Empty delta sign

Empty Delta Sign

The empty delta sign is a radiological sign observed in computed tomography (CT) scans of the brain, indicative of a cerebral venous sinus thrombosis (CVST). This sign is crucial for the diagnosis of CVST, a condition where a blood clot forms in the dural venous sinuses, which drain blood from the brain. The empty delta sign represents the presence of a clot within the sinus, with the enhancement of the dural sinus walls around the non-enhancing thrombus, giving the appearance of an empty triangle or delta on contrast-enhanced CT scans.

Etiology

Cerebral venous sinus thrombosis can result from various conditions, including infection, dehydration, pregnancy, use of oral contraceptives, and coagulopathy. These factors can increase the risk of blood clot formation within the venous sinuses.

Pathophysiology

The pathophysiology of CVST involves the formation of a thrombus within the cerebral venous system, leading to impaired venous drainage. This impairment can cause increased intracranial pressure, leading to symptoms such as headache, vomiting, seizures, and in severe cases, encephalopathy. The empty delta sign is a direct imaging manifestation of the thrombus, surrounded by contrast-enhanced blood flow.

Clinical Presentation

Patients with CVST may present with a wide range of symptoms, including but not limited to, headache, blurred vision, seizures, and neurological deficits. The presentation can vary significantly, making the diagnosis challenging without imaging.

Diagnosis

The diagnosis of CVST primarily relies on imaging techniques, with magnetic resonance imaging (MRI) and magnetic resonance venography (MRV) being the gold standards. However, the empty delta sign is specifically associated with contrast-enhanced CT scans, which can quickly suggest the diagnosis in the appropriate clinical context.

Treatment

Treatment of CVST focuses on anticoagulation to prevent clot propagation, with heparin or warfarin being commonly used. In severe cases, thrombolytic therapy or surgical intervention may be necessary. Early diagnosis and treatment are crucial to improve outcomes and reduce the risk of complications.

Prognosis

The prognosis of CVST varies, with most patients recovering fully with appropriate treatment. However, the condition can be life-threatening if not promptly diagnosed and treated, with potential complications including intracranial hemorrhage, seizures, and long-term neurological deficits.

See Also

• Cerebral venous sinus thrombosis
• Computed tomography
• Magnetic resonance imaging