Headache Medicine 2021, 12(4):287-292 p-ISSN 2178-7468, e-ISSN 2763-6178
287
ASAA
DOI: 10.48208/HeadacheMed.2021.47
Headache Medicine
© Copyright 2021
Mini-Review
Headache and neuroimaging ndings in conditions of cerebrospinal
uid (CSF) circulation disorders: in hydrocephalus,
pseudotumor
cerebri
, and CSF hypotension syndrome
Maria de Fátima Viana Vasco Aragão
1,2
, Luziany Carvalho Araújo
3
, Marcelo Moraes Valença
1
1
Universidade Federal de Pernambuco, Recife, Brazil
²Centro Diagnóstico Multimagem, Recife, Brazil
³Hospital da Restauração, Recife, Brazil.
Abstract
The authors wish in this narrative minireview show and comment on some neuroimaging
ndings encountered in patients with conditions of cerebrospinal uid (CSF) circulation
disorders, such as in the hydrocephalus, pseudotumor cerebri, and CSF hypotension
syndrome. The MRI of a young woman with a clinical diagnosis of post-dural puncture
headache, performed on the fourth postpartum day after cesarean delivery, evolving with
headache and diplopia, is shown. Non-contrast-enhanced sagittal T1 magnetic resonance
imaging shows that the cerebellar tonsils are at the level of the foramen magnum, therefore
still within normal limits, but, despite that, the opening of the cerebral aqueduct in the
third ventricle is below the imaginary line connecting the anterior clinoid to the vein of
Galen, therefore considered abnormally lower than the expected anatomical position.
The axial T1-weighted images with post-contrast fat suppression also show impregnation
and thickening of the dura mater. There is also mild engorgement of the cerebral venous
sinuses, best demonstrated on T1 with post-contrast fat suppression, which is also identied
on post-contrast magnetic resonance angiography, with no signs of venous thrombosis.
We conclude that the diagnosis of a patient with intracranial hypotension syndrome can
be suspected or conrmed with typical neuroimaging ndings.
Maria de Fátima Viana Vasco Aragão
fatima.vascoaragao@gmail.com
Edited by:
Juliana Ramos de Andrade
Keywords:
Post-Dural Puncture Headache
Intracranial Hypotension
Neuroimaging
Pseudotumor Cerebri
Headache
Received: December 2, 2021
Accepted: December 15, 2021
288
ASAA
Aragão MFVV, Araújo LC, Valença MM
Headache and neuroimaging findings in conditions of cerebrospinal fluid (CSF) circulation disorders: in hydrocephalus, pseudotumor cerebri, and CSF
hypotension syndrome
Introduction
I
n the intracranial cavity we nd three distinct compart-
ments: the brain parenchyma (≅1,300 ml), blood (≅120
ml), and cerebrospinal uid (CSF, ≅120 ml) in normal phy-
siological conditions. According to the Monro-Kellie doc-
trine, the sum of the volumes of these three compartments
is constant.
1-5
The production of CSF is about 0.35 ml/min
(≅500 ml/day), and there is dynamic blood in and outow
(approximately 700 ml/min) regarding the intracranial
space.
6
The only real constant is the brain parenchyma
volume, which is inelastic. Recent studies have observed
changes in these compartments in abnormal situations.
6-10
During the cardiac cycle (systole-diastole), the volume
of the other two compartments varies, with an inverse
relationship between intracranial blood volumes and
intracranial CSF volume. A certain amount of CSF has to
exit at each systole via the foramen magnum to the dural
sac to allow arterial blood to enter the cranial cavity;
without it, there would be no space for more blood inside
the cranial cavity.
The authors wish in this narrative minireview show and
comment on some neuroimaging ndings encountered
in patients with conditions of circulation disorders, such
as in the hydrocephalus,
pseudotumor cerebri
, and CSF
hypotension syndrome.
Hydrocephalus
Patients with hydrocephalus often complain of headache.
