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PubMedDate not supplied

Iowa PK Press for donor corneas--a comparative study of donor corneal shape.

BACKGROUND: A new cornea press for cutting donor corneal buttons from the endothelial side, the Iowa PK Press, is described. Major modifications of the Bourne Press include a spring-activated piston without lateral sway, a centering device for a Teflon cutting pad, and the ability to accommodate a wider range of trephine sizes (6.2 mm to 10.0 mm). METHODS: The Iowa PK Press was compared with the Bourne Corneal Press and trephination by hand in a series of 15 donor cornea trephinations. Measurements taken from photographs of the buttons included endothelial diameter, epithelial diameter, and edge angles. RESULTS: The Iowa PK press cut buttons that had a slightly larger epithelial and endothelial diameter when compared to hand trephination (p < .05, analysis of variance) with less undercutting of the endothelial surface. There was no statistically significant difference in epithelial and endothelial diameters, eccentricity, or edge angles between the two presses. CONCLUSIONS: The Iowa PK Press is more versatile than the Bourne Press in terms of the potential range of diameter of corneal buttons that can be created.

Cell Size↗
PubMed1992

Combined CT-guided biopsy and cytology in diagnosis of bony lesions.

The results of 44 trephine (OD 1.4-4 mm) biopsies and 39 fine needle (0.7-0.9 mm) aspirations of skeletal, mainly vertebral, lesions performed under CT-guidance in 54 patients were evaluated. The fine needle sample was aspirated through the trephine as a complementary procedure in 29 patients and a fine needle aspiration only was performed in 10 patients. Trephine biopsy only was performed in 15 patients. Sufficient material for histologic and cytologic analyses was obtained in 93% (41/44) and 97% (38/39) and a correct benign or malignant diagnosis was obtained in 84% (37/44) and 90% (35/39), respectively. Among the combined examinations the fine needle aspiration alone was diagnostic in 2 cases while the trephine specimen alone provided diagnostic material in 2 cases. In 24 cases both the cytologic and histologic samples were adequate for diagnostic purposes. In one case both methods gave false-negative results. The combined use of cytologic and histologic samples in CT-guided bone biopsies increased diagnostic accuracy. The aorta was perforated once with a 1.4-mm needle but without sequelae. CT-guided bone biopsy was found to be a safe, reliable and cost-efficient method.

Adult↗
PubMed1990

Effects of epikeratoplasty on the host cornea. An experimental study.

The effects of epikeratoplasty on the host cornea was studied using albino rabbits. Eyes underwent midperipheral partial trephination alone (group I), midperipheral partial trephination and peripheral undermining (group II), midperipheral partial trephination and circular keratectomy (group III), and trephination, peripheral undermining, and circular keratectomy (group IV). Corneal topography was assessed weekly using keratometry and photokeratoscopy. All eyes showed central corneal steepening with enhancing effects of increased surgical manipulation. Results were stable by 4 weeks in all eyes. Histopathologic evaluation revealed a constant wound depth of approximately 0.1 mm, with an increased accumulation of glycosaminoglycan material at the base of the wound. This was stained with PAS and alcian blue. Steepening of the host cornea may be another reason for lack of predictability and refractive regression following epikeratoplasty.

Animals↗
PubMed1989

[Configuration of corneal incisions with the excimer laser: an experimental study].

The potential applications of an ophthalmic excimer laser at 193 nm include its use as a precise trephine in keratoplasty procedures. In a series of 20 human autopsy and 40 pig cadaver eyes the histological and ultrastructural results of donor and recipient trephination and full-thickness corneal grafting using new mask systems were evaluated. In comparison with other beam delivery systems the "open mask system" allows the performance of excimer laser trephinations with reproducible wound configuration and geometry, with easy handling and high reliability. This technique enables the surgeon to surmount the mechanical limitations of cutting direction and makes non-circular trephinations possible.

Animals↗
PubMed1986

Fragment filtration: a method for the accurate determination of flow cytometric kinetic data from bone marrow aspirates.

