Biomedical subjects

Virender S Sangwan

Publications and source records attributed to Virender S Sangwan.

At least 19 recordsLinked to original sources

PubMed2007

Role of amniotic membrane graft for ocular chemical and thermal injuries.

PURPOSE: To evaluate the results of amniotic membrane transplantation (AMT) for ocular surface reconstruction in chemical and thermal injuries. METHODS: Retrospective review of case records of patients who had undergone AMT for chemical injuries (January 1998 to May 2001). RESULTS: Seventy two eyes of 69 patients were studied of which 24 were acute cases (median-2 days, range, 1-20 days) and 48 were chronic cases (median-12.4 months, range, 1.02-95.8 months). Mean age was 22.4 years (SD +/- 13.34 years) and average follow up duration was 7.8 months (SD +/- 7.1). Main clinical findings were symblephara (52.8%), corneal vascularization (51.3%), conjunctivalization (45.8%), Limbal ischemia (45.8%), Limbal stem cell deficiency (55.5%) and epithelial defect (48.6%). 18 cases were due to acid injuries (5 acute, 13 chronic), 52 were due to alkali (18 acute and 34 chronic) and 2 cases were due to thermal burns (1 each acute and chronic). Overall success rate was 87.5% in acute cases and 72.9% in chronic cases. Indication-wise success rates were 94.3% for epithelial defect healing, 88.2% for symptomatic relief, 59.7% for ocular surface reconstruction, and 55% for improving limbal stem cell function. Success was not achieved in any outcome measure in 1/24 (4.2%) in acute group and 6/48 (12.5%) in chronic group. CONCLUSION: AMT helps in ocular surface reconstruction, promotes rapid epithelial healing and partially restores limbal stem cell function. It can be considered as an effective modality for the ocular surface restoration in chemical and thermal injuries in selected cases. Success rates in acute and chronic cases are comparable.

Acute Disease↗

PubMed2006

Cataract extraction outcomes in patients with Fuchs' heterochromic cyclitis.

PURPOSE: To analyze the visual outcomes and complication rate after cataract extraction and posterior chamber intraocular lens (PC IOL) implantation in patients with Fuchs' heterochromic cyclitis. SETTING: L.V. Prasad Eye Institute, Hyderabad, India. METHODS: This retrospective nonrandomized interventional study comprised 103 patients who were examined at the uvea clinic at L.V. Prasad Eye Institute between March 2000 and March 2004 and who were diagnosed with Fuchs' heterochromic cyclitis and cataract. They had extracapsular cataract extraction or phacoemulsification with IOL implantation. Outcomes measures were postoperative visual acuity, ocular inflammation, and complication rate. RESULTS: There were 57 men and 54 women in the study; the mean age was 31.36 years +/- 11.55 (SD) (range 10 to 60 years). Postoperative best corrected visual acuity (BCVA) at 5 weeks was 20/40 or greater in 91 patients (88.3%) (95% confidence interval [CI], 82.1-94.5). Eight patients (7.8%) had vitreous inflammation 5 weeks postoperatively. Five patients (4.9%) preoperatively and 3 patients (2.9%) postoperatively had elevated intraocular pressure. Clinically detected cystoid macular edema developed in 1 patient. The mean follow-up was 12.9 months in 53 patients. At the final follow-up, 49 of 53 patients (91.5%) (95% CI, 99.0-84.0) had a visual acuity of 20/40 or greater. Ten eyes (18.9%) had mild anterior chamber reaction. Decreased visual acuity (20/40 or worse) was the result of anterior chamber reaction in 4 patients, glaucoma in 3 patients, vitreous inflammation in 2 patients, and posterior capsule opacification, corneal edema, macular hole, and astigmatism in 1 patient each. CONCLUSIONS: Cataract surgery with PC IOL implantation in patients with Fuchs' heterochromic cyclitis resulted in good visual outcomes. Postoperative inflammation was mild and developed in few cases.

Adolescent↗

PubMed2006

Spontaneneous hydrops in pellucid marginal degeneration: documentation by OCT-III.

Corneal pellucid marginal degeneration (PMCD) is an idiopathic condition characterized by non-inflammatory, non-ulcerative thinning of inferior peripheral cornea. PMCD has been reported occasionally complicated with hydrops owing to break in descemet membrane. We herein report a 38-year-old man, who presented with sudden dimness of vision in right eye. Clinical findings and Orbscan II were suggestive of PMCD in both eyes with hydrops in right eye. Slit-lamp and optical coherence tomography of right eye showed central descemet's detachment without any break. Patient underwent descemetopexy by isoexpansile C3F8 (14%) and is doing well with significant improvement in the hydrops.

