Innovative intraocular lens design to manage surgical aphakia in an eye with a filtering bleb.

An innovative intraocular lens (IOL), the CM-T Flex IOL, was used to correct surgical aphakia without disturbing a functioning filtering bleb. A 66-year-old man presented with aphakia in the left eye. Cataract extraction and trabeculectomy was performed in the left eye 2 years previously elsewhere. Corrected distance visual acuity (CDVA) in the left eye was 6/18, and, on examination, it showed a filtering bleb that encroached on the limbus and superior cornea. The cornea was clear with a deep anterior chamber. Retinal examination was normal. Disc cupping was noted with a cup-to-disc ratio of 0.8. Refractive correction was performed by implanting the CM-T Flex IOL. This IOL has a unique design that eliminates the need for maneuvering the IOL haptics extraocularly. It entails a simple grasp, exteriorize, and release technique that anchors the IOL firmly to the scleral bed. At 6 months, CDVA in the left eye was 6/9 with a stable, centered IOL.

Acupuncture Alleviates Levodopa-Induced Dyskinesia via Melanin-Concentrating Hormone in Pitx3-Deficient aphakia and 6-Hydroxydopamine-Lesioned Mice.

Although L-3,4-dihydroxyphenylalanine (L-DOPA) is currently the most effective medication for treating Parkinson's disease (PD) motor symptoms, its prolonged administration causes several adverse effects, including dyskinesia. To identify the mechanisms underlying the effects of acupuncture on L-DOPA-induced dyskinesia (LID), antidyskinetic effects of acupuncture were investigated in two mouse models of PD. Acupuncture stimulation at GB34 alleviated abnormal involuntary movements (AIMs) in Pitx3-deficient aphakia mice (ak/ak) following L-DOPA administration and these effects were reproduced in 6-hydroxydopamine (6-OHDA)-lesioned mice with LID. A transcriptome analysis of the hypothalamus revealed pro-melanin-concentrating hormone (Pmch) gene was highly expressed in acupuncture-treated mouse from ak/ak model of LID as well as 6-OHDA model of LID. Acupuncture combined with the administration of MCH receptor antagonist did not have any beneficial effects on dyskinesia in L-DOPA-injected ak/ak mice, but the intranasal administration of MCH attenuated LID to the same degree as acupuncture in both ak/ak and 6-OHDA mice with LID. A gene expression profile with a hierarchical clustering analysis of the dyskinesia-induced ak/ak mouse brain revealed an association between the mechanisms underlying acupuncture and MCH. Additionally, altered striatal responses to L-DOPA injection were observed after prolonged acupuncture and MCH treatments, which suggests that these treatment modalities influenced the compensatory mechanisms of LID. In summary, present study demonstrated that acupuncture decreased LID via hypothalamic MCH using L-DOPA-administered ak/ak and 6-OHDA mouse models and that MCH administration resulted in novel antidyskinetic effects in these models. Thus, acupuncture and MCH might be valuable therapeutic candidates for PD patients suffering from LID.

Central corneal thickness and glaucoma in aphakic and pseudophakic children.

BACKGROUND: The risk of glaucoma among aphakic children is as high as 32%, based primarily on intraocular pressure (IOP) measurements. Although IOP may be falsely elevated by increased central corneal thickness, central corneal thickness (CCT) values have not been reported in this population. METHODS: Patients from the practices of 2 pediatric ophthalmologists and 2 glaucoma specialists had measurements of CCT, IOP, and optic nerve cupping, with visual field analysis when possible. Normal fellow eyes of unilateral aphakes and pseudophakes were included as controls. RESULTS: In 36 aphakic and 6 pseudophakic eyes CCT averaged 660 microns compared with 576 microns for phakic fellow eyes (P < 0.0001). Glaucoma, defined by IOP at least 35 mm Hg or by IOP at least 22 mm Hg associated with optic nerve changes, occurred in 21% of 28 aphakic patients but in no pseudophakic patient. CONCLUSIONS: CCT in aphakic/pseudophakic children is substantially increased compared with control patients. These values may be important in interpreting IOP measurements in these children.

Comparison of Clinical Results between Sulcus Insertion and Transscleral Fixation of Intraocular Lenses

To compare clinical results between sulcus insertion of intraocular lens(IOL)(Group I) and transscleral fixation of IOL(Group II), visual acuity, spherical equivalent, astigmatism, corneal thickness and intraocular pressure were evaluated, retrospectively. This study was performed on 37patients(43 eyes), who could have been followed up more than 12 months from September 1994 to August 1997. Six mm scleral incision at 12 o'clock position and sulcus insertion of IOL were used with 2 interrupted sutures in cases of aphakia either with some remained anterior capsule or with continuous curvilinear capsulorhexis(Group I, 12 eyes). The same incision and suture method with transscleral fixation of IOL were used in case of aphakia with little remained anterior capsule(Group II, 31 eyes). In Group II, 10-0 polyprolene sutures were buried beneath the scleral flaps at both three and nine o'clock meridians following transscleral fixation of IOL. Uncorrected visual acuity(UCVA) was improved in both Group I and Group II, except for 4 cases of Group II. Lack of improvement of UCVA did not seem to be related to the operative methods. The changes of UCVA, astigmatism, corneal thickness and intraocular pressure were not statistically significant between the two groups. In conclusion, transscleral fixation of posterior chamber-intraocular lens turned out to be safe and effective in certain cases of insecure zonule or posterior capsule, although its surgical procedure is more complicated than that of posterior chamber-intraocular lens implantation into the sulcus without fixation.

