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PubMed1997

[No-stitch phacotrabeculectomy using modified punch technique].

BACKGROUND: Combined cataract-glaucoma surgery is associated with a higher rate of intra- and postoperative undesired reactions than if each procedure is performed separately. We therefore investigated weather use of a special punch for trephination of a fistula opening in the area of the scleral tunnel could both reduce the rate of complications and improve regulations of pressure. METHOD: The modified procedure was performed in 22 patients. After phacoemulsification and implantation of a foldable lens through a 3.3 mm wide scleral tunnel, a 1.1 mm wide trephination opening was made in the lower wound flap using a specially designed punch. Without stitching the tunnel, the fistula was checked and the operation ended by suturing the limbus-based conjunctival flap. RESULTS: The rate of immediate postoperative complications was markedly reduced by that procedure. A postoperative hyphema did not occur in any patient. The incidence of fibrin exsudation was also considerably diminished. With regard to the medium-term stabilization of pressure, our method was slightly better than those reported in other studies. CONCLUSIONS: In light of the good results achieved with the modified procedure described here for the first time, a rethinking of the strict indications for this type of intervention in patients with cataract and simultaneous open-angle glaucoma is warranted.

Aged↗
PubMed1990

[Surgery of the eyelid edge--references for general practice].

a) Punctum plasty (eversion of the lacrimal point): This simple method results in a permanently enlarged punctum. A 4-0 silk suture is passed through the vertical part of the canaliculus and the conjunctiva, drawing them together very tightly. The thread falls out after 4-6 weeks. b) Management of trichiasis: Electrolysis of misdirected lashes leads to contraction and renewed misdirection. This disadvantage is avoided by excising the lashes with a 1 mm trephine. The trephine must follow the direction of the lash exactly, so that a complete cylinder including the hair and root can be removed. The resulting small defect heals quickly without contraction.

Dacryocystorhinostomy↗
PubMed1985

[Needs and technical prerequisites of an improved supply of donor material for penetrating keratoplasty].

The supply of donor material for keratoplasty is still considered a problem in many clinics. Preservation of donor tissue makes it possible to improve material selection. As far as the grafting of typed corneas is concerned, corneal organ culture offers a valuable time interval for planning the operation. In these preservation techniques the transplanted tissue is trephined from the endothelial side. With an optimal trephining technique the number of viable endothelial cells transplanted can be increased.

Corneal Transplantation↗
PubMed2005

Endonasal endoscopic assisted replacement of lacrimal drainage tubes.

PURPOSE: To describe an endonasal endoscopic assisted replacement of migrated or lost Lester-Jones (LJ) tubes. METHODS: In three consecutive cases of LJ tube migration or loss and an absent obvious transconjunctival tract, a curved paediatric Lusk ball-probe was passed under endoscopic visualization to the conjunctival surface through the internal nasal osteum. The drainage tube was then passed over the tip of the probe and replaced by retracting the probe back into the nose. RESULTS: In all cases, the drainage tube was successfully replaced using an endonasal endoscopic assisted technique. None of the cases, done 1-7 weeks after tube migration or loss, required the use of a K-wire and trephine for tube re-insertion. CONCLUSION: The conjunctivodacryocystorhinostomy tract appears to be retained following LJ tube migration or loss in selected cases. It can be accessed endonasally, allowing external tube replacement without the need for a repeat trephine.

Aged↗
PubMed2006

Bone marrow involvement in follicular lymphoma: comparison of histology and flow cytometry as staging procedures.

Bone marrow (BM) examination is a routine staging procedure in follicular lymphoma (FL). Commonly, both BM histology as well as flow cytometry (FCM) of BM aspirates are performed. In order to compare the diagnostic value of these two techniques, we retrospectively evaluated trephine BM biopsies and listmode data of patients with a confirmed diagnosis of FL, obtained in parallel during a 5-year period. One hundred and thirty nine specimens from 91 patients with FL were eligible for analysis. After joint review, nine cases (6.5%) were reclassified, either in histology (six cases) or FCM (three cases). Seventy nine specimens (57%) showed no infiltration with both methods. Sixty specimens (43%) were scored positive for BM involvement by any of the two techniques. Concordant positive results were obtained in 41 cases (68% of positive BM). False negative results were obtained by FCM in 14 cases (23% of positive BM) and by histology in five cases (8%). Discrepant results between BM histology and FCM are frequent in patients with FL, most likely due to the predominantly paratrabecular infiltration and fibrosis typical for FL. Due to the lower false negative rate, trephine BM biopsy remains crucial for the detection of BM involvement in FL.