Adult↗

PubMed2006

Pseudoepitheliomatous hyperplasia mimicking ocular surface squamous neoplasia following cultivated limbal epithelium transplantation.

A 12-year-old girl with total limbal stem cell deficiency in the right eye following chemical burns underwent autologous cultivated limbal epithelium transplantation from the healthy left eye. Postoperatively at 6 weeks a mass at the limbus was noted, which increased in size and involved infero-nasal limbus extending over 5 mm on bulbar conjunctiva. It was a gelatinous, placoid freely movable mass with irregular surface, multiple intralesional cysts without feeder vessels or intrinsic vascularization and stained brilliantly with rose bengal. Histopathology following excision biopsy showed hyperplastic epithelium with stratified columnar cells and goblet cells. At the last follow-up, 6 months following cultivated limbal epithelium transplantation the ocular surface was stable without any recurrence of the lesion. We herein report a rare complication of epithelial hyperplasia presenting as leukoplakia following cultivated limbal epithelium transplantation mimicking ocular surface squamous neoplasia.

Carcinoma, Squamous Cell↗

PubMed2006

Clinical outcome of autologous cultivated limbal epithelium transplantation.

PURPOSE: To report the clinical outcome of autologous cultivated limbal epithelial transplantation. METHODS: Eighty-six patients' records and their clinical photographs were reviewed for demographics, primary etiology, type of limbal transplantation, ocular surface stability, visual acuity, final outcome and possible factors affecting outcome and complications. RESULTS: Eighty-eight eyes of 86 patients with limbal stem cell deficiency (LSCD) underwent autologous cultivated limbal epithelium transplantation between March 2001 and May 2003, with a mean follow-up of 18.3 months. The etiology of LSCD was alkali burns in 64% patients. Sixty-one eyes had total LSCD. Thirty-two of the 88 eyes had undergone amniotic membrane transplantation and 10 eyes had previously undergone limbal transplantation with unfavorable outcome. Nineteen eyes underwent penetrating keratoplasty, of which 11 grafts survived at the final follow-up. Finally, 57 eyes (73.1%, 95% CI: 63.3-82.9) had a successful outcome with a stable ocular surface without conjunctivalization, 21 eyes (26.9%, 95%CI: 17.1-36.7) were considered failures and 10 patients were lost to follow-up. CONCLUSION: LSCD can be successfully treated by autologous cultivated limbal epithelium transplantation in majority of the cases.

Adolescent↗

PubMed2006

Expansive mortar-induced ocular injury.

We describe here a case of bilateral chemical injury (with an expansive mortar which is being used in recent times to cut the rocks). On examination limbal ischemia was more in the left eye (9 clock hours) than the right eye (2 clock hours). The case was managed by bilateral removal of foreign bodies, along with conjunctival resection and amniotic membrane transplantation in the left eye. At six-month follow-up, patient had best corrected visual acuity of 20/30 and 20/60 in the right and left eyes respectively. Since this being an occupational hazard, proper eye protection gear should be used by persons using this expansive mortar.

Accidents, Occupational↗

PubMed2005

High-resolution genotyping of Pseudomonas aeruginosa strains linked to acute post cataract surgery endophthalmitis outbreaks in India.

BACKGROUND: Investigation of two independent outbreaks of post cataract surgery endophthalmitis identified the reservoir of epidemic strains of P. aeruginosa. METHODS: Patient isolates cultured from vitreous fluid of all the nine cases and from the peripheral devices of phacoemulsification machine were subjected to high-resolution Fluorescent Amplified Fragment Length Polymorphism (FAFLP) analysis. RESULTS: FAFLP based genotyping of the isolates confirmed nosocomial transmission. Although biochemical characterization and antibiotic susceptibility profiles grouped all the isolates together, FAFLP based genotyping revealed that, all the outbreak isolates were derived from 2 different strains, with independent origins. One group of isolates was traced to phacoprobe and the second one to the internal tubing system of the phacoemulsification machine used in cataract surgery. In silico analysis indicated possible evolution in both the clusters of P. aeruginosa isolates due to genetic polymorphisms. The polymorphisms were mapped to gene products (cell envelope, outer membrane proteins) possibly having significant role in pathogenesis. CONCLUSION: The present study is probably the first one to apply FAFLP typing successfully to investigate outbreaks of postoperative endophthalmitis (POE) in an ophthalmic setting, which was able to identify the source, and helped to make rational decisions on sterilization procedures that halted more cases of infection in these hospitals.

