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PubMed2006

Deep lamellar keratoplasty by intracorneal dissection: a prospective clinical and confocal microscopic study.

OBJECTIVE: To evaluate the clinical findings, visual outcomes, and confocal microscopic corneal features of a surgical technique for manual deep lamellar keratoplasty (DLKP) with intentional sparing of the most posterior stroma. DESIGN: Noncomparative, prospective, 12-month interventional study. PARTICIPANTS: Forty-six eyes of 45 patients who had corneal pathologic features without endothelial abnormalities and requiring corneal graft were treated by DLKP by manual stromal delamination. They were examined clinically after surgery and using in vivo confocal microscopy at 2 weeks and 1, 3, 6, and 12 months. INTERVENTION: The surgical technique consisted of an intracorneal deep manual stromal dissection through a 4-mm limbal incision at 50 mum from Descemet's membrane (DM). After trephination, an endothelial free graft was sutured. MAIN OUTCOME MEASURES: Topographic parameters, interface depth and reflectivity, and anterior and postinterface keratocyte density; visual acuity was correlated with these parameters. RESULTS: Two eyes had rupture of the DM. Two eyes that had delayed epithelial healing because of graft override with stromal inflammation underwent a second surgery (penetrating keratoplasty). Mean uncorrected logarithm of the minimum angle of resolution (logMAR) uncorrected visual acuity and logMAR best-corrected visual acuity (BCVA) improved from preoperative values (1.342+/-0.239 and 0.923+/-0.226, respectively) to 0.421+/-0.122 and 0.104+/-0.068, respectively, at 12 months. Mean topographic astigmatism was 3.09+/-1.30 diopters (D) at 3 months after suture adjustment, and 2.87+/-0.92 D at 12 months after suture removal. Average interface depth was 64.2+/-6.7 microm at 15 days and showed no significant changes up to 12 months. Mean interface reflectivity was highest at 15 days (95.5+/-15.7 light reflectance units [LRU]) and showed a progressive decrease over time of 55.3+/-8.7 LRU at 12 months. A significant negative correlation was observed between BCVA and topographic astigmatism up to 1 month and between BCVA and interface reflectivity starting from 6 months after surgery. CONCLUSIONS: Deep lamellar keratoplasty by intracorneal dissection provides visual and clinical results comparable with that of other DLKP techniques. Visual recovery is slow and progressive, taking up to 1 year. Confocal microscopy enables precise evaluation of corneal features, interface morphologic features, and reflectivity, demonstrating a negative correlation between interface reflectivity and BCVA showing that the progressive recovery over months of the interface transparency is correlated with the increase in visual acuity after 6 months.

Adolescent↗
PubMed2006

Graft reepithelialization after penetrating keratoplasty using organ-cultured donor tissue.

OBJECTIVE: To analyze graft reepithelialization after penetrating keratoplasty using organ-cultured donor tissue. DESIGN: Retrospective observational cohort study. PARTICIPANTS: One thousand one hundred thirty-eight consecutive penetrating keratoplasties (1003 patients) performed between 1992 and 2004 were analyzed, and 1003 were included (1 graft per patient was included). METHODS: Slit-lamp examination after fluorescein staining. MAIN OUTCOME MEASURE: Graft reepithelialization time was recorded. RESULTS: The average graft reepithelialization time was 4.6+/-13.2 days (range, 1-210 days; median, 2.5 days). Complete corneal epithelial healing was obtained in 1 day in 28.5% of patients, in 3 days in 65.8%, in 7 days in 93.6%, and in 14 days in 97.0%. Postoperative chronic epithelial defects occurred in 3.0% of patients. In univariate analysis, death-to-storage time, storage time, deswelling time, rejection risk, trephination size, suture method, use of dexamethasone ointment during surgery, use of sodium hyaluronate during surgery, and use of high postoperative steroid regimen significantly influenced the graft reepithelialization time (P<0.05). In multiple regression, only the rejection risk (beta = 0.07; P = 0.045), use of sodium hyaluronate at the end of surgery (beta = -0.17; P = 0.001), and steroid regimen (beta = 0.09; P = 0.022) significantly influenced the graft reepithelialization time. CONCLUSIONS: The use of sodium hyaluronate at the end of surgery to coat the ocular surface shortened graft reepithelialization time after penetrating keratoplasty using organ-cultured donor tissue. Graft reepithelialization time was longer in high-risk recipients, and it increased with high dexamethasone eyedrops regimen.

