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PubMed1985

Diagnosis and management of lost muscle following strabismus surgery.

Of all the complications of strabismus surgery, the lost muscle is one of the most alarming, and yet with patience and careful management it may be one of the most amenable to treatment. This paper reports seven cases of lost muscle following strabismus surgery. In six of the seven cases referred to the Department of Clinical Ophthalmology there had been delay in diagnosis for periods varying from six weeks to 17 years. All the lost muscles were successfully retrieved. With good illumination and magnification and a careful search of the sub-Tenon's capsule space it is unusual to need to explore the orbital fat to retrieve the muscle.

Adolescent↗

PubMed2006

A surgical technique with connective tissue repair for the management of subconjunctival orbital fat prolapse.

Abstract Subconjunctival orbital fat prolapse is an uncommon benign entity. In addition to insufficient information concerning the mechanisms of the prolapse, detailed surgical methods that can be followed are uncommon in the literature. We prospectively studied six consecutive eyes in four males who were to undergo our novel surgical sequence, attempting to avoid postoperative complications by reconstructing intermuscular septa on the basis of the assumption that the spontaneous prolapsed fat at the superior temporal quadrant stemmed from intraconal fat. Intraoperative findings were in agreement with our hypothesis that the anterior part of the herniated fat is covered by both the intermuscular septum and Tenon's capsule. All the surgeries were uneventful and cosmetic improvement without postoperative complications was obtained. Our early results indicated the safety and efficacy of this newly developed technique for spontaneous orbital fat prolapse.

Adipose Tissue↗

PubMed1997

Nonsurgical and surgical methods of sclera reinforcement in progressive myopia.

PURPOSE: As shown by the clinical picture of progressive myopia, derangements in biomechanical properties of sclera may be more or less manifested. The study aims at the development of a discriminating approach to their correction. METHODS: Patients with the condition were given a sclera strengthening injection, in which a dose of liquid polymeric composition is injected under the Tenon's capsule on the scleral surface. After polymerization, the composition forms over the scleral surface a layer of elastic foamed gel. RESULTS: Complex experiments on 146 rabbit eyes showed that the injected material promotes collagen formation. Gradually dissolving, the gel stimulates the growth of connective tissue on the surface of the sclera, whose stress-strain parameters improve. A thorough clinical study of 240 eyes of patients aged 8-25 years with progressive 6-10 D myopia showed that the refraction remained stable in 79.6% eyes 1 year after the sclera strengthening injection and in 52.9% cases 4-9 years after the sclera strengthening injection. At the same time, fellow intact eyes have shown, respectively, 40.3% and 13.3% of myopia stabilization, and 212 untreated eyes of the control group 26.0% and 11.1%, respectively. 612 children and adolescents with high myopia and a yearly progression of over 1.0 D were subjected to a scleroplastic operation. It was found that the myopia remained stable in 95.7% cases 1 year after the operation, and in 71.9%, 7 years after the operation. If myopia progression continued after a sclera strengthening injection or scleroplasty, a second procedure was performed. Second interventions were effected on 118 eyes of 102 patients, including 42 eyes where a sclera strengthening injection followed a sclera strengthening injection, 27 eyes where scleroplasty followed a sclera strengthening injection, 31 eyes where a sclera strengthening injection followed scleroplasty, and 18 eyes on which a second scleroplasty was performed. Second interventions provide a double decrease of myopia progression rate and, in 63% of patients, stop the progression altogether. CONCLUSION: It can be concluded that nonsurgical and surgical techniques of correcting the biomechanical properties of sclera for the treatment of progressive myopia as well as discriminative methods of determining the indications to these procedures have proven to be effective.

Acrylamides↗

PubMed2005

Trypan blue identifies antimetabolite treatment area in trabeculectomy.

