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PubMed1996

[Temporary keratoprosthesis, vitrectomy and autokeratoplasty in endophthalmitis treatment].

Postsurgical endophthalmitis frequently requires emergency vitrectomy. Loss of corneal transparency can preclude vitreoretinal surgery. Due to the narrow time frame in which surgical treatment needs to be performed, donor corneas are often not available for grafting. In addition, the risk of primary graft failure is higher in eyes with acute endophthalmitis. Later regrafting after primary graft failure carries a higher risk of graft rejection. By a clinical case of endophthalmitis after cataract surgery, we demonstrate the surgical technique of combined pars plana vitrectomy, keratoprosthesis, and autokeratoplasty. Loss of corneal transparency precluded standard pars plana vitrectomy with fundus contact lenses. The cornea was trephined and replaced by a keratoprosthesis. The trephined cornea was stored in tissue culture medium and pars plana vitrectomy was performed. At the end of the procedure, the keratoprosthesis was removed and the patient's own cornea was re-implanted. The transparency of the cornea improved during the postoperative course, permitting slit-lamp biomicroscopy of the anterior segment.

Aged↗
PubMed2002

[New automated microkeratome for trepanation of lamellar keratoplasty].

BACKGROUND/PURPOSE: Lamellar keratoplasty is an established therapy of corneal pathologies without endothelial involvement and the lack of endothelial rejection is one of the major advantages compared to penetrating keratoplasty. The major disadvantages of manually prepared lamellar corneal grafts are the limited mechanical and optical quality but the automated lamellar therapeutic keratoplasty system ALTK (MORIA) is intended to overcome these disadvantages. The purpose of this preliminary work is to investigate histologically and in clinical cases, if the ALTK system can achieve this aim. PATIENTS AND METHODS: Corneas from two human donors were cut with a 300 microns trephine. After fixation, the stromal bed and the excised cup of one specimen were stained with PAS and examined by light microscopy and the other specimen was analyzed by scanning electron microscopy. In addition, follow-up data of two patients who received such a lamellar graft are reported for the first 9 and 7 months postoperation, respectively. RESULTS: The lamellar cut of homogeneous depth revealed only minor stromal trauma. Both clinical cases demonstrated only minimal interface haze during follow-up. Despite a remarkably clear cornea, visual acuity improved only slowly because the precise lamellar cut tended to partially reproduce any preexisting irregular astigmatism. CONCLUSIONS: The ALTK system simplifies and standardizes the trephination of lamellar corneal grafts but a longer follow up is necessary with respect to visual development and preservation of a clear graft.

Adult↗
PubMed1976

An artificial anterior chamber.

Corneas for penetrating keratoplasty that have been excised from the globe for storage ordinarily require punching of the donor tissue from the posterior surface. They may be trephined from the anterior surface when they are mounted on an instrument that forms a seal around the scleral rim of the excised cornea, allowing the endothelium to be supported physically by the liquid storage medium. The artificial anterior chamber protected the endothelial cells from damage as if they were still in the intact globe. The instrument allowed trephination to any desired depth and facilitated the cutting of corneal buttons with a rim of Descemet's membrane and endothelium. Sutures may be preplaced in the donor button before the button is seperated completely from the rest of the cornea. Iris prolapse did not interfere with the procedure.

Anterior Chamber↗
PubMed1989

Metabolic labeling of normal canine rod outer segment phospholipids in vivo and in vitro.

Twenty-four hours after the intravitreal injection of [3H]palmitate and [14C]docosahexaenoate in dogs, the rod outer segment phospholipids are highly labeled. Palmitate is found predominantly in phosphatidylcholine (PC), with lesser amounts in phosphatidylethanolamine (PE) and very little in either phosphatidylserine (PS) or phosphatidylinositol (PI). Docosahexaenoate most heavily labeled PE followed by PC, with lesser amounts in PS and very little in PI. Two-hour incubations of 3 mm trephine buttons removed from dog retinas produced very similar patterns of labeling with palmitate and docosahexaenoate. In vitro incubation of retina buttons with [3H]arachidonate produced heavy labeling of PI, with much less in PC and very little in either PS or PE. [3H]Glycerol labeled in PC, PI and PE in descending order but PS almost not at all. [3H]Serine labeled PS predominantly, but small amounts were found in PC, PE and PI. The trephine retina buttons can be utilized for multiple-precursor incubations and studies of differential metabolism in retinal regions, particularly when studying scarce tissue from mutant animals or humans with inherited retinal degenerations.