The extent to which bone marrow obtained by conventional aspiration is contaminated by peripheral blood has been confirmed and quantitated. In marrow aspirates from normal subjects the median percentage of nucleated cells that had originated from the peripheral blood was 32% (range 2.5%-64%), in patients with acute leukemia 23% (range 0.5%-96.5%), in patients with chronic leukemia 59% (range 17%-76%), and in patients with lymphoma 31% (range 0.5%-74%). Flow cytometric (FCM) DNA analysis of conventional marrow aspirates from a range of subjects significantly underestimated the proportions of S-phase cells present, when compared with results from trephines obtained at the same time. Having shown, using 51Cr-labeled red cells in mice, that circulating red cells do not reenter the marrow parenchyma, a mathematical correction for contaminating blood similar to that described by Holdrinet et al. was devised. This correction improved the S-phase cell estimate from aspirated marrows, and the corrected values were not significantly different from values from paired trephine samples. A previously described technique for collecting fragments by filtration of aspirated marrow has been adapted for FCM analysis as a more direct way of overcoming problems due to blood contamination. This method was shown to yield estimates of S-phase cells not significantly different from those in paired marrow trephines and offers an alternative to routine trephine biopsies for FCM analysis of marrow cell kinetics.

Animals↗
PubMed1993

[Diagnosis and therapy of chronic subdural hematoma].

The authors evaluate a group of 72 patients with the diagnosis of chronic subdural haematoma (cSDH). All subdural collections were confirmed on a computer tomograph. Sixty-nine patients were operated by trepanation and drainage into a closed system which was maintained for a maximum of five days. Three patients with a hyperdense CT finding were subjected to extended trepanation or craniectomy with membranectomy. The CT picture made on the 2nd-4th day after operation revealed a persisting subdural collection in 35% of the patients subjected to trephination. The authors were concerned with the problem whether this percentage makes trephination with drainage controversial as the only universal therapeutic method in cSDH. Nevertheless successful reinsertion of the drain (85%) is in favour of trephination although drainage from the first trephination in not always the definite solution. Conversely revision by craniotomy was a failure in 7 patients where the drainage method was not successful. Radical surgery proved useful only in the initial period in patients who despite a chronic course had on CT a hyperdense collection. The influence of the site, volume of collection, lateral overpressure and possibly a subsidiary CT finding could not be proved on a statistically significant scale, therefore the authors did not use these CT markers when selecting surgical intervention.

Adult↗
PubMed1988

Cranial surgery in ancient Peru.

Trephination is the oldest known surgical technique. Peru has been recognized as a major source of ancient trephined skulls, many of which date back 2300 years. This presentation reviews from a neurosurgical perspective many of the archaeological studies performed on these skulls. Comparative osteology has shown that almost 70% of patients survived the procedure. The various instruments, hemostatic agents, anesthetics, surgical techniques, and cranioplasties used are reconstructed from the anthropological literature. The possible reasons for the use of trephination are discussed. Analysis of the data leads to the conclusion that, despite their rudimentary knowledge of disease, the ancient Incas must have had some knowledge of anatomy and proper surgical procedure.

History, Ancient↗
PubMed1988

[Decompressive trepanation in therapy refractory brain edema].

Already in 1905 and 1908 Harvey Cushing carried out decompression operations for the relieving of pressure in inoperable glious tumours and posttraumatic cerebral oedmas. This surgical method of trephination, which later-on was adopted by many other surgeons, was based on the method of the prevention of an incarceration of the mesencephalon in the tentorial slit by an enlargement of the reserve space in the interior of the crane. In case of a posttraumatic cerebral oedema, besides Heppner's work group practically all other authors operated in pronounced late stages of the incarceration. The results obtained were bad. Heppner worked on the basis of a wider indication, operated earlier, and obtained better results. The intervention should be performed on the basis of continuous preoperative measuring of the cerebral pressure. By means of calculations and modelling we were in a position to demonstrate that on both sides very large trephination areas with the relation of the radius of the trephination area to the radius of the head being 2 to 3 are necessary for achieving a sufficient decrease of the pressure by about 20 to 30 torr.

Brain Edema↗
PubMed1998

Role of staging bone marrow examination in children with Hodgkin disease.