Aged↗
PubMed2005

The influence of alendronate on bone formation after autogenous free bone grafting in rats.

OBJECTIVE: This study was undertaken to investigate the influence of alendronate on bone formation after autogenous free bone grafting in rats. STUDY DESIGN: Fifty-six male Wistar-Albino rats were divided into 3 groups: baseline, saline-treated, and alendronate-treated groups, and followed up at 2, 4, and 12 weeks. In the femur of the rats, autogenous free bone grafts 3 mm in diameter and 2 mm in length were harvested with a standard trephine bur. The bone defects 3 mm in diameter and 2 mm in length were created 5 mm from the donor sites. Each graft was placed in the bone defect and stabilized by perifemoral wiring. The alendronate-treated rats were administered 0.25 mg/kg alendronate subcutaneously daily. The saline-treated rats were given daily saline solution. Serum calcium, phosphate, parathyroid hormone, 1,25-dihydroxyvitamin D, bone alkaline phosphatase (BAP), osteocalcin, and urine calcium were measured. The changes in the number of osteoblasts bordering active bone formation surface and osteoid and lamellar bone formation were evaluated to measure anabolic bone activity. RESULTS: Alendronate caused significant increase in serum osteocalcin and BAP levels biochemically and the number of osteoblasts histopathologically. CONCLUSION: Alendronate may be considered among therapeutic options to improve bone formation process in different bone remodeling cases. Further detailed studies should be focused on dosage- and time-dependent effects of alendronate on bone formation.

Alendronate↗
PubMedDate not supplied

[Minimally invasive surgery for treating of complicated fronto-ethmoidal sinusitis].

OBJECTIVES: Functional endoscopic sinus surgery (FESS) is nowadays the "gold standard" for frontal sinus pathologies, but management of acute situations and the aproach and/or the extent of the surgery perfomed in the frontal recess remains controversial nowadays. MATERIAL AND METHODS: We report our experience in 4 patients with orbital celulitis due to frontal sinusitis who underwent combined external surgery (mini-trephination) and endoscopic sinus surgery. RESULTS: All patients managed sinus patency without any complications. CONCLUSIONS: We found this combined sinusotomy as an easy, effective and reproductible technique in order to resolve the difficult surgical management of complicated frontal sinusitis.

Adolescent↗
PubMed2001

Tectonic sclerokeratoplasty and tectonic penetrating keratoplasty as treatment for perforated or predescemetal corneal ulcers.

