerebrospinal fluid leak. can have. often treatable.
Researchers say these findings, published in the peer-reviewed journal Alzheimer’s and dementia: translational research and clinical interventionscan point the way to healing.
“Many of these patients experience cognitive, behavioral and personality changes so severe they are arrested or placed in nursing homes,” said Wouter Schievink, MD, director of the Cerebrospinal Fluid Leak and Microvascular Neurosurgery Program and professor of Neurosurgery at Cedars-Sinai .
“If they have behavioral variant frontotemporal dementia of unknown cause, then there is no treatment available. But our study shows that patients with cerebrospinal fluid leakage can be cured if we can find the source of the leak.”
Cerebrospinal fluid (CSF) circulates in and around the brain and spinal cord to help protect them from injury. When this fluid leaks into the body, the brain can prolapse, causing dementia symptoms. Schievink said that many patients with cerebral palsy — which can be detected by MRI — go undiagnosed, and he advises clinicians to take another look at patients with telltale symptoms.
“A knowledgeable radiologist, neurosurgeon or neurologist should recheck the patient’s MRI to make sure there is no evidence of cerebral palsy,” Schievink said.
Doctors may also ask about a history of severe headaches that improve when the patient lies down, significant drowsiness even after getting enough sleep, and whether the patient has ever been diagnosed with a Chiari malformation, a condition in which brain tissue extends into the spine. channel. Brain prolapse, Schievink said, is often mistaken for a Chiari malformation.
Even when brain prolapse is detected, the source of a CSF leak can be difficult to pinpoint. When the fluid leaks through a tear or cyst into the surrounding membrane, it is visible on CT myelogram imaging using contrast medium.
Schievink and his team recently discovered another cause of CSF leakage: the CSF venous fistula. In these cases, the fluid leaks into a vein, making it difficult to see on a routine CT myelogram. To detect these leaks, technicians must use a specialized CT scan and observe the contrast agent in motion as it flows through the cerebrospinal fluid.
In this study, researchers used this imaging technique on 21 patients with cerebral palsy and symptoms of bvFTD, and they detected CSF venous fistulas in nine of those patients. All nine patients had their fistulas surgically closed and their brain prolapse and associated symptoms were completely reversed.
“This is a rapidly evolving field of study, and advances in imaging technology have significantly improved our ability to detect sources of CSF leakage, especially CSF venous fistula,” said Keith L. Black, MD, chair of the Department of Neurosurgery and the Ruth and Lawrence Harvey Chair in Neuroscience at Cedars-Sinai.
“This specialized imaging is not widely available, and this study suggests the need for further research to improve detection and cure rates for patients.”
The remaining 12 study participants, whose leaks could not be identified, were treated with non-targeted therapies designed to relieve cerebral palsy, such as implantable systems to infuse the patient with CSF. However, only three of these patients experienced relief from their symptoms.
“Major efforts should be made to improve the detection rate of CSF leakage in these patients,” Schievink said.
“We have developed non-targeted treatments for patients whose leak cannot be detected, but as our research shows, these treatments are much less effective than targeted, surgical correction of the leak.”
About this dementia research news
Writer: Press Office
Source: Cedars Sinai Medical Center
Contact: Press Service – Cedars Sinai Medical Center
Image: The image is in the public domain
Original research: Open access.
“The reversible disorder of behavioral variant frontotemporal brain relaxation syndrome: challenges and opportunities” by Wouter I. Schievink et al. Alzheimer’s and dementia: translational research and clinical interventions
The reversible disorder of behavioral variant frontotemporal brain relaxation syndrome: challenges and opportunities
Due to loss of brain buoyancy, spontaneous leakages of spinal cerebrospinal fluid (CSF) cause orthostatic headaches, but can also cause symptoms indistinguishable from behavioral variant frontotemporal dementia (bvFTD) due to severe cerebral palsy (including the frontal and temporal lobes), as visualized on brain magnetic resonance imaging. However, the detection of these CSF leaks may require specialized spinal imaging techniques such as digital subtraction myelography (DSM).
We performed DSM in the lateral decubitus position under general anesthesia in 21 consecutive patients with brain prolapse syndrome with frontotemporal dementia (4 females and 17 males; mean age 56.2 years (range: 31-70 years)).
Nine patients (42.8%) were found to have a CSF venous fistula, a recently discovered type of CSF leak that cannot be detected on conventional spinal imaging. All nine patients underwent gentle surgical ligation of the fistula. Complete or near complete and sustained resolution of bvFTD symptoms was achieved in all nine patients, accompanied by reversal of cerebral palsy, but in only three (25.0%) of twelve patients in whom no CSF venous fistula could be detected (P = 0.0011), and who were treated with non-targeted therapies.
Concerns about a spinal CSF leak should not be dispelled in patients with frontotemporal brain prolapse syndrome, even when conventional spinal imaging is normal. But even with this specialized imaging, the cause of spinal CSF loss remains elusive in more than half of patients.