Animals↗
PubMed1989

Bone marrow examination in neuroblastoma patients: a morphologic, immunocytochemical, and immunohistochemical study.

Bone marrow examination was performed at the time of diagnosis, before initiation of therapy, and during follow-up of 14 consecutive patients with neuroblastoma who were treated at the National Hospital in Oslo. A total of 30 bone marrow specimens were examined by conventional histology, by immunohistochemistry with selected monoclonal antibodies to neuroblastoma cells (UJ 13A, UJ 167.11, PI 153/3, and A2B5) applied on trephines, and by morphologic evaluation of smears in addition to immunocytochemistry of aspirated bone marrow cells. The study confirmed the value of immunohistochemistry and immunocytochemistry for the detection of bone marrow involvement in neuroblastoma. Immunohistochemistry performed on bone marrow trephines was a slightly better adjunct than immunocytochemistry on aspirated bone marrow cells.

Adrenal Glands↗
PubMed2005

A technique to harvest Descemet's membrane with viable endothelial cells for selective transplantation.

PURPOSE: To describe a surgical technique using an artificial anterior chamber to facilitate harvest of Descemet's membrane (DM) and endothelium for corneal endothelial cell transplantation. DESIGN: Laboratory investigation. METHODS: Corneoscleral buttons of seven human donor eyes were mounted endothelial side up on an artificial anterior chamber. Keeping the endothelial side with its usual concavity, a manual trephination was made on the posterior surface with a 9.0-mm trephine, inside the Schwalbe line and just past the DM in depth. The chamber was filled with air, causing the endothelial side of the donor cornea to assume a convex configuration. The DM along with its endothelium was separated from the posterior stroma using a blunt cyclodialysis spatula. Drops of trypan blue 0.3% and alizarin red S 0.2% (n = 6) were applied. The stained DMs were examined under a light microscope and photographed to calculate the percentage of endothelial cell damage. Histology was done on the unstained cornea. RESULTS: The DM carrying endothelium was successfully removed from the posterior stroma in all seven eyes. Although the DM appears to be very friable, all samples were removed in toto without rupture. Vital staining showed a mean endothelial cell loss of 8.46% (standard deviation (SD) 6.9). Direct light microscopy demonstrated the preservation of endothelial cell morphology. CONCLUSIONS: This technique appears to be a safe and straightforward method to harvest DM for endothelial cell transplantation. Further studies are underway to determine the optimal method of insertion of the obtained healthy DM with endothelial cells through small corneal incisions.

Adolescent↗
PubMed2004

The cellular responses of articular cartilage to sharp and blunt trauma.

OBJECTIVE: To determine the response of immature articular cartilage to both sharp and blunt trauma in terms of cell death, cell proliferation and matrix synthesis. DESIGN: Blunt wounds were made with a trephine in full depth immature bovine articular cartilage explants which were cut in half through the center of the trephine wound with a sharp scalpel to produce blunt and sharp trauma on the same explant. Explants were maintained in culture for up to 10 days. Prior to fixation at days 2, 5 and 10, medium was supplemented with 10 microCi ml-1 35S-sulphate, [3H]-proline or [3H]-thymidine for 24h to assess matrix synthesis and cell proliferation. Cell death was assessed using a Live/Dead label. RESULTS: In the case of blunt wounds, a band of cell death was observed adjacent to the lesion edge. Microautoradiography demonstrated little radiolabel incorporation and, therefore, no new matrix synthesis or cell proliferation within this region. In contrast, wounds made with a sharp scalpel showed restricted cell death, with radiolabel incorporation adjacent to the lesion edge at all time points. This demonstrated not only chondrocyte proliferation and new matrix synthesis at the wound margin, but also an up-regulation of matrix synthesis adjacent to the lesion edge. CONCLUSIONS: In terms of clinical relevance, the use of sharp precise instruments during the surgical management of cartilage defects may be necessary to reduce cell death and promote matrix elaboration at the lesion edge in order to facilitate successful integration.

