(A) in the pathogenesis
(Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope) penetrating corneal transplant recipients in the pathogenesis of glaucoma is very complex, often multiple mechanisms common cause of intraocular pressure, a common mechanism:
Other corneal graft planting beds seams diffuse leakage can cause the iris forward, anterior chamber shallowing, angle closure. Operation preoperative ophthalmic surgical microscope (Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope), shallow anterior chamber, narrow angle keratoplasty surgery hypotony caused by choroidal detachment lens position can be moved forward and increased pupillary block. Corneal transplant (Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope) postoperative inflammatory response to the edge of the pupil and the lens, the intraocular lens or vitreous before limiting membrane adhesions or pupil vitreous hernia formation, is also a common pathological pupillary block. In addition, the inflammatory response can involve the ciliary body, ciliary body edema, convulsions and centered scleral forward displacement, rotation, the top pressure surrounding iris, iridocorneal angle Close. (Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope)After penetrating keratoplasty with corticosteroids to prevent immune rejection and the treatment of postoperative inflammation, corticosteroids may also lead to glaucoma in susceptible individuals.
. Iris adhesions anterior adhesions caused by the iridocorneal angle room water discharge significantly blocked, there are two kinds of the form. One is more common in the adhesion of the iris and corneal graft / implant bed together at shallow peripheral anterior chamber, but still exists. The main reason is due to edema of the corneal bed or graft thickening, or thickening of the iris inflammatory edema, or corneal graft / implant bed films of the aggregate non-performing, making both easier to contact adhesions; or suture plant iris The organization sewn together(Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope). Once the iris and cornea graft / implant bed together at the occurrence of adhesions, is likely to further expand to full weeks to form a ring adhesions, resulting in an acute increase in intraocular pressure. Another form of peripheral anterior synechia, suffering from eye before Operation often varying degrees of anterior synechia peripheral iris adhesions separated, and ophthalmic surgical microscope timely reconstruction of the anterior chamber (Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope) after Operation surgery, but or easier to form the peripheral anterior synechia, even heavier before adhesions. Peripheral anterior synechia can also be combined with cataract extraction and intraocular lens implantation. The possibility of multiple intraocular surgical trauma, anterior chamber hemorrhage and severe inflammatory exudation anterior synechia. (Eye surgical microscope,Eye Surgery microscope,Eye operating microscope,Eye Operation microscope)The penetrating keratoplasty use graft slightly larger than the planting beds to contribute to the restoration of the anterior chamber depth, to avoid too shallow peripheral anterior chamber due to postoperative anterior adhesions.
Trabecular meshwork collapse normal eye trabecular meshwork due to the presence of Descemet's former support and lens - after the support structure of the suspensory ligament of the complete system, therefore maintaining appropriate form and play normal drainage of aqueous humor. Olson and Kaufman proposed the concept of the trabecular meshwork collapse "that keratoplasty glaucoma (Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope) the occurrence of the trabecular meshwork collapse. The penetrating keratoplasty Descemet cut the trabecular meshwork to lose the support of the front. The study found that the the large grafts keratoplasty aqueous outflow decline more obvious, may be easier with weakened corneal Descemet relevant the former supporting role on the trabecular meshwork. If aphakia lens removal of the trabecular meshwork, losing the suspensory ligament tension, and weakened back support. So the trabecular meshwork lost the front and back support makes it easier to collapse, resulting in aqueous fluid coefficient decreased intraocular pressure. Clinical studies have also shown to cataract surgical methods (Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope) significantly affect penetrating keratoplasty combined with cataract removal surgery glaucoma incidence the joint capsule removal surgery the rate was 74%, while the joint capsule outside enucleation, compared with 45%.
(A) causes
Original glaucoma exists.
2 Long-term use of hormones.
Pupillary block lens vitreous blocking the pupil and inflammation induced pupillary membrane closure caused pupillary block.
4 angle-closure the extensive anterior adhesions (Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope) postoperative anterior chamber inflammation, peripheral anterior synechiae, causing angle closure.
(Eye surgical microscope,Eye Surgery microscope,Eye operating microscope,Eye Operation microscope)Surgical factors lax graft suture or suture ligation compact anterior chamber adverse or flattening due to corneal curvature, peripheral anterior chamber shallowing.
In addition to the above-mentioned reasons, especially after penetrating keratoplasty secondary glaucoma aphakia, with the following two mechanisms: 1 trabecular meshwork tissue collapse, because the Descemet's membrane cut to the front of the trabecular meshwork lost support, and the removal of the lens, hanging ligament tension disappear, so that the rear of the trabecular meshwork also lost support, (Eye surgical microscope,Eye Surgery microscope,Eye operating microscope,Eye Operation microscope,Eye (ophthalmic,ophthalmological,department of ophthalmology,specialty of ophthalmology) surgical (Surgery,operating,Operation) microscope)so that the collapse of the trabecular meshwork, aqueous discharge affected; ② conventional suture method may cause the iridocorneal angle oppressed, leading to surgery After intraocular pressure.
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