Biomedical subjects

D S Rootman

Publications and source records attributed to D S Rootman.

At least 55 records · Page 3Linked to original sources

PubMed1994

Epikeratophakia for correction of complicated aphakia.

We reviewed the cases of 21 patients (22 eyes) who underwent epikeratophakia for aphakia with at least 4 months' follow-up. Thirteen had traumatic cataracts, six had relative contraindications for implantation of an intraocular lens (IOL), one had a dislocated IOL and one had bilateral congenital cataracts. The mean best corrected visual acuity was 20/32.0 (range 20/20 to 20/70) before surgery and 20/38.6 (range 20/20 to 20/70) after surgery. The uncorrected visual acuity improved in all eyes. Twenty eyes (91%) were within two lines of the preoperative best corrected acuity; all eyes were within four lines. Twenty eyes were within 3.0 dioptres of emmetropia postoperatively; all eyes were within 5.0 dioptres of emmetropia. No serious complications were encountered. We conclude that epikeratophakia is a good alternative for the correction of aphakia.

Adolescent↗

PubMed1993

Malignant acanthosis nigricans. A case report.

PURPOSE: The authors present a case of malignant acanthosis nigricans that has two unusual aspects. The first is involvement of the lid margins with confluent papillomata, causing severe visual impairment, and the second is the association with lung malignancy. METHODS: A 65-year-old Portuguese man presented with decreased vision, papillomatous lid lesions, pruritus, and progressive thickening of the skin of his face, neck, axillae, and inguinal creases. A diagnosis of acanthosis nigricans was made after skin biopsy. Systemic investigations showed a suprahilar mass, and biopsy was positive for squamous cell carcinoma of the lung. RESULTS: The patient underwent excision of papillomata from all four lid margins, and this was repeated 1 year later. He also completed a course of palliative radiotherapy. CONCLUSION: Malignant acanthosis nigricans is rarely associated with lung neoplasms, being more commonly a manifestation of intra-abdominal malignancies. Of note in this case is the extensive ocular involvement and visual impairment.

Acanthosis Nigricans↗

PubMed1993

Continuous flow perfusion of gentamicin with a scleral shell reduces bacterial colony counts in experimental Pseudomonas keratitis.

We have previously shown the pharmacokinetic value of delivering gentamicin to the rabbit anterior segment using the Morgan Therapeutic Lens. The present study utilized an intrastromal injection model of Pseudomonas keratitis to test the therapeutic efficacy of continuous flow delivery of gentamicin with the Morgan therapeutic lens. All eyes (n = 52) received an intrastromal injection of approximately 1800 colony forming units (CFU) of Pseudomonas aeruginosa. At 22 hours after injection, eyes were perfused for 6 hours with saline or gentamicin (1, 2.5 or 5 mg/ml), or received gentamicin drops (13.6 mg/ml) at 15 minutes for four doses, then hourly for 6 hours. Corneas were homogenized and plated to determine bacterial survival, and expressed as log colonies (CFU). Log CFU recovered were 7.37 +/- 0.04, 6.64 +/- 0.20, 5.64 +/- 0.31, and 3.56 +/- 0.50 log CFU for saline perfusion, 1, 2.5, 5 mg/ml gentamicin perfusion respectively. Following six hours of treatment with topical fortified gentamicin drops, 5.93 +/- 0.34 log CFU were recovered. Gentamicin perfusion (5 mg/ml) was significantly different from saline or the other treatment groups (P < 0.05). Continuous corneal perfusion with the Morgan Therapeutic Lens demonstrated an increasing dose response curve with increasing perfusate concentration. It was effective in the treatment of experimental Pseudomonas keratitis.

Animals↗

PubMed1993

Continuous epidermal growth factor delivery in corneal epithelial wound healing.