Retinal Detachment Following Scleral Fixation of Posterior Chamber Intraocular Lens

The authors reviewed retrospectively retinal detachment(RD)s following posterior chamber intraocular lens(PC-IOL) implantation by transscleral suture fixation. One hundred twenty-two transscleral fixations of PC-IOL were performed from January, 1990 to December, 1992. The follow-up periods for this series ranged from 12 to 42 months. Six retinal detachments developed in this series. and the incidence of RD was 4.9%. There was no statistical difference between the primary operation group(unplanned posterior capsule rupture during extracapsular cataract extraction, lens dislocation/subluxation) and the secondary operation group(already aphakia after previous cataract surgery). The predisposing factors to RD were myopic eye(p=0.03), postoperative vitreous hemorrhage(p=0.001). In cases with RD, the locations of transscleral fixation sutures almost coincided with the meridians of the retinal breaks. The contributing factors to increased incidence of RD were thought to be vitreous loss during operations, vitreous traction by suturing needle or haptics of IOL, proliferative change by vitreous hemorrhage.

The role of 5-fluorouracil in complicated glaucomas.

The long-term efficacy of trabeculectomy in controlling intraocular pressure (IOP) has been found unsatisfactory in various complicated and refractory glaucomas. The most common cause for failure is excessive scarring at the filtering site. Several wound modulating agents which reduce scarring have been tested. In this study, 5-Fluorouracil (5-FU), a halogenated pyrimidine analogue and a potent anti-mitotic agent, was applied for seven days after trabeculectomy in eighteen complicated and unsuccessful filtering glaucomas, at a daily dosage of 5 mg in the form of 0.5 ml subconjunctival injections. The common postoperative complications encountered were corneal epithelial erosion (38%), wound leakage (16%), subconjunctival haemorrhage (32%) and hyphaema (10%), all during the first 7 to 10 days. Monitoring at regular intervals up to six months showed adequate control of IOP (less than 22mm Hg.) in 88% of the cases. Cases of aphakic glaucoma and neovascular glaucoma showed poor response. Use of 5-FU as an adjuvant to filtering surgery in various complicated glaucomas improves the long-term results.

Filtering Surgery in Aphakia and Pseudophakia

Aphakic or pseudophakic glau-oma is known to be at high risk for failure after filtration surgery. The authors retrospectively investigated the results of trabeculectomy in 14 eyes of 14 patients with glaucoma, seven aphakic and seven pseudophakic eyes, which were followed from six months to three years with an average ot 16.5 months. A conventional trabeculectomy without using antifibrotic agents was performed in all the eyes. The site of conjunctival incision was prepared on the virgin area of the conjunctiva; 8 superonasal, 4 inferonasal and 2 inferotemporal approaches. An average postoperative intraocular pressure reduction was 13.4 mmHg. The number of medications decreased in 11 eyes. A spontaneously developed functioning bleb was found in seven eyes. In other four eyes, the filtering bleb was formed with an aid of massage or needling. The remallllllg three eyes did not show a functioning bleb. Postoperative complications included hyphema in 3 eyes, overfiltration in 2 eyes, choroidal detachment in 1 eye, corneal edema in 1 eye and endophthalmitis in 1 eye.

Correction of Aphakia

An aphakic eye is usually strongly hypermetropic; in the absence of the lens, parallel rays of light are brought to a focus 31mm behind the cornea, while the average antero-posterior diameter of the eye is only 23 to 24mm. The dioptric system must therefore be supplemented by a strong converging lens, usually, if the eye were originally emmetropic, of about +10 D. The aphakic eye suffers from several disadvantages. Astigmatism, due to operative interference with the cornea, is frequently present. The accommodation is abolished, and consequently the patient should theoretically be provided with a pair of glasses for every distance at which he desires to see clearly. In practice it is usually sufficient to provide a glasses for distant vision, one for reading distance, with in addition, in many cases, one for an intermediate position. A further considerable disadvantage is the limitation of the visual field, for the spectacles do not move with the eyes, and the prismatic effects produced by their periphery are great. The patient must therefor learn to move his head rather than his eyes, especially on looking, downwards, so that he always uses the central portion of his glasses. The optical conditions are completely changed. The image in a lens less eye, corrected by spectacles, is about 33% larger than when the lens is present. The visual acuity is therefore theoretically worse than that is indicated by the usual clinical tests. This enlargement introduces a false spatial orientation of familiar objects, which, being of unusual size, are judged to be nearer than they actually are. Partly owing to the total lack of accommodation, and partly, and in greater measure, owing to the increased size of the retinal image, an aphakic eye can rarely be used in association with a normal one. Aphakia thus becomes an extreme and accentuated example of anisometropia. A unilateral cataract is removed, it is rarely wise to attempt to the correction of the aphakic eye by glasses. In addition, two optical defects inseparable from the use of strong lenses exist - the distortion of peripheral objects due to spherical aberration and existance of a blind area due to prismatic deviation at the periphery of the lens which give rise to a ring-scotoma, both of which phenomena are much more accentuated on moving the eyes. As a result of these optical conditions the aphakic is rarely comfortable initially if the refractive condition is corrected by spectacles. It is true that some patients accept their new visual world rapidly and almost without complaints; but it is equally true that others of a less adaptable or more neurotic type are never able to reconcile themselves to them, remain copletely disoriented and distressed. The majority, however, are faced with a real problem in visual rehabilitation which can only be solved by a considerable amount of intelligent determination over some months. Many of these disadvantages - the impossibility of binocular vision, the limitation of the field, and so on - can be overcome, with some risk, if a plastic lens of a suitagle strength is inserted intra-ocularly, or more safely and easily, if contact glasses are employed instead of spectacle lenses; these however, are often not easily manipulated or worn by the average patient requiring surgery for senile cataract.