Animals↗
PubMed2006

Ambulatory in-office anterior iliac crest bone harvesting.

OBJECTIVE: A prospective study was performed to evaluate the harvesting of autologous bone within the private practice environment, using either a power-driven trephine or corticocancellous block harvesting, and to assess the clinical safety, postoperative morbidity, and patient satisfaction associated with this application. STUDY DESIGN: Thirty-nine patients requiring 40 bone harvests from the anterior iliac crest for maxillofacial reconstruction were included for study. The ages ranged from 16 to 73 years (mean 48.4 years). All surgeries were performed by a single surgeon. Patients were recovered and discharged home directly from the office. RESULTS: Forty iliac crest harvests were performed in the private practice venue from 2001 to 2004, 23 by motorized trephine and 17 by open corticocancellous block harvest. No peri-operative complications were encountered. Postoperative questionnaires were returned by 32 patients. Thirty patients reported that they would undergo hip surgery in an ambulatory environment again if required. CONCLUSION: Harvesting of bone from the anterior iliac crest is a safe and predictable surgical procedure for the private oral and maxillofacial surgical practice setting in selected cases, resulting in a low complication rate. Patient acceptance of this surgery in the private practice venue is high.

Adolescent↗
PubMed1998

A new surgical technique for deep lamellar keratoplasty with single running suture adjustment.

PURPOSE: To improve the technique of deep lamellar keratoplasty. METHODS: For the recipient eye, a divide-and-conquer technique was applied to deep lamellar keratoplasty. After trephinization, the recipient cornea within the trephine was divided into four quadrants to facilitate lamellar dissection at approximately 70% depth. This procedure of division was continued until the Descemet membrane was exposed in the central area. The corneal graft was placed with an adjusted single running suture. Seventeen eyes were treated with this technique. RESULTS: In 17 eyes of 15 patients, the mean visual acuity 6 months or more after deep lamellar keratoplasty was 20/52 with eyeglass correction and 20/80 without eyeglass correction. At 6 months or more after deep lamellar keratoplasty, the mean +/- SD keratometric astigmatism in 17 eyes was 3.2 +/- 2.3 diopters. CONCLUSION: This technique facilitates deep lamellar keratoplasty and prevents high or excessive astigmatism after surgery.

Astigmatism↗
PubMed1987

Comparison of collagen degradation and synthesis in the peripheral and central areas of experimental corneal grafts.

The distribution of collagen degradation and synthesis (turnover) between the central and peripheral areas of clear corneal allografts was determined, following transplantation of 6-mm [3H]proline-labelled corneal buttons from extensively pre-labelled, young rabbits into 13 nonradioactive mature rabbits. Control, contralateral 6-mm corneal buttons of each radioactive pair were frozen at -70 degrees C after being trephined into a central 3-mm button and a peripheral ring of cornea. The grafts were removed 10-100 days after the operation and trephined similarly to the paired controls. The central and peripheral areas of the graft and control corneal buttons were analysed separately for total hydroxyproline and radioactivity. A significant degradation of old collagen (as seen by the loss of total radioactivity) occurred early in both the central (19.4 +/- 6.1%) and peripheral (12.3 +/- 7.5%) areas of the grafted corneas, compared to the corresponding areas of the contralateral controls. A significant increase in new, non-radioactive collagen occurred in both the central (22.0 +/- 7.6%) and peripheral areas (30.6 +/- 6.1%); however, a significant net increase in total collagen occurred only in the peripheral area (18.3 +/- 11.4). Loss of original (old) collagen was significantly greater in the central area than in the peripheral area; whereas, the increase in new collagen was significantly greater in the peripheral area than the central area, accounting for a significant increase in total collagen. There was no correlation in collagen turnover with time after surgery. Collagen turnover occurs acutely throughout the clear corneal graft and thereafter is stable.

Animals↗
PubMed1990

Acute myeloid leukemia: immunohistologic findings in paraffin-embedded bone marrow biopsy specimens.