PURPOSE: To investigate the effects of a single prolonged exposure to recombinant epidermal growth factor on the healing of anterior keratotomy wounds in New Zealand white rabbits. METHODS: After wounding, eyes were perfused for 1, 2, 4, and 8 hours with either epidermal growth factor solution at a concentration of 50 micrograms/ml or balanced saline solution using a Morgan therapeutic lens (Mortan Inc, Missoula MT) and a syringe pump. Furthermore, concentration response was evaluated by perfusing with epidermal growth factor solutions at concentrations of 5, 50, 100 and 500 micrograms/ml for 4 hours. Wound healing rates were determined by quantitative morphometry of the wound area. The ratio of healing rates of eyes perfused with epidermal growth factor and control eyes provided a measure of the effect of epidermal growth factor on wound healing, and was defined as the epidermal growth factor enhancement factor. RESULTS: The enhancement factor was found to be 1.04 +/- 0.08, 1.17 +/- 0.07, 1.43 +/- 0.09, and 1.59 +/- 0.07 for perfusion times of 1, 2, 4, and 8 hours, respectively. The concentration response enhancement factors were 0.99 +/- 0.08, 1.43 +/- 0.09, 1.21 +/- 0.09, and 0.95 +/- 0.07 for the 5, 50, 100, and 500 micrograms/ml 4-hour perfusions, respectively. CONCLUSION: The results indicated that continuous epidermal growth factor exposures of as few as 2 hours produced a significant increase in healing rates (P < 0.05); increasing the time of exposure further increases the rate of wound healing. Results from the concentration response experiments showed that the optimum epidermal growth factor concentration for enhancing epithelial wound healing is approximately 50 micrograms/ml.

Animals↗

PubMed1992

Continuous flow contact lens delivery of gentamicin to rabbit cornea and aqueous humor.

The Morgan Therapeutic Lens (MTL) was investigated as a continuous corneal perfusion system in New Zealand white rabbits. Gentamicin concentration in the cornea and aqueous humor delivered by the MTL was compared to gentamicin drops (13.6 mg/ml) administered every 15 or 30 minutes. Gentamicin (1 mg/ml) or 5 mg/ml was perfused at 10 ml/hr for up to 4.0 hours. At each time interval of 0.5, 1, 2 and 4 hours, homogenized corneas and aqueous humour were assayed for gentamicin concentrations. The highest aqueous humour gentamicin concentrations of 57.99 +/- 12.86 micrograms/ml were significantly higher with the MTL and 5 mg/ml of gentamicin compared with the MTL and 1 mg/ml of gentamicin or than drops applied every 30 minutes, but not significantly different than drops every 15 minutes. Highest corneal concentrations of gentamicin of 496.04 +/- 101.16 micrograms/gm cornea were significantly higher with MTL and 5 mg/ml of gentamicin compared with the MTL and 1 mg/ml gentamicin or than drops applied every 30 minutes, but not significantly different than drops every 15 minutes. All mean gentamicin concentrations attained via the MTL exceeded the mean inhibitory concentration for most sensitive bacterial species. The MTL is a reliable drug delivery system with distinct advantages, and may be a useful therapeutic modality in the ocular delivery of gentamicin and other drugs.

Animals↗

PubMed1992

Eyelid and fornix reconstruction in bilateral abortive cryptophthalmos (Fraser syndrome).

Cryptophthalmos refers to a group of uncommon congenital anomalies of eyelid formation that can occur alone or in combination with multiple congenital anomalies as part of the Fraser syndrome. We present a case of bilateral abortive cryptophthalmos in a child with Fraser syndrome and discuss the problems of surgical management. A brief discussion of isolated and syndromic cryptophthalmos, including normal eyelid development, the pathogenesis of cryptophthalmos, and the management options follows.

Abnormalities, Multiple↗

PubMed1992

Familial congenital corneal anaesthesia.

Congenital corneal anaesthesia is a cause of severe corneal ulceration and scarring in childhood. Although uncommon, it may be underdiagnosed when present as an isolated entity. Measures such as the use of elbow splints and tarsorrhaphy may be necessary to prevent visual loss. In rare instances, the condition may be inherited. A family is presented with autosomal dominant isolated congenital corneal anaesthesia, and the systemic associations and treatment of the condition are reviewed.

