Brain Sagging Dementia—Diagnosis, Treatment, and Outcome

Abstract

Brain sagging dementia (BSD), caused by spontaneous intracranial hypotension (SIH), is a rare syndrome that is only recently recognized, mimicking the clinical findings of behavioral variant frontotemporal dementia (bvFTD). Being aware of its signs and symptoms is essential for early diagnosis and treatment in this potentially reversible form of dementia. Our objective was to identify cases with BSD in the literature and present its clinical characteristics, diagnostic workup, treatment options, and outcome.The review was reported according to PRISMA guidelines and registered with the PROSPERO database (CRD42020150709). MEDLINE, EMBASE, PsychINFO, and Cochrane Library were searched. There was no date restriction. The search was updated in April 2021.A total of 983 articles were screened and assessed for eligibility. Twenty-nine articles (25 case reports and four series) and 70 patients were selected for inclusion. No cranial leak cases were identified. BSD diagnosis should be made based on clinical signs and symptoms and radiological findings. There is a male predominance (F: M ratio 1:4) and a peak incidence in the 6th decade of life. The main clinical manifestation is insidious onset, gradually progressive cognitive and behavioral changes characteristic for bvFTD. Headache is present in the majority of patients (89%). The presence of brain sagging and absence of frontotemporal atrophy is an absolute criterion for the diagnosis. The CSF leak is identified with myelography and digital subtraction myelography. The treatment and repair depend on the etiology and extent of the dural defect, although an epidural blood patch is the first-line treatment in most cases. With treatment, 81% experienced partial and 67% complete resolution of their symptoms. This review highlights the most important clinical aspects of BSD. Due to the sparse evidence and lack of BSD awareness, many patients are most likely left undiagnosed. Recognizing this condition is essential to provide early treatment to reverse the cognitive and behavioral changes that may otherwise progress and fully impair the patient. Moreover, patients with longstanding SIH must be carefully assessed for cognitive and behavioral changes.

The first report on brain sagging dementia caused by a cranial leak: A case report

“…The constellation of signs and symptoms of frontotemporal dementia caused by SIH, known as brain sagging dementia (BSD), has been increasingly recognized recently ( 7 – 9 ). The condition is twice as common in male patients and peaks in the sixth decade of life ( 3 ). Like in SIH, most patients present with some form of headache.…”

“…Although a spinal CSF leakage is thought to be the etiology behind SIH and BSD, it is not radiologically evident in a significant number of patients ( 3 , 4 ). In a recent review on BSD, a CSF leakage site was found in merely 13% of cases ( 3 ). Moreover, no cranial leak was reported in the two largest reviews on SIH and BSD ( 3 , 4 ).…”

“…In a recent review on BSD, a CSF leakage site was found in merely 13% of cases ( 3 ). Moreover, no cranial leak was reported in the two largest reviews on SIH and BSD ( 3 , 4 ). Thus, this is the first report on a case of BSD caused by a cranial CSF leak.…”

“…Brain sagging dementia (BSD) is a rare syndrome that results in behavioral and cognitive changes mimicking behavioral variant frontotemporal dementia (bvFTD) ( 1 , 2 ). Spontaneous intracranial hypotension (SIH) caused by cerebrospinal fluid (CSF) leakage is thought to be the cause, however, no cranial leaks have been reported ( 3 , 4 ). We present the first report on a patient fulfilling the recently proposed BSD diagnostic criteria ( 3 ), caused by a cranial CSF leakage.…”

“…Spontaneous intracranial hypotension (SIH) caused by cerebrospinal fluid (CSF) leakage is thought to be the cause, however, no cranial leaks have been reported ( 3 , 4 ). We present the first report on a patient fulfilling the recently proposed BSD diagnostic criteria ( 3 ), caused by a cranial CSF leakage.…”