Background and purpose: Isolated lateral sinus thrombosis was long considered a complication of middle ear disease. Little attention has been recently paid to this variety of thrombosis. We therefore reviewed all cases of isolated lateral sinus thrombosis prospectively collected in our center (1997 to 2006).
Methods: Among 195 patients with cerebral venous thrombosis (CVT), we identified 157 patients with lateral sinus thrombosis, including 62 patients with isolated lateral sinus thrombosis. Clinical, etiologic, and prognostic features were compared with those of other 133 CVT cases.
Result: Sixty-two patients (32%) had isolated lateral sinus thrombosis. Headaches were present in 95% of patients. The main clinical presentation was isolated headache in 28 patients (45%), whereas 15 (24%) had isolated intracranial hypertension. Nineteen patients (31%) had at least one focal sign (deficit and/or focal seizure). Dysphasia was the most common one (8 patients). Compared with the other 133 CVT cases, presentation with isolated headaches was the most frequent one (P<0.001). Parenchymal lesions were found in 19 cases and were less frequent than in other CVT cases (P=0.007). Numerous causes or predisposing factors were identified without a difference in repartition with other patients with CVT, particularly for local or infectious causes. Treatment consisted of anticoagulation in all patients. Clinical outcome was good with complete recovery in 57 patients (92%). One patient died after the occurrence of massive pulmonary emboli despite adequate anticoagulation. Three patients had sequelae (no difference with the other CVT).
Conclusions: Isolated lateral sinus thrombosis is a frequent variety of CVT, accounting for one third of all CVT. It presents in more than two thirds of cases with headache as the only symptom either isolated or less frequently associated with papilledema. This stresses the need for CVT workup in a patient with a recent unexplained headache.