What Causes Cerebrospinal Fluid Rhinorrhoea?

Cerebrospinal fluid nasal leakage is the discharge of cerebrospinal fluid through the skull base (anterior, middle, or posterior fossa) or other parts of bone defects and ruptures, through the nasal cavity, and finally out of the body. The main manifestation is the intermittent or continuous outflow of clear, watery liquid from the nasal cavity. Due to early mixing with blood, the liquid may be light red.

Basic Information

English name: cerebrospinal rhinorrhea
Visiting department: ENT, neurosurgery

Common locations: Anterior, middle or posterior fossa
Common causes: Traumatic and iatrogenic, spontaneous, neoplastic and congenital
Common symptoms: Intermittent or continuous nasal discharge of clear, watery fluid

Cerebrospinal fluid rhinorrhea

Causes of cerebrospinal fluid rhinorrhea

The causes of cerebrospinal fluid rhinorrhea can be divided into traumatic and non-traumatic, of which traumatic can be divided into traumatic and iatrogenic; non-traumatic can be divided into spontaneous, tumorous and congenital.

Cerebrospinal fluid rhinorrhea classification

There are many classification methods for cerebrospinal fluid rhinorrhea, according to anatomy, etiology, and intracranial pressure. As the etiology affects the treatment and prognosis of cerebrospinal fluid rhinorrhea, classification according to the etiology is most clinically valuable. Cerebrospinal fluid rhinorrhea is classified into traumatic and non-traumatic according to the etiology, and the latter is divided into spontaneous, tumorous and congenital. Cerebrospinal fluid rhinorrhea caused by trauma is the most common clinically.

Traumatic cerebrospinal fluid rhinorrhea

(1) Traumatic cerebrospinal fluid nasal leakage Traumatic cerebrospinal fluid nasal leakage is most commonly caused by car accident injuries.

(2) Iatrogenic cerebrospinal fluid rhinorrhea Cranionasal communication tumors, skull base tumors, and inflammation. Skull base lesions must be treated during surgery, which may cause iatrogenic cerebrospinal fluid rhinorrhea.

2. Non-traumatic cerebrospinal fluid rhinorrhea

(1) Tumor-derived cerebrospinal fluid rhinorrhea Sinus and skull base tumors can directly or indirectly cause cerebrospinal fluid rhinorrhea. These tumors may be primary central nervous system tumors that have spread to the nasal cavity, or nasal cavity and sinus tumors that have spread to the skull. Tumor-based treatments, such as surgery, radiotherapy, or chemotherapy, can cause ischemia around the leak and invasion of the skull base, making it difficult to repair. Tumors can also block cerebrospinal fluid circulation and cause increased intracranial pressure, which indirectly leads to nasal leakage of cerebrospinal fluid.

(2) Congenital cerebrospinal fluid nasal leakage Congenital cerebrospinal fluid nasal leakage mostly occurs near the sieve plate and the top of the ethmoid sinus. Common causes are malformations of the skull base and bone defects in the skull base. Intracranial pressure in patients with congenital cerebrospinal fluid rhinorrhea is often in the normal range, and may also be accompanied by increased intracranial pressure.

(3) Spontaneous cerebrospinal fluid rhinorrhea The cause of spontaneous cerebrospinal fluid rhinorrhea is unknown, so it is also known as primary or idiopathic cerebrospinal fluid rhinorrhea. The most common leak is the sieve plate, followed by sphenoidal scoliosis, which may be due to ischemic atrophy of the sieve plate or saddle floor, and is then filled with cerebrospinal fluid-filled arachnoid sacs. The cerebrospinal fluid pulsates the skull base and invades local bone formation The defect eventually leads to a cerebrospinal fluid nasal leak.

Clinical manifestations of cerebrospinal fluid rhinorrhea

The main manifestation is the intermittent or continuous outflow of clear, watery liquid from the nasal cavity. Due to early mixing with blood, the liquid may be light red. More common on one side. Features of increased flow under conditions such as lowered head pressure and compression of the jugular vein suggest that cerebrospinal fluid nasal leakage may be possible. Traumatic cerebrospinal fluid nasal leakage can also have bloody fluid flowing out of the nostrils, the center of the trace is red and the surroundings are clear, or the colorless liquid flowing out of the nostrils does not look like diarrhea after drying. Cerebrospinal fluid nasal leakage should be considered. It usually occurs after the injury, and late-onset patients can appear within days, weeks, or even years.

Cerebrospinal fluid rhinorrhea examination

Endoscopy

Can be used routinely, positioning leaks accurately. When the cerebrospinal fluid continues to flow out, the endoscope may directly find the cerebrospinal fluid nasal leak. When the cerebrospinal fluid leakage is small or intermittent, the intrathecal injection of fluorescein can be used in order to find the leak. Compression of bilateral internal jugular veins during the examination caused an increase in cranial pressure, which was conducive to observing a leak.

