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Biomedical subjects

D R Sanders

Publications and source records attributed to D R Sanders.

At least 91 records · Page 5Linked to original sources
PubMed1980

Specular microscopy in cataract and intraocular lens patients. A report of 564 cases.

We studied 564 patients who underwent cataract surgery, using preoperative and postoperative endothelial cell photographs and corneal thickness measurements. No statistically significant difference was noted in endothelial cell loss between patients with intracapsular cataract extraction (12.6%) and those undergoing posterior chamber phacoemulsification (15.2%). Both procedures had significantly less cell loss than with anterior chamber phacoemulsification (27.3%). Intraocular lens implantation produced a mean endothelial cell loss of 15.8% to 20.9%, depending on surgical technique and implant type. A Choyce-style lens resulted in statistically less cell loss than with other implants. Mean endothelial cell loss was 17.8% with clinically atraumatic and 27.3% with clinically traumatic implantations. Corneal thickness measurements did not correlate with endothelial cell loss or trauma observed clinically at the time of surgery and did not seem helpful in the preoperative evaluation of cataract cases.

Cataract Extraction↗
PubMed1980

Membrane formation after implantation of polyvinyl alcohol-coated intraocular lenses.

Two PVA-coated intraocular lenses were implanted. In the first case there was an acute onset of severe intraocular inflammation and dense membrane formation on the surface of the implant. The inflammation developed on the fifty-third postoperative day in a previously quiet eye. The second case demonstrated a relentless increase in intraocular inflammation that was unresponsive to medical therapy. An acute exacerbation with membrane formation occurred between the fortieth and forty-fifth postoperative days. In both cases the fibrinous membranes and the implants were removed with prompt resolution of symptoms.

Aged↗
PubMed1980

Computerization of intraocular lens data.

We have developed a method of computerization to collect intraocular lens research data in a private office practice. More than 30 separate variables are now being collected on all patients, and over 1300 cases have been studied. Information is transcribed from patient records to data sheets and typed directly into an office Teletype 43 terminal, which is connected by an acoustic coupler to an IBM 370-148 computer. The data are stored in a systems library which is equipped with an editing mode for rapid updating and addition of data. It also allows jobs to be submitted and returned through the remote terminal. The system is compatible with a statistical package which allows a wide range of statistical analyses.

Aged↗
PubMed1980

Improvement of intraocular lens power calculation using empirical data.

A simple lens power calculation formula of the form: Predicted implant power = A + B X axial length + C X keratometry, can be produced with different constants (A, B, and C) for each type of lens implant and each manufacturer. We have determined the constants for iris-fixated, anterior chamber and posterior chamber lens implants, based on data from 923 cases. The results have been more accurate than those from presently available theoretical formulas, and the well-known phenomenon of predicting too much dioptric power in eyes with short axial lengths has been avoided. Only 1% of the cases had a predicted lens power more than 3 diopters in error.

Cornea↗
PubMed1980

Slit-lamp fluorophotometry in intraocular lens patients.

Two hundred and sixty-four patients who had unilateral implant surgery and normal contralateral unoperated eyes were studied by slit-lamp anterior segment fluorophotomety. Patients tested five weeks to six months after surgeryb averaged 22% more fluorescein in the operated than in the unoperated eye, while those tested after six months averaged only 12% more fluorescein. Patients receiving topical indomethacin demonstrated an 11% increase in fluorescein, while those taking a placebo averaged a 33% increase. Patients with cystoid macular edema averaged a 46% increase in fluorescein compared with a 17% increase in the other patients. Twenty-seven control patients with unilaterally aphakic eyes and normal contralateral unoperated eyes, tested on an average of two years after surgery, showed essentially no increase in fluorescein in the operated eye. Fluorophotometry may be a valuable clinical tool in testing the effect of drugs on the blood-aqueous barrier and to screen patients for cystoid macular edema.

Aqueous Humor↗
PubMed1979

Dextran 40-containing infusion fluids and corneal swelling: a specular microscopic study.