PURPOSE: To determine the value of bone marrow trephine biopsy as part of the clinical staging for children presenting with Hodgkin disease. PATIENTS AND METHODS: A retrospective study of pre-treatment bone marrow examinations was undertaken to examine the value of bone marrow staging in children with Hodgkin disease. The records of 122 children, diagnosed with Hodgkin disease at Texas Children's Hospital between February 1960 and July 1996 were reviewed. Age, sex, complete blood counts (CBC), pathology, and clinical and pathological staging results were tabulated. RESULTS: Information was complete for analysis in 110 patients. Bone marrow trephine biopsies identified Hodgkin disease in 2/110 patients (1.8%). The patients with bone marrow disease had clinical stage IIIB disease prebiopsy. Positive bone marrow biopsy results did not effect a change in therapy, and the small number of positive cases do not allow any prediction as to prognosis. CONCLUSION: There is no role for bone marrow trephine examination in children with clinical stage I-IIIA Hodgkin disease.

Adolescent↗
PubMed1976

Bone marrow manifestations of Hodgkin's disease.

Bone marrow trephine biopsies were performed on 107 previously untreated patients with Hodgkin's disease (HD). Fifteen patients (14%) exhibited bone marrow involvement. These consisted of two of three patients (67%) with lymphocyte depletion, six of 27 patients (22%) with mixed cellularity, five of 64 patients (8%) with nodular sclerosis, and two who were unclassified. Twelve patients manifested a diffuse pattern of involvement; three, a focal pattern. In eight patients more than 70% of the marrow biopsy was replaced by Hodgkin's tissue, in one patient 50% of the marrow biopsy was replaced, and in six patients less than 30% of the marrow biopsy was replaced. Typical Reed-Sternberg (RS) cells were found in the trephine biopsies in 13 of the 15 patients and mononuclear RS variants in two. Bone marrow involvement was the only evidence of stage IV disease in 10 of the 15 patients. In addition to the 15 patients with initial involvement with HD, 11 patients without marrow involvement exhibited granulomas (six) and benign lymphocytic aggregates (five) in their trephine sections. Hematological parameters were studied in all pretreatment patients. Only in the nodular sclerosis group were these parameters useful in differentiating patients with and without Hodgkin's involvement of the marrow. Seventeen additional patients who had been previously treated at the time HD was demonstrated in their bone marrow were also studied. Large areas of necrosis were frequently seen in previously treated patients and one patient demonstrated cryptococcosis in the bone marrow.

Adolescent↗
PubMed2004

Diagnostic laparoscopy and diverting sigmoid loop colostomy in the management of civilian extraperitoneal rectal gunshot injuries.

BACKGROUND: This prospective study reviews the management of isolated civilian extraperitoneal rectal gunshot injuries using a protocol of diagnostic laparoscopy and abdominal wall trephine diverting loop colostomy, without laparotomy, distal rectal washout and presacral drainage. METHODS: Patients admitted to the trauma unit at Groote Schuur Hospital between January 2000 and December 2002 with a rectal injury were evaluated. A rectal injury was confirmed by digital rectal examination and proctosigmoidoscopy. Missile peritoneal violation was excluded by diagnostic laparoscopy. Normal laparoscopy was followed by creation of a diverting sigmoid loop colostomy through an abdominal wall trephine, without a laparotomy. No distal rectal washout or presacral drainage was performed. RESULTS: Of the 104 patients admitted with 106 rectal injuries, 20 (19.2 per cent) qualified for inclusion in the study. All had sustained low-velocity gunshot injuries of which 18 exhibited a transpelvic trajectory. Diagnostic laparoscopy was normal and a trephine diverting loop sigmoid colostomy was performed in all 20 patients. No pelvic sepsis occurred. Two patients developed rectocutaneous fistulas, both of which resolved without surgical treatment. Nineteen stomas have since been closed. CONCLUSION: Low-velocity gunshot injuries isolated to the extraperitoneal rectum can be managed safely by laparoscopic exclusion of intraperitoneal missile penetration and diverting sigmoid loop colostomy, without laparotomy, distal rectal washout or presacral drainage

Adolescent↗
PubMed2004

[Results of the first 1,000 consecutive elective nonmechanical keratoplasties using the excimer laser. A prospective study over more than 12 years].