AIM: Colourless solutions of mitomycin C (MMC) and 5-fluorouracil (5-FU) are widely used during trabeculectomy to inhibit postoperative scarring. The poor visibility of these agents on the eye has several drawbacks including the inability to accurately assess the area of treatment. This study examined the utility of using trypan blue dye to colour antimetabolites used during trabeculectomy and the effect of trypan blue on antimetabolite cytotoxicity in vitro. METHODS: For in vitro experiments, MMC (0.4 mg/ml) and 5-FU (25 mg/ml) were reconstituted with or without trypan blue. A lactate dehydrogenase release assay was used to measure drug induced cell death and viable cell number 7 days after treatment. For clinical assessment, trypan blue 0.1% was added to MMC and 5-FU to final concentrations of between 0.01% and 0.05%. The mixture was applied to Tenon's capsule and sclera via pre-wet or into dry 5x8 mm sponges (MMC and 5-FU) for 3 minutes or by direct subconjunctival injection after completion of surgery (5-FU). Twenty two consecutive patients undergoing trabeculectomy either with or without trypan blue were followed for 2 years postoperatively. RESULTS: The addition of 0.05% trypan blue to MMC or 5-FU did not alter MMC induced cell death or the number of viable fibroblast in vitro. In vivo, trypan blue clearly delineated the antimetabolite treatment area and facilitated control of excess antimetabolite at the wound margins as well as sponge removal. With direct subconjunctival injection, total staining area varied for a given volume with location of the needle tip. Any leakage from the injection site could be easily seen. No adverse effects attributable to trypan blue were found in 2 years of follow up. CONCLUSIONS: Trypan blue permits delineation of antimetabolite/tissue interactions without affecting cytoxicity for the assays investigated. Trypan blue can be used to visualise antimetabolite soaked sponges, estimate treatment area, and show areas of unintended tissue contact during trabeculectomy. The addition of trypan blue to antimetabolites has potential benefits in clinical, research, and teaching aspects of ocular surgery and therapy.

Aged↗

PubMed1978

The surgical treatment of open-angle glaucoma in Nigerians.

The results of trabeculectomy and sclerectomy procedures for open-angle glaucoma in African Negroes are compared. Trabeculectomy produced fewer long-term complications, but otherwise there was little difference in their results. Excision of Tenon's capsule and the use of local corticosteroids postoperatively are probably significant in preventing failure of aqueous drainage from subconjunctival fibrosis.

Glaucoma↗

PubMed1989

A net for extending the optic nerve at enucleation of the eyeball.

A long section of optic nerve can be obtained during enucleation, when the eyeball is caught in a net made specifically for this purpose. The net is knitted from surgical thread and is in the shape of a barrel with two openings: one wide, one narrow. Separate thread is wrapped around the edge of the wide opening. When the eyeball is freed from the extrinsic muscles and Tenon's capsule, it is drawn into the net, and the wide opening is closed round the optic nerve. At the narrow opening there are three slip-knots by which the net is pulled forward and out of the orbit. Then the optic nerve is exposed and the surgeon is able to cut it close to the apex of the orbit. The length of severed optic nerve amounts as a rule to about 15 mm or more, depending on the age of patient.

Eye Enucleation↗

PubMed1991

Transpalpebral extrusion of a silicone sponge exoplant.

We report an unusual case of scleral buckle extrusion in a 63-year-old woman. A 5 mm silicone sponge exoplant eroded through Tenon's capsule, conjunctiva, and full-thickness upper eyelid, traversing the tarsal plate.

Eyelids↗

PubMed1997

Trabeculectomy with intraoperative sponge 5-fluorouracil in Afro-Caribbeans.

AIM: To study the efficacy and safety of intraoperative 5-fluorouracil (5-FU) in Afro-Caribbean patients. METHODS: The results of trabeculectomy in 18 eyes of 18 Afro-Caribbean patients in whom a sponge soaked in 25 mg/ml solution of 5-FU was applied between Tenon's capsule and sclera for 5 minutes before excision of the trabecula were compared with 16 eyes of 16 Afro-Caribbean patients matched for age, quantity, and duration of preoperative medications, who underwent trabeculectomy without 5-FU. RESULTS: The mean postoperative intraocular pressure (IOP) at 1 month was 15.6 (SD 6.1) mm Hg in the 5-FU group and 18.0 (5.2) mm Hg in the control group (p = 0.15). There was no significant difference in the IOP at 6, 12, 15, 18, and 24 months in the two groups. Success rate at 18 months defined as an IOP less than or equal to 21 mm Hg with no adjunctive medication was 56% in the 5-FU group and 55% in the control group. No major complications were noted in either group. CONCLUSION: Intraoperative sponge 5-FU alone is safe but does not appear to decrease the risk of failure of trabeculectomy in Afro-Caribbeans.

Administration, Topical↗

PubMed2002

A new delivery system for 5-fluorouracil using prodrug and converting enzyme.