The headache pattern will depend on several variables,
such as intracranial hypertension or hypotension, type
of hydrocephalus, associated conditions (
e.g
., tumor,
infection, trauma), age, the position of the head in relation
to the body, among other factors.
11-14
Hydrocephalus can be dened as CSF accumulation within
the ventricular cavities. It can have several causes such as
inammation, neoplasms, congenital malformations, and
consequent obstruction of CSF outow pathways in the
ventricles or subarachnoid space, leading, in most cases,
to increased intracranial pressure.
This increased intracranial pressure causes headache,
vomiting, lowered consciousness, seizures, coma, and even
death if left untreated. Differential diagnosis of the cause
of the pain can be difcult in patients with hydrocephalus.
However, patients with hydrocephalus treated either by a
shunt (ventriculoperitoneal shunt) or third ventriculostomy
may have headache of another etiology. The possibility
of shunt dysfunction has to be considered, but migraine
may be present in a patient with hydrocephalus,
especially if there is a strong family history of migraine.
An intriguing form of hydrocephalus when the patient
has a headache is the hydrocephalus associated with
a colloid cyst of the third ventricle.
15
Although the
association is rare, one of the authors (MMV) saw a few
patients with headache complain who went to his ofce.
The neuroimage investigation displayed a colloid cyst of
the third ventricle without hydrocephalus or associated
with a unilateral dilatation of the lateral ventricle, and the
fundus examination was normal. Is the colloid cyst of the
third ventricle an incidentaloma in these patients, and is
the headache of the primary type (e.g., migraine)?
Classically, third ventricle colloid cyst headache is
associated with the development of acute hydrocephalus
caused by a change in head position. In these cases,
neurosurgeons interpret the absence of hydrocephalus in
the image as a regression of hydrocephalus because the
cyst has moved, clearing the Monro's orice. They almost
always indicate an emergency surgery for fear of having
intermittent hydrocephalus.
One of the authors (MMV) recently became aware of a
case of a woman who had continuous pain in the right
frontal region, and neuroimaging showed the presence
of a colloid cyst in the third ventricle. This patient was
immediately operated on for the cyst. Days later, vesicles
appeared in the territory of the trigeminal branch. The
pain was due to ophthalmic herpes zoster.
Pseudotumor Cerebri
Idiopathic intracranial hypertension, also known as
pseudotumor cerebri
, is an idiopathic syndrome in which
increased intracranial pressure is observed without
hydrocephalus or associated expansive lesion. It most
often affects middle-aged obese women.
16-18
Other
associations have been described with the syndrome,
such as some use of specic drugs, endocrinopathies, and
nutritional disturbances.
18
The classic clinical presentation
is headache associated with visual loss, photophobia,
and tinnitus.
19-22
Some conditions associated with the development of
idiopathic intracranial hypertension, such as vitamin A
intake
23-25
, are described.
26
289
ASAA
Aragão MFVV, Araújo LC, Valença MM
Headache and neuroimaging findings in conditions of cerebrospinal fluid (CSF) circulation disorders: in hydrocephalus, pseudotumor cerebri, and CSF
hypotension syndrome
The most frequent radiological ndings are ectasia and
tortuosity of the cerebrospinal uid sheaths of the optic
nerves, papilledema, cerebrospinal uid insinuation
into the sellar cavity with compression of the pituitary
parenchyma (partially empty
sella
), enlargement of
Meckel's cavities, and stenosis of the lateral portions of
the transverse sinuses.
27-34
Cerebrospinal Fluid Hypotension
Cerebrospinal uid hypotension is characterized by
orthostatic headache associated with low CSF pressure,
usually resulting from CSF leakage due to lumbar punctures,
trauma, great physical exertion, severe dehydration, or
spontaneous tear of the dura mater.
35
Peak incidence is
among people between 30-40 years of age.