Immunohistochemical investigations were performed on decalcified, paraffin-embedded iliac crest trephine biopsy specimens from 30 cases of acute myeloid leukemia (AML, as defined by the FAB classification) with antibodies against B cells (L26, 4KB5, MB1, Ki-B3), T cells (UCHL1, MT1), myeloid/histiocytic cells (anti-neutrophil elastase, MAC387, anti-S-100 protein, anti-alpha 1-antichymotrypsin, DAKO-M1), natural killer/killer cells (anti-Leu-7), and megakaryocytes (anti-factor VIII-related antigen). (1) The blast cells of all the cases reacted with from at least two to at most eight different antibodies. Each antibody reacted with blast cells in a minimum of two (maximum 30) cases. (2) MT1, Ki-B3, anti-alpha 1-antichymotrypsin anti-neutrophil elastase, anti-S-100 protein, and MAC387 stained blast cells in more than 50% of the cases; MB1, L26, UCHL1, 4KB5, and DAKO-M1 in 20% to 50% of the cases; and anti-Leu-7 and anti-factor VIII-related antigen in less than 20% of the cases. (3) In the majority of cases many T lymphocytes, a small-to-moderate number of B lymphocytes, and a few Leu-7-positive lymphoid cells were intermingled with the blast cells. In some cases, especially where only a minor proportion of the blast cells was immunostained, it was nearly impossible to distinguish the lymphocytes of the tumor's stromal reaction from small blast cells. Thus, AML exhibits a heterogeneous immunophenotype in trephine biopsy specimens. Immunohistologic diagnosis of this disease in such specimens may be extremely difficult. Since staining of the blast cells with one or more of the antibodies generally used to define B cells, T cells, or their neoplastic derivatives is not uncommon, misinterpretation as non-Hodgkin's lymphoma of high-grade malignancy could easily occur. These findings also suggest that mixed-type (hybrid) acute leukemias with coexpression of myeloid and lymphoid cell markers could be more common than generally realized.

Adolescent↗
PubMed2003

Surgical technique of the supraorbital key-hole craniotomy.

BACKGROUND: The enormous development of microsurgical techniques and instrumentation together with preoperative planning using the excellent preoperative diagnostic facilities available, enables neurosurgeons to treat more complicated diseases through smaller and more specific approaches. METHODS: The technical details of the supraorbital key-hole craniotomy are described in this article as it has been evolving in our experience for more than 10 years. After an eyebrow skin incision with careful soft tissue dissection and single frontobasal burr-hole trephination, a supraorbital craniotomy is carried out with a diameter of about 1.5 x 2.5 cm. As a real frontolateral approach, the supraorbital craniotomy avoids removal of the orbital rim, the lesser sphenoid wing or the zygomatic arch. RESULTS AND CONCLUSIONS: The supraorbital craniotomy allows wide intracranial exposure of the deep-seated supra- and parasellar region, according to the concept of key-hole approaches. The limited craniotomy requires minimal brain retraction thus significantly decreasing approach-related morbidity. In addition, the short skin incision within the eyebrow, the careful soft tissue dissection, and the single burr hole trephination result in a pleasing cosmetic outcome.

Brain Diseases↗
PubMed2003

Impact of graft diameter on corneal power and the regularity of postkeratoplasty astigmatism before and after suture removal.