AIMS: To evaluate a new delivery system of 5-fluorouracil (5-FU) using 5-fluorocytosine (5-FC) as a prodrug and cytosine deaminase induced in vitro and in vivo. METHODS: Fibroblastic cells from rabbit Tenon's capsule were cultured. The cells were exposed to 5-FU and 5-FC with or without cytosine deaminase induced by recombinant adenovirus. In the in vitro study, cell proliferation and DNA synthesis were assessed by MTS, BrdU assay. The effect of 5-FC removal after the treatment of 5-FC and cytosine deaminase induction was also assayed. In the in vivo study cells with or without cytosine deaminase induction were transplanted into the subconjunctival space of mice, followed by eye drops of 1000 microg/ml of 5-FC three times a day. The mice were sacrificed at days 1, 5, and 10, then the cells transplanted were evaluated. RESULTS: Cell proliferation was inhibited by exposure to 5-FU in a dose dependent manner; however, up to 1000 microg/ml of 5-FC did not affect cell proliferation. Cell proliferation was inhibited by exposure to 5-FC in a time dependent manner with induction of cytosine deaminase following infection of recombinant adenovirus. When 5-FC was removed 3 or 6 days after the treatment, the cells grew again. The effect was reproduced in the in vivo model of subconjunctival cellular proliferation although 5-FC was administrated as eye drops. There were no cases with corneal erosion. CONCLUSION: Cell proliferation was inhibited by co-exposure of 5-FC and cytosine deaminase. This new delivery system may merit controlled delivery of 5-FU after filtering surgery.

Animals↗

PubMed1975

Extraocular observations in episcleral sponge implants.

The follow-up of 262 cases of retinal detachment operated on after the Custodis-Lincoff method in combination with cryopexy permitted the following observations: (1) The implant protruded in a number of cases under an intact conjunctiva and Tenon's capsule without discomfort to the patient. This protrusion depended mainly on the size and the manner of fixation of the implant, the distance of the point of fixation from the limbus and the condition of the conjunctiva. (2) Changes were observed in the conjunctiva in the fixation area, such as subconjunctival haemorrhage, cystoid degeneration of the conjunctiva and rupture with extrusion of the sponge. Subconjunctival haemorrhages were observed in 3.4% of the cases and were either absorbed or led to an inflammation. Cystoid degenerations occurred in 2.2% of our cases. These were limited to the edge of the sponge proximate to the limbus and involved only cases of radial fixation. Rupture of the conjuctiva and extrusion were noticed in 3.4% of the cases. (3) An inflammation due to the sponge was observed in 4.1% of the cases. Its time of onset varied between 3 days and 22 months. According to the time of onset the patients were divided into three groups. The gravity of the inflammation was proportionate to the earliness of the time of onset. Predisposing factors for the above complications were mentioned and discussed.

Conjunctiva↗

PubMed1987

Complications after modern filter operations in glaucoma.

As long as the indications and limitations of laser trabeculoplasty have not yet been established by follow-up over several years, conventional surgical filter operation will not be superfluous. The reduction of the complications brought about by introduction of the scleral flap technique is described. Apart from cicatricial obliteration of the filtering zone, bulbar hypotension due to overfiltration as well as to external fistula and above all the resulting ciliary body-choroid detachment still occurs after trephination with the scleral flap (goniotrephination, trabeculectomy). Attention is drawn to the tension of the scleral flap adapted to the normalized intraocular pressure and reliable preclusion of an external fistula by perfusion test at the end of the operation. The membrane formation probably deriving from the internal Tenon's capsule which leads to a 'pseudofiltering bleb' is discussed as a rare complication (1.5%) which is of basic interest.

Cicatrix↗

PubMed2006

Stability of gold bead tissue markers.

Significant soft tissue features in the orbit and elsewhere are not resolved by MRI or any other imaging method. We describe a new method that uses tiny ( approximately 0.1 mm diameter) gold beads as markers to visualize movements of such tissues with high spatial resolution ( approximately 100 microm) and moderate temporal resolution ( approximately 100 ms). We describe bead fabrication, implantation, imaging, and image processing to extract three-dimensional bead coordinates. We then present results of an experiment to determine the stability of gold bead tissue markers (GBTMs) over time in normally moving orbital tissues. Most beads (76%) implanted in sclera, muscle, tendon, and connective tissue were highly stable over the 6-month measurement period. Beads that were judged unstable drifted only a few 100 microm. Bead flows with gaze suggested that posterior Tenon's capsule moves with the globe, that the lateral rectus belly may sideslip, producing "bridle forces," and that the posterior medial rectus pulley sling moves freely anteriorly and posteriorly, but hardly vertically, as required by the "coordinated active pulley" hypothesis. The GBTM method seems applicable to study such short time course phenomena as extraocular muscle (EOM) and connective tissue movement as a function of gaze and such long time course phenomena as myopic eye growth.

Animals↗

PubMed2006

Extraocular connective tissues: a role in human eye movements?

