Microincision Cataract Surgery
Microincision Cataract Surgery
Absence of the main incision facilitates planning of the two side small incisions. It is important to put incisions on the axis of the corneal astigmatism. Two incisions put on the axis of 90° spread symmetrical force of the corneal biomechanics. SIA by MICS is generally neutral. Proper incision planning and use of limbal relaxing incisions may lead to refractive neutrality of surgery and improve corneal image quality.
Two side incisions may facilitate continuous curvilinear capsulorhexis (CCC). It is quite challenging to do incision of 1.5 mm while performing capsulorhexis. MICS capsulorhexis forceps help in tearing the capsule with ease. In case of complicated capsule tear, the angle and side of the forceps can be changed to enhance CCC.
Great advantage of the bimanuality can be seen in the nucleus fragmentation. Hydrochopper with the hook help with mass breakdown and maintains distance of the posterior capsule from the phaco tip. Aspiration of the masses is much easier than in the standard technique.
Two equal incisions give the opportunity to choose the better incision to implant the lens. While selecting the incisions for IOL implantation, the rule of the dominant incision to diminish the corneal astigmatism is followed.
Diminishing of the incision is minimization of the surgery trauma. Diminishing incision size should minimize surgical trauma. Smaller incisions should diminish the wound recovery time. Probably decrease of incision should minimize deformation of the cornea and inflammation of the eye. Idea of incision minimization provoked progress in cataract surgery. Surgery with incision under the 1.8 mm needs to be performed in non-standard coaxial way. Bimanuality provokes to open two symmetrical clear corneal incisions. Incision size symmetry allows us to freely operate from each side. Access to each part of the anterior chamber is smooth. Performing the regular capsulorhexis is easy from right and left sides. To perform MICS incision you need calibrated knife. Calibration is required in two planes. First is the incision shape. Internal incision should be shorter than external one. Difference should be about 0.2 mm. Trapezoidal shape of the incision allow us to perform surgery without corneal damage. Trapezoidal shape facilitates horizontal movements of the tools or phaco tip. Internal incision seals the wound and wider external incision facilitates movements. Corneal traumatism was eliminated by this way. There is one more advantage of the micro incision. Incision lower than 1.8 mm allows to close wound without any complication. This dimension of the incision is the self-sealing incision. They are closed after the surgery spontaneously or with small amount of hydratation. This is particularly important for the post-SIA and aberrations. The wound integrity and the self-sealing properties of the MICS and coaxial incisions are currently one of the most important agents in the endophthalmitis prophylaxis. On the other side, Can et al. described higher percentage of Descemet membrane detachment in the MICS group. Elkady et al. did not show any difference between MICS and coaxial groups in incision integrity after surgery using optical coherence tomography.
Irreversible changes may affect the cornea. Every incision of the cornea evokes the change of corneal curvature. Kaufmann et al. confirms that MICS incision offers astigmatic neutrality in the cataract surgery, it supports the idea of MICS as the refractive procedure. The authors of this study proved that MICS and microphaco provided similarly good incision quality and optically neutral incisions. The MICS incision respected corneal prolateness more, with less corneal edema in the short term and less induced corneal aberrations in the long term. In the other studies, Tong et al. supported the perfect MICS optical result. Cataract surgery-related changes in corneal wavefront aberrations were dependent on incision size. The MICS technique had advantages over the small-incision cataract surgery (SICS) technique in minimizing the destructive effect of the large incision size on the optical quality of the cornea.
Several studies report significant reduction in the hysteresis CH and CRF after cataract surgery postoperative period. In the study by Alió et al., incision smaller than 1.5 mm provides more stable CH than coaxial phacoemulsification incision. MICS provides more stable cornea than deformation and applied force overtime. One more advantage of the small incision is IFIS reduction. Moore and Goggin describe MICS as the stable technique which can suppress floppy iris prolapse during surgery (Table 1).