Biopsy↗
PubMed2004

CD10 expression in extranodal dissemination of angioimmunoblastic T-cell lymphoma.

Angioimmunoblastic T-cell lymphoma (AITL) is a systemic disease that often has evidence of extranodal involvement at presentation. In a recent study of lymph nodes in AITL, we showed that the neoplastic T cells in most cases can be identified by aberrant expression of CD10. The aim of this study was to investigate whether CD10 expression by the neoplastic T cells is maintained in extranodal sites. Ten cases of AITL with histologic and immunophenotypic evidence of extranodal dissemination were studied. Seven cases of peripheral T-cell lymphoma unspecified (PTLu), that included biopsies of involved extranodal sites, two cases of enteropathy type T-cell lymphoma (ETTL), and one case of extranodal NK/T lymphoma, nasal type were selected as controls. Diagnostic lymph node biopsies and biopsies of extranodal sites were reviewed. PCR for T-cell clonality and single layer immunostaining for CD3, CD20, CD10, and CD21 and double layer immunostaining for CD20/CD10 were performed. All 10 cases of AITL had characteristic histologic features and molecular evidence of the disease in lymph node biopsies. In these cases, aberrant CD10 expression was maintained in the lung, cecum, tonsil, nasopharynx, and one of six involved bone marrow trephines. In these extranodal biopsies, the distribution of CD10-positive tumor cells correlated with that of the follicular dendritic cell meshwork (FDC). The five bone marrow trephines that lacked aberrant CD10 expression were devoid of morphologic and immunohistochemical evidence of FDC. In these five cases, there was evidence of aberrant CD10 expression in other involved sites that had FDC. The neoplastic cells in PTLu, ETTL, and extranodal NK/T lymphoma, nasal type were CD10 negative. Our data show that aberrant CD10 expression is a useful phenotypic marker for diagnosis of AITL in most involved extranodal sites, except bone marrow, and suggest a possible role of FDC in the pathogenesis of AITL.

Adult↗
PubMed1982

The reaction of the dura to bone morphogenetic protein (BMP) in repair of skull defects.

Trephine defects in the adult rat skull 0.8 cm in diameter, which do not spontaneously heal, were filled with a bovine bone morphogenetic protein (BMP) fraction. The defects healed not only by bony ingrowth from the trephine rim, but also by proliferation of pervascular mesenchymal-type cells (pericytes) of the dura mater. Under the influence of BMP, dural pericytes differentiated into chondroid and woven bone. Between three and four weeks postimplantation, sinusoids formed and the woven bone remodelled into lamellar bone. Concurrently, blood-borne bone marrow cells colonized the bone deposits, and the diploe were restored. Demonstrating that it is soluble in interstitial fluid, and diffusible across a nucleopore membrane (which isolated the bony margins of the skull), BMP induced new bone formation in the underlying dura and complete repair of the defect. The response of the dura to the BMP fraction produced more new bone than the response to allogeneic bone matrix. The BMP-induced repair was dose dependent; the quantity of new bone was proportional to the dose of the implanted BMP.

Animals↗
PubMed1997

Extradural endoscopic dissection of the anterior skull base.

A study was conducted from February 29, 1996, to March 28, 1996, at the University of Brno's Pathology Institute in the Czech Republic to explore the possible application of craniofacial intracranial endoscopic techniques through minimal skin incisions and trephines in fresh cadavers (3 to 12 hours old). Through the trephines the dura was totally dissected from the bone. After this dissection a standard bicoronal incision and a full craniotomy was performed to assess the integrity of the meninges. This minimally invasive dissection of the skull base with the aid of an endoscope is characterized by fewer skin incisions, thereby avoiding the exposure of subcutaneous tissue, muscle, cranial bone, and meninges. We find that it is possible to accomplish an accurate and extensive intracranial dissection with the aid of an endoscope. The potential of this technique is important for craniofacial surgery as well as for neurosurgery. The objectives of this study were [1] to explore endoscopically the craniofacial anatomy to determine the best approach and the optimal method for dissecting endocranial structures, and [2] to achieve a safer and more accurate dissection of the skull base, evaluating advantages of endoscopic surgery as an alternative method for the treatment of craniofacial and neurosurgical pathologies.

Adolescent↗
PubMed1998

Fixation of osteotomies using bioabsorbable screws in the canine femur.

