Computerized tomography showed there was skull defect at floor of the anterior cranial fossa at
cribiform plate of the ethmoid on left side lateral to nasal septum.
Drainage also occurs through the arachnoid villi in the sub-arachnoid space, flowing via blood and lymph into the lymphatics of the cranial nerves, the spinal nerves, inner ear and the
cribiform plate of the ethmoid bone (forms the roof of the nasal cavity) (1).
Although
cribiform plate fractures may not always be visible radiologically, the presence of a pneumocephalus indicates that the cranial cavity has been breached.
The diagnosis was a misplaced nasogastric tube forced through the
cribiform plate. Regardless of the cause of the patient's unconsciousness, a new problem now exists that complicates her prognosis.
But if their conduit through the
cribiform plate closes, smell loss will be irreversible.
(28) The portal of entry for humans appears to be the nasal mucosa with subsequent invasion of the olfactory nerve plexus and rapid travel ( (24) hours) of the amoebae up the olfactory nerves, through the
cribiform plate and into olfactory bulb and spread to other areas of the CNS.
Blocking cerebrospinal fluid absorption through the
cribiform plate increases resting intracranial pressure.
Excystation occurs quickly, and the trophozoites penetrate the nervous plexus, cross the
cribiform plate and enter the brain.
The infection occurs when water containing the amoeba is forced up into the nasal passages, attaches to the olfactory mucosa, and migrates across the
cribiform plate into the brain via the olfactory bulbs.
Postradiation examination revealed a 6-mm mass at the posterior aspect of the
cribiform plate. MRI found two suspected metastases in the dura of the left temporal lobe (figure 2).
Stigmata of old TBI on an MRI also include areas of encephalomalacia and gliosis, particularly in areas prone to coup-contrecoup forces, such as the frontal lobe (anterior as well as inferior margin along the
cribiform plate), anterior temporal lobe, and the occipital pole.