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PubMed2001

Corneal triple procedure.

Corneal diseases subject to keratoplasty are often combined with a certain degree of cataract. Therefore, appropriate strategies for the management of cataract are mandatory. One strategy is a sequential procedure performing cataract surgery after keratoplasty. Though this procedure enables us to estimate IOL power accurately, there are several drawbacks including multiple procedures, slow visual rehabilitation and endothelial damage during cataract surgery. On the other hand, triple procedure, consisting of penetrating keratoplasty, extracapsular lens extraction and IOL implantation, has several advantages, such as single procedure, rapid visual rehabilitation and no additional endothelial trauma. How-ever, open sky procedure may be accompanied by uncontrollable vitreous pressure followed by posterior capsule rupture and difficulty of IOL implantation, while the worst outcome may be expulsive hemorrhage. Combined core vitrectomy preceding corneal trephination is contrived to solve this problem. This procedure is simply performed from a single sclerotomy 3.5-4.01 mm posterior to the corneal limbus with a vitreous cutter under the external pressure to the eye, and vitreous pressure is sufficiently lowered to allow the following procedures to be done very safely. Another problem with triple procedure is the calculation of IOL power. This problem is caused by unpredictable keratometer readings after keratoplasty. Several methods for calculating IOL power in triple procedure are also discussed.

Cataract Extraction↗
PubMed2002

Bone marrow extracellular large geometric crystals in IgG/lambda MGUS.

We describe the peculiar histopathology of the bone marrow in a case of IgG/lambda MGUS. Striking eosinophilic crystals with a rectangular, rhomboid or square shape lay in the interstitium, sometimes in optically empty spaces, but failed to elicit a foreign body giant cell reaction. Their histochemical properties, immunoreactivity for anti-lambda light chain antiserum, and ultrastructural features strongly supported their relationship with the paraprotein synthesized by the monoclonal plasma cells. The crystals were not observed on bone marrow aspirate smear, suggesting that they had formed during trephine biopsy processing or, alternatively, that they had been removed during the smear preparation. We feel that pathologists should be aware of the existence of this type of crystals, which differ from both the amyloid deposits and the proteinaceous material sometimes observed in plasma cell proliferations. Their presence in the bone marrow should alert the clinician to investigate the involvement of other organs with immunoglobulin deposits.

Aged↗
PubMed2001

Polycythemia rubra vera versus secondary polycythemias. A clinicopathological evaluation of distinctive features in 199 patients.

To determine parameters of distinctive value in polycythemia rubra vera (PV) versus secondary polycythemias (SP), a clinicopathological study was performed on 199 patients. These presented with a borderline to marked elevation of the hemoglobin level (> 18 g/dl in men and > 16 g/dl in women). Evaluations of clinical features and bone marrow histopathology were carried out independently. According to the results derived from laboratory data and representative pretreatment trephine biopsies, three groups of patients emerged: group I presenting with the concordant clinical and morphological findings of early to manifest PV (136 patients), group II consisting of 55 patients with the congruent signs and symptoms of SP mostly caused by various chronic bronchopulmonal disorders, and finally eight patients (group III) with divergent findings. Between group I and II patients (PV versus SP), a number of clinical parameters proved to be significantly different. With the exception, of the red cell mass, platelet count, leukocyte alkaline phosphatase, LDH, spleen size, and the erythropoietin level had a significantly discriminating impact. Morphological features of distinctive value consisted of a set of specific lesions. Contrasting SP with an only borderline to slight increase in cellularity associated with a moderate enlargement of the erythroblastic islets, PV was always characterized by a significant increase in hematopoiesis, revealing a trilinear proliferation (panmyelosis). Megakaryopoiesis was strikingly different in PV as compared to SP by displaying clustering and a pleomorphous appearance. i.e., very small and giant megakaryocytes with staghorn-like nuclei were neighboring each other. Moreover, conspicuous alterations of the interstitial compartment were recognizable in SP. These consisted of deposits of cell debris in histiocytic reticular cells, iron-laden macrophages, and a plasmacytosis, implying an inflammatory reaction. These changes were only very rarely observed in PV, as opposed to a minimal to slight increase in reticulin fibers in about 12% of patients. In conclusion, a more elaborate evaluation of bone marrow features resulted in a set of diagnostic criteria with discriminating capacity that should be considered in prospective clinical trials.

Bone Marrow↗
PubMed2000

Measurement of bone metal contact (BMC) in retrieved maxillofacial osseointegrated implants.