Acute Disease↗

PubMed2005

Early results of penetrating keratoplasty after cultivated limbal epithelium transplantation.

OBJECTIVE: To describe the early results of penetrating keratoplasty (PKP) in patients who had previously undergone cultivated limbal epithelium transplantation. METHODS: Medical records of patients with limbal stem cell deficiency due to chemical burns who underwent PKP after cultivated limbal epithelium transplantation were reviewed for demographics, primary etiology, type of limbal transplantation, ocular surface stability, visual acuity, graft clarity, and complications. Histopathologic features of the recipient corneal buttons were studied with special attention to epithelial status. RESULTS: Of the 125 patients with limbal stem cell deficiency treated with cultivated limbal epithelium transplantation, 15 underwent PKP at a mean interval of 7 months (range, 2-12 months) following cultivated limbal epithelium transplantation (autologous, n = 11; allogenic, n = 4). All 4 patients treated with allogenic cultivated limbal epithelium transplantation were undergoing immunosuppressive therapy. Fourteen (93%) of the 15 eyes had a successful corneal graft with a stable corneal epithelium. Preoperative best-corrected visual acuity was less than 20/200 in 14 of the 15 eyes. At a mean +/- SD follow-up of 8.3 +/- 5.0 months after PKP, the best-corrected visual acuity was more than 20/60 in 8 eyes, 20/200 to 20/60 in 5 eyes, and less than 20/200 in 2 eyes. Three of the 15 eyes experienced corneal allograft rejection, which was managed successfully. One eye with graft rejection also had glaucoma. None of the limbal epithelial allografts showed signs of rejection. CONCLUSIONS: Early results of PKP following cultivated limbal epithelium transplantation are favorable when performed after stabilizing the ocular surface. Adequate immunosuppression is essential for allogenic cultivated limbal epithelium transplantation to avoid rejection. Corneal allografts can separately reject the limbal allografts.

Adolescent↗

PubMed2005

Acute corneal hydrops treated by intracameral injection of perfluoropropane (C3F8) gas.

PURPOSE: To report a case of acute hydrops with intrastromal cleft in a patient of keratoconus with associated Marfan's syndrome, treated with intracameral injection of perfluoropropane (C(3)F(8)) gas. DESIGN: Interventional case report. METHODS: A nonexpansile concentration of perfluoropropane gas (0.2 ml) was injected intracamerally in the operating room under aseptic precautions. RESULTS: There was complete and rapid resolution of corneal edema. CONCLUSION: Intracameral perfluoropropane gas in nonexpansile concentration may be a useful modality for treatment of corneal edema in acute corneal hydrops.

Acute Disease↗

PubMed2005

Cataract surgery in patients with Mooren's ulcer.

PURPOSE: To assess the outcome of cataract surgery in patients with Mooren's ulcer. SETTING: Ocular Immunology and Uveitis Service, L.V. Prasad Eye Institute, Hyderabad, India. METHODS: In this interventional case series, the medical records of 6 patients with Mooren's ulcer who had cataract surgery were retrospectively reviewed. Five patients had uneventful extracapsular cataract extraction with intraocular lens (IOL) implantation, and 1 patient had phacoemulsification with IOL implantation. The visual acuity and postoperative course of the patients were reviewed. The patients were followed to detect, and if present treat, a recurrence of Mooren's ulcer. RESULTS: The follow-up ranged from 3 months to 2 years. The preoperative visual acuity ranged from 20/60 to hand movements. Postoperatively, the best corrected visual acuity improved to 20/20 to counting fingers close to face. Mooren's ulcer recurred 8 months after surgery in 1 patient and was treated appropriately. CONCLUSIONS: Results indicate that cataract surgery can be safe in patients with Mooren's ulcer and visually significant cataract. Performing surgery in a quiet, noninflamed eye improves the prognosis in these cases.

Adult↗

PubMed2005

Cataract surgery in Stevens-Johnson syndrome.

