Diamond-like carbon coating and plasma or glow discharge treatment of mechanical heart valves.

All mechanical heart valves (MHV) are thrombogenic. Application of surface modification technology to reduce the incidence of thrombus formation on MHV is a novel undertaking. This requires collaboration within the bioengineering and cardiothoracic surgery fields. From reviewing results of recent and past investigations, and our own preliminary study with diamond-like carbon coating (DLC) and plasma or glow discharge treatment (GDT) of MHV, we identify and discuss several potentially beneficial effects that may reduce the extent of valve-related thrombogenesis by surface modification. DLC and GDT may affect the surfaces of MHV in many ways, including cleaning of organic and inorganic debris, generating reactive and functional groups on the surface layers without affecting their bulk properties, and making the surfaces more adherent to endothelial cells and albumin and less adherent to platelets. These different effects of surface modification, separately or in combination, may transform the surfaces of MHV to be more thromboresistant in the vascular system.

Management of the paralyzed lower eyelid by implanting auricular cartilage.

The success of a procedure to reanimate paralyzed eyelids is determined by the functional and cosmetic results. When the cornea is covered during blinking and sleeping, function has been restored, while a pleasing cosmetic result has been achieved if the eyes appear symmetrical when the lids are open. Several procedures have been developed to restore closure of the paralyzed upper eyelid (implantation of gold weights or open wire springs) or to correct lower lid lagophthalmos and ectropion (lower lid tightening with a Bick procedure or insertion of a closed eyelid spring). In some cases, even a combination of the Bick procedure and insertion of a spring may be insufficient to correct lower lid droop; therefore, we developed a technique to place cartilage into the lower eyelid to correct lid droop. The procedure, suggested by one of us (D.B.S.), has been performed on 51 patients to date. This article reviews our experience with these 51 consecutive patients.

Kaposi's sarcoma of the eyelid as the initial manifestation of AIDS.

Early recognition and identification of acquired immune deficiency syndrome (AIDS) ocular manifestations are mandatory if proper precautions are to be taken. Kaposi's sarcoma is a well-known manifestation of the disease; however, the initial presentation of the lesion on the eyelid is rare. Such a case is presented in order to alert ophthalmologists to this. It is suggested that all eyelid lesions in suspect patients should be regarded as potentially related to AIDS.

Cataract surgical suture marking device for the intraoperative control of astigmatism.

A new device for the intraoperative monitoring of astigmatism is described. Use of the instrument enables the surgeon to position the closing sutures precisely and minimize astigmatic errors often induced at closure.

New surgical approaches to the management of ocular exposure secondary to facial paralysis.

Restoring dynamic eyelid function in patients who experience facial paralysis is a difficult problem. Some procedures necessary to protect the globe, such as tarsorrhaphies, may be cosmetically disfiguring and functionally disabling. Several surgical procedures may be used in combination to restore function and, at the same time, achieve satisfactory cosmesis. The use of gold weights and ear cartilage grafts is described. In the author's experience, the use of this combination produces very good results.

Evisceration with eversion of the scleral shell and muscle cone positioning of the implant.

Six patients underwent a new surgical procedure to repair extruding evisceration implants. The scleral shell was everted and used as an anterior wall for the placement of a donor sclera-encased implant within the muscle cone. Early results showed good cosmesis and no recurrent extrusions.

Methotrexate-anticollagen conjugate inhibits in vitro lens cell outgrowth.

After-cataract, or posterior lens capsule opacification, is an undesirable but common sequela to extracapsular cataract surgery. We are investigating biochemical means to prevent after-cataract formation, which can be applied at the time of the original surgery. Based on similar research efforts in cancer chemotherapy, we have prepared a conjugate of the antimetabolic agent methotrexate with an antibody specific for basement membrane collagen, the major protein in the lens capsule. The conjugate was evaluated using biochemical measurements, and retained both antimetabolic and antibody activities. When the conjugate was applied to bovine posterior capsules in vitro, or in vivo in rabbits, it was an effective inhibitor of lens epithelial cell outgrowth in cell culture.

Vein grafting in nasolacrimal system reconstruction.

Obliteration of the tract after conjunctivodacryocystorhinostomy is one of the main complications associated with the procedure. The use of a saphenous vein graft which covers the tube may aid in establishing an immediate lined tract for the tube when performing a conjunctivodacryocystorhinostomy. Another possible use for the vein graft is in anastomosing the parotid duct to the inferior cul-de-sac when performing a parotid duct transfer. The vein graft makes parotid duct transfer easier and helps control the amount of saliva delivered to the eye. A case report is presented.

