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This new knife handle is designed for all Bard-Parker blades. It safely releases the blade through a mechanism that is intended to reduce the risk of injury and subsequent infection by blood-borne pathogens.

Safely suturing a posterior chamber intraocular lens (PC-IOL) to the ciliary sulcus requires a means of visualizing the ciliary sulcus, since it cannot be viewed directly with the operating microscope. We, therefore, created several trial instruments consisting of a mirror with a built-in light source, which we call an endo-mirror, designed for observing the area behind the iris. Using these instruments, we were able satisfactorily to view the ciliary sulcus and suture a PC-IOL to it, first in a number of animal eyes, and then, using an endo-mirror incorporating the best features of the trial versions, in actual clinical cases.

The Hyde astigmatic ruler is an inexpensive, semiquantitative, hand-held, surgical keratometer that we modified by geometrically calculating the correct shape of its ellipses. The Barrett keratoscope is a cheap, disposable, qualitative keratometer that, unlike the Hyde ruler, produces a bright corneal image. We designed a transparent overlay, or "astigmatic dial," to use with the keratoscope. This overlay determines the magnitude of astigmatism and sets the distance the keratoscope is held from the cornea by direct comparison with the corneal image. Using a model cornea, we compared our modified Hyde ruler with the Barrett keratoscope and astigmatic dial to determine the accuracy of measurement provided by each. Both instruments had good predictive values for the true astigmatism; however, the Barrett keratoscope/astigmatic dial provided more consistent measurements of the astigmatism. We believe the keratoscope and dial provide a cheap, convenient, and accurate alternative to the more expensive microscope-mounted keratometers.

Intraoperative keratometry allows some degree of control over corneal astigmatism during cataract surgery. I describe the clinical use of the Barrett keratoscope combined with an astigmatic dial that quantifies the information obtained by this simple, inexpensive, hand-held surgical keratometer. Based on a comparison of intraoperative measurements with those taken after extracapsular cataract surgery with an automated keratometer, I conclude that intraoperative keratometry reliably predicted the postoperative astigmatism. For those who had the intraocular pressure (IOP) set between 15 and 20 mm Hg intraoperatively, the mean deviation of the first postoperative measurement from the intraoperative measurement of astigmatism was +/- 1.03 D (standard error, 1.56 diopters; 95% confidence interval 0.712 to 1.35 D). When the IOP was not set, the postoperative astigmatism differed from the intraoperative reading by more than 2.00 D for 50% of the cases. Setting the IOP prior to intraoperative keratometry significantly improved the reliability of the measurement. Intraoperative keratometry by the simple device used in this study is of sufficient utility to allow the surgeon to adjust for the predicted changes in the corneal astigmatism at the time of surgery.

Successful retinal detachment surgery is greatly aided by proper visualization of and access to the intended surgical field. Two retractors, one having a single blade and the other a double blade, have been developed to aid retinal detachment surgery.

We describe a new instrument, the Reiss punctal punch, which is specifically designed to performa "wedge" punctoplasty. The Reiss punctal punch was used alone to treat three eyelids of three patients, and in conjunction with horizontal tightening of the eyelid to treat 35 eyelids of 18 patients with symptomatic epiphora related to punctal ectropion with secondary punctal stenosis. After a mean follow up of 12 months, 36/38 (95%) of the eyelids demonstrated a patent punctum, and symptomatic relief was achieved in 35/38 (92%) of the eyes.

We present an endoscope designed for ophthalmic microsurgery. The handpiece contains a charge-coupled device, a solid-state imager (250,000 pixels), and a probe (either 0.89 or 1.5 mm in diameter), including the light guide. The light source is a halogen lamp. The clear views the instrument provides of the ciliary sulcus and ciliary body behind the iris make it useful in secondary posterior chamber intraocular lens implantation using the ciliary sulcus suturing technique, and in endolaser photocoagulation of the ciliary body in end-stage glaucoma. It also is useful in performing vitrectomy in cases in which visualization is difficult because of corneal opacification or fluid-gas exchange.