Cataract surgery can be safely performed in patients with Stevens-Johnson syndrome (SJS) with visually significant cataracts. Maintaining ocular surface integrity improves the prognosis of cataract surgery in this high-risk population. We present the outcome of cataract surgery in a retrospective chart review of 3 eyes in 2 patients with SJS. Uneventful extracapsular cataract extraction with intraocular lens implantation was performed. Follow-up ranged from 3 to 24 months. The visual acuity and ocular surface integrity were reviewed. The preoperative visual acuity was counting fingers at 1 meter in all 3 eyes. The best corrected visual acuity (BCVA) improved to 20/40 in 2 eyes and 20/50 in 1 eye postoperatively. A drop in BCVA ranging from 20/100 to 20/200 was noted during follow-up.

Cataract Extraction↗

PubMed2005

Eosinophil activation in Wegener's granulomatosis: a harbinger of disease progression?

PURPOSE: To investigate the relation between eosinophil activation in tissue from patients with an active, limited form of Wegener's granulomatosis (WG) affecting the eye and subsequent systemic disease activity. METHODS: Analysis of ocular specimens obtained from 10 patients was performed. Sections were probed with antibodies to assess the presence of major basic protein (MBP) and eosinophil cationic protein (ECP). RESULTS: Four of the 10 specimens demonstrated the presence of MBP and ECP. WG progressed to the complete form in two of these patients, who received no or inadequate treatment. The other two, treated with cyclophosphamide for one year, did not progress to the complete form of WG during observation after therapy. CONCLUSIONS: Activated eosinophils in sclera or conjunctiva of patients with ocular limited WG may predict progression to complete WG.

Adult↗

PubMed2005

Amniotic membrane transplantation for ocular surface reconstruction.

The amniotic membrane, composed of 3 layers, the epithelium, basement membrane, and the stroma, was first used along with the chorion as a biologic membrane to promote healing of skin burns in 1910. In ophthalmology, it was used in 1940 in the management of conjunctival defects. Its revival in the 1990s was due to its ability to reduce ocular surface inflammation and scarring, promote rapid epithelialization due to the presence of growth factors, and antimicrobial properties. This has resulted in its application in several ocular disorders. A review of the literature shows that amniotic membrane is definitely beneficial in some but not all pathology. The future of amniotic membrane transplantation is very exciting, especially in the field of limbal stem cell research. However, further work is needed to elucidate whether it functions merely as a biologic contact lens or whether it has additional benefits.

Amnion↗

PubMed2005

Cultivated corneal epithelial transplantation for severe ocular surface disease in vernal keratoconjunctivitis.

PURPOSE: To report cultivated epithelial transplantation in 2 patients with vernal keratoconjunctivitis (VKC) with severe ocular surface disease. METHODS: Two patients initially diagnosed with burnt-out VKC presented with bilateral photophobia, decreased vision, and corneal neovascularization. The first patient underwent living-related conjunctival-limbal allograft in the left eye and cultivated limbal epithelial cell allotransplant in the right. The second patient underwent unsuccessful amniotic membrane transplantation (AMT) followed by autologous cultivated limbal epithelial cell transplantation in the worse eye. RESULTS: Both patients had onset of VKC in the first decade. Surgical intervention in both led to marked amelioration in symptoms and improvement in vision. In patient 1, vision improved from 20/800 (both eyes) to 20/30 in the right and 20/100 in the left eye at a follow-up of 34 months. In patient 2, it improved from 20/400 to 20/50 after the second procedure, 25 months postoperatively. Histopathology of the excised pannus revealed fibrosis and mononuclear cell infiltrates in all 3 eyes. CONCLUSIONS: Severe ocular surface disease may occur in persistent VKC, leading to marked visual loss. AMT alone may be insufficient to restore the ocular surface, and limbal epithelial cell transplantation is warranted.

Adolescent↗

PubMed2005

Outcome of corneal transplant rejection: a 10-year study.

PURPOSE: To study the incidence of graft rejection and the predictive factors for its reversibility. METHODS: It is a retrospective study of 1927 consecutive penetrating keratoplasties performed between January 1990 and January 2000 with more than 6 months follow up. A total of 224 rejection episodes were noted in 183 patients. Of these, 184 first rejection episodes were included in this study. RESULTS: The incidence of first rejection episode was 9.55%. Of patients 87% were symptomatic during the episode with vision loss being the commonest. The average time of onset of rejection was 15.25 +/- 14.4 months (median 11.7 months). In total, 53.3% of rejections occurred within 1 year after surgery. Of the patients who completed minimum 3 months follow up after the rejection episode, the rate of reversibility was 63.3%. Major predictive factors for a poor outcome after rejection were repeated grafting and associated anterior vitrectomy during surgery. The reversibility of the episode did not differ significantly with the modality of treatment used, but treatment with intravenous steroids within 7 days of onset of rejection may have a role in reducing the recurrences of rejection episodes, thus increasing the graft survival. CONCLUSION: Regrafts and associated anterior vitrectomy were significant risk factors for a poor outcome following rejection episode.