PURPOSE: To report the clinical outcome of patients with perforated or predescemetal corneal ulcers treated by tectonic, centric or eccentric penetrating keratoplasty or by tectonic sclerokeratoplasty. DESIGN: Nonrandomized clinical trial. METHODS: The study included 60 patients (60 eyes) with perforated or predescemetal corneal ulcers who were consecutively operated on by the same surgeon. Fifty-two patients underwent tectonic penetrating centric or eccentric keratoplasty. Eight patients with paralimbal corneal ulcers underwent tectonic sclerokeratoplasty. A control group consisted of 76 patients (76 eyes) electively undergoing central penetrating keratoplasty for treatment of inactive central corneal scars. RESULTS: In the study group with perforated or predescemetal corneal ulcers, best-corrected postoperative visual acuity ranged from perception of light to 0.80 (median, 0.10), with 54 of 60 eyes (90%) attaining an improvement of best visual acuity. In 10 of 60 patients (16.7%), tectonic penetrating keratoplasty had to be re-performed because of a recurring corneal ulcer. Patients with sclerokeratoplasty and patients with eccentric keratoplasty did not differ in clinical outcome, despite larger trephine and corneal lesion size in the sclerokeratoplasty group. Among study patients compared with control patients, postoperative visual acuity was significantly lower (P =.01), postoperative refractive and keratometric astigmatism were significantly higher (P <.05), and immunologic graft reactions (P =.02) and suture loosening (P <.001) occurred significantly more often. CONCLUSIONS: Eyes with perforated corneal ulcers or predescemetal corneal ulcers can usually be saved by tectonic keratoplasty or sclerokeratoplasty, with a moderate to considerable amount of remaining useful vision. In case of doubt, one may prefer conservative treatment of corneal ulcers and to electively perform central keratoplasty when the ulcers have healed. For selected clinical situations, sclerokeratoplasty is an alternative to keratoplasty for surgical treatment of paralimbal corneal defects.

Adolescent↗
PubMed2002

Vitreoretinal morphology of plasmin-treated human eyes.

PURPOSE: To investigate the ultrastructure of the vitreoretinal interface following an intravitreal injection of plasmin. METHODS: Plasmin (2 U/0.1 ml) was injected into the vitreous cavity of five postmortem human eyes. The five fellow eyes received phosphate-buffered saline and served as controls. After incubation at 37 degrees C for 30 minutes, the globes were placed in fixative and hemisected. Specimens for scanning and transmission electron microscopy were obtained using a corneal trephine. RESULTS: All plasmin-treated eyes showed complete vitreoretinal separation with sparse collagen fibrils covering the inner limiting membrane. All control eyes showed an attached cortical vitreous. At the vitreous base, there was no cleaving effect. The retinal morphology of plasmin-treated eyes was unchanged. CONCLUSIONS: Plasmin induces a cleavage between the vitreous cortex and the inner limiting membrane without morphologic alteration of the retina.

Aged↗
PubMed2002

A novel technique for harvesting keratolimbal allografts from corneoscleral buttons.

PURPOSE: To describe a method for obtaining partial-thickness keratolimbal allografts from corneoscleral buttons to be used in corneal limbal stem cell transplantation. DESIGN: Description of device design and technique for use. METHODS: Cyanoacrylate tissue adhesive, placed on the posterior side of a trephinated corneoscleral rim, is used to secure the allograft to a disposable acrylic sphere that is attached to a cylindrical base. RESULTS: After fixation of the corneoscleral rim to the acrylic sphere, keratolimbal allograft harvesting is performed as a continuous strip dissection with a 65 Beaver blade. This technique minimizes trauma to the epithelial stem cells, provides excellent stability of the corneoscleral rim during harvesting, and preserves the central corneal button. CONCLUSIONS: This method for obtaining keratolimbal allografts effectively provides tissue stabilization during harvesting, minimizing epithelial stem cell trauma and eliminating the need for whole donor globes.

Corneal Transplantation↗
PubMed1996

Annular keratotomy for the treatment of painful bullous keratopathy.

PURPOSE: To determine whether annular keratotomy can relieve pain associated with bullous keratopathy. METHODS: Three patients with painful bullous keratopathy and poor visual potential underwent partial-thickness (0.30 to 0.42 mm) trephination of the cornea under local anesthesia. RESULTS: All patients reported an absence of pain and foreign body sensation during an average follow-up interval of six months. The surgical procedure was uncomplicated; however, two eyes developed increased central corneal stromal edema. CONCLUSIONS: Annular keratotomy appears to be a relatively safe and simple surgical procedure that may be useful in managing pain in eyes with painful cornea edema and poor visual potential.

Aged↗
PubMed1996

Retinal pigment epithelial cell count, distribution, and correlations in normal human eyes.

