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Examples of "endogenous" or direct and "endogenous" or indirect endothelial trauma are presented. Corneal contusion, McCannel suture, YAG laser iridectomy, congenital luxation of the lens, and chronic over wearing of contact lenses all cause traumatic changes. The etiology and effects of these changes are discussed. Specular microscopy of the corneal endothelium permits good clinical control of both the trauma and wound healing.
Of 132 patients who had undergone Nd-YAG laser iridotomy, 70 were randomly selected for follow-up examinations. Nd-YAG laser iridotomies were subsequently performed on 124 eyes (of these 70 patients), 12 for acute angle-closure glaucoma, 19 fellow eyes of those which had angle-closure glaucoma, 70 for chronic angle-closure glaucoma, and 23 eyes with increasingly narrow chamber angle under miotic therapy. The follow-up period ranged from 1 to 25 months (median = 9 months). Eighty-seven percent of the iridotomies remained visibly open. Of 12 acute glaucomas, 10 were successfully treated, whereas only 2 required a basal iridectomy. In the large group of 106 eyes with a "narrow angle condition," a significant pressure reduction from 20.9 +/- 5.8 to 16.7 +/- 3.4 mm Hg and a significant enlargement of the chamber angle resulted. Since fistulizing procedures involve a risk of malignant glaucoma, Nd-YAG laser iridotomy, which this investigation showed to be risk-free, is the initial procedure of choice in narrow-angle conditions, especially subacute and chronic angle-closure glaucoma, in order to alleviate the angle-closure component in such angle-closure situations, to diagnose its contribution to peak IOP, and to facilitate argon laser trabeculoplasty when needed.
A case of sympathetic uveitis which developed after several operations to reduce intraocular pressure is reported. Initially there was a thrombosis of the central vein; secondary glaucoma developed after laser coagulation and iridectomy; six operations followed. Some months later the diagnosis of sympathetic uveitis was established. The pathogenesis of sympathetic uveitis in this case is discussed.
A number of aspects of glaucoma surgery are discussed. Complete drainage of the aqueous via the subconjunctival space results in underperfusion of the trabecular meshwork, leading to significant impairment of the trabecular function. In certain cases, therefore, we prefer trabeculotomy, even though its pressure-lowering effect is inferior to that of fistulizing surgery: trabeculotomy preserves the unaffected trabecular meshwork. Laser trabeculoplasty has the advantage of increasing the outflow facility. In angle-closure glaucoma, iridectomy is performed as an initial procedure in every case in order to eliminate pupillary block. The transcorneal approach ensures watertight wound closure and preserves the conjunctiva for fistulizing surgery if necessary. Glaucoma surgery can usually be performed in lid akinesia and subconjunctival infiltration. This alternative helps to avoid retrobulbar injection when the optic nerve is already severely damaged by glaucoma.
In 78 eyes treated by different fistulizing procedures (57 by goniotrepanation or trabeculectomy, 13 by Elliot trepanation and 8 by iridencleisis) extracapsular cataract extraction with implantation of posterior chamber lenses was performed. A sector iridectomy had to be performed in about 40% of the eyes because of difficulties in dilatation of the pupils and posterior synechiae. Postoperatively the IOP was regulated in 83% of all eyes without additional topical medication; a second fistulizing procedure was only necessary in one eye. Complications such as keratopathies, posterior capsule fibrosis, and dislocations of the posterior chamber lenses were not found to be more frequent compared with nonglaucomatous eyes treated by extracapsular cataract extraction with implantation of posterior chamber lenses.
The author describes a miniature bipolar diathermy unit which can be used for several microsurgical purposes. It was developed from a standard endodiathermy instrument which has been in use for pars plana vitrectomy since 1973. It features bipolar forceps which can be used for welding conjunctival flaps and macrohemostasis in strabismus, orbital and lid surgery; bipolar electrodes with and without infusion, for extraocular hemostasis and intraocular microhemostasis in the anterior and posterior segments; bipolar electrodes with infusion for special purposes (still at the experimental stage), for capsulotomy of the anterior lens capsule for extracapsular cataract extraction, section of intraocular strands and membranes and sector iridectomy for tumors or rubeosis of the iris.
