Results
The scores of PALT and Benton BVRT significantly declined one week following surgery in both Nitroglycerine and Phentolamine groups. There was no statistically significant difference between Nitroglycerine and Phentolamine groups in the postoperative decline in either PALT or BVRT (P-value = 0.342, 0.662 respectively). The values of P300 latency showed a significant delay one week following surgery in both Nitroglycerine and Phentolamine groups (P-value ≤ 0.001, 0.001), but in Nitroglycerine group, the delay is significantly higher than in Phentolamine group (P-value = 0.003). The values of P300 amplitude significantly decreased one week following surgery in both Nitroglycerine and Phentolamine groups (P-value ≤ 0.001, 0.001), but there was no statistically significant difference between Nitroglycerine and Phentolamine groups (P-value = 0.099).