Bi-MICS Technique
Bimanuality in MICS
Absence of the main incision facilitates planning of the two side small incisions. It is important to put incisions on the axis of the corneal astigmatism. Two incisions put on the axis of 90° spread symmetrical force of the corneal biomechanics. SIA by MICS is generally neutral. Proper incision planning and use of limbal relaxing incisions may lead to refractive neutrality of surgery and improve corneal image quality.
Two side incisions may facilitate continuous curvilinear capsulorhexis (CCC). It is quite challenging to do incision of 1.5 mm while performing capsulorhexis. MICS capsulorhexis forceps help in tearing the capsule with ease. In case of complicated capsule tear, the angle and side of the forceps can be changed to enhance CCC.
Great advantage of the bimanuality can be seen in the nucleus fragmentation. Hydrochopper with the hook help with mass breakdown and maintains distance of the posterior capsule from the phaco tip. Aspiration of the masses is much easier than in the standard technique.
Two equal incisions give the opportunity to choose the better incision to implant the lens. While selecting the incisions for IOL implantation, the rule of the dominant incision to diminish the corneal astigmatism is followed.
Incision
Diminishing of the incision is minimization of the surgery trauma. Diminishing incision size should minimize surgical trauma. Smaller incisions should diminish the wound recovery time. Probably decrease of incision should minimize deformation of the cornea and inflammation of the eye. Idea of incision minimization provoked progress in cataract surgery. Surgery with incision under the 1.8 mm needs to be performed in non-standard coaxial way. Bimanuality provokes to open two symmetrical clear corneal incisions. Incision size symmetry allows us to freely operate from each side. Access to each part of the anterior chamber is smooth. Performing the regular capsulorhexis is easy from right and left sides. To perform MICS incision you need calibrated knife. Calibration is required in two planes. First is the incision shape. Internal incision should be shorter than external one. Difference should be about 0.2 mm. Trapezoidal shape of the incision allow us to perform surgery without corneal damage. Trapezoidal shape facilitates horizontal movements of the tools or phaco tip. Internal incision seals the wound and wider external incision facilitates movements. Corneal traumatism was eliminated by this way. There is one more advantage of the micro incision. Incision lower than 1.8 mm allows to close wound without any complication. This dimension of the incision is the self-sealing incision. They are closed after the surgery spontaneously or with small amount of hydratation. This is particularly important for the post-SIA and aberrations. The wound integrity and the self-sealing properties of the MICS and coaxial incisions are currently one of the most important agents in the endophthalmitis prophylaxis. On the other side, Can et al. described higher percentage of Descemet membrane detachment in the MICS group. Elkady et al. did not show any difference between MICS and coaxial groups in incision integrity after surgery using optical coherence tomography.
Irreversible changes may affect the cornea. Every incision of the cornea evokes the change of corneal curvature. Kaufmann et al. confirms that MICS incision offers astigmatic neutrality in the cataract surgery, it supports the idea of MICS as the refractive procedure. The authors of this study proved that MICS and microphaco provided similarly good incision quality and optically neutral incisions. The MICS incision respected corneal prolateness more, with less corneal edema in the short term and less induced corneal aberrations in the long term. In the other studies, Tong et al. supported the perfect MICS optical result. Cataract surgery-related changes in corneal wavefront aberrations were dependent on incision size. The MICS technique had advantages over the small-incision cataract surgery (SICS) technique in minimizing the destructive effect of the large incision size on the optical quality of the cornea.
Several studies report significant reduction in the hysteresis CH and CRF after cataract surgery postoperative period. In the study by Alió et al., incision smaller than 1.5 mm provides more stable CH than coaxial phacoemulsification incision. MICS provides more stable cornea than deformation and applied force overtime. One more advantage of the small incision is IFIS reduction. Moore and Goggin describe MICS as the stable technique which can suppress floppy iris prolapse during surgery (Table 1).