PURPOSE: To determine the number of the retinal pigment epithelial cells, their regional distribution, and correlations with general variables in normal human eyes. METHODS: We examined 53 normal human donor eyes from individuals with a mean age of 58.6 +/- 18.8 years and an axial length of less than 27 mm. After opening the globes by a 16-mm corneoscleral trephination, up to 25 biopsy specimens of the retina and retinal pigment epithelium were obtained in four meridians. The retinal pigment epithelial cells and the retinal photoreceptors were counted on photographs taken from the apical retinal pigment epithelial surface and the inner photoreceptor segments. RESULTS: Total number of the retinal pigment epithelial cells was 3,556,290 +/- 490,700 (mean +/- S.D.; range, 2,130,500 to 4,653,200), and it was positively correlated with the number of rods and cones, the total area of the retina, the optic disk size, and the retinal pigment epithelial cell density but was independent of gender. The retinal pigment epithelial cell density decreased significantly (P < .001) from the fovea (4,220 +/- 727 cells/mm2) to the midperiphery (3,002 +/- 460 cells/mm2) and to the outer peripheral fundus regions (1,600 +/- 411 cells/mm2). In the retinal periphery, the retinal pigment epithelial cell density was the highest (P < .01) in the nasal fundus region compared with any other fundus quadrant. The retinal pigment epithelial cell density decreased by about 0.3% per year with increasing age. CONCLUSIONS: These data on the quantitative anatomy of the retinal pigment epithelium may be important for physiology and pathophysiology of the visual process, especially in evaluating the effects of aging.

Adolescent↗
PubMed1994

Excimer laser ablation rate and corneal hydration.

During excimer laser photorefractive keratectomy, dehydration of the cornea begins as soon as the epithelium is removed. Corneal hydration might affect the excimer laser ablation rate, which could affect the accuracy of correction. We studied the effect of corneal hydration on the excimer laser ablation rate in bovine eyes. To control hydration, bovine corneoscleral rims were equilibrated in dextran solutions of varying concentrations. One button trephined from each rim underwent laser ablation. Hydrated tissue ablation rates (amount of collagen, ground substance, and water removed per pulse) and dry component ablation rates (amount of collagen and ground substance removed per pulse) were calculated from mass removed. The hydrated tissue ablation rate at physiologic hydration was 0.40 micron/pulse. As corneal hydration increased, the hydrated tissue ablation rate increased by 5.6 micrograms/cm2/pulse per increase in unit corneal hydration (simple linear regression analysis, P = .0001). The dry component ablation rate decreased linearly by 0.82 microgram/cm2/pulse per unit increase in corneal hydration (simple linear regression analysis, P = .0001). Both clinical data and theoretical arguments imply that dry component ablation rate determines refractive outcome after photorefractive keratectomy. Since the dry component ablation rate increases as the cornea dries, significant dehydration of the cornea before ablation might lead to relative overcorrections of myopia. Surgeons should use a technique that minimizes changes in hydration to maximize the predictability of excimer laser photorefractive keratectomy.

Animals↗
PubMed1980

Thermal wedge with penetrating keratoplasty to reduce high corneal cylinder.

I devised a new technique using a thermal wedge resection at the time of keratoplasty to reduce excessive amounts of corneal astigmatism. Surface cautery was used to draw this thermal wedge of corneal tissue into the area to be trephined, and removed at surgery from the patient's cornea. The final result was the same as combining a surgical tissue wedge resection with keratoplasty. This new technique has resulted in reduction of the astigmatic error by as much as 8.5 diopters.

Adult↗
PubMed1999

Linker for activation of T cells (LAT), a novel immunohistochemical marker for T cells, NK cells, mast cells, and megakaryocytes: evaluation in normal and pathological conditions.