The purpose of this study was to compare the healing properties of femoral osteotomies fixed by bioabsorbable screws (20:80 polyglycolic copolylactic acid copolymer) to standard stainless steel screws of a similar design in a dog femoral model. Two osteotomies were used, the trephine osteotomy (10 mm diameter) in the metaphyseal lateral femoral condyle and in the femoral diaphysis, and a unilateral osteotomy in the lateral femoral condyle. Two months after the trephine osteotomies, the femurs that contained the polymer screws were not significantly different in mechanical strength from the femurs treated with the stainless steel screws, either in the diaphyseal or metaphyseal model. There was no histological difference in bone healing between the metallic and polymer screws for all periods (2, 9, and 17 months). There was no adverse inflammatory response to the polymeric or metallic screws. By month 17, the polymer screws were resorbed completely. All the diaphyseal screw tracks had healed with bone and areas of remodeling were evident in two specimens. For the femoral condyle osteotomy model at 2 months, the polymer screws were present and intact, and all osteotomies healed with no evidence of inflammation. By 9 months, only one specimen had polymeric material left in the screw track. At 15 months, the screw tracks still were present but no evidence of any polymer remained. The tracks were filled with fibrous and adipose connective tissue. All osteotomies stabilized with either bioabsorbable polymer screws or stainless steel screws did heal satisfactorily without any complications, inflammation, or osteolysis. The polyglycolic polylactic acid copolymer may have a clinical role as a bioabsorbable material without the concerns for the osteolysis, foreign body reaction, and sterile abscess formation that have occurred with bioabsorbable fixation methods in the past.

Absorbable Implants↗
PubMed1991

Computerized method for rotational autokeratoplasty.

The aim of our study was to formulate the procedure of rotational autokeratoplasty; that is, design the computer system and software necessary to automatically define the parameters of the problem. To achieve this, we used a CCD camera (Nikon) and a microcomputer with an integrated IMAGENIA (Biocom) interface software card (512 x 512 pixels and 100 gray levels), which permitted acquisition and digitalization of photographs of the lesioned cornea. Digitization of the image allowed us to determine the coordinates (x,y) of the points that lay on the lesion periphery as well as the coordinates of the corneal center; i.e., the geometric center of the cornea. The center of trephination and the optimal diameter of trephination can then be calculated as a function of a point situated on the lesion edge.

Corneal Transplantation↗
PubMed1994

Transplantation of corneal endothelial cells using a cell carrier device.

Penetrating keratoplasty is currently the only treatment for corneal endothelial dysfunction. Although corneal transplantation has a high success rate, a few problems still remain, such as the limited availability of donor grafts, the change in refraction after penetrating keratoplasty, and the higher chance of immune rejection. In this study, a coated hydrogel lens (Chiron Ophthalmics Inc., Irvine CA, U.S.A.) has been used as a carrier to transplant cultured homologous kitten and rabbit corneal endothelial cells into adult cats and rabbits. The transplantation procedure was the same in both species. Corneal endothelial cells from homologous rabbits or cats were seeded on coated hydrogel lenses and cultured until they reached a complete monolayer with an average cell density of 2,500 cells/mm2. Five weeks before transplantation surgery, corneal endothelial cells were scraped to induce corneal edema. The cell carrier device was then transplanted as follows: a trephine cut (7.7 mm) was made into the stroma, producing an outer corneal plug. The inner cornea was then cut by using a 5.5-mm trephine, and this inner plug was discarded. The implant was inserted and the outer corneal plug was sutured back into place. Corneas cleared completely within 3 days in both rabbits and cats, and stayed clear for an average of 40 days in rabbits and 50 days in cats. The histopathological evaluation of the rejected grafts showed vascularized retrocorneal membrane formation in cats, whereas in rabbits severe cellular infiltration of the stroma with neovascularization occurred without retrocorneal membrane formation.

Animals↗
PubMed2001

Bacterial contamination of human organ-cultured corneas.

