Utjecaj položaja tijela na volumen cerebrospinalnoga likvora u kranijskom i spinalnom prostoru

doctoral thesis

• Title (english): The effect of body position on cerebrospinal fluid volume in the cranial and spinal compartments
• Author: Ines Strbačko
• Mentor: Milan Radoš (mentor)
• Committee member: Marko Radoš (predsjednik povjerenstva)
• Committee member: Boris Brkljačić (član povjerenstva)
• Committee member: Darko Chudy (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; Zagreb
• Defense date and country: 2023-06-07, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Neurology
• Universal decimal classification (UDC): 61 - Medical sciences

Abstract

Unatoč tome što kraniospinalni likvorski sustav čini jedinstvenu funkcionalnu cjelinu,
većina istraživačkih studija ograničena je na analizu samo kranijskog likvorskog prostora i to
u horizontalnom položaju, iako većinu svog života provodimo u uspravnom položaju (stojećem
ili sjedećem). U prethodnim radovima naše istraživačke skupine pokazali smo kako kod
podizanja iz horizontalnog u uspravni položaj intrakranijski tlak cerebrospinalnog likvora pada
na subatmosferske vrijednosti sukladno zakonu o mehanici fluida te da promjene
intrakranijskog tlaka nisu nužno povezane i s promjenom intrakranijskog volumena kako se to
pretpostavlja prema klasičnoj hipotezi o fiziologiji likvora. U našem istraživanju proučavali
smo kako promjena položaja tijela utječe na volumene likvora u kranijskom i spinalnom dijelu
likvorskog sustava. Zdravi dobrovoljci oba spola prosječne dobi 25 godina snimljeni su
magnetskom rezonancijom u tri različita položaja - u horizontalnom položaju, položaju s
uzdignutom glavom i gornjim dijelom trupa te položaju s uzdignutim donjim dijelom trupa, te
su potom izračunati kranijski i spinalni volumeni likvora metodama automatske segmentacije
za kranijski dio te poluautomatske segmentacije za spinalni dio likvorskog sustava.
Usporedbom volumena likvora između različitih položaja, rezultati naše studije pokazuju kako
su vrijednosti ukupnog volumena likvora značajno veće nego što se navode u literaturi i
udžbenicima te kako promjene položaja tijela ne dovode do značajnog pomaka likvora između
kranijskog i spinalnog prostora kako se do sada smatralo, nego prvenstveno izazivaju
redistribuciju likvora unutar spinalnog likvorskog prostora i to u prvom redu u
lumbosakralnom segmentu. Naše istraživanje doprinosi boljem razumijevanju fiziologije
likvora što je od presudne važnosti za liječenje brojnih kliničkih stanja kod kojih se javljaju
promjene volumena i/ili tlaka unutar kranijskog i spinalnog likvorskog sustava.

Abstract (english)

Despite the fact that the craniospinal cerebrospinal fluid system forms a unique functional
entity, most research studies are limited to analyzing only the cranial cerebrospinal fluid space
and in a horizontal position, even though we spend most of our lives in an upright position
(standing or sitting). We have showed in our previous studies that a transition from a horizontal
to a vertical position lowers the intracranial pressure of the cerebrospinal fluid (CSF) to a
subatmospheric value in accordance with the law of fluid mechanics and that changes in the
intracranial pressure are not necessarily associated with a change of the intracranial volume as
it is assumed by the classical hypothesis of CSF physiology. In our research, we studied how
the change in body position affects the volume of the cerebrospinal fluid in the cranial and
spinal parts of the cerebrospinal fluid system. Healthy volunteers of both sexes with an average
age of 25 years were scanned in MRI in three different positions - in a horizontal position, a
position with the head and upper body raised, and a position with the lower body raised;
subsequently the cranial and spinal cerebrospinal fluid volumes were calculated using
automatic segmentation methods for the cranial part and semi-automatic segmentation for the
spinal part of the cerebrospinal fluid system. By comparing the volume of the cerebrospinal
fluid between different positions, the results of our study show that the values of the total
volume of the cerebrospinal fluid are significantly higher than reported in the literature and
textbooks, and that changes in body position do not lead to a significant shift of the
cerebrospinal fluid between the cranial and spinal spaces, as previously thought, but they
primarily cause the redistribution of the cerebrospinal fluid within the spinal cerebrospinal
fluid space, and primarily in the lumbosacral segment. Our research contributes to a better
understanding of the physiology of the cerebrospinal fluid, which is of crucial importance for
the treatment of numerous clinical conditions in which changes in volume and/or pressure
occur within the cranial and spinal cerebrospinal fluid systems.

• Keywords: cerebrospinalni likvor; volumen likvora; položaj tijela; magnetska rezonancija; segmentacija; volumetrija
• Keywords (english): cerebrospinal fluid; CSF volume; body position; magnetic resonance imaging; segmentation; volumetry
• Language: croatian
• URN:NBN: urn:nbn:hr:105:959713
• Study programme: Title: Neuroscience; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje biomedicine i zdravstva (doktor/doktorica znanosti, područje biomedicine i zdravstva)
• Type of resource: Text
• Extent: 114 str.
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-07-07 09:26:39