LAT (linker for activation of T cells) is an integral membrane protein of 36-38 kd that plays an important role in T cell activation. Using a rabbit polyclonal antibody generated against the cytosolic portion of LAT, we investigated the immunohistochemical expression of LAT in normal and pathological hematolymphoid tissues. LAT reacts with human T cells in paraffin sections, including decalcified bone marrow trephines. LAT appears early in T cells at the thymocyte stage and before TdT expression in embryos, and is expressed in peripheral lymphoid tissues, without restriction to any T cell subpopulations. In addition to T cells, natural killer (NK) cells (evaluated with flow cytometry), megakaryocytes and mast cells are also LAT-positive, whereas B cells and other myeloid and monocytic derived cells are negative. Tested on a total of 264 paraffin-embedded tissue biopsies, LAT reacted with the great majority (96.8%) of T/NK-cell neoplasms, covering the full range of T cell maturation. Although antibodies to both LAT and CD3 had a similarly high sensitivity in the staining of T/NK-cell lymphomas, when used in conjunction, they successfully identified a higher number of cases (98.4%). Atypical megakaryocytes from different hematological disorders, as well as mast cells in mastocytosis were also LAT-positive, but all neoplasms of B cell origin, Hodgkin's lymphomas, and several nonlymphoid malignancies were negative. These data indicate that the anti-LAT antibody may be of value to diagnostic histopathologists for the identification of T cell neoplasms.

Adaptor Proteins, Signal Transducing↗
PubMed1982

Biopsy of the spine using a needle with a rigid guide wire.

Biopsy of the spine is a potentially valuable investigation but suitable instruments and experience are difficult to obtain. The paper gives a detailed account of a trephine biopsy set which incorporates a rigid guide wire. Selection of cases, possible complications and difficulties encountered are described. The method used has proved safe; the proportion of successful biopsies depends on the nature of the cases selected for biopsy as well as the skill and experience of the operator.

Aged↗
PubMed1983

The diagnosis and staging of neuroblastoma.

Forty-five cases of neuroblastoma were reviewed to assess the value of current diagnostic methods. Urinary catecholamine and 3-methoxy-4-hydroxymandelic acid levels were elevated in only 48% and 60% of cases, respectively. All abdominal or pelvic tumour masses were detected by intravenous urography, ultrasound or computed tomography (CT): CT was the best single investigation but the two less expensive techniques detected most of the tumours. Trephine biopsy was more successful than aspiration in detecting bone marrow metastases. Liver scintigraphy was positive in six of seven cases with hepatic secondaries.

Abdominal Neoplasms↗
PubMed1995

Large optic discs in large eyes, small optic discs in small eyes.

The optic disc area, varying interindividually by a factor of 1:7, is correlated with the count of the retinal ganglion cell axons and photoreceptors. This study evaluated whether the variations in the disc size are additionally correlated with those of the coronary diameters of the globe. Fifty-three normal human donor eyes with a mean age of 54.2 +/- 19.6 years were included in the study. After performing a 16-mm corneoscleral trephination, the globes were fixed and the horizontal and vertical diameters of the globes were measured. We cut the globes into meridional slices sticking together at the posterior fundus region. The areas of the whole retina and the optic disc were planimetrically evaluated on photographs with a millimeter scale aligned. We found that the horizontal and vertical diameters of the globe were correlated with the optic disc size and the retinal surface area. Eyes with long horizontal and vertical diameters had a larger optic disc and a larger retinal surface area than eyes with short diameters. The results suggest the combination of large optic discs in large eyes and of small optic discs in small eyes. Taking into account the relatively low correlation coefficients of 0.3 and 0.4, the study also suggests the existence of other not-evaluated factors influencing the occurrence of large optic discs. The results go along with the reported association between a large optic disc area and a large cornea size.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

Effect of mitomycin C dissolved in reversible thermo-setting gel on the outcome of filtering surgery in the rabbit.