2.Detection of glucose oxidase

This technique is a traditional diagnostic method. Because tears and nasal mucus contain sugar, sugar is not qualitatively reliable, and a quantitative sugar test is feasible. Detect the concentration of glucose in the nasal fluid and compare it with the concentration of glucose in the serum. If the ratio is 0.50 to 0.67, the fluid is likely to be cerebrospinal fluid, excluding other factors that can cause changes in the concentration of glucose in the cerebrospinal fluid and serum. If the glucose concentration in the leaked solution is greater than 1.7 mmol, the diagnosis can also be confirmed.

3.-2 transferrin detection

This technique is very effective for the diagnosis of cerebrospinal fluid rhinorrhea. Because -2 transferrin is only found in cerebrospinal fluid and lymphatic fluid outside the inner ear, it cannot be detected in blood, nasal cavity, and external ear canal secretions. Take 0.2mL specimens and use immunofixation electrophoresis technology to detect, its sensitivity and specificity are high.

4.-2 tracer protein detection

In recent years, -2 tracer protein has only been found in cerebrospinal fluid and extraauricular lymphatic fluid, and its sensitivity and specificity are higher.

5.CT and CT brain pool angiography

High-resolution CT, the layer thickness can be as thin as 1mm, and the detection rate of small lesions is significantly improved. Three-dimensional CT imaging technology was used to reconstruct the skull base, and the fracture condition was displayed more intuitively to clarify the leakage site. CT cisternography has high specificity and can directly show the shape, size, location and number of cerebrospinal fluid nasal leaks. However, it is not possible to fully understand the leakage situation, and the bone structure is not clear. Combined with CT, it is more perfect.

6. Intrathecal and local fluorescein method

Intrathecal injection of fluorescein combined with endoscopy is a commonly used method for intraoperative cerebrospinal fluid leakage positioning, which is of great help in the diagnosis of cases with less fluid leakage or intermittent cerebrospinal fluid nasal leakage. The larger the visual field exposure during surgery, the more accurate the diagnosis, but the smaller the exposure to the skull base bone defect, the precise positioning of the leak is limited. Local intranasal fluorescein method can be used for preoperative diagnosis, intraoperative localization, and detection of postoperative recurrence. It is a non-invasive examination, simple, safe, and highly sensitive.

7.MRI and MRI water imaging

The most prone position of cerebrospinal fluid leakage, that is, the prone position, is used to select the axial, sagittal, or coronal T1 weighted images, T2 weighted images, and fast spin echo T2 weighted images of fat suppression. Parts. The widely used MRI water imaging technology is accurate in locating leaks.

Cerebrospinal fluid nasal leak diagnosis

The diagnosis of cerebrospinal fluid rhinorrhea mainly depends on symptoms, signs and auxiliary examination. Symptoms: Clear fluid is continuously or intermittently discharged from one or both nostrils. Symptoms worsen when you lean to one side, lower your head, or compress the jugular vein; or there is less water leakage, but the pillow is wet in the morning. There are also only repeated intracranial bacterial infections, rhinorrhea is not obvious. Generally, the incidence is mainly caused by traumatic brain injury and surgery. A few patients have only a history of slight traumatic brain injury or nasal leakage after sneezing.

Differential diagnosis of cerebrospinal fluid rhinorrhea

Allergic rhinitis

Allergic rhinitis may show symptoms of clear water-like snot and should be distinguished from this disease. However, allergic rhinitis is accompanied by continuous sneezing, itching, and nasal congestion, and has a clear allergen. Biochemical examination of secretions can be identified.

2. Sinus submucosal cyst

Subsinus submucosal cysts are most common above the maxillary sinus. When the cyst is ruptured, a yellow cooling fluid can flow out, unilaterally, and should be identified. Feasible imaging examination and biochemical examination.

Cerebrospinal fluid rhinorrhea complications

Intracranial infection and low intracranial pressure.

Cerebrospinal fluid rhinorrhea treatment

Non-surgical treatment

In general, patients with cerebrospinal fluid rhinorrhea should be treated conservatively, especially the conservative treatment of traumatic cerebrospinal fluid rhinorrhea should also be used throughout the treatment of cerebrospinal fluid rhinorrhea. The course of treatment can be determined according to the condition, usually about 2 to 4 weeks, and the period should be closely observed.

(1) Patients with bed rest Cerebrospinal fluid nasal leakage should be absolutely bedridden to avoid aggravating cerebrospinal fluid nasal leakage. Generally, a semi-sitting position with a head height of 200 to 30 ° is used, lying on the affected side, and the brain tissue can sink to the leak to promote natural healing.

(2) Ensure that the nasal cavity is clean, keep the nasal cavity clean and the cerebrospinal fluid flowing out, and wash the leakage immediately to avoid local blockage, which leads to cerebrospinal fluid, reverse flow and local bacterial growth.

(3) To prevent the increase of intracranial pressure, you can use mannitol and furosemide to reduce intracranial pressure, prevent colds, keep the stool open, and give laxative drugs to avoid constipation. It is not advisable to hold your breath, blow your nose and cough, etc. action.