In exophthalmometry when the lateral orbital rim is used as the instrument's fixation base, any alteration in the rim will render serial measurements inaccurate. The exophthalmometer we describe (technically, an "orbitometer") uses the superior and inferior orbital rim areas as a base of reference, making it particularly useful in lateral orbitotomy procedures. This instrument can be aligned at the midpupil horizontally and vertically with a vertical fixation bar. In addition, a vertical bar gradient scale allows measurement of hypoophthalmos and hyperophthalmos.

The effect of needle length on the efficacy of regional ophthalmic anesthesia in conjunction with cataract surgery was studied in 97 patients using a two-site injection technique. The local anesthetic used was etidocaine 1.5% with hyaluronidase. In 48 patients, the anesthetic was administered inferolaterally with a 22-millimeter needle, and in the other 49 patients, with a 31-millimeter needle. Every patient had a medial injection with a 12-millimeter needle to achieve lid akinesia and to complete the globe akinesia. At 5 minutes, lid akinesia was considered better in the 22-millimeter needle group (P < .005). After one supplemental dose, when necessary, complete globe akinesia was achieved at 15 minutes significantly more often (94% vs 79%) in the 31-millimeter needle group (P < .05). Lid akinesia in the two groups was identical at that time. Eight patients in the short-needle group and three in the long-needle group experienced some pain during surgery. Throughout the study, the required intraorbital anesthetic volumes were smaller in the 31-millimeter needle group. We recommend the use of a 31-millimeter needle inferolaterally in combination with a 12-millimeter needle medially to achieve satisfactory regional anesthesia for cataract surgery.

Manual removal of the corneal epithelium currently precedes excimer laser photorefractive keratectomy. To assess the smoothness of the corneal surface following this procedure, six paired human eye-bank eyes (12 eyes) were manually deepithelialized using a blunt instrument (Paton spatula) on one eye and a sharp instrument (surgical blade) on the contralateral eye; all deepithelializations were done by the same surgeon. The 12 corneas were then resected and processed in an identical fashion for scanning electron microscopy. The microphotographs obtained showed that among the corneas deepithelialized with the blunt spatula, two had a smooth surface, and four had variable amounts of residual epithelial cells and basement membrane, confirmed by light microscopy. The surface of five corneas deepithelialized with the sharp instrument were slightly rougher than the former, with occasional linear scratches; one cornea retained a small amount of basement membrane. Removal of epithelium appears to be more complete when a sharp instrument is used. These findings may have clinical relevance, since residual epithelium and basement membrane after deepithelialization may influence the depth of ablation subsequently achieved with the excimer laser.

We have devised a method of single-eyelid canalicular reconstruction using the pigtail probe to facilitate identification of the proximal canalicular segment following silicone stent intubation of the normal, uninjured canaliculus. A series of seven acute and two long-standing canalicular lacerations were successfully reconstructed using this technique, which minimizes the risks associated with the use of the pigtail probe.

I have devised an easily-fashioned disposable "corneal cap" that reduces light exposure to the retina from the operating microscope. The 8-mm plastic cap is the cut end of the test chamber included in all packages of disposable handpieces and tubing for automated irrigation and aspiration instruments.

We present a new instrument designed to facilitate the microtrephination of tissues required in various ophthalmic procedures. This microtrephine is a 21-gauge stainless steel tube, 0.81 mm in diameter and 16 mm long, with a sharpened cutting end and a plastic finger-grip area to facilitate micro-rotation. A standard plastic luer hub allows the trephine to be used with a syringe, either a standard type or one with a spring-assisted plunger. Scar tissue, biopsy specimens, or abnormal inflammatory fluids can be suctioned into the syringe for subsequent pathologic examination.

The development of the single point cam guided cornea trephine frees the cornea surgeon from always cutting a round recipient window perpendicular to the visual axis of the eye. This new trephine allows for any angle of cut relative to the visual axis of the eye and any shaped window, be that window round, ellipse, oval or "other than round." Full development of the technique lies in the future with the development of more complete topographical measuring techniques and the integration of the measurement into a computer program wherein the computer controls the indexing of the blade cutting the recipient window and the angle of the blade while the blade is making the incision.