A new and effective protective agent for intraocular lens insertion.

Chondroitin sulfate (CDS) has been found to serve as an excellent protective coating for intraocular lens (IOL) implantation to avoid any damage to the corneal endothelium; the protection is total. Using a new vital dye, acid violet 49, as a stain, a series of possible coatings including albumin and hyaluronic acid was evaluated in vitro and in vivo. Some 600 animal corneas were trephined, and the sample buttons submitted to the dragging of variously coated lenses across the endothelium. The animal species were rabbit, pig, cow, dog, cat, and monkey. IOLs were traumatically inserted in rabbits and monkeys. Chondroitin sulfate surpassed by far the protective qualities of other compounds: albumin was second best; hyaluronic acid third, the latter two yielding substantial damage in our tests. Comparisons with the commercially available Healon still revealed chondroitin sulfate to be the most efficacious protective agent. The material was eliminated from the anterior chamber in periods less than 40 hours. Monitoring of postoperative intraocular pressures revealed only normal pressures in our animals.

The anophthalmic socket.

Following enucleation or evisceration surgery, the anatomy and physiology of the orbit are changed. These changes affect not only the cosmetic appearance of the anophthalmic patient but also the function of the socket and the prosthesis. Surgical techniques for primary enucleation and evisceration surgery and correction of early and late complications are described. During the course of this century many operations and prosthetic devices have been advocated. A brief summary of these is given as well as detailed surgical descriptions of techniques the author believes have proven successful over the years.

Evaluation of timolol in chronic open-angle glaucoma. Once a day vs twice a day.

Regimens of once-a-day or twice-a-day 0.25% timolol ophthalmic solution were compared for efficacy and tolerability in a four-week study of 41 patients with chronic open-angle glaucoma and elevated, untreated intraocular pressure. Significant reductions in IOP relative to untreated baseline values were achieved within a range of 18% to 25%. No significant between-group differences were noted, although the twice-a-day group had somewhat lower IOPs at each evaluation point and the once-a-day group had somewhat fewer subjective symptoms of local irritation. A statistically significant decrease from baseline in mean pulse rate was noted in the twice-a-day treatment group after two weeks; no clinically significant or serious adverse reactions occurred in any patient. Both once-daily and twice-daily administrations of 0.25% timolol ophthalmic solution were found to be effective and well tolerated in the population studied.

Evaluation and protection of corneal endothelium.

A series of experiments was performed in vitro, on animal and human corneas, and in vivo, on monkeys and rabbits, to test the efficacy of various substances which may be used as coatings for intraocular lenses to protect the corneal endothelium from damage. The vital dye, acid violet 49, was applied to evaluate endothelial cell function and damage. Our results indicate that chondroitin sulphate is far superior to other substances tested in preventing endothelial damage due to intraocular lens contact. Acid violet 49 is very sensitive in detecting endothelial cell damage, and the intensity of cellular staining with acid violet 49 correlates well with the degree of endothelial cell damage.

Primary choroidal and cutaneous melanomas occurring in a patient with the B-K mole syndrome phenotype.

A patient with malignant melanoma of the choroid and ciliary body had a primary cutaneous melanoma and the B-K mole syndrome phenotype. Because of this newly described association, all patients with the B-K mole syndrome (phenotype) should have a complete ocular examination to discover if there is any evidence of ocular melanoma. Likewise, all patients with ocular melanoma should have a thorough dermatologic examination to determine evidence of cutaneous melanoma and the B-K mole syndrome (phenotype).

Basic concepts and an overview of cryosurgery in ophthalmic plastic surgery.

In cryosurgery, a rapid double freeze using liquid nitrogen spray coupled with a slow thaw generates optimum cell destruction. Important factors in using the cryosurgical technique include temperature monitoring of the lesion, the type of instrumentation, the type of cryogen, and the nonhomogeneity of human tissue. Physiological processes occurring subsequent to cryogen application cause tissue necrosis. Cryosurgery is indicated for treatment of some basal cell carcinomas and occasional squamous cell carcinomas; most other lesions should be treated by surgical excision at the present time. The authors are involved in research to determine means of observing tissue destruction, temperature monitoring and control methods, and evaluation of post-thawing processes.