Adult↗

PubMed1992

Toxicity and pharmacokinetics of intravitreally injected ciprofloxacin in rabbit eyes.

To assess the toxicity of intraocular injection of ciprofloxacin, 22 New Zealand white rabbits received midvitreal injections of 100, 200, 400, 800 or 3200 micrograms of ciprofloxacin in 0.1 mL of distilled water (39 eyes) or 0.1 mL of distilled water only (5 eyes). The ocular pharmacokinetics of intravitreally injected ciprofloxacin was determined by aqueous humour and vitreous sampling 1, 2, 4, 8, 12, 18 or 24 hours after midvitreal injection of 100 micrograms of the drug in one eye each of 25 New Zealand white rabbits. The samples were analysed by means of a disc diffusion bioassay. No ocular damage was noted on ophthalmoscopy at any of the concentrations tested. Histologic study showed mild, transient vacuolation of the nerve-fibre layer in all eyes, including the control eyes, 2 hours after injection; at 24 hours no vacuolation was evident except at concentrations of 800 and 3200 micrograms, at which plexiform layer damage was evident. Peak aqueous and vitreous levels of ciprofloxacin were obtained at 1 hour (0.59 and 27.26 micrograms/mL respectively); the vitreous level fell to below 1.0 micrograms/mL 12 hours after injection. We conclude that intravitreally injected ciprofloxacin may be a safe and useful antibiotic in the treatment of aminoglycoside-resistant bacterial endophthalmitis.

Animals↗

PubMed1992

Collagen shields: efficacy, safety and comfort in the treatment of human traumatic corneal abrasion and effect on vision in healthy eyes.

To study the efficacy, safety and comfort of porcine collagen shields in the treatment of traumatic corneal abrasion, patients with corneal abrasions that had occurred within 24 hours before examination were treated with either a collagen shield (18 patients) or tight patching (12 patients). There was no significant difference in the rate of healing or the proportion of corneas healed between the two groups. The collagen shield was significantly more comfortable than the patch (p < 0.05). After 1 hour of wear the collagen shield allowed useful vision (mean 20/100) in nine healthy volunteer subjects. Collagen shields may be of benefit in carefully selected cases of traumatic corneal abrasion.

Adolescent↗

PubMed1992

Cyclosporine in the treatment of nonmicrobial inflammatory ophthalmic disease.

Eighteen patients with severe, progressive nonmicrobial inflammatory ophthalmic disease (including five with intermediate uveitis, four with sympathetic ophthalmia and three with serpiginous choroiditis) that had not responded to conventional therapy were treated with cyclosporine. Three of the four patients with sympathetic ophthalmia responded quickly and maximally, and the fourth showed partial improvement. One patient, with several corneal graft failures in the right eye, started cyclosporine therapy after undergoing left corneal transplantation; at the last follow-up visit the graft had been clear for almost 3 years. The response was inconsistent in patients with other types of eye disease. In general, the drug was well tolerated; however, two patients stopped treatment because of unpleasant side effects. No serious or irreversible complications developed. The results suggest that cyclosporine therapy is useful in the treatment of sympathetic ophthalmia and in high-risk corneal transplantation.

Adolescent↗

PubMed1991

Corneal transplantation in infants, children and young adults: experience of the Toronto Hospital for Sick Children, 1979-88.

Between 1979 and 1988, 85 penetrating keratoplasty procedures were performed in 54 patients aged 1 month to 18.2 years at the Hospital for Sick Children, Toronto. The minimum length of follow-up was 3 months. A clear transplant was obtained in 27 eyes: 7 of 16 eyes with Peter's anomaly, 0 of 8 eyes with congenital glaucoma, 2 of 5 eyes with herpes simplex keratitis, 6 of 8 eyes with corneal dystrophy and 12 of 17 eyes with traumatic corneal scars. The most recent visual acuity was best in the trauma and dystrophy groups and worst in the congenital glaucoma group. Visual acuity results were better in older children and were fair in younger children and those with postoperative complications. Although penetrating keratoplasty is more difficult in children than in adults, it has a reasonable chance of success. However, the poor outcome in the congenital glaucoma group indicates that the procedure is not warranted in such patients.