A newly modified endoillumination probe using the Ocutome handle has been developed that has 2.5 times more total light output and over four times more light intensity than the conventional endoillumination probe. The new probe is particularly useful in situations where there is extremely dense vitreous hemorrhage and when one requires additional light for 16-mm cinematography.

An ongoing study of pachymeters has been carried out to determine the accuracy, reproducibility, and ease of operation of various optical and ultrasonic pachymeters. Beginning with optical versus available ultrasonic pachymeters, the demonstrated greater accuracy and reproducibility of ultrasound led to enlargement of the study to a comparison of all available ultrasonic pachymeters. Side-by-side evaluation was undertaken to determine interobserver variation and a number of other factors. The results are summarized as a guide.

Forty patients with aphakic bullous keratopathy undergoing combined penetrating keratoplasty and anterior vitrectomy using mechanical vitreous instruments were studied for a mean length of 36 months. Seventy percent of the grafts remained clear and thirty percent failed during the follow-up period. Fifty-three percent of those with clear grafts (15/28) obtained a visual acuity of 20/70 or better. In comparison to older methods of anterior vitrectomy, we have found that removal of vitreous with mechanical vitreous instruments offers more effective removal of solid and liquid vitreous, decreased surgical time, and decreased retinal traction. Further, it is easy to learn to use and handle these instruments.

The glaucoma shell tamponade technique in filtering surgery for glaucoma is a technique for (1) decreasing the incidence of flat anterior chamber and choroidal separation postoperatively, (2) promoting the development of a low diffuse filtration area, and (3) increasing the possibility of achieving very low resulting postoperative pressure. The glaucoma shell technique is applicable to all types of filtration procedures, including conventional filtering procedures utilizing no scleral flap and those utilizing a scleral flap, such as trabeculectomy. It can be used at surgery or can be applied in the postoperative period to deal with flat or shallow anterior chambers immediately at the time of onset. The shell tamponade technique can be utilized to aid in the management of some cases of leaking bleb in the early postoperative period or in the late postoperative period. The technique for operative and postoperative use of the glaucoma shell tamponade technique and its closely related pressure dressing is a demanding and exacting art. Because the technique increases the possibility of very low resulting tensions, its use should be considered especially for cases in which very low pressures are desired, such as some cases of extremely advanced cupping and field loss and low-tension glaucoma.

Since it is impossible to sterilize the surgical field in ocular surgery, postoperative endophthalmitis remains a serious complication of intraocular surgery. The surgeon should take all reasonable precautions to avoid this disaster. We believe that this includes isolating the skin and eyelids from the operative field with the incise drape.

Following the retrobulbar injection of anesthetic, the application of a mechanical device to lower the intraocular pressure will produce a rise in intraocular pressure that may be sufficient to compromise ocular perfusion. To increase the margin of safety for ischemic damage, a mechanical means of intraocular pressure reduction (Superpinkie) was applied prior to, rather than following, the retrobulbar injection of anesthetic. The study group consisting of 20 patients receiving the compression-injection sequence had a mean preoperative pressure of 4.70 mm Hg, while a control group of 20 patients receiving the injection-compression sequence had a mean preoperative pressure of 2.25 mm Hg. The proposed compression-injection method was well tolerated by the patients and attained surgically adequate anesthesia, akinesia, and ocular opening pressures. In selective cases, the compression-injection technique for the delivery of retrobulbar anesthesia may offer a means of better maintaining ocular perfusion and thereby lessening the risk of vascular compromise.

Description of Grieshaber nibbler for closed vitreous surgery: tip diameter is 1.6 mm, cutting is by four exquisitely cutting blades mounted on axis supported at both ends. Control console determines mode and speed of rotation. Oscillating cutting mode is recommended. Infusion is at the instrument's tip instead of its side. Unusually powerful but adjustable endo-illumination is available through fiberoptics. The fiberoptics tip is shaped to facilitate its introduction into the eye. A separate channel permits suction reversal. Five brief case descriptions illustrate versatility of the instrument. Its main advantages are its exquisite cutting properties, its powerful and adjustable endo-illumination, and its tip-end infusion hole.

