Biochemische Knochenmarker und deren Bedeutung bei der postmenopausalen Osteoporose – Eine neue Methode in der Osteoporosediagnostik? / Biochemical Markers and their Significance in Postmenopausal Osteoporosis – A new Method in the Diagnosis of Osteoporosis?

This study analyzes the qualification of biochemical markers in the diagnosis of osteoporosis and evaluates the potential of a multiparametric classification of premenopausal and non-osteoporotic as well as osteoporotic postmenopausal women, which is based on biochemical marker profiles. For this evaluation data of 29 women in the age between 28-74 years were used. The classification of osteoporosis was done by the trabecular density of the lumbar spine using qCT-measurements. The biochemical markers of formation and resorption AP, bAP, OC, ucOC, PICP, PYD, DPD, NTX, BSP and vitamin K were analyzed on day 1 and 42 in all patients. For vitamin K we found significant distribution differences between non-osteoporotic and osteoporotic women (p<0.005). The crosslinks PYD and DPD showed weakly significant differences. All other parameters exhibited non-significant results. Vitamin K acted with a sensitivity of 64% and a specificity of 82%. The used multiparameter classification process improved sensitivity and specificity considerably. The parameter profiles of OC/PYD, vitamin K/PYD and vitamin K/bAP revealed the highest sensitivities with specificities of more than 82%.

Value of micro-CT as an investigative tool for osteochondritis dissecans

PURPOSE

To evaluate micro computed tomography (micro-CT) for the assessment of osteochondritis dissecans in comparison with histology.

MATERIAL AND METHODS

Osteochondritis dissecans lesions of 3 patients were evaluated using micro-CT (0.125 mA, 40 keV, 