Adolescent↗

PubMed2005

Early results of penetrating keratoplasty following limbal stem cell transplantation.

PURPOSE: To describe the early results of penetrating keratoplasty (PKP) in patients who had earlier received limbal transplantation (LT). METHODS: Prospective, non-comparative interventional case series comprising of four patients with limbal stem cell deficiency (LSCD) due to chemical injury (Cases 1, 2, 4) and xeroderma pigmentosum (Case 3). Cadaveric kerato-limbal allografts or living-related conjunctival-limbal allografts were done in four eyes followed by PKP for visual rehabilitation 3-4.5 months later. The following details were noted: demographics, primary aetiology, type of limbal transplant (cadaveric or living-related), immunosuppression, vision and ocular surface stability before and after LT and PKP, surgical complications and outcome of PKP. RESULTS: Three eyes received living-related conjunctival-limbal allotransplantation and one received cadaveric kerato-limbal allograft. Duration of follow up after PKP ranged from 4 to 11 months. Visual acuity improved in the early postoperative period in all patients but reduced in 2 due to endothelial rejection and after trans-scleral cyclophotocoagulation for medically uncontrolled glaucoma. The ocular surface remained stable in all patients. All patients were started on immunosuppression on the first postoperative day. This was continued till the last follow-up visit. Post-PKP complications were punctate epithelial keratopathy, corneal allograft rejection and secondary glaucoma (one patient each). CONCLUSION: Satisfactory visual rehabilitation is possible after PKP following LT without compromising ocular surface stability. However, a prolonged and close follow-up is warranted to avert complications.

Adult↗

PubMed2004

Ophthalmic applications of preserved human amniotic membrane: a review of current indications.

Preserved human amniotic membrane (AM) is currently being used for a wide spectrum of ocular surface disorders. The AM has a basement membrane, which promotes epithelial cell migration and adhesion. The presence of a unique avascular stromal matrix reduces inflammation, neovascularization and fibrosis. The basic tenets of amniotic membrane transplantation (AMT) are to promote re-epithelialization, to reconstruct the ocular surface and to provide symptomatic relief from surface aberrations. AMT is a useful technique for reconstruction of surface defects resulting from removal of surface tumors and symblephara. AMT has effectively restored a stable corneal epithelium in eyes with, persistent epithelial defects and corneal ulcers. In the setting of acute ocular burns and SJS, AMT has satisfactorily reduced scarring and inflammation. AMT alone may be an effective alternative for partial limbal stem cell deficiency. However remarkable improvements in surface stability have resulted from concurrent AMT and limbal stem cell transplantation, wherein the limbal grafts are obtained from the normal fellow eye, living relative or cadaveric eye. In severe or bilateral cases, well being of the donor eye is a major concern. Currently, the most unique application of preserved human AM in ophthalmology is its use as a substrate for ex-vivo expansion of corneal and conjunctival epithelium. In this novel technique of tissue engineering, epithelial stem cells can be safely harvested and expanded on denuded AM. The resultant composite cultured tissue has been successfully transplanted to restore vision, as well as the structure and function of damaged ocular surfaces.

Amnion↗

PubMed2004

Limbal stem cell transplantation.

The past two decades have witnessed remarkable progress in limbal stem cell transplantation. In addition to harvesting stem cells from a cadaver or a live related donor, it is now possible to cultivate limbal stem cells in vitro and then transplant them onto the recipient bed. A clear understanding of the basic disease pathology and a correct assessment of the extent of stem cell deficiency are essential. A holistic approach towards management of limbal stem cell deficiency is needed. This also includes management of the underlying systemic disease, ocular adnexal pathology and dry eye. Conjunctival limbal autografts from the healthy contralateral eye are performed for unilateral cases. In bilateral cases, tissue may be harvested from a cadaver or a living related donor; prolonged immunosuppression is needed to avoid allograft rejection in such cases. This review describes the surgical techniques, postoperative treatment regimes (including immunosuppression for allografts), the complications and their management. The short and long-term outcomes of the various modalities reported in the literature are also described.

Clinical Trials as Topic↗