OBJECTIVE: To assess the impact of graft diameter on corneal curvature before and after removal of a double-running suture after nonmechanical penetrating keratoplasty (PK). DESIGN: Prospective, nonrandomized, comparative (self-controlled) single-center clinical trial. PATIENTS: Four hundred eighty-nine eyes with "two sutures in" and 308 eyes with "all sutures out" (mean age, 52+/-19 years) were included. The diagnoses were keratoconus (48%), Fuchs' and stromal dystrophies (31%), aphakic or pseudophakic bullous keratopathy (11%), and scars (10%). INTERVENTIONS: In all eyes, a central trephination was performed (donor trephination from the epithelial side) using the 193-nm Meditec excimer laser (Carl Zeiss Meditec, Jena, Germany) along metal masks with eight "orientation teeth/notches." Diameters were 8.0 mm, 7.5 mm, and 7.0 mm with a graft oversize of 0.1 mm. In 29% of eyes, additional cataract, intraocular lens surgery, or both were performed simultaneously. In all eyes, a double-running 10-0 nylon suture was applied. Zeiss keratometry and TMS-1 topography analysis were performed before removal of the first suture (14+/-4 months) and at least 6 weeks after removal of the second suture (20+/-4 months), but before any additional surgery, such as cataract extraction or refractive keratotomies. MAIN OUTCOME MEASURES: Topographic central corneal power (CP; keratometric diopters), keratometric astigmatism (KA), surface regularity index (SRI), and surface asymmetry index (SAI). The regularity of keratometry mires was recorded semiquantitatively from 0 = regular to 3 = not measurable (as published earlier). RESULTS: With both sutures in, median CP in 7.0-mm (42.0 diopters [D]; P = 0.04) and in 7.5-mm grafts (42.3 D; P = 0.007) was significantly lower than in 8.0-mm grafts (43.0 D). Keratometric astigmatism did not differ between groups (3.0 D vs. 3.0 D vs. 2.7 D). The SRI (1.66 vs. 1.43 vs. 1.11) and SAI (1.55 vs. 1.24 vs. 0.85) decreased significantly with increasing diameter. The proportion of regular keratometry mires (13% vs. 17% vs. 29%) increased, and the proportion of not measurable keratometries (45% vs. 18% vs. 9%) decreased with increasing diameter. With all sutures out, CP in 7.0-mm grafts (40.4 D) was significantly smaller than in 7.5-mm (43.6 D; P = 0.04) and 8.0-mm grafts (43.3 D; P = 0.04). Again, KA did not differ between groups (3.0 D vs. 3.2 D vs. 3.0 D). The SRI (1.40 vs. 1.09 vs. 0.84) and SAI (1.24 vs. 0.83 vs. 0.62) decreased significantly with increasing diameter. The proportion of regular keratometry mires (5% vs. 31% vs. 52%) increased, and the proportion of not measurable keratometries (42% vs. 11% vs. 4%) decreased with increasing diameter. CONCLUSIONS: After PK, a smaller graft diameter results in a flatter curvature and a higher degree of topographic irregularity, but not in higher net astigmatism. After suture removal, graft topography tends to regularize, whereas the principal differences between diameters do persist.

Adult↗
PubMed1995

Bilateral penetrating keratoplasty for keratoconus.

PURPOSE: To determine the effect of bilateral surgery on the rejection-free survival of penetrating keratoplasties (PK) performed for keratoconus. METHODS: The records of 587 patients with a PK for keratoconus who attended a single center over a 7-year period were reviewed. Details on 400 patients were sufficiently complete to permit a multivariate analysis of the factors suspected to influence graft survival. In 165 of these patients with bilateral grafts, the effect of a contralateral PK on graft survival was evaluated using actuarial methods. RESULTS: In first grafts for all patients, there was an increased rate of graft rejection with a host trephine greater than 7.50 mm in diameter and in patients with severe allergic eye disease (P < 0.01). In patients who had bilateral grafts, a graft to the contralateral eye increased the risk of rejection in the first eye to be grafted, and although this effect reduced with time, it was still present after an interval of up to 6 years between surgeries. A rejection episode in the first eye to be grafted increased the risk of rejection in the second eye (P < 0.001), but overall the second eye had a significantly lower risk of rejection when compared with either the first grafted eye or unilaterally grafted eyes (P < 0.001). The risk to the second grafted eye further reduced as the interval between the surgeries increased. CONCLUSIONS: In keratoconus, the diameter of the host trephine, severe allergic eye disease, and a graft surgery to the contralateral eye determine the risk of rejection in the index eye. The reasons the second grafted eye of patients receiving bilateral PKs appears to have an enhanced rejection-free survival are discussed.

Cornea↗
PubMed1996

Clinical and surgical factors influencing corneal graft survival, visual acuity, and astigmatism. Corneal Transplant Follow-up Study Collaborators.