Adolescent↗

PubMed1991

Further evaluation of collagen shields as a delivery system for 5-fluorouracil: histopathological observations.

Collagen shields are a potential delivery system for antifibroblast drugs such as 5-fluorouracil after filtration surgery. To determine whether collagen shields produce histologic evidence of inflammation when implanted subconjunctivally, shields were implanted into four rabbit eyes and six guinea pig eyes and retained for 7 or 14 days. Two rabbit eyes and two guinea pig eyes served as controls. Seven days after implantation in the rabbit eyes foreign-body giant cells were present at the surface of the shield, and early deposition of connective tissue was evident around the shield. The inflammatory response at 14 days was similar but more intense. In the guinea pig eyes the collagen shields induced substantially less inflammation, and there was marked shield degradation at 14 days. The results suggest that the inflammatory response in rabbits may be species specific and that collagen shields may be of value as a drug-delivery system for antifibroblast drugs in other species.

Animals↗

PubMed1990

Reactivation of HSV-1 in primates by transcorneal iontophoresis of adrenergic agents.

Transcorneal iontophoresis of adrenergic agents has been shown to reactivate latent herpes simplex virus type 1 (HSV-1) and to produce viral shedding in the tear film in rabbits and mice, but not, to date, in nonhuman primates. In this study, we demonstrated induced reactivation of latent HSV-1, viral shedding, and production of ocular lesions in nine squirrel monkeys (Saimiri sciureus) by iontophoresis of 6-hydroxydopamine (6-HD) with topical instillation of epinephrine or with iontophoresis of timolol. Monkey corneas were scarified and inoculated with McKrae strain HSV-1 on three separate occasions. All monkeys received daily intramuscular prednisolone for 39 or 46 days prior to ionotophoresis. Once latency was established, a single ionotphoresis of 6-HD was performed on both eyes in five of the monkeys, followed by 1% epinephrine given topically four times daily for 5 days. Iontophoresis of timolol was performed on both eyes in the other four monkeys once per day on 3 consecutive days. Eight of the ten eyes receiving 6-HD and epinephrine shed HSV-1; seven eyes developed deep punctate, dendritic, or geographic corneal lesions. Seven of the eight eyes receiving timolol shed HSV-1; six of the eyes developed lesions suggestive of HSV-1 specific corneal lesions. The methods used in this report were slightly different from those used to reactivate HSV-1 in rabbits, in that repeated inoculations with HSV-1 and repeated intramuscular injections with prednisolone were required; however, these results demonstrate that iontophoresis of adrenergic agents can produce shedding and recurrent epithelial lesions in the nonhuman primate.

Animals↗

PubMed1990

Potential value of collagen shields as a subconjunctival depot release system.

Collagen shields are fabricated from dissoluable porcine scleral tissue and have been used as an ocular drug delivery system. The aim of the present study was to determine the time and extent of shield absorption when implanted subconjunctivally, and the absorption and release of 5-fluorouracil in vitro. Thirty New Zealand white rabbit eyes were employed. BioCor 72 hour collagen shields were surgically implanted in the subconjunctival space. Rabbits were sacrificed at 7, 14 and 21 days after shield implantation, and the remaining shields removed. Remaining shields were measured by both dry weight and protein assay. The absorption and release of 5-FU from collagen shields was determined in vitro using tritiated 5-FU. The collagen shields were not fully absorbed for at least 14 days in the subconjunctival space. In vitro, 5-FU absorbed by the shields reached saturation levels at approximately 15 minutes. Nearly 100% of the 5-FU was released within 15 minutes. Although the time for subconjunctival shield absorption may be useful for antifibroblast drugs, the rate of 5-FU release from these shields is not optimal for enhancing bleb formation when shields are soaked in solutions of 5-FU.