A-mode echography was performed on 745 patients of the University of Jordan, Amman, to exclude intraocular tumor in cases of retinal detachment, to localize foreign bodies in the eye and orbit, to evaluate eyes with opaque refracting media, and to discover the causes of exophthalmus. The equipment provided reliable information about the different ocular and orbital disorders. Abnormal echograms were found in about 48% of the patients who had opaque refractive media, hyphema, or occlusion of the pupil. Therefore, when the retina is intact, an improvement in visual acuity can be expected in only 52% of patients after perforating keratoplasty, visual iridectomy or cataract operation. The other 48% may need further procedures such as vitrectomy or retinal detachment surgery. Echography, therefore, serves the ophthalmologist as a guide in choosing the surgical procedure and predicting the probable outcome of surgery.
Description of various affections of the iris which may be treated with argon-laser. The problem of the laser iridectomy in the treatment of glaucoma is illustrated by a histologic study of the evolution of the lesions up to four months after coagulation of rabbit's iris.
From 1964 to 1980, 255 patients suffering from choroidal melanoma underwent a primary eye-preserving procedure. Of these, 205 were irradiated with 106Ru/106Rh beta-ray applicators (dose: 80-100 Gy at the summit of the tumor within 14 days). In 132 cases (64.4%) this treatment was successfully within a follow-up period of 5.4 years: 60 patients (45.5%) developed a flat scar, 34 (25.8%) retained a visual acuity of 1.5 to 0.5. Thirty-six eyes had to be enucleated after radiotherapy. Thirty-seven patients died, 21 of them from metastases. The survival rate, 85.1% after five years and 71.9% after ten years, is significantly higher than that of patients whose eyes were enucleated as a primary procedure. Fifty patients suffering from melanoma of the anterior uveal tract were treated with the following surgical procedures: iridocyclectomy in 42 cases, iridectomy in three cases and choroidectomy also in three cases. Twenty patients retained a visual acuity of 1.5 to 0.8 during the average follow-up period of 7.5 years. In 11 patients the eye had to be enucleated later. Four patients died from metastases. The survival rate of this group with local tumor excision was 96% during the follow-up period.
After covered fistulizing operations for primary glaucoma without complications the anterior chamber is deeper than it was prior to surgery. This means that the contact between the posterior surface of the iris and the lens may be very important in the pathogenesis of all primiary glaucomas, especially in acute primary glaucoma: an acute iridolenticular block can develop. Severe blocking mechanisms of the posterior surface of the iris sometimes appear after fistulizing glaucoma operations and after cataract extractions (with and without implantation of a pseudophakos) if there is no postoperative dilatation of th pupil. Peripheral iridectomies alone cannot prevent the anterior chamber from becoming shallower or flattened, possibly with the development of malignant glaucoma.
We describe a 3-month-old patient with a primary epithelial cyst of the iris stroma. Although these cysts account for 16% of all childhood iris cysts, these cysts are uncommon with only a small number of reported cases.(1-6) Because our patient's cyst had amblyogenic potential, we proceeded with surgical treatment. The cyst was aspirated, but it recurred within 7 weeks. Sector iridectomy with excision of the cyst was performed, again with recurrence and subsequent glaucoma and cataract. These cysts present difficult management issues concerning the choice of initial surgical treatment and subsequent complications.
Angle closure glaucoma remains a major challenge for ophthalmologists. The three main challenges in the treatment of angle closure glaucoma are, firstly, to achieve rapid reduction of intraocular pressure in acute angle closure glaucoma, secondly, to prevent progression to chronic angle closure glaucoma, and thirdly, to manage established chronic angle closure glaucoma. Incisional surgery for angle closure glaucoma is typically required when laser surgery and/or medical therapy fail to control the intraocular pressure or control progressive synechial closure. The role for surgical iridectomy and emergency trabeculectomy in the modern management of acute angle closure glaucoma is diminishing. Trabeculectomy, goniosynechialysis, cyclodestructive procedures, and glaucoma implant are effective surgical options for chronic angle closure glaucoma, but none of them have been shown to be more effective than the others with proper comparative clinical trials. Trabeculectomy and goniosynechialysis are often combined with cataract extraction, which appears to offer additional pressure-control benefits to patients with chronic angle closure glaucoma.