PURPOSE: This study presents a detailed anatomic analysis of the undisturbed connective tissues that surround the horizontal extraocular muscles (EOMs) of humans. Emphasis is placed on those EOM orbital side tissues that, in previous MRI studies, were assumed to couple the muscle to the pulley. METHODS: Serial 5-mum sections were prepared from paraffin-embedded blocks of the lateral and medial rectus muscles and their surrounding connective tissues. The sections were treated with Masson's trichrome stain for light microscopic examination of muscle fibers (red) and surrounding connective tissues (blue). RESULTS: Rectus muscle sections demonstrated the orbital connective tissues to be a collagenous bridge between the distal third of the muscle and the orbital periosteum (i.e., check ligament [CL]). The CL attaches to the muscle by investing itself around orbital muscle fibers whereas, at the point of attachment, those fibers remain aligned with the remainder of the muscle. The CL on the orbital side and the reflected bulbar fascia on the global side of the muscle constitute a tubelike sheath. The posterior border of the sheath insinuates into the muscle belly and its anterior aspect blends into the sides of the portal through Tenon's capsule. CONCLUSIONS: All rectus EOM fibers participate in eye rotation. The CL is the band of tissue present on the MRI images, but was previously described as the orbital layer insertion for the active pulley hypothesis (APH). The APH should now be questioned. Alternate theories incorporating accepted neurophysiological, anatomic, and ophthalmological principles of EOM movement are discussed.

Aged↗

PubMed1990

Antiproliferative drugs and human ocular fibroblasts: colorimetric vs. cell counting assays.

Utilizing a rapid colorimetric assay that relates cell number to cytoplasmic hexosaminidase activity, we conducted drug-induced cytotoxicity experiments on human ocular fibroblasts cultured from Tenon's capsule specimens. The effects of two different agents--dimethyl sulfoxide (DMSO) or mitomycin C--on the proliferation of human ocular fibroblasts were studied. Simultaneously the sensitivity of this technique was compared to electronic cell counting with a Coulter counter, a conventional means of quantifying proliferation. Known numbers of cells were exposed to varied concentrations of either DMSO or mitomycin C for 11 days. Cell attachment was quantified after 24 hours, and proliferation was quantified periodically thereafter over the remaining 10 days. Colorimetric data contained a similar or smaller amount of random error than corresponding Coulter values. Both assays identified statistically significant antiproliferative effects and inhibitory effects on cell attachment at higher drug doses; however, Coulter counting alone detected many additional significant effects among lower-dose DMSO and mitomycin treatment groups. Although the hexosaminidase assay displayed lower sensitivity than Coulter counting, it may still be useful to rapidly screen new compounds for strong antifibroblastic effects.

Cell Adhesion↗

PubMedDate not supplied

B-scan ocular ultrasonography in preterm and term infants.

PURPOSE: To evaluate the normal B-scan ocular ultrasonographic findings in preterm and term newborns. This information would be useful in making perinatal ocular diagnoses, especially in consideration of the rapidly changing eyes of normal infants shortly after birth. METHODS: One hundred two healthy infants aged 28 to 48 weeks postconception were prospectively studied. Eighty-six had complete sonograms, while others had incomplete examinations due to systemic instability. B-scan ultrasonography was conducted through acoustic coupling medium and a closed eyelid using the Coopervision Ultrascan 404 unit. The ultrasound findings were evaluated relative to the infant's postconceptional age and weight at examination and the axial lengths of each eye. The ultrasonographer, who determined the presence of abnormal findings, was masked to the parameters mentioned above. RESULTS: Four specific findings frequently were noted in newborns that would be considered abnormal in adult eyes. These were: 1) a visible Tenon's capsule; 2) prominent superior ophthalmic vein; 3) sonolucent extraocular muscles; and 4) vitreous opacities. These findings were more common in the more premature infants (P < 0.01 by t test). CONCLUSIONS: The presence of these four ultrasonographic findings in the eyes of infants should be considered normal, and should not necessarily prompt further work up until after the perinatal period.

Adult↗

PubMedDate not supplied

Giant orbital cyst as a complication of a slipped medial rectus muscle.

A 61-year-old woman presented with painless swelling in the right medial orbit. There was a history of complicated squint surgery at 9 years of age, with a slipped right medial rectus and subsequent exotropia. A retention cyst in the Tenon's capsule of the slipped medial rectus was confirmed by magnetic resonance imaging.

Cysts↗

PubMed2000

Overexpression of MMP-1 and MMP-3 by cultured conjunctivochalasis fibroblasts.

