Role of CT Perfusion in Predicting Poor Outcome After Subarachnoid Hemorrhage

Study Overview
=================
Brief Summary
-----------------
Prospective evaluation of patients with subarachnoid hemorrhage (SAH) will be done by computed tomography angiography (CTA) and perfusion imaging (CTP) for any correlation between degree of vasospasm and perfusion deficit as well as evaluating the ability of CTP to predict delayed cerebral ischemia.

Detailed Description
-----------------
Cerebral vasospasm is a serious complication of subarachnoid haemorrhage . In the first 2 weeks of SAH, angiographic vasospasm is seen up to 40-70% of patients and causes ischemic deficits in 15-36% of patients. The best clinical indicator of significantly reduced brain perfusion (cerebral blood flow (CBF)<20 ml per 100 g/min) is the presence of new neurologic deficits. However, clinical symptoms may be vague and mimic other conditions in patients with SAH. CT Perfusion can be used in the evaluation of patients with possible vasospasm after subarachnoid hemorrhage (SAH). It can thus be used to assess cerebral ischemia and infarction as a result of vasospasm after SAH. The presence of cerebral vasospasm identified with transcranial Doppler, digital subtraction angiography, or CT angiography (CTA) is frequently used to confirm DCI. Presence of vasospasm, however, does not prove the presence of ischemia and absence of vasospasm does not rule out. Better diagnostic tests in the acute stage of deterioration, possibly caused by DCI, are therefore needed. In patients with SAH, CTP has recently been shown to be promising for detection of early ischemia.

Official Title
-----------------
Role of Computed Tomography Perfusion in Detection of Patients at Risk for Delayed Cerebral Ischemia After Subarachnoid Hemorrhage

Conditions
-----------------
Subarachnoid Hemorrhage, Cerebral Vasospasm, Delayed Cerebral Ischemia

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: All patients presented with subarachnoid haemorrhage Exclusion Criteria: Patients with abnormal renal functions with creatinine ≥ 2 mg/dl/ Patients with hypersensitivity to contrast media. Contraindication to radiation as pregnancy.
Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with poor outcome<br>Follow up of patients is done for 21 days by combined clinical and radiological examination. Poor clinical outcome is associated with vasospasm leading to permanent neurological deficit, stroke or death. | |
| Patients without poor outcome<br>Patients who do not develop delayed cerebral ischemia or stroke, confirmed by combined clinical and radiological examination. | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cerebral blood flow (CBF) on Admission | Cerebral blood flow (CBF) on Admission in units of ml/100 gram brain tissue/ minute. The measurements will be compared with the outcome of the patient (namely monitoring delayed cerebral ischemia in SAH patients) to test if early CT perfusion could predict the poor outcome in SAH patients. | 3 days from the attack | 
| Cerebral blood volume (CBV) on Admission | Cerebral blood volume (CBF) on Admission in units of ml/100 gram brain tissue. | 3 days from the attack | 
| Mean transit time (MTT) on Admission | Mean transit time (MTT) on Admission in units of seconds. | 3 days from the attack | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of vasospasm to perfusion abnormality using Comparing between CT angiography and CT perfusion in patients with subarachnoid hemorrhage | Evaluating results of CT angiography and CT perfusion in patients for Correlating vasospasm and perfusion abnormality. Results will be dichotomous; positive and negative, then tested by cross tabulation. | 4-14 days from the attack | 
| Hunt and Hess scale | Hunt and Hess clinical scale was performed for every patient. Grades are as the following: Grade 1: Asymptomatic or mild headache Grade 2: Cranial nerve palsy or moderate to severe headache/nuchal rigidity Grade 3: Mild focal deficit, lethargy, or confusion Grade 4: Stupor and/or hemiparesis Grade 5: Deep coma, decerebrate posturing, moribund appearance | 3 days from the attack | 
| Fisher scale | Fisher scale quantifies the amount of SAH as the following: None evident Less than 1 mm thick More than 1 mm thick Diffuse or none with intraventricular hemorrhage or parenchymal extension | 3 days from the attack | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
CT perfusion, Subarachnoid hemorrhage, Vasospasm, Delayed cerebral ischemia