We studied the effect of dextran 40 on corneal swelling with a specular microscope. The corneas were stressed by the addition of 10(-5)M ouabain to the infusion fluids for various time intervals. Dextran 40 inhibited swelling of functionally impaired corneas. However, when the dextran 40 was removed from the solution, the corneas swelled rapidly to reach the level of those incubated in ouabain without dextran 40. When the corneas were stressed in ouabain for a short period, dextran 40 had a protective effect that lasted even after its removal from the solution.

Animals↗
PubMed1979

Dextran's effects on stressed lenses: water, electrolyte, and radioisotope studies.

To evaluate the beneficial effects of dextran 40 as an additive to infusion solutions, we studied an experimental model of lens stress with use of buffered, low calcium (Ca++)-containing solutions. Incubation in low Ca++ solutions (pCa = 10.7) for ten hours (stress period) resulted in lens swelling and electrolyte imbalances that were irreversible even with reincubation in physiologic, normal Ca++-containing media (pCa = 2.7) (recovery period). The addition of 6% or more of dextran to the media inhibited lens water gain during the stress period. It also rendered the resultant electrolyte imbalances reversible during the recovery period, thus exerting a protective effect. Radioisotope-tracer studies showed that dextran improved the ability of the lens to accumulate rubidium chloride Rb 86 and reduced its efflux during both the stress and recovery periods. Although dextran did not markedly decrease sodium chloride Na 22 uptake by lenses under stress, it did allow the lens to remove the 22Na during the recovery period.

Animals↗
PubMed1979

300 primary anterior chamber lens implantations: gonioscopic findings and specular microscopy.

A total of 300 consecutive quadruped anterior chamber intraocular lenses were implanted. Gonioscopy was performed in all cases and prospective specular microscopy was performed in the last 97 cases. Iris tucking of at least one lens foot was noted in 28% of the cases. Tucking occurred less often (20% of the cases) when the lens length was 13 mm, increasing with lens lengths longer and shorter than 13 mm. Slight lens rotation was noted in 8% of the cases. Blood vessels (rarely appearing to be neovascular) were noted around an implant foot or in the anterior chamber angle near a lens foot in 30% of the cases. A statistically significant difference in endothelial cell loss was noted between the Choyce lens (18.6%) and the Tennant lens (12.4%).

Anterior Chamber↗
PubMed1979

The Medallion suture lens: management of complications.

In a study of 613 Medallion suture implant patients, 87% of the 613 and 96% of those under 70 years of age had a postoperative visual acuity of 20/40 or better. The most common operative complication was corneal endothelial trauma, which was graded and correlated with endothelial microscopy; however, only 0.5% of cases had permanent corneal opacification. Cystoid macular edema occurred in 32 cases (5.2%), and 56% (18) of these patients regained 20/40 vision or better. Implant loop subluxation occurred in 19 cases (3.1%), but this incidence should decrease by increasing implant loop tip-to-tip distance. The data presented put in perspective the relative importance of the various complications encountered, with primary emphasis on the management of these complications.

Astigmatism↗
PubMed1979

Total cataract extraction through a 3-mm incision: a report of 650 cases.

We treated 650 consecutive cases of phacoemulsification with total capsulectomy. More than 91% of cases had best corrected visual acuities of 20/40 or better. In those with vision of 20/100 or less (3.5%) no cause for decreased acuity could be related to the surgery; 94% of cases had less than 1.5 diopters of residual astigmatism. Vitreous loss, occurring in 2.9% of cases, could be related to initial inexperience and errors in technique rather than patient age. Postoperative complications included transient striate keratitis (2.3%), persistent corneal edema (one case), cystoid macular edema (2.8%), and aphakic retinal detachments (2.6%). There were no hyphemas, flat or shallow anterior chambers, or filtering blebs postoperatively. We believe that this technique of total cataract extraction through a 3-mm incision yields the same results as an intracapsular extraction, but with less complications, and all the benefits of a small limbal incision.

Adult↗
PubMed1978

Four hundred consecutive pars plana vitrectomies with the vitrophage.