PURPOSE: Based on our previous report that showed enhanced transfer of mitomycin C to the sclera and the conjunctiva by dissolving the agent into a reversible thermo-setting gel, we conducted a study to investigate the efficacy of mitomycin C gel in the rabbit. METHODS: We subconjunctivally injected 0.1 mL of the mitomycin C gel solution containing several different amounts of the agent. Trephination was performed in the injected region 24 hours later. Intraocular pressure measurement, photography, and ultrasound biomicroscopic examination of the filtering bleb were conducted 1, 2, and 4 weeks postoperatively. RESULTS: The gel containing 3.0 microg or more mitomycin C significantly enhanced bleb formation and reduction in the intraocular pressure. CONCLUSIONS: The reversible thermo-setting gel seems to help the filtering bleb to survive in the rabbit and deserves further investigation as a new method of mitomycin C application.

Animals↗
PubMed2001

Benign lesions of the frontal sinus.

Benign tumors of the frontal sinus including fibro-osseous lesions and inverted papillomata present unique problems for the rhinologist. Because of the bony cavity surrounding the frontal sinus and relatively small portal into the nose, conventional techniques including the osteoplastic flap, frontal trephination, and lynch procedure have provided useful approaches to these tumors. The advent of endoscopic techniques in the management of chronic inflammatory disease of the paranasal and, specifically, frontal sinuses, has led to these traditional techniques being augmented successfully, and, in some cases, surpassed by newer endoscopic techniques. This article reviews the diagnosis and management of the two most common types of benign tumors of the frontal sinus, bony tumors and inverted papillomata, with emphasis on the usefulness of the endoscope in managing such lesions.

Adult↗
PubMed2006

[Total hip arthroplasty after failure of per- and subtrochanteric fracture fixation in elderly subjects].

PURPOSE OF THE STUDY: Most pertrochanteric fractures can be successfully fixed with osteosynthesis. Osteosynthesis fails however is a small number of patients who require re-operation for implantation of a total hip prosthesis. This situation occurs in particular when the material has penetrated the acetabulum and in elderly subjects. Although this type of arthroplasty is routine practice, few series have been reported. We present here outcome and complications of total hip arthroplasty after failure of per- and sub-trochanteric fracture fixation. MATERIAL AND METHODS: Between 1990 and 2000, twenty patients aged 79 years on average (range 62-78 years) underwent revision for total hip arthroplasty after failure of osteosynthesis for fracture of the upper femur. A gliding THS had been used for fixation in 18 patients, a plate in one and a Gamma nail in one. Osteosynthesis failure was related to early disassembly in ten patients, pseudarthrosis in eight and malunion in two. Revision was performed via a posterolateral approach in all cases. A standard total hip prosthesis was used in 16 patients, a longer femoral stem was required in four. Femoral components were cemented in 18 patients and non-cemented in two. The cup was a standard cemented cup in 12, retaining and cemented in eight. RESULTS: Mean operative time and blood loss were greater than in first-intention arthroplasties. All patients had lost their independence prior to the revision procedure. Despite their age, all recovered independence after a stay in rehabilitation. Most still required crutches. Use of a retaining cup enabled avoiding dislocation in all cases. For those who did not have a retaining cup, dislocation was the most frequent complication (3/12). The difficulties observed were: 1) elimination of associated infection before surgery; many of these elderly subjects had altered ESR and CRP values for various reasons; 2) abnormal position of the trochanteric mass because of a rotation defect; 3) malunion of the upper femur in the frontal or sagittal planes; 4) more or less easily achieved positioning of the femoral piece on the calcar; 5) difficult intraoperative identification of limb length due to loss of usual landmarks on the lesser and greater trochanter; 6) removal of fracture screws which sometimes required use of a trephine and bridging the last screw hole with a longer centromedullary stem. The most frequent postoperative orthopedic problems were leg length discrepancy (1-2 cm for eight patients), gluteus medius insufficiency, limping and pain at palpation of the trochanteric area. DISCUSSION: Despite the difficult technique and the potential complications which are more important than for first-intention arthroplasties, this series demonstrates that total hip prosthesis is a reliable solution for treating fixation failures of the upper femur.

Age Factors↗