PURPOSE: To quantify clinical and operative factors that influence corneal graft outcome. METHODS: A multifactorial analysis was done on 2242 corneal grafts registered by the United Kingdom Transplant Service from July 1987 to June 1991. RESULTS: There was an increased risk of graft failure in patients with preoperative diffuse and other noncentral stromal edema, less-common eye diseases, small trephine size, difference in donor and recipient sizes greater than 0.25 mm, and use of mixed continuous and interrupted sutures. Visual acuity 3 months after surgery was poorer in patients who had glaucoma and low visual acuity preoperatively, small trephine size, and combined vitreous surgery. Use of interrupted sutures resulted in higher astigmatism at 3 months. CONCLUSIONS: After allowing for the effects of recipient factors, surgical factors significantly affected corneal graft outcome. No factors that showed significant benefits for graft survival also adversely affected visual performance. Details of medical history, clinical condition, and surgical method failed to predict more than a small proportion of observed variability in visual performance of functioning grafts.

Astigmatism↗
PubMed1988

Follow-up studies with sequential bone marrow biopsies in chronic myeloid leukaemia and so-called primary (idiopathic) osteo-myelofibrosis. Evolution of histopathological lesions and clinical course in 40 patients.

A clinicopathological follow-up study was performed on 17 patients with chronic myeloid leukaemia (CML) and 23 cases with so-called primary (idiopathic) osteo-/myelofibrosis (OMF) concentrating on a comparison between clinical data and multiple sequential biopsies of the bone marrow. Histological classification of bone marrow lesions was done according to the subtypes proposed by Georgii et al. At clinical diagnosis initial trephine biopsies in CML showed in only 6/17 cases a pronounced granulocytic proliferation or CGL. In 9/23 patients with OMF a so-called hyperplastic or early hypercellular stage was encountered with a mixed megakaryocytic-granulocytic pattern without or with minimal reticulin fibres (CMGM/EMS). The histopathology of this early stage OMF as well as the later evolving advanced fibrosclerotic lesions (AMS/OMS) were by morphological aspects alone not distinguishable from cases with CML showing prominent fibrosclerotic alterations. At presentation 5/17 patients with CML displayed already some degree of reticulin fibre formation (EMS). Following serial trephine biopsies in CML with an increased megakaryocyte proliferation (CMGM), a remarkable tendency for myelofibrosis was present. The dynamics of this fibrosclerotic transformation seem to be variable in CML and OMF likewise. However, they are related to abnormal megakaryopoiesis as well as to duration respectively progress of disease, paralleled by corresponding haematological parameters. This longitudinal case control study emphasizes that histopathology of the bone marrow taken at clinical diagnosis may reflect different stages of chronic myeloproliferative diseases and therefore should be always accompanied by relevant clinical and cytogenetic findings to enable a correct diagnosis.

Adult↗
PubMed2004

[A serious complication of sternal puncture: penetrating injury of the ascending thoracic aorta].

INTRODUCTION: Penetrating thoracic aorta wounds are rare but responsible for a high mortality when medical and surgical management is delayed. OBSERVATION: We report the case of a 71 year-old patient with malignant lymphoma who sustained an accidental penetrating injury of the ascending thoracic aorta while undergoing trephine biopsy of the sternum. He was successfully treated with emergency sternotomy and aortic suture-repair. CONCLUSION: This case report highlights the limits of sternal trephine biopsy, notably in patients whose bones are weakened by a malignant haematological process, and proposes preventive measures in order to avoid accidents.

Aged↗
PubMed2000

Electric double-sleeved vacuuming microtrephine for lens refilling.

An automated electric double-sleeved vacuuming microtrephine has been developed that consistently creates a 0.8 to 1.0 mm tear-free hole in the anterior lens capsule. This hole is required for lens refilling to retain accommodation after cataract removal. The trephine is double-sleeved. The stainless-steel outer sleeve vacuums the internal anterior capsule; the stainless steel rotating inner sleeve, which has a blade on the head, then slides forward and cuts the taut anterior capsule. All manipulations are controlled automatically by depressing a foot pedal. Using this instrument, a 0. 8 to 1.0 mm tear-free microhole in the anterior capsule was created successfully in 80% of excised pig (n = 30) and eye-bank (n = 10) eyes. This trephine will be useful for lens refilling in the future.

Animals↗