PURPOSE: To determine whether conjunctivochalasis, denoting redundant, loose, nonedematous inferior bulbar conjunctiva, is associated with increased expression and activity of matrix metalloproteinases (MMPS) over their tissue inhibitors (TIMPs). METHODS: Expression of transcripts and proteins of MMPs, TIMPs, and urokinase plasminogen activator (uPA) by cultured normal human conjunctival and conjunctivochalasis fibroblasts was determined by Northern hybridization, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis, respectively. Gelatin and casein zymography and quantitative collagenase activity assay were performed in the serum-free conditioned media. RESULTS: Compared with normal conjunctival fibroblasts from six subjects, conjunctivochalasis fibroblasts from eight patients showed markedly increased transcript expression of MMP-1 (5- to 32-fold) and MMP-3 (4 to 30-fold), whereas that of MMP-2, TIMP-1, TIMP-2, and uPA was similar between the two groups. Protein levels were increased in the serum-free conditioned media of conjunctivochalasis fibroblasts for MMP-1 (3.5- to 7.6-fold) and MMP-3 (2.3- to 13-fold), determined by ELISA and Western blot analysis. There was increased caseinolytic activity of MMP-3 and collagenolytic activity of MMP-1 (2.2-fold) by conjunctivochalasis fibroblasts, whereas no difference was noted between these two types of fibroblasts in the protein and gelatinolytic activity of MMP-2 or expression of TIMP-1 and TIMP-2 proteins, although that of TIMP-1 transcript was slightly higher in some conjunctivochalasis fibroblasts. No expression of MMP-9 was detected. CONCLUSIONS: Overexpression of MMP-1 and MMP-3 mRNA by conjunctivochalasis fibroblasts is correlated with their increased protein levels and proteolytic activities. Collectively, these data help explain how conjunctivochalasis manifests excessive degradation of the conjunctival matrix and Tenon's capsule.

Blotting, Northern↗

PubMed2000

S-nitrosoglutathione photolysis as a novel therapy for antifibrosis in filtration surgery.

PURPOSE: To determine whether a novel peroxynitrite-based photosensitizer S-nitrosoglutathione (GSNO) can produce specific in vitro light-induced cell death of both standard animal lung and human Tenon's capsule (TC) fibroblasts and to compare this effect with that produced by the established photodynamic porphyrin precursor 5-aminolevulinic acid (ALA). METHODS: V79-4 Chinese hamster lung and human TC fibroblasts were established in tissue culture. GSNO, together with its radioactive tritiated and fluorescent dansylated derivatives, were synthesized. The labeled molecules were prepared to determine the time course of uptake into the fibroblasts. Uptake was monitored by scintillation counting for the tritiated GSNO and confocal fluorescence microscopy for the dansylated GSNO. The uptake of ALA and biosynthesis of its photosensitive product were determined by fluorescence emission spectroscopy of a separate set of fibroblasts. Once uptake was established, both cell lines were incubated with varying concentrations of GSNO or ALA as a function of time (0, 4, or 24 hours) before light exposure (200 msec pulsed visible light, 0.068 W per pulse, for 10 minutes at a distance of 10 cm). After 10 minutes of irradiation, the cells were washed and exposed to fresh tissue culture medium. The effect of the treatment was determined 24 hours later by measuring cell viability. RESULTS: A 2-minute drug treatment time (0 hours incubation) with GSNO, followed by 10 minutes of irradiation, resulted in approximately 78% of fibroblast cell death at the lowest concentration of GSNO used compared with the control, which was exposed to light, but no GSNO. The higher concentrations of GSNO, or longer drug treatment times before irradiation, did not statistically increase cell death. Maximal cell death was thus obtained using the lowest GSNO concentration (50 mM) and drug treatment time (2 minutes). In contrast, the well-established photosensitizer ALA killed only approximately 4% of cells at the lowest concentration and drug treatment time tested. At drug treatment times of 4 hours and less, increased concentrations of ALA did not produce cell death of more statistical significance. It was not until 24 hours of drug treatment that comparable amounts of cell death were produced by ALA and GSNO. In all experiments similar results were obtained with the animal lung and human TC fibroblasts, suggesting that the source of the fibroblast had no effect on the outcome. The differences in treatment effects between GSNO and ALA were statistically significant under all conditions tested. CONCLUSIONS: GSNO is able to cause light-specific cell death of human TC fibroblasts at drug treatment times (2 minutes) and irradiation times (10 minutes) that would be compatible with its use in glaucoma filtering surgery. This in vitro performance was superior to that of the well-established photosensitizer ALA, which required treatment times longer than 4 hours to approach the light-specific cell death produced by only 2 minutes of GSNO treatment.

Aminolevulinic Acid↗