PURPOSE: The aim of this study was to detect and identify bacterial contaminants in human corneoscleral tissue after organ culture storage. METHODS: Seventy-two corneoscleral rims and corneal buttons trephined from organ cultured corneoscleral discs using aseptic technique and 45 organ-cultured donor corneoscleral rims postpenetrating keratoplasty) were subjected to a mechanical extraction technique using a Stomacher laboratory blender. As a control, 28 of the corneoscleral rims and buttons were halved; one half of each corneoscleral rim and button was decontaminated in formalin for 48 hours before thorough washing in balanced salt solution. Corneal specimens, culture medium, and transport (5% dextran) medium were cultured in brain-heart infusion broth at 37 degrees C for 5 days. Bacterial isolates were identified after culture of turbid enrichment broth. RESULTS: Bacterial contamination was demonstrated in 29% (21 of 72) of the corneoscleral rims and 15% (11 of 72) of the corneal buttons that were trephined aseptically from corneoscleral discs and in 29% (13 of 45) of postkeratoplasty corneoscleral rims. Bacterial contaminants were not isolated from controls. Isolated microorganisms included coagulase-negative Staphylococcus, Staphylococcus aureus, Streptococcus viridans, Pseudomonas sp, and Bacillus sp. A correlation was not demonstrated between contamination and cause of death, death to enucleation, death to culture time, or time in culture. Postkeratoplasty endophthalmitis was not evident in the patients who had received corneal buttons from those corneoscleral discs that had contaminated corneoscleral rims. CONCLUSIONS: Bacterial contamination exists in corneoscleral tissue after organ culture storage. The difference in distribution of bacteria and percentage of contamination between the peripheral and central corneas causes us to question the value of routine postpenetrating keratoplasty corneoscleral rim cultures.

Bacteria↗
PubMed2003

Impact of preoperative corneal curvature on the outcome of penetrating keratoplasty in keratoconus.

PURPOSE: To assess the impact of the patient's preoperative corneal curvature on the refractive outcome after penetrating keratoplasty (PK) in keratoconus before and after suture removal. PATIENTS AND METHODS: In this retrospective cross-sectional clinical study, 236 keratoconus patients (mean age 37 +/- 11 years) were divided into four groups based on their preoperative keratometric (K-) readings: group 1, <50 diopters (D) (n = 24); group 2, <60 D (n = 52); group 3, > or =60 D (n = 101); group 4, irregular corneal shape with unmeasurable K-reading (n = 59). An 8.0/8.1-mm central round PK was performed using 193 nm Meditec excimer laser trephination along metal masks with eight "orientation teeth/notches." A 16-bite double running cross-stitch suture was applied in all cases. Postoperative examinations were performed before removal of the first suture (ie, 12 months) and after removal of the second suture (ie, 18 months). The outcome measures included central power (C-power), keratometric astigmatism (AST), surface regularity index (SRI), surface asymmetry index (SAI), spherical equivalent (SEQ), refractive cylinder (Cyl), and best corrected visual acuity (BCVA). In addition, the regularity of Zeiss keratometry mires was classified semiquantitatively (0, regular; 1, mildly irregular; 2, moderately irregular; 3, unmeasurable). RESULTS Before/after suture removal, median C-power was 43.4/43.3 D; AST was 3.0/3.0 D; SAI was 0.6/0.6; SRI was 0.9/0.9; Cyl was 2.5/2.5 D; BCVA was 0.7/0.7. After suture removal, the percentage of regular keratometry mires increased from 37% to 61%. Comparisons among the four groups revealed no significant differences for any parameters tested either before or after suture removal. CONCLUSIONS With laser trephination and a double running suture, the refractive and visual outcome of PK for keratoconus seems to be independent on the patient's preoperative corneal curvature or irregularity. Suture removal did not effect an increase of corneal astigmatism but did increase the proportion of regular keratometry mires. Thus, our policy of not performing PK in keratoconus eyes before the patient becomes contact lens intolerant is well supported.

Adolescent↗
PubMed1985

Adult respiratory distress syndrome associated with miliary tuberculosis.

Three patients with respiratory failure resulting from miliary tuberculosis had a characteristic clinical presentation that included a long history of a prominent cough, dyspnea, weight loss, tachycardia, tachypnea, pulmonary adventitious sounds, and hepatomegaly. Hematologic investigation showed a normal white cell count with marked left shift in the morphology of white cells in all three patients, and evidence of disseminated intravascular coagulation in one patient. In only one patient was the initial sputum positive for acid-fast bacilli; in the others, invasive diagnostic procedures including lumbar puncture, bone marrow trephine, and open-lung biopsy were necessary for diagnosis. Miliary tuberculosis should be suspected in patients with adult respiratory distress syndrome of unknown etiology. Simple diagnostic procedures such as sputum, bronchial brushings, and urine examination should be followed by bone marrow trephine, liver biopsy, transbronchial lung biopsy, and lumbar puncture if physical signs of meningitis are present.