Glaucoma is best detected by examination of the optic disk, since intraocular pressure is not always elevated in patients with the condition. A large, vertically oval cup within the optic disk is strong evidence for glaucoma. Open-angle glaucoma, the most common form of the disorder, often is not detected until the disease is advanced. It can usually be treated successfully with topical medications, but systemic absorption of these can result in serious side effects. If medical treatment fails, laser therapy or filtering surgery may be helpful. Acute angle-closure glaucoma has a sudden onset marked by alarming elevations in intraocular pressure. It is treated immediately with topical pilocarpine and systemic osmotic agents, and an iridectomy should be performed as soon as possible. Congenital glaucoma can be cured with goniotomy.
The effects of benzydamine eye drops on the ocular reaction to different irritating stimuli in rabbits are reported. Benzydamine at the concentration of 0.1% reduces inflammatory tissue changes induced by AgNO3 burning of the cornea and inhibits the blood-aqueous barrier breakdown due to peripheral iridectomy or laser irradiation of the iris. Benzydamine reduces the aqueous PGE2 concentration to a similar extent as a 0.5% commercially available eye drop formulation of piroxicam. This result is in contrast with previous in vitro results demonstrating that benzydamine is devoid of any effects on PG synthesis. The possibility that PGE2 reduction is an indirect effect due to other biochemical activities of benzydamine is discussed. In the normal eye benzydamine manifests a local anaesthetic effect which is not accompanied by irritative changes in the anterior segment of the eye, changes in the intraocular pressure or pupillary size. It is suggested that in the clinical use of benzydamine eye drops the local anaesthetic activity may contribute to reducing both the neurogenic component of ocular inflammation and acute pain following injuries to the eye.
Peptides related to melanotropin (alphaMSH) and corticotropin (ACTH), collectively termed melanocortins, are known to improve the postlesion repair of injured peripheral nerves. In addition, melanocortins exert trophic effects on the outgrowth of neurites from central nervous system neurons in vitro. Here we report, for the first time, the stimulation by alpha-MSH of spinal neurite outgrowth in vivo after injury. In the in vivo model, spinal cord trauma was produced at lower thoracic spinal levels of adult rats. Under a surgical microscope a laminectomy was performed exposing the dorsum of the spinal cord. Then the dura was cut longitudinally and the dorsal columns were identified. Iridectomy scissors were used to transect the dorsal half of the spinal cord bilaterally, thereby completely lesioning the main corticospinal tract component. Then the lesion gap was immediately filled with a solid collagen matrix. Ingrowth of fibers was quantified using an advanced image analyser using a video image of sections transmitted by a camera. In the control situation virtually no ingrowth of sprouting injured fibers into the collagen implant in the lesion gap was seen. However, when the collagen matrix contained 10(-8) M alpha-MSH, a profound and significant stimulation of fiber ingrowth into the implant was observed (alpha-MSH, 21.5 +/- 2.9%; control, 1.4 +/- 0.6% p < 0.01). A small percentage of these ingrowing fibers was CGRP-immunoreactive (17.0 +/- 4%), whereas no serotonergic ingrowth was observed. Furthermore, we found that local application of alpha-MSH directs a substantial amount of lesioned anterogradely labelled corticospinal tract axons to regrow into the collagen implant (alpha-MSH, 15.2 +/- 5.2%; control, 0.5 +/- 0.3%, p < 0.01). The observed fiber ingrowth is not accompanied by an invasion of astroglial or reactive microglial cells into the implant. In conclusion, inclusion of alpha-MSH in the collagen implant stimulates the regrowth of injured axons in the adult rat spinal cord.