A fixed contact lens retaining ring with its own irrigation system is described for use in pars plana vitrectomy. The advantages and disadvantages of this system are compared with the hand-held contact lens instruments.

The shaping of swollen, abnormally hydrated donor corneal tissue on the cryolathe for use in keratorefractive surgery yields lenticules of insufficiently predictable dioptric powers. The irregular nature of this abnormal hydration precludes the use of mathematical compensating factors. To improve control over the shape of the lenticule, we have developed a cornea press which restores normal hydration and dimensions to the donor tissue by mechanical dehydration.

I have devised a superior rectus fixation forcep of heavy construction which can be used with ease in the field of the operating microscope.

A new corneal trephine has been described which allows the surgeon to see the circumference of the cutting edge, as well as most of the cornea, lens and iris, while looking through the operating microscope. The trephine has a 3-mm cutting ring supported by an open "branding iron" structure.

One hundred one cataract patients were tested preoperatively for macular function using the Flying Corpuscle Viewer, a portable blue field entoptic device which utilizes the slit lamp as a light source. Preoperative appreciation of the "Flying Leukocyte Corpuscles" (FLC) indicated a high probability of good postoperative visual acuity, while lack of appreciation of the blue field entoptic phenomenon preoperatively had no predictive value for postoperative visual acuity.

A new intraocular foreign body retriever especially suited for removal of small nonmagnetic foreign bodies was devised. Initial clinical trials have proved satisfactory, especially with vitreous surgery.

A pocket-sized self-illuminated diagnostic instrument is described which projects a series of white dots upon the cornea from the center to the periphery radially disposed in a fashion similar to an astigmatic dial. The battery-operated instrument allows for a rapid qualitative estimate of corneal astigmatism and the meridians involved.

Ophthalmologists working in developing nations are faced with shortages in surgical equipment and expendable supplies. Invention and improvisation can extend financial resources and reduce the unit cost per operation. Examples of appropriate ophthalmic technological invention are described and illustrated.

There are three basic needs for a vitrector or vitreophage. One is for the anterior segment surgeon so that he may have a machine available when vitreous is lost during anterior segment surgery and may spare himself the hazards and potential complications of doing vitrectomy solely with cellulose sponges. The simplified vitrector which is disposable, sterile, and rapidly made ready ideally serves this need in a way which is not served by any other technique. Two, the removal of normal vitreous may be necessary in patients with vitreous contact, and any type of vitreous removing machine may be useful for this. The vitrector we have worked with is simple and satisfactory, and has the potential advantage of having blades which are always sharp and always pushed firmly against the cutting edge of the hole since they are disposable and inexpensive. An infusor as well as simple cutting tips are available. Three, vitrectomy for serious vitreous pathology can be done with the simple vitrector through the anterior segment approach if the lens is absent or will be removed, and if heavy pre-retinal and vitreous bands are not present. For the handling of diabetic retinopathy and sheets of vitreous membranes which appear organized, other equipment may be superior.

A new needle and method have been developed for the administration of retrobulbar injections. The needle is curved as it extends from its hub, but it has a straight terminal portion. Use of this needle with the technique described should decrease the risk of most complications associated with conventional needles and techniques.

Two studies were carried out to determine and compare the effects of several sources of variation on the measurement of corneal thickness using the standard optical pachymeter and three ultrasonic pachymeters. Sources of variation included: intra- and inter-session variation, inter-observer variation, left/right eye variation, and variations due to alternate settings of ultrasonic sound frequencies. It was found that the optical pachymeter had a) two to three times as much intra-session variation as that of the ultrasound pachymeters, b) significant inter-observer variation (P = 0.015), and c) significant differences between left and right eye thickness determinations (P less than 0.005). On the other hand, ultrasonic pachymeters demonstrated a) high reproducibility, b) no inter-observer variation, and c) no left/right eye variation. These results have implications for the use of pachymetry in measuring corneal thickness for radial keratotomy and other refractive surgery.

A pocket-sized self-illuminated diagnostic instrument is described which projects a circle or a line, continuous or interrupted, upon the cornea. It is moved in all directions, thus rapidly scanning the cornea for any distortion of the reflected image, indicating or localizing surface or structural pathology.