After thrombophlebitis of the affected sinus, it leads to cerebral venous circulation disorder, manifested as increased intracranial pressure. Its characteristics include cerebral venous congestion and tissue edema. The intracranial pressure is high, but the ventricles are dilated, which is different from the hydrocephalus caused by an increase in cerebrospinal fluid and ventricular dilation. Therefore, it is called otogenic hydrocephalus, also known as otogenic intracranial hypertension. Otogenic hydrocephalus has two types: one is true hydrocephalus caused by an increase in cerebrospinal fluid and ventricular dilation, and the other is intracranial hypertension due to cerebral venous circulation disorder following lateral sinus thrombophlebitis, known as pseudohydrocephalus. The latter is more common.

bubble_chart Etiology

1. True Hydrocephalus After intracranial infection complicated by meningitis and brain abscess, due to arachnoid membrane adhesion or aqueductal obstruction, the secretion of cerebrospinal fluid increases or absorption decreases, leading to an increase in cerebrospinal fluid and the formation of hydrocephalus.

2. Pseudotumor Cerebri Thrombophlebitis of the lateral sinus causes embolism of the dominant lateral sinus on the right side or both lateral sinuses simultaneously, leading to cerebral venous static blood edema, punctate cortical hemorrhages, cerebral tissue infarction and softening, and a sudden increase in intracranial pressure. However, the cerebrospinal fluid is not excessive, and the ventricles do not expand; instead, they may compress and shrink, hence it is called pseudotumor cerebri. The complication rate of lateral sinus thrombophlebitis is 2.5%.

Persistent headache, nausea, progressive weakening of vision, and even complete blindness, sometimes accompanied by paralysis of the extraocular muscles.

bubble_chart Diagnosis

Recently suffered from intracranial complications such as lateral sinus thrombophlebitis, high lumbar puncture pressure, occasional fundus edema, no space-occupying signs, CT and MRI can rule out intracranial space-occupying sexually transmitted disease changes. Superior sagittal sinus venography shows thrombosis in the lateral sinus.

bubble_chart Treatment Measures

Dehydration therapy is administered, such as oral glycerol or intravenous infusion of 20% mannitol 250ml, 2-3 times daily. Lumbar puncture is performed daily or every other day to release 30-50ml of cerebrospinal fluid. If there is progressive fundus edema and optic nerve atrophy, a subtemporal decompression or lateral ventricle drainage should be promptly performed to save vision. For true hydrocephalus, a lateral ventricle to external jugular vein anastomosis or a spinal canal to thoracic cavity anastomosis should be performed.