Eighteen screw-shaped extraoral osseointegrated implants retrieved from 10 patients were analysed by microradiography. Retrieved implants were trephined with a border of surrounding bone, fixed, embedded in epon plastic, ground and processed for microradiography. The reasons for retrieval were unexplained pain (n = 4), inability to cope with the implants (n = 2), fracture of central screw (n = 2), skin penetration problems (n = 1) and trauma (n = 1). The study group comprised six males and four females with a mean age of 53.4 years (range: 9-81 years). All implants were clinically stable at the time of removal, and mean osseointegration time was 3 years (range: 1-5 years). Six implants were removed from the temporal bone, five from the frontal bone and seven from the maxilla. Bone metal contact was estimated to vary between 27% and 83%. Bone metal contact was lower in the frontal bone compared to the temporal bone or maxilla, and was further reduced after preoperative irradiation. Longer osseointegration time increased bone metal contact, as did increased age up to 60 years. It is concluded that extraoral osseointegrated implants in humans may integrate morphologically as well as clinically. By microradiography it was possible to define bone metal contact in the region of implant installation.

Adolescent↗
PubMed1998

Non-malignant bone marrow necrosis: a report of two cases.

We present two cases of bone marrow necrosis not associated with malignancy, infection or sickle cell disease. The first case, a 28 year old woman with the antiphospholipid syndrome and a factor V Leiden abnormality, suffered an illness characterised by multiple organ thromboses, anemia and refractory thrombocytopenia. She had documented bone marrow necrosis of the posterior iliac spine and numerous hot spots on bone scanning suggestive of widespread marrow necrosis. This patient also suffered hepatic infarcts and a miscarriage and may represent an explanation for the previously described "catastrophic antiphospholipid syndrome". The second patient developed widespread bone pain over a three week period, underwent a cholecystectomy and suffered major post-operative complications including a delayed transfusion reaction and disseminated intravascular coagulation. Pancytopenia developed and bone marrow trephines from numerous foci revealed widespread bone marrow necrosis. The only predisposing factor to account for this presentation was that the patient had been sniffing glue for two months prior to the illness, as the foci of necrosis had healed on repeat marrow examination eight weeks later when the patient had abstained from glue sniffing. This case may represent a reversible, toxic cause of bone marrow necrosis.

Adult↗
PubMed1997

Post-cranioplasty cerebrospinal fluid hydrodynamic changes: magnetic resonance imaging quantitative analysis.

The syndrome of the trephined has been described in many patients with cranial defects as an indication for cranioplasty. Cerebral blood flow changes, the effect of the atmospheric pressure on the brain, as well as cerebrospinal fluid hydrodynamic changes have been postulated as the possible reasons for this syndrome. Using dynamic phase-contrast magnetic resonance imaging we measured arterial, venous, and cerebrospinal fluid flow into and out of the skull, before and after cranioplasty in one patient whose bone flap was removed because of osteomyelitis. We report significant changes in the oscillatory CSF flow after cranioplasty. A moderate increase in venous outflow as well as a two-fold increase in craniocaudal cerebrospinal fluid systolic flow velocity was measured after the skull closure. The changes in the cerebrospinal fluid oscillatory flow at the level of the craniovertebral junction could reflect changes in the compliance of the craniospinal system produced by closure of the cranial defect.

Adult↗
PubMed1999

New device to treat chronic subdural hematoma--hollow screw.

Different surgical approaches exist for the treatment of chronic subdural hematoma. None of these approaches is superior to the other, so a minimal-invasive device (a hollow screw) was developed. The system consists of a stable hollow screw of surgical steel with a perforated tip, a hand-drill, screwdriver with guide, and collection bag. To place the screw in the skull local anesthesia is necessary followed by stab incision and percutaneous trephination. The screw is then placed in the bone and the guide removed. After spontaneous drainage and irrigation, a closed drainage system with a collection bag is connected with the screw. First results with the new technology are promising, with a high rate of completely treated patients and a low rate of complications. Two of 86 patients had a local skin infection after implantation of the screw, and in 22 patients the procedure was repeated due to one or more cases of recurrent or residual hematoma. No neurological deterioration was caused by the screw or the surgical approach. The advantages of this new system are: quick and simple procedure, minimal invasive, excellent function, inexpensive and reusable.

Adolescent↗
PubMed2004

Increased resistance of crosslinked cornea against enzymatic digestion.

