Vorhersage des postoperativen visuellen Outcome mittels real-time ICG-Angiographie nach Resektion von perichiasmatischen Meningeomen

The most common clinical presentation of patients with perichiasmatic meningiomas is visual disturbance, and surgical resection is the main mode of treatment to preserve vision. The only available, however not reproducible, intraoperative measurements to evaluate the visual function is the iVEP (intraoperative visual evokes potential). This study aims to provide a reproducible safe alternative for iVEP to predict the visual outcomes of perichiasmatic meningiomas.

Five patients with perichiasmatic meningiomas and 5 patients with other perichiasmatic pathologies were included and studied retrospectively. Each patient received a complete imaging study, ophthalmological examination and iVEP and a standardized ICG-angiography. ICG-angiography was done pre-and postresection applying flow 800 software, (Kinevo, Carl Zeiss Co). The intervals between the first appearance of ICG in the internal carotid artery (ICA) and pial circulation of the ON (optic nerve) to full saturation of both were measured at each pre-and postresection situation.

5 Patients (1M,4F) and 5 controls (4M,1F) are included. The mean age was 60.2±15.35 and 56.4±10.31 years old for cases and controls respectively. Visual disturbance was reported in 5 cases and 4 controls preoperatively. The main pathologies included 5 perichiasmatic meningiomas, 1 hypophysis adenoma, 2 craniopharyngiomas and one hypophysis metastasis. Visual improvement was reported in 4 cases, 1 unclear and 4 controls. Comparing the tumor volume of meningioma to other pathologies does not show any significant difference (p>0.05). Peak time differences of ICA-ON before tumor resection was 2.44±2.81ms for meningiomas and 3.03±2.81ms for controls (p>0.05). After tumor resection, the peak time was 2.14±1.73ms for meningioma patients and 3.66±2.79ms for control patients respectively (p>0.05). The peak-time improvement of ICA-ON between the two groups showed no significant difference. Prolonged iVEP latency was observed in both groups, more at the affected side of chiasma.

Applying ICG-angiography to evaluate the ophthalmic postoperative outcome seems to be a safe reproduceable method comparing to the iVEP. Compared to other perichiasmatic pathologies, meningiomas has not shown a significant difference in term of visual outcomes. Further studies need to evaluate the significance of ICG-angiography as a tool of intraoperative monitoring of the optic nerve.