35
The patient characteristically presents with severe headache
(which may be orthostatic, pulsatile, with or without neck
stiffness), abducens nerve palsy, and visual disturbances.
35
The headache is self-limiting because the dura mater has
self-repairing properties, as observed in experiments with
human dura mater from adult cadavers.
36
Most cases
resolve spontaneously in one week.
35
Typical imaging ndings are
2, 37-38
:
• Smooth enhancement of the pachymeninge (dura mater);
• Engorgement of venous structures (dural venous sinuses,
cerebral veins, epidural venous plexuses);
• Pituitary swelling;
• Subdural hematomas and effusions;
• Herniation of structures (tonsils);
• Rectication of the anterior surface of the pons;
• Point of communication between the 3
rd
ventricle and the
aqueduct of Sylvius below the line between the anterior
clinoid process and the vein of Galen, and
• Reduction of the interpeduncular cistern of the pons.
Figure 1. A 29-year-old woman on the fourth postpartum day after cesarean delivery is evolving with headache and diplopia in the right eye. Non-con-
trast-enhanced sagittal T1 magnetic resonance imaging (A) shows that the cerebellar tonsils are at the level of the foramen magnum (arrows) therefore still
within normal limits (there is no previous MRI to compare), but that the opening of the cerebral aqueduct in the third ventricle is below the imaginary line
connecting the anterior clinoid to the vein of Galen, therefore lowered (short arrow). The axial T1-weighted images with post-contrast fat suppression (A
and B) show impregnation and thickening of the dura mater (arrows). There is also mild engorgement of the cerebral venous sinuses, best demonstrated
on T1 with post-contrast fat suppression (arrows, D), which is also identied on post-contrast magnetic resonance angiography (E and F), with no signs
of venous thrombosis. This case was courtesy of Dr. Jader Aretakis Cordeiro Filho, Recife, Brazil.
290
ASAA
Aragão MFVV, Araújo LC, Valença MM
Headache and neuroimaging findings in conditions of cerebrospinal fluid (CSF) circulation disorders: in hydrocephalus, pseudotumor cerebri, and CSF
hypotension syndrome
Comment
A neuroimaging investigation of the patient, particularly
those individuals with red ags such as postpartum
headache
39
, may reveal the cause of the headache. In
the example of postpartum headache, we have to think
of several possibilities.
40-42
The rst is to know whether it is
not just another migraine attack in patients who have been
migraineur for years, with a pattern of frequent attacks.
However, it is known that migraine attacks decrease or
even disappear during pregnancy
43
; they even remain
with low frequency during the period that the mother
breastfeeds her child.
44
Obviously, the characteristic of the
headache being precipitated when the woman gets out
of bed strongly suggests that it is a headache caused by
spinal anesthesia, if any. Post-dural puncture headaches
are prevalent after spinal anesthesia, mainly when the
anesthetist uses needles with a larger gauge. Needles
used to remove CSF for diagnosis are also usually of larger
gauge; therefore, the frequency of post-dural puncture
headaches is higher. Remember that individuals who have
already had post-dural puncture headaches have a greater
chance of having the same type of headache again.
45
Also,
patients with post-dural puncture headache may develop
subdural hematomas
46
, and neuroimaging evaluation may
show this type of complication of hypotension.
We also have to think about cerebral venous thrombosis in
the postpartum period.
47
Acknowledgement
We wish to thank Dr. Jader Aretakis Cordeiro Filho for
cooperating with the RMI shown in this article.
Contribution authors: MFVVA and LCA, wrote the article
and the selection of the gure; MMV, the nal edit of the
manuscript.
Conflict of interest: There was no conict of interest.
Maria de Fátima Viana Vasco Aragão
https://orcid.org/0000-0002-2341-1422
Luziany Carvalho Araújo
https://orcid.org/0000-0001-5072-8487
Marcelo Moraes Valença
https://orcid.org/0000-0003-0678-3782
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