PURPOSE: Collagen-crosslinking using combined riboflavin/ UVA treatment has been developed by us as a new treatment for keratoconus by stiffening the collagenous matrix. Recently, we have started to use the same method for the treatment of corneal ulcers. The aim of the present study was to evaluate the influence of the crosslinking treatment on the resistance of the cornea against enzymatic degradation. METHODS: 60 enucleated porcine eyes were treated with the photosensitizer riboflavin and UVA-irradiation (370 nm; irradiance of 1, 2 or 3 mW/cm2) for 30 minutes and compared with 20 untreated control eyes. After crosslinking treatment, the corneal buttons were trephined and exposed to pepsin, trypsin and collagenase solutions. The extent of the corneal digestion was monitored daily. Selected cases were examined by light microscopy. RESULTS: The corneal buttons crosslinked with riboflavin/ UVA at 3 mW/cm2 were dissolved only by day 13 following pepsin digestion and by day 14 following collagenase treatment versus 6 days in the untreated control corneas. Digestion by trypsin was observed on day 5 in buttons crosslinked at 3 mW/cm2 compared to day 2 in the control corneas. Microscopically, a prolonged preservation especially of the anterior portion of the crosslinked corneas could be demonstrated. CONCLUSIONS: Photochemical crosslinking of the cornea using riboflavin and UVA results in a markedly increased resistance versus collagen digesting enzymes. The findings support the use of the new method in the treatment of corneal ulcers.

Animals↗
PubMed2004

Bone marrow mastocytosis associated with IgM kappa plasma cell myeloma.

An association between mastocytosis and monoclonal gammopathy is a relatively rare but well recognized clinical finding. In the majority of cases, however, overt myeloma or lymphoma is not detectable morphologically. Here we describe the case of a 51 year-old male patient first presenting with paresis of the right facial nerve and the serological finding of IgM kappa paraproteinemia. The patient did not have organomegaly, lytic bone lesions, or urticaria pigmentosa-type skin lesions. Histological examination of a trephine biopsy specimen revealed the unusual coexistence of plasma cell myeloma and mastocytosis. Immunohistochemically, plasma cells were found to exhibit a monotypic staining for Ig heavy chain mu and Ig light chain kappa, thus confirming their neoplastic nature. Mast cells showed prominent spindling and formed dense multifocal infiltrates, thus enabling the diagnosis of bone marrow mastocytosis. Immunohistochemically, mast cells expressed tryptase, chymase, and KIT (CD117). In addition, aberrant expression of CD25 on mast cells was detected, confirming the coexistence of a neoplastic mast cell-proliferative disorder. According to the WHO proposal for classification of hematopoietic malignancies, this unique case, showing the association of two very rare haematologic neoplasms, can therefore best be referred to as bone marrow mastocytosis associated with IgM kappa plasma cell myeloma (SM-AHNMD).

Antigens, CD↗
PubMed2004

The prognostic value of CD38 expression and its quantification in B cell chronic lymphocytic leukemia (B-CLL).

A large number of prognostic factors are available to help predict the outcome of patients who present with B-cell chronic lymphocytic leukemia (B-CLL). These include clinical stage, leukemic cell morphology, lymphocyte doubling time, the pattern of infiltration in bone marrow trephine biopsies, cytogenetic abnormalities, p53 function and serum factors such as beta-2 microglobulin. Two recently described major prognostic factors are immunoglobulin heavy chain variable region (IgVH) mutation status and cell membrane expression of CD38. These are both highly significant independent prognostic factors, but are not closely correlated. Whereas IgVH mutational status is a time consuming and demanding technique, only available in a limited number of centres, CD38 expression by flow cytometry is relatively simple and rapidly obtained in most diagnostic laboratories. The predictive value of CD38 expression is enhanced by measurement of antigen density in terms of antibody binding capacity (ABC) rather than as the percentage of cells expressing the antigen. ABC correlates closely with relative median fluorescence (RMF), a parameter which is even more simply and cheaply obtained by flow cytometry. One of these methods of determining CD38 expression should be employed routinely. Recent work suggests that membrane ZAP-70 expression determined by flow cytometry will prove to be an accurate proxy for IgVH mutational status and this assay will be within the reach of any laboratory skilled in flow cytometry. The combination of ZAP-70 expression, CD38 antigen density, p53 function and the concentration of serum factors such as soluble CD23, is likely to provide extremely accurate prognostic information in future studies. This will assist in identifying Stage A patients who may benfit from early and/or more intensive treatment, as well as Stage B and C patients who may require alternative treatment strategies at the outset.

ADP-ribosyl Cyclase↗
PubMed2005

Bone marrow CD34+ progenitor cells in Philadelphia chromosome-negative chronic myeloproliferative disorders--a clinicopathological study on 575 patients.

Contrasting the circulating CD34+ hematopoietic progenitor cells (HPCs) in chronic myeloproliferative disorders (CMPDs), scant knowledge is available regarding their quantity in the bone marrow (BM). Therefore, a clinicopathological study was performed on trephine biopsies in 575 patients with CMPDs focused on chronic idiopathic myelofibrosis (CIMF). A comparison with 25 healthy subjects revealed no significant differences in the numbers of HPCs (6 +/- 3/mm2) in polycythemia vera, essential thrombocythemia and advanced fibro-osteosclerotic stages of CIMF. Pre-fibrotic and early-stage CIMF displayed 16 +/- 11 precursors per mm2 BM. Sequential biopsies in this disorder showed a decline in HPCs (10 +/- 6/mm2) with evolving myelofibrosis-myeloid metaplasia (MMM), while in terminal stages acceleration generated an increase (24 +/- 25/mm2). A significant association between the quantity of HPCs and the development of myelofibrosis, splenomegaly, and anemia as well as an increase in peripheral blasts was recognizable in CIMF. Moreover, in all subtypes of CMPDs, a favorable prognosis was significantly associated with a higher number of HPCs in the BM. In conclusion, enhanced inflow of precursors from the BM with subsequent trapping, self-renewal and mobilization by the spleen is assumed to indicate a progressive generalization and worsening of the outcome. This putative pathomechanism is significantly associated with the evolution of MMM.

Antigens, CD34↗
PubMed1999

Laser shaping of corneal transplants in vitro: area ablation with small overlapping laser spots produced by a pulsed scanning laser beam using an optimizing ablation algorithm.

Area laser lathing and trephination of donor corneas is used to produce different types of grafts for human transplantation. 193 nm (ArF excimer) laser radiation is used, since this is known to give a non-thermal laser-tissue interaction with a minimal zone of tissue damage. To guarantee the highest degree of flexibility concerning the overall shape of the grafts as well as their thickness profiles, we use a small (compared with the area to be ablated) scanning laser spot. For area lathing of the tissue we have developed a new ablation algorithm (optimized scanning laser ablation, OSLA) that can be applied to lathe and perforate any tissue--with concave (as in this application), convex or plane surface geometry--where surface precision and smoothness are key issues. Using OSLA with the Excimer Laser Corneal Shaping System (a tool for in vitro fabrication of all kinds of corneal transplants like donor buttons for keratoplasty, lamellar grafts for epikeratoplasty and refractive lenticules) enabled us to produce all types of corneal grafts with very high precision. This is considered to be a major improvement towards the production of refractive lenticules.

Algorithms↗
PubMed1989

Topical ocular anesthetics affect epithelial cytoskeletal proteins of wounded cornea.

The purpose of this study was to characterize by immunofluorescent microscopy, the cytoskeletal proteins actin and myosin and the protein calmodulin (CaM) in trephined, n-heptanol treated murine corneal epithelium during in vitro organ culture before and following topical ocular anesthetic application. The study has shown that corneal epithelial wounds exposed to anesthetic agents fail to close, even after 24 hr of culture. Failure of the wound to close was accompanied by a general decrease in immunofluorescence for actin myosin and CaM following application of the anesthetics.

Actins↗
PubMed2005

Physicochemical properties and in vivo assessment of timolol-loaded poly(D,L-lactide-co-glycolide) films for long-term intraocular pressure lowering effects.

Timolol-loaded poly(D,L-lactide-co-glycolide; PLGA) films were prepared for achieving the long-term intraocular pressure (IOP) lowering effect on glaucoma treatment. The physicochemical properties and in vivo effects of films were determined and characterize the delivery system. PLGA, span 20, propylene glycol (PG), and timolol base were dissolved in dichloromethane (DCM) and kept in a stainless mold; timolol films were prepared after the evaporation of DCM. Timolol disc-shape film preparation (TDF), containing 1 mg of timolol in 0.37 cm(2) area, was fabricated by using a trephine and placed onto the cul de sac of alpha-chymotrypsin-induced ocular hypertension rabbits for assessing the IOP lowering effect. The prepared films characterized a Young's modulus ranged from 1.13 to approximately 2.49 MPa, and related to the content percentages of PLGA, PG, and the residual DCM. The timolol film could maintain drug release for 1 week. Following a single-dose application in ocular hypertension rabbits, the prepared TDF could achieve a long-term IOP lowering effect and maintain the IOP change (in comparison with baseline) of approximately 7 mmHg within 1 week. The aqueous humor levels of timolol were low within a range of 0.8 to approximately 0.24 microg/mL for the initial 24 h and less than 0.15 microg/mL for 4-7 days. The investigated film formulation might be potentially developed for the application of long-term ocular delivery systems.

Adrenergic beta-Antagonists↗
PubMed1991

Laparoscopic lumbar discectomy: case report.

Laparoscopic lumbar discectomy is an extension of two accepted technologies, laparoscopy and percutaneous discectomy. A young male with an L5-S1 disc herniation had the anterior aspect of the lumbosacral disc exposed laparoscopically. The disc space was entered with a trephine under fluoroscopic and video control. The discectomy was carried out with curettes and rongeurs. Evoked potentials monitored continuously, reverted to normal with decompression of the S1 nerve root. This was accomplished in an outpatient setting with minimal use of oral narcotics.

Adult↗
PubMed1993

Osteitis fibrosa cystica simulating metastatic tumor. An almost-forgotten relationship.

The diagnosis of primary hyperparathyroidism most often results from the incidental finding of hypercalcemia. In two recent cases of osteitis fibrosa cystica (OFC), however, patients without adequate access to health care served as graphic reminders that the clinical spectrum of the disease includes bone disease, and that OFC can be the presenting manifestation of long-standing primary hyperparathyroidism. Both patients complained of bone pain and had widespread osteolytic bone lesions in addition to hypercalcemia on a multitest biochemical panel. The presumptive diagnosis of malignancy with bone involvement (metastatic cancer or multiple myeloma) led to random bone marrow trephine biopsies. Examination of the bone marrow biopsy material revealed the characteristic pathology of OFC, leading to appropriate diagnosis and surgical management of large parathyroid adenomas in both patients.

Adult↗
PubMed1994

CD34 immunostaining of bone marrow biopsy specimens is a reliable way to classify the phases of chronic myeloid leukemia.

Flow cytometry studies have shown that high expression of CD34 antigen in patients with chronic myeloid leukemia (CML) is indicative of accelerated or blastic phases. It has also been suggested that similar information can be obtained by CD34 immunostaining of bone marrow biopsy specimens. To test this hypothesis, the authors studied 59 conventionally fixed, paraffin-embedded bone marrow trephine biopsy specimens, representing the three phases of the disease (stable, accelerated, and blast crisis). Immunohistochemical staining for CD34 was performed using QBEnd10, a monoclonal antibody reactive in routine paraffin-embedded tissue. The differences in CD34 positivity among chronic, accelerated, and blastic phases of CML were highly significant (P = .0001). This study demonstrated that CD34 immunohistochemical staining of bone marrow biopsy specimens represents a reliable method for classifying patients with CML and may provide essential diagnostic and prognostic information when a marrow aspirate is unavailable.

Antigens, CD↗
PubMed1994

Detection of monoclonal B-cell populations in decalcified, plastic-embedded bone marrow biopsies with the polymerase chain reaction.

Polymerase chain reaction (PCR) has been employed successfully for the detection of clonal immunoglobulin gene rearrangements in paraffin-embedded clinical samples. The authors examined whether this technique can also be applied to fixed, decalcified, and plastic-embedded bone marrow biopsies. DNA extracted from 66 glycolmethacrylate-embedded trephine biopsy samples was amplified for the detection of rearranged VDJ regions of the immunoglobulin heavy chain genes using both a single-step and a semi-nested PCR technique. After exclusion of samples with inadequate DNA, clonality was confirmed in 16 (67%) of 24 cases with B cell malignancy, whereas all 11 non-B cell neoplasms, and 6 of 9 cases with normal bone marrow showed evidence of a polyclonal B cell population. Patterns indicating oligo- or monoclonality were observed in three plastic-embedded samples of normal bone marrow, although control PCR of frozen bone marrow samples obtained in parallel showed no evidence of clonality. Repeated PCR of these cases revealed inconsistent bands, probably due to the amplification of rare templates from polyclonal B cells. Decalcified, plastic-embedded bone marrow biopsies are suitable for PCR-based determination of B-cell clonality. To exclude the possibility of false-positive results, monitoring of template DNA quality and independent control amplifications are mandatory.

B-Lymphocytes↗