Turkish Neurosurgery
Understanding of Dry Eye in Subarachnoid Hemorrhage: An Experimental Study on The Role of Facial Nerve Ischemia
Osman Tanriverdi1, Mehmet Dumlu Aydin2, Mehmet Resid Onen3, Ilhan Yilmaz4, Mustafa Kilic4, Nazan Aydin5, Aslihan Duman6, Sevilay Ozmen7
1University of Health Sciences, Bakırköy Prof Dr Mazhar Osman Training and Research Hospital for Neurology, Neurosurgery and Psychiatry, Neurosurgery, İstanbul,
2Atatürk University Medical Faculty, Neurosurgery, Erzurum,
3University of Health Sciences, Ümraniye Training and Research Hospital, Neurosurgery, İstanbul,
4University of Health Sciences, Şişli Hamidiye Etfal Training and Research Hospital, Neurosurgery, İstanbul,
5University of Health Sciences, Bakırköy Prof Dr Mazhar Osman Training and Research Hospital for Neurology, Neurosurgery and Psychiatry, Psychiatry, İstanbul,
6Giresun University Medical Faculty, Pathology, Giresun,
7Atatürk University Medical Faculty, Pathology, Erzurum,
DOI: 10.5137/1019-5149.JTN.22979-18.3

Aim:Subarachnoid hemorrhage can cause “dry eye” as it denervates the parasympathetic ganglia and reduces tear production. We used a rabbit model of subarachnoid hemorrhage to understand possible mechanisms underlying lacrimal gland degeneration when facial nerve root ischemia induces pterygopalatine ganglion injury and subsequent dry eye.Material and Methods:Rabbits were divided into four groups: control, sham, moderate subarachnoid hemorrhage, and severe subarachnoid hemorrhage. Autologous blood recovered from the auricular artery was injected into the cisterna magna to induce subarachnoid hemorrhage in the two subarachnoid hemorrhage groups; animals were then monitored for dry eye development over 21 days before removal of their facial nerve roots, pterygopalatine ganglia, and lacrimal glands for immunohistochemical analyses. Neuronal viability in the pterygopalatine ganglia was measured; lacrimal gland vesicles were counted by stereological methods.Results:The mean tear-filled vesicle number and lacrimal gland volumes significantly decreased with an increase in facial nerve root injury severity and damaged neuron numbers in the pterygopalatine ganglion. Increase in injury severity most significantly decreased the tear-filled vesicle numbers in the pterygopalatine ganglion. Conclusion:Subarachnoid hemorrhage degenerates facial nerve parasympathetic branches entering the pterygopalatine ganglion, and neuronal density in this ganglion may be correlated with tear secretion. Our data suggest that pterygopalatine ganglion degeneration following subarachnoid hemorrhage induces dry eye.

Corresponding author : Mehmet Dumlu Aydin