An ophthalmological device for surgical treatment of a cornea of an eye, the ophthalmological device comprising: a patient interface , the patient interface comprising an applanation body and one or more suction elements configured to fix the applanation body to the cornea for applanating the cornea in an applanation zone where the applanation body is in contact with the exterior surface of the cornea ; a laser source configured to generate a pulsed laser beam (B); a focusing optical module configured to make the pulsed laser beam (B) converge onto a focus (F) in the cornea ; a scanner system configured to move the focus (F) to target locations in the cornea ; and an electronic circuit configured to control the scanner system to move the focus (F) to cut inside the cornea a lenticule (L), the lenticule (L) having a posterior lenticule surface (Lp) and an anterior lenticule surface (La), characterized in that the electronic circuit is further configured to control the scanner system to move the focus (F) to cut in the cornea a venting channel (Ch, Ch1, Ch2), the venting channel (Ch, Ch1, Ch2) comprising an opening incision (Co, Co1, Co2) in a peripheral area of an exterior surface of the cornea , outside a perimeter (q) of the lenticule (L) from a top view perspective onto the cornea and outside the applanation zone, and the venting channel (Ch, Ch1, Ch2) connecting fluidically at least one of the posterior lenticule surface (Lp) or the anterior lenticule surface (La) to the opening incision (Co, Co1, Co2), to enable venting of gas produced by cutting the lenticule (L) inside the cornea through the opening incision (Co, Co1, Co2) to the exterior of the cornea outside the applanation zone. a patient interface , the patient interface comprising an applanation body and one or more suction elements configured to fix the applanation body to the cornea for applanating the cornea in an applanation zone where the applanation body is in contact with the exterior surface of the cornea ; a laser source configured to generate a pulsed laser beam (B); a focusing optical module configured to make the pulsed laser beam (B) converge onto a focus (F) in the cornea ; a scanner system configured to move the focus (F) to target locations in the cornea ; and an electronic circuit configured to control the scanner system to move the focus (F) to cut inside the cornea a lenticule (L), the lenticule (L) having a posterior lenticule surface (Lp) and an anterior lenticule surface (La), characterized in that the electronic circuit is further configured to control the scanner system to move the focus (F) to cut in the cornea a venting channel (Ch, Ch1, Ch2), the venting channel (Ch, Ch1, Ch2) comprising an opening incision (Co, Co1, Co2) in a peripheral area of an exterior surface of the cornea , outside a perimeter (q) of the lenticule (L) from a top view perspective onto the cornea and outside the applanation zone, and the venting channel (Ch, Ch1, Ch2) connecting fluidically at least one of the posterior lenticule surface (Lp) or the anterior lenticule surface (La) to the opening incision (Co, Co1, Co2), to enable venting of gas produced by cutting the lenticule (L) inside the cornea through the opening incision (Co, Co1, Co2) to the exterior of the cornea outside the applanation zone. <EOS>