(4) Application of antibiotics The use of antibiotics depends on the condition to determine the time and cycle of medication. Because the leak is connected to the extracranial, patients with cerebrospinal fluid nasal leakage may potentially have meningitis. Generally, when cerebrospinal fluid nasal leakage exceeds 24 hours, there is a possibility of meningitis, especially concealed cerebrospinal fluid nasal leakage. Recurrence of meningitis. Once meningitis occurs, adequate antibiotics should be given. Gram-negative bacteria are common in intracranial infections caused by cerebrospinal fluid rhinorrhea, so cephalosporin antibiotics are the main clinical.

(5) Lumbar great cistern drainage for traumatic cerebrospinal fluid nasal leakage, lumbar great cistern drainage is feasible for 5 to 7 days. The patient was lying on his back. The lateral lying position was selected with L3 ~ 4 or L4 ~ 5 clearance puncture. The tube was inserted into the subarachnoid space. The end was connected with a sterile drainage bag. The height of the drainage bag was adjusted to control the drainage. Catheter placement in the lumbar cistern can reduce intracranial pressure and reduce cerebrospinal fluid outflow, which is conducive to the spontaneous healing of nasal leakage of cerebrospinal fluid.

2. Surgical treatment

(1) Endoscopic intranasal approach to cerebrospinal fluid rhinorrhea repair Wigand successfully used fibrin glue to repair cerebrospinal fluid rhinorrhea under nasal endoscope for the first time in 1981. Now this technology is widely developed, showing its great advantages, reported Has a success rate of more than 90% and is commonly used by otolaryngologists. Nasal endoscopic repair is the first choice for the treatment of ethmoidal sinus and sphenoid sinus cerebrospinal fluid nasal leakage. The difficulty is to determine the location of the leak during the operation. Carefully look for the source of the cerebrospinal fluid nasal leak with the aid of nasal endoscope, and then remove the For granulation tissue and necrotic tissue, fully flush the operation area, use muscle fascia and other repair materials to fully cover the leak and oppress.

(2) Transcranial cerebrospinal fluid leakage repair surgery This surgery is a traditional surgical treatment method commonly used by neurosurgeons. Its indications: those with multiple fractures and extensive craniocerebral injury up to the craniotomy indication, craniotomy for hematoma fractures and leaks; high intracranial pressure cerebrospinal fluid rhinorrhea that can lead to death of cerebral hernia; those who fail or relapse after other methods of repair Intracranial abscess formation; severe skull base deformity; intracranial and extracranial communication tumors, single nostril approach under nasal endoscopy and microscopy showing difficulty, when the skull base defect or large leak can be preferred. According to the different parts of the fracture and the location of the cerebrospinal fluid nasal leak, the subfrontal approach and the pterygoid approach can be selected. According to the intraoperative situation, the epidural approach and the intradural approach and the combined approach can be used. The advantage is that the leak can be repaired under direct vision, and other intracranial lesions can be processed at the same time; the disadvantage is that it is not easy to find the leak during the operation, the trauma is longer, the operation and hospitalization time is longer, and the smell is more affected. The craniotomy under microscope is now widely used, which obviously makes up for the lack of craniotomy in the past.

(3) The extranasal approach under the microscope often uses the extranasal frontal sinus, ethmoid sinus, and sphenoid sinus surgery. The extranasal approach to the cerebrospinal fluid rhinorrhea of the frontal sinus has the advantage of large surgical field and can be combined with the intranasal method; The disadvantage is that the facial appearance is affected. When repairing the ethmoid or sphenoid sinus, the middle turbinate is often damaged, and nasal function is affected. Due to the development of endoscopic techniques, the extranasal approach has gradually been replaced by the intranasal approach.

(4) The single intranasal approach under the microscope uses a neurosurgery microscope. The single nostril approach is adopted. This technique is suitable for the leaks located on the sieve plate, the posterior ethmoid roof and the sphenoid sinus top wall. The location of the leak is relatively clear. Its advantages are that it is convenient to operate with both hands, the operation field is clearly enlarged, the trauma is small, and the complications are small. The disadvantages are straight line observation, limited and narrow surgical field of vision, and the frontal sinus and sphenoid sinus side walls cannot be observed.

3. Postoperative treatment

(1) Bed rest: patients with cerebrospinal fluid nasal leakage should stay in bed absolutely to avoid aggravating cerebrospinal fluid nasal leakage. Generally, the head is 20 to 30 ° in a semi-sitting position, lying on the affected side, and the brain tissue can sink to the leak to promote healing.

(2) Ensure clean nasal cavity: Avoid local bacterial growth.

(3) Prevention of increased intracranial pressure: mannitol and furosemide can be used to reduce intracranial pressure, prevent colds, keep the stool open, and give laxative drugs to avoid constipation. It is not advisable to hold your breath, blow your nose and cough, etc. Pressing action.

(4) Apply antibiotics after surgery.

References

1. Zhuang Huiwen, Wen Weiping, Li Jian, etc. Diagnosis and treatment of traumatic delayed cerebrospinal fluid rhinorrhea: Chinese Journal of Otorhinolaryngology Head and Neck Surgery, 2010: 45 (3): 190-192.

2. SieskiewiczA, LysonT, RogowskiM, etal. Endosopicmanagementofcerebrospinalfluidrhinorrhea: OtolaryngolPol, 2009: 63 (4): 343-347.