Key-words:
Basilar skull fractures - cerebrospinal fluid meningitis - leak - rhinorrhea
Introduction
Cerebrospinal fluid (CSF) rhinorrhea is not an unusual complication of head trauma
which occur in 2% of patients with head trauma.[[1]] It usually occurs through dural tear and associated anterior skull base fracture.
Rarely fracture of temporal bone occurs and fluid leak through middle fossa defect
through eustachian tube to the nasopharynx results in paradoxical CSF rhinorrhea.[[2]]
Case Report
A 53-year-old woman referred to our department with the complaint of clear watery
discharge from the right nostril. She gave a history of head trauma due to car accident
6 years ago that underwent surgery for the evacuation of right temporal intraparenchymal
hematoma.
She suffered from intermittent rhinorrhea starting 5 years after trauma which had
lasted for 1 year and had been continuous for the previous 3 months. She had two bouts
of meningitis after rhinorrhea that was treated conservatively in a different hospital.
She had no anosmia, and other neurological examinations were normal.
Routine biochemical and hematological investigations were within the normal range.
The image findings of axial brain and coronal sinus computed tomography (CT) scans
were evidence of previous right temporal craniotomy and adjacent parenchymal changes.
CT cisternography, after intrathecal injection of 20cc Visipaque (VISIPAQUE Injection
270 mgI/ml, 20 ml, GE Healthcare, Norway), did not show bony defect on the anterior
cranial fossa or detectable contrast leakage into the paranasal sinuses and nasal
cavity (not shown).
Beside the mentioned findings, coronal T2-weighted magnetic resonance images depicted
the high signal intensity area in favor of encephalomalacia in the left inferior temporal
region associated with fluid signal in the left tympanic cavity and mastoid air cells
[[Figure 1]]. It was the only clue to reassess the axial brain CT scan which revealed partial
opacity of left mastoid air cells [[Figure 2]], and further evaluation with coronal images of the petrous bone which depicted
large bony defect of the left tegmen tympani, tegmen mastoideum associated with opacity
in the middle ear cavity, and lateral displacement of the ossicles [[Figure 3]].
Figure 1: Coronal T2.weighted image depicts encephalomalacic changes in both temporal lobes.
Increased signal is also present in the left middle ear which was the clue to the
presence of cerebrospinal fluid leak
Figure 2: Axial computed tomography scan of the brain depicts partial opacity of the left mastoid
air cells
Figure 3: Coronal reformat of petrous temporal computed tomography scan depicts bony defect
in left tegmen tympani associated with opacity in the middle ear and lateral displacement
of ossicles
The patient suspected to have paradoxical CSF rhinorrhea through eustachian tube from
the defect of left temporal bone.
For further documentation, she underwent endoscopic transnasal examination after intrathecal
injection of fluorescein dyes, which showed leakage of fluorescein, from left eustachian
tube to the nasopharynx.
The patient underwent surgical repair of leakage through transmastoid approach.
The patient is placed in a lateral decubitus position, and a curve line incision behind
the mastoid was performed. A wide mastoidectomy is performed and repair of the floor
of middle fossa with fascia and autograft bone, and eustachian tube closure was done
extradural.
Discussion
A total of 17 cases of delayed posttraumatic CSF rhinorrhea including the present
case are described in [[Table 1]].
Table 1: Cases of delay post traumatic cerebrospinal fluid leak
CSF leaks most commonly result from nonsurgical trauma (80%–90% of cases), 16% from
surgical procedures and the remaining 4% are nontraumatic.[[3]],[[6]],[[14]],[[17]],[[18]],[[19]],[[20]]
It complicates 12%–30% of all basilar skull fractures.[[1]]
Moreover, it is associated with about a 10% risk of developing meningitis per year.[[1]],[[12]],[[15]],[[17]],[[18]],[[21]],[[22]],[[23]] Traumatic CSF rhinorrhea is classified as immediate (within 48 h) or delayed.
More than 50% of traumatic CSF rhinorrhea occurred within the first 48 h and almost
all present within the first 3 months,[[19]] delayed CSF leak beyond 3 months seen in the 5% of patients, whereas delay beyond
a year is very rare.[[24]] However, prolonged delay of up to 44 years has been reported.[[14]]
The mechanisms of delayed CSF leak are the resolution of edema, absorption of blood
clot, contracture of scar, and necrosis of soft tissues or bone.[[1]]
Usually, fluid leaking through dural tearing and associated fracture of anterior cranial
fossa involving cribriform plate and posterior wall of the frontal sinus and sphenoid
sinus.
Rarely, paradoxical CSF rhinorrhea could be occurred.[[2]]
Paradoxical rhinorrhea is rhinorrhea from the naris contralateral to the site of CSF
leakage which can occur with displaced fractures of the midline structures, the crista
galli and vomer, or in the setting of mucocele formation obstructing the ipsilateral
naris.
Paradoxical rhinorrhea also could be seen after temporal bone fractures when the fluid
leak from tearing of the temporal dura and travels down to the nasopharynx through
the eustachian tube.[[22]]
Paradoxical CSF rhinorrhea usually manages conservatively with good success in the
acute setting, but in the cases of recurrent meningitis or delay CSF rhinorrhea, it
seems that surgical repair associated with the best outcome.[[23]]
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms.
In the form the patient(s) has/have given his/her/their consent for his/her/their
images and other clinical information to be reported in the journal. The patients
understand that their names and initials will not be published and due efforts will
be made to conceal their identity, but anonymity cannot be guaranteed.