We performed 400 consecutive pars plana vitrectomies, using the vitrophage. Most patients (68%) showed some degree of visual improvement; only 8% had a decline in visual acuity postoperatively. The major operative complications were controllable bleeding from iris vessels and intravitreal stalks (19%) and retinal tears (2%). No retinal dialysis was noted. The major, early postoperative complications were related to corneal decompensation in 38% of the cases; this persisted beyond two weeks in only 7%. Increased intraocular pressure occurred in 19% and postoperative rubeosis iridis developed in 10% of the diabetic patients. Complications related to rebleeding occurred in 18% of the diabetic patients within the first two weeks, and an additional 9% had late rebleeding. Less frequent complications included one case of endophthalmitis, late retinal detachment in 5%, and phthisis bulbi in 2% of all cases. All complications were considerably more frequent and severe in the diabetic population.

Anesthesia, Local↗
PubMed1978

Biometric analysis of intraocular lens power required to produce emmetropia: results of 450 implants.

We analyzed 450 consecutive cases of intraocular lens implantation (omitting only two inadvertent implantations in patients with high myopia) to determine the dioptric lens power in each case required to produce emmetropia. The mean was 18.3 D with a standard deviation of 2.6 D. The data did not conform to a normal or Gaussian distribution because of an abnormally high number of cases that required greater than 25 D to achieve emmetropia and clustering between 17 to 19 D. The deviation from a normal distribution may be explained by our considering patients with high hyperopia and high myopia (which are for the most part excluded from intraocular lens data) to be separate populations. The data are valuable to the intraocular lens surgeons, in that they demonstrate the range and frequency of intraocular lens powers needed to achieve emmetropia in a large population sample.

Aphakia↗
PubMed1978

Endothelial cell loss and trauma during intraocular lens implantation: a specular microscopic study.

We analyzed the results of a retrospective specular microscopic study of 80 cases with unilateral medallion suture implants and contralateral unoperated eyes. In all cases a clinical estimation of operative endothelial trauma (ET), graded from 0 to 3+, was made at the time of surgery. The mean decrease in endothelial cell density (compared to the unoperated eye) for those 33 patients with ET 0 was 19%. There was a direct correlation between ET and decrease in endothelial cell density up to a mean of 59% for those 18 patients graded ET 2.5 to 3.0. The role of sample bias and small case sampling is significant in explaining the large discrepancy in endothelial cell loss after intraocular lens implantation reported in the literature.

Cell Count↗
PubMed1978

Pars plana vitrectomy in the management of pupillary block glaucoma following irrigation and aspiration.

Pupillary block glaucoma developed in 3 children treated with irrigation and aspiration using the Cavitron phacoemulsification system. One had a congenital cataract, 1 had blunt trauma, and 1 had a penetrating injury. The factors contributing to pupillary block included excessive retained lens material, severe post-traumatic inflammation with synechia formation in 2 cases, and the lack of iridectomy in a case requiring a membrane discission. The pupillary block was successfully treated by pars plana vitrectomy in all cases; however, vision in 1 eye was lost owing to secondary glaucoma resulting from delay in treatment and the development of 360 degrees peripheral anterior synechiae.

Biopsy, Needle↗
PubMed1978

Determination of intraocular lens power: a comparison with and without ultrasound.

Two consecutive and sequential series of 100 pseudophakic patients were compared. In the first series intraocular lens power was determined by clinical means. In the second series axial length, using an easily operated commercially available A-scan unit, keratometry, and estimation of anterior chamber depth data were entered into an electronic calculator programmed to determine intraocular lens power. In the first series 47% of patients had a residual refractive error of 1 diopter or less, whereas 72% were within this range in the second series. With clinical lens power determination, there were three cases of residual deviation from emmetropia of more than 4 diopters; there was none greater than 3 diopters in the group using the A-scan. Lens power determination is more accurate using ultrasonography and the presently available instrumentation can be incorporated easily into a busy private practice.

Humans↗
PubMed1977

Vitrophage in management of congenital cataracts.

We have used the vitrophage for combined lensectomy and vitrectomy in six eyes with congenital cataracts. No intraoperative complications were encountered. One week after operation four of the six eyes had clear corneas, and all eyes showed a bright red reflex. With follow-up ranging from 18 to 21 months all eyes had clear corneas and a view of the posterior pole consistent with 20/20 vision.

Adolescent↗