Adult↗
PubMed1990

Combined use of subdural and intracerebral electrodes in preoperative evaluation of epilepsy.

For intracranial recording of partial seizures considered to originate from one of the temporal or frontal lobes, the team in the Utrecht Academic Hospital has used subdural, multicontact, flexible electrodes since 1972. These are introduced through bilateral, frontocentral trephine holes and are manipulated under fluoroscopy to cover most of the cerebral convexity. It became evident that in many patients, additional placements to record from intracerebral structures were indispensable. Therefore, using the same trephine holes, an additional 2 to 4 depth electrodes were stereotactically implanted in the mesial temporal and/or frontal structures, as appropriate. An extensive intra- and extracerebral spatial representation of the epileptogenic zone was thus obtained. We report here the methods for manufacturing and applying these electrodes and our clinical experience with 28 patients. The results obtained so far stress the value of combining subdural and depth electroencephalographic monitoring in the presurgical selection of patients suffering from medically refractory complex partial seizures. By miniaturizing the electrodes, extensive areas of the brain can be investigated without craniotomy or multiple burr holes.

Adult↗
PubMed1977

Value of bone marrow biopsy in the diagnosis of amyloidosis.

Amyloid involvement of the bone marrow is not commonly diagnosed before necropsy. Paraffin sections of the trephine bone biopsy specimen are superior to marrow aspiration cell smears for the antemortem diagnosis. Thirteen cases of amyloidosis were diagnosed from the bone biopsy specimen during a ten-year period. Amyloid was detected in only two of the corresponding aspirates. Three morphologic patterns of marrow involvement were found: vascular, focal extravascular/perivascular, and diffuse. Five (38%) of the cases were associated with multiple myeloma. An abnormal immunoglobulin was detected in the serum or urine or both in ten of 11 cases when determined. Although the bone marrow may not be the best site for the diagnosis of amyloidosis, it should not be neglected and marrow biopsies taken for other diagnostic reasons may "incidentally" reveal amyloid. Amyloidosis should be included in the list of non-primary hematologic conditions of the bone marrow in which the trephine biopsy may prove useful for diagnosis.

Adult↗
PubMed2003

Multiplex RT-PCR for the detection of common BCR-ABL fusion transcripts in paraffin-embedded tissues from patients with chronic myeloid leukemia and acute lymphoblastic leukemia.

Diagnosis of chronic myeloid leukemia and acute lymphoblastic leukemia requires the investigation of the Philadelphia chromosome translocation t(9;22) or the molecular detection of BCR-ABL fusion transcripts. Determination of the type of fusion transcript is crucial for quantitative molecular monitoring the course of the disease during treatment. Histopathologists, who usually use formalin-fixed tissues, may be confronted with the need to investigate the BCR-ABL rearrangement when evaluating tumor forming infiltrates and bone marrow trephines from patients presenting with chronic myeloproliferative disorders. Therefore, we have established a one-tube multiplex RT-PCR for the detection of common BCR-ABL fusion transcripts (b2a2, b3a2, e1a2) in routinely processed tissues and bone marrow trephines with respect to the inevitable fragmentation of ribonucleic acids in these specimens. RT-PCR products allow distinct and unequivocal differentiation of the underlying fusion in either the Major- or minor-breakpoint cluster region. Detection of BCR-ABL fusion transcripts by multiplex RT-PCR in routinely processed and fixed tissues is a time- and cost-sparing tool for definite diagnosis of typical chronic myeloid leukemia and Philadelphia chromosome positive acute lymphoblastic leukemia.

Bone Marrow Cells↗
PubMed2001

New lamellar keratoplasty techniques: posterior keratoplasty and deep lamellar keratoplasty.

Posterior keratoplasty is a new surgical technique that may be valuable in treating patients with corneal decompensation secondary to endothelial dysfunction. There are currently two approaches to posterior keratoplasty. In the first approach, a corneal flap is created using a microkeratome (similar to laser in situ keratomileusis flap), and posterior stromal tissue is excised (by trephination or excimer laser keratectomy). In the second approach, a deep stromal pocket is created across the cornea through a superior scleral incision. A custom-made flat trephine is inserted into the pocket to excise a posterior lamellar disc. Preliminary studies have shown the feasibility of performing these techniques in sighted human eyes. Despite potential advantages, further clinical studies are needed to determine whether these techniques reduce interface scarring, astigmatism and graft rejection, improve visual outcomes, or are potentially an alternative for penetrating keratoplasty.

Corneal Diseases↗