Absorption↗

PubMed1990

Acanthamoeba keratitis with two species of Acanthamoeba.

We describe a case of Acanthamoeba keratitis related to soft contact lens wear. The patient presented with a 3-week history of severe uniocular pain, radial stromal infiltrates and subepithelial infiltrates with no epithelial defect. Acanthamoeba was cultured from the corneal biopsy specimen, contact lens and lens case. The corneal biopsy culture grew both A. castellani and A. polyphaga as well as Escherichia coli. The patient was treated with topical dibromopropamidine isethionate (Brolene) drops, neomycin and polymyxin B drops and fortified gentamicin drops. Gradual clinical improvement ensued.

Acanthamoeba↗

PubMed1989

Tobramycin iontophoresis into corneas infected with drug-resistant Pseudomonas aeruginosa.

Iontophoretic application of tobramycin was used to deliver drug to the cornea of rabbit eyes infected with a tobramycin-resistant strain of Pseudomonas aeruginosa (MIC = 31.25 micrograms/ml). Corneas infected with P. aeruginosa 27853/pMG6 were treated 22 hours after infection with tobramycin delivered by either iontophoresis, mock iontophoresis (eye cup without current), or application of fortified topical drops. Corneal iontophoresis of tobramycin at 25 mg/ml caused more than a three log reduction in bacteria; yielding a significantly lower number of bacteria compared to untreated controls and all other treatments (P less than or equal to 0.0001). Corneal iontophoresis of tobramycin at 10 mg/ml showed a one log reduction in the number of bacteria per cornea, yielding a significantly lower number of bacteria compared to untreated controls (P less than or equal to 0.0001), corneas treated with nine topical applications of 1.36% tobramycin drops (P less than or equal to 0.0001), and corneas treated with mock iontophoresis (P less than or equal to 0.02). These results suggest that iontophoresis is a powerful ocular delivery system for tobramycin and may be suitable for use with other chemotherapeutic agents.

Administration, Topical↗

PubMed1989

Trifluridine decreases ocular HSV-1 recovery, but not herpetic lesions after timolol iontophoresis.

To determine the effect of a topically applied antiviral agent on shedding of herpes simplex virus type 1 (HSV-1) into the tear film and corneal epithelial lesions, ten rabbits latently infected with HSV-1 were subjected to transcorneal iontophoresis of 0.01% timolol once a day for 3 consecutive days to induce viral shedding and lesions. Iontophoretic induction was performed similarly in five uninfected rabbits as controls. Half of the infected rabbits and all of the uninfected controls received topical 1.0% trifluridine five time a day for 9 days, beginning the day after the first iontophoresis. All eyes were examined daily for 10 days by slit-lamp biomicroscopy and tear film samples collected on swabs were analyzed for virus. In the infected rabbits, the eyes treated with trifluridine had significantly fewer swabs positive for HSV-1 than the untreated eyes (P less than 0.001); however, there was no significant difference in the numbers of lesions in the treated and untreated eyes. The uninfected controls had no positive swabs and developed no lesions. These results suggest that topical treatment with trifluridine may reduce recovery of HSV-1 from the tear film, but does not affect the incidence of iontophoretically induced corneal epithelial lesions.

Animals↗

PubMed1989

Canaliculitis caused by Mycobacterium chelonae after lacrimal intubation with silicone tubes.

Two and a half weeks after a 62-year-old man underwent bilateral nasolacrimal intubation with silicone tubes, canaliculitis and conjunctivitis developed. Cultures yielded Mycobacterium chelonae sensitive to amikacin. Successful therapy required removal of the tubes followed by intensive intravenous and topical chemotherapy. This is, to our knowledge, the first report of mycobacterial infection as a complication of lacrimal intubation.

Amikacin↗