A cut was made on the middorsal skin of newborn mice of strains C57BL/10J, C57BL/10J-A/A, and C3H/He using fine iridectomy scissors. In the epidermis within 1 mm of the wound edge in C57BL/10J and C57BL/10J-A/A, the melanocyte population positive to the dopa reaction as well as the melanoblast-melanocyte population positive to the combined dopa-premelanin reaction increased dramatically until the 3rd day, then gradually decreased. In contrast, the melanocyte population of C3H/He did not increase after wounding, despite that the melanoblast-melanocyte population increased. Pigment-producing melanocytes in mitosis were frequently found in C57BL/10J and C57BL/10J-A/A, but not in C3H/He. The F1, F2, and backcross matings were performed to get some information about the genetic basis of the difference between C57BL/10J and C3H/He. In the F1 generation the offspring from reciprocal crosses exhibited intermediate values in both populations on the 3rd day after wounding. The F2 generation included the C3H/He type, F1 type, and C57BL/10J type in a ratio of 1:2:1 in both populations. Moreover, both reciprocal backcrosses gave 1:1 ratios of parent type to F1 type in both populations. These results indicate that the proliferative activity of mouse epidermal melanocytes during the healing of skin wounds are controlled by semidominant genes.
PURPOSE: Defects in the iris are associated with clinically significant optical anomalies, such as glare and peripheral light scatter; however, current artificial-iris technology remains inadequate. The purpose of this study was to explore the practicality of a lamellar intrastromal tattoo technique as a treatment modality to correct optical and cosmetic defects resulting from simulated iris abnormalities in eye-bank eyes. METHODS: Simulated iris defects (abnormally large pupil, sector iridectomy, iridodialysis, and aniridia) were produced in a series of eye-bank eyes. Depending on the simulated iris defect, one or two lamellar channel(s) were created at 50% depth of the cornea via a peripheral incision (1.8 mm) with specialized proprietary instruments (KeraVision, Inc., Fremont, CA, U.S.A.). Commercially available tattoo pigment was inserted through the lamellar channel(s) and blended into the defective region of the iris. RESULTS: The tattoo treatment was relatively simple to perform. Tattoo pigment was inserted uniformly through the small incision, and adequate color blending to match the recipient iris was achieved. The intrastromal tattoo effectively obscured light. CONCLUSION: The lamellar intrastromal tattoo technique appeared to be efficacious for treating different types of iris defects in eye-bank eyes. Further investigation of this technique in nonsighted patient eyes is warranted.
PURPOSE: To evaluate the use of ultrasound biomicroscopy (UBM) in examining the status of anterior-segment structures in eyes with corneal opacification. METHODS: Evaluation with UBM was performed between 1 and 2 weeks before surgery in 21 patients (21 eyes) with corneal opacities who were scheduled for penetrating keratoplasty. UBM findings were correlated with the findings noted during penetrating keratoplasty. The efficacy of UBM evaluation was calculated in terms of positive and negative predictive values (PPVs and NPVs) for the presence or absence of each finding. RESULTS: Seventeen eyes had either aphakic or pseudophakic bullous keratopathy (ABK or PBK). UBM findings of anterior synechiae, peripheral anterior synechiae, posterior synechiae, peripheral and sector iridectomies positively correlated with those observed during surgery in five (55.6%) of nine locations, 19 (73.1%) of 26 locations, 12 (80%) of 15 locations, eight (88.9%) of nine locations) and six (85.7%) of seven locations, respectively. The NPVs for these findings were 100%, six (54.5%) of 11 locations), 10 (71.4%) of 14 locations, 12 (100%) of 12 locations, and 14 (100%) of 14 locations, respectively. Correlation for findings pertaining to the posterior capsule (PC) were presence of PC/PC remnants [PPV, 13 (92.9%) of 14 locations; NPV, two (66.7%) of three locations], presence of central PC tears [PPV, two (66.7%) of three locations], intactness of PC [PPV, six (85.7%) of seven locations], and PC thickening [PPV, 13 (81.25%) of 16 locations; NPV, four (100%) of four locations]. For vitreous in the anterior chamber, the PPV was eight (100%) of eight locations, and NPV was 12 (92.3%) of 13 locations. Pseudophakos-related information in eyes with PBK showed a PPV of 100% for presence, centration, and anatomic location (seven of seven, four of four, and seven of seven locations, respectively). CONCLUSION: In eyes with corneal opacity, UBM determines the status of various anterior-segment structures. It is thus a useful adjunct in the preoperative planning and prognostication of patients requiring penetrating keratoplasty.