BACKGROUND AND PURPOSE: The purpose of this prospective clinical cross-sectional study was to analyse indications, intraoperative, perioperative and postoperative pecularities and complications as well as postoperative functional and morphologic results of the first 1000 consecutive elective round laser keratoplasties. PATIENTS AND METHODS: The age of the 480 females and 520 males (362 x keratoconus), who had been operated on between 07/1989 and 04/2002 ranged from 20 to 92 years (mean 55+/-19). A total of 6 microsurgeons performed 718 x PK only, 222 x a triple procedure and 60 x additional IOL manoeuvres. Recipient and donor trephinations were accomplished with an 193 nm excimer laser (Carl Zeiss Meditec, Jena, Germany) from the epithelial side. RESULTS: In 895 eyes with perioperative corneal erosion, epithelial healing took not more than 3 days in half of cases. During a follow-up period of 1.9+/-1.5 years, in 35 eyes episodes of acute diffuse (8 irreversible) and in 12 eyes episodes of chronic focal (5 irreversible) endothelial immunologic graft reactions (4.7%) occurred between 6 weeks and 4.7 years after PK. Before/after suture removal, median values of astigmatism were 1.5 diopters (D)/2.5 D refractive, 3.0 D/3.3 D keratometric, and 4.0 D/4.2 D topographic. Best-corrected visual acuity was 0.50/0.60, respectively. CONCLUSIONS: More than 12 years of experience with this new technique indicate that besides optical advantages, nonmechanical trephination does not cause intraoperative or postoperative disadvantages for the patient. Under standardised surgical conditions a massive increase of astigmatism after suture removal seems to be avoidable with laser trephination in most cases due to reduction of decentration,"vertical tilt" and especially "horizontal torsion".

Adult↗
PubMed2000

[Long-term results of combined glaucoma and cataract surgery. Intraocular pressure and visual acuity follow-up].

BACKGROUND: The aim of this investigation was to ascertain the long-term results of intraocular pressure and visual acuity after combined glaucoma and cataract surgery. PATIENTS AND METHODS: Between 1994 and 1997, 65 eyes underwent Pham's sclerectomy and at the same time 65 eyes underwent Elliot's trephination with scleral flap. Both procedures were combined with phacoemulsification and implantation of a posterior chamber lens. The mean follow-up was 21.9 +/- 11.0 months. RESULTS: The IOP of eyes that underwent Pham's sclerectomy decreased from 21.4 +/- 3.3 mmHg to 14.9 +/- 2.7 mmHg and of eyes that underwent Elliot's trephination from 24.6 +/- 7.3 mmHg to 15.8 +/- 2.6 mmHg. Thirty percent of the eyes with Pham's sclerectomy and 25% with Elliot's trephination required an additional medication. In both procedures the overall visual acuity increased by three lines. CONCLUSIONS: These results of combined glaucoma and cataract surgery confirm their efficiency. From the economical aspect, combined glaucoma and cataract surgery has gained increasing significance.

Aged↗
PubMed1998

[Correlation between semi-quantitative classification of corneal topography and the coefficient of Fourier transformation after non-mechanical perforating keratoplasty].

BACKGROUND: Semiquantitative classification of corneal topography after penetrating keratoplasty has the potential for focusing information about the areal dioptric power of the cornea. The purpose of this study was to objectify the procedure of manual semiquantitative classification using a Fourier transform of corneal topography power data and to correlate both methods. PATIENTS AND METHODS: Fifty patients each (30 keratoconus, 20 Fuchs dystrophy) underwent nonmechanical trephination (excimer laser MEL60, Aesculap-Meditec, Jena) in penetrating keratoplasty. All procedures (7.5-mm trephination diameter in Fuchs, 8.0 mm in keratoconus, double-running 10-0 nylon suture) were done by one surgeon. Pre-, intra- and postoperative treatment were identical. At the follow-up examinations, the keratometric astigmatism, qualitative and quantitative criteria of the automatic videokeratography, visual acuity and refraction were assessed. Corneal topography was classified both manually and based on Fourier coefficients. RESULTS: After a mean follow-up of 24 +/- 5 months, keratometric net astigmatism was 3.0 and 2.7 D with keratoconus and Fuchs dystrophy. Corneal topography analysis showed a higher orthogonality of the bow-tie shape and less asymmetry between opposite hemimeridians with increasing follow-up after keratoplasty. The semiquantitative classification showed a statistically significant correlation with the classification based on Fourier coefficients, especially with higher astigmatism and after suture removal (P = 0.04/0.01 before/after suture removal). DISCUSSION: After nonmechanical trephination, the semiquantitative classification of corneal topography can be synthetized using Fourier analysis of corneal dioptric power data. In the future, this method may be favored for prediction of potential best-corrected visual acuity after penetrating keratoplasty.

Adult↗
PubMed2006

Long-term refractive and visual outcome after penetrating keratoplasty only versus the triple procedure in Fuchs' dystrophy.

BACKGROUND: Long-term refractive and visual outcome after penetrating keratoplasty (PK) only and the triple procedure in eyes with Fuchs' endothelial dystrophy were assessed and compared. DESIGN: Retrospective, non-randomized, cross-sectional, clinical, single-centre study. METHODS: Ninety-two eyes of 87 patients were divided into two groups. Group 1 consisted of 28 eyes (mean age 62+/-13 years) that had undergone PK only and group 2 consisted of 64 eyes (mean age 69+/-10 years) that had undergone the triple procedure. Inclusion criteria were: (1) Fuchs' dystrophy, (2) central nonmechanical trephination, (3) double-running suturing technique and (4) availability of 'two-sutures-out' findings. In all eyes, a central trephination was performed (donor trephination from the epithelial side) using the 193-nm excimer laser along metal masks with eight 'orientation teeth/notches'. A double-running 10-0 nylon suture was applied in all eyes. Subjective refractometry (trial glasses), standard keratometry (Zeiss) and corneal topography analysis (TMS-1, Tomey) were performed in all eyes with 'two-sutures-in', 'one-suture-out', and 'two-sutures-out'. Main outcome measures included refractive cylinder, keratometric and topographic net astigmatism, keratometric and topographic central power, best-corrected visual acuity (BCVA), spherical equivalent (SE) of manifest refraction, surface regularity index (SRI), surface asymmetry index (SAI), and regularity of keratometry mires. RESULTS: The results were compared between the two groups (i.e. group 1 vs group 2) at various stages (i.e. 'two-sutures-in', 'one-suture-out', 'two-sutures-out'). Refractive cylinder in dioptres [D] was 2.5/2.0/2.5 vs 2.0/1.5/3.0, keratometric astigmatism [D] was 3.5/2.6/3.0 vs 3.5/3.1/3.5 and topographic astigmatism [D] was 3.9/4.1/4.9 vs 4.2/5.0/5.1. Keratometric central power [D] was 41.7/42.4/43.8 vs 41.5/41.9/43.3 and topographic central power [D] was 42.3/43.6/43.7 vs 42.6/41.8/44.3. BCVA was 0.5/0.6/0.6 vs 0.5/0.5/0.5. SE [D] was 0.0 /0.0/-0.5 vs -0.5/-0.5/-1.1. SRI was 1.5/1.1/1.0 vs 1.4/1.4/1.2 and SAI was 1.0/0.8/1.0 vs 1.3/1.2/1.0. The proportion of 'regular' and 'mildly irregular' keratometry mires was 44% / 69% / 68% vs 29% / 46% / 66%. The differences between the two groups did not reach statistical significance at any of the stages. CONCLUSIONS: Refractive and visual outcome after the triple procedure did not differ significantly from that after PK only. Therefore, we recommend the triple procedure in elderly patients with Fuchs' dystrophy and cataract to avoid delayed visual rehabilitation and a second surgical procedure.

Adult↗
PubMed2000

Aachen keratoprosthesis as temporary implant for combined vitreoretinal surgery and keratoplasty: report on 10 clinical applications.

UNLABELLED: A new keratoprosthesis was used during pars plana vitrectomy in order to test the optical quality, watertightness, short-term biocompatibility and handling of the new device. The implantability was also tested, given that this keratoprosthesis might in future be left in place for several months. This Aachen keratoprosthesis (Aachen-KPro) is developed to be used as permanent implant to restore vision in corneal blind patients. PATIENT AND METHODS: The Aachen-KPro was used during pars plana vitrectomy in 10 patients with opaque corneas. In four cases, trauma precipitated the ocular disease. Eye burn was the cause of corneal and retinal disorders in another four cases. One patient had a history of congenital glaucoma with myopia, and one of uveitis with corneal dystrophy. After trephination of 6.5 mm in diameter, the Aachen-KPro, composed of soft silicone rubber, was temporarily placed in the trephination hole. After completion of the vitrectomy, the Aachen-KPro was replaced by a 7 mm corneal graft. RESULTS: Intraoperative use of the Aachen-KPro allowed uncomplicated intraoperative handling, smooth adaptation to the corneal rim in the trephination hole, and an undistorted view of the central and peripheral retina. Leakage, even during scleral depression, could be avoided by individual suturing of the scleral rim. After a follow-up period of 1-10 months, the retina was still attached in all cases. The corneal graft was clear after surgery in four eyes, and edema was found in three cases. Amnion or conjunctiva was placed over three patients' transplants. CONCLUSION: We report the first temporary implantations of a new keratoprosthesis in 10 patients. Its flexibility and good optical qualities allowed control of intraoperative procedures. The outcome and prognosis of the vitreoretinal surgery and keratoplasty were related to the primary diagnosis. The Aachen-KPro has shown advantages, especially in eyes where the anterior eye segment is severely damaged by eye burn or previous surgical interventions. In the future, prolonged use of the Aa-chen-KPro is planned for selected eyes.

Adult↗
PubMed2005

Immunohistochemistry in bone marrow pathology: a useful adjunct for morphologic diagnosis.

Pathomorphological examination of trephine biopsies of the bone marrow (BM) represents a standard method for the diagnosis and staging of hematologic neoplasms and other disorders involving the BM. The increasing knowledge about the genetic basis and biology of hematologic neoplasms, as well as the recently proposed WHO classification system, provide the framework for an accurate diagnosis. Although conventional morphology remains the gold standard for paraffin-embedded BM trephines, immunohistochemical stainings have become an integral part of the diagnostic workup. Antibodies suitable for paraffin sections are generally applicable to BM trephines, but modifications of staining protocols may be necessary due to the alternative fixatives and decalcification procedures used for BM biopsies. The indications for immunostainings range from confirmation and classification of lymphoma involvement, subclassification of acute leukemias, and estimating blast counts in myelodysplastic and myeloproliferative syndromes to characterization of BM involvement in nonhematologic neoplasms. Although subtyping of NHL in the BM is more difficult from the point of morphology, classification of the entities that frequently involve the BM, especially the small B-cell lymphomas, can easily be achieved with the help of immunohistochemistry. In this review, we try to summarize the current state of the art in BM immunohistochemistry for the diagnosis of hematologic disorders. Moreover, diagnostic algorithms and useful antibody panels are proposed for a rational and cost-effective approach.

Algorithms↗
PubMed1985

Postoperative astigmatism after central vs eccentric penetrating keratoplasties.

Six patients with markedly eccentric penetrating keratoplasties had severe corneal astigmatism (mean, 10.38 +/- 2.91 diopters). In four of these patients the flat meridian was lying in the direction of graft displacement. Laboratory experiments disclosed no statistically significant difference in diameter between the major and minor axes of the corneal buttons in the centrally and eccentrically trephined eyes and we could not elucidate the mechanism of the severe astigmatism. However, in the eccentrically trephined eyes the longer axis consistently lay in the direction of decentration whereas in the centrally trephined eyes the long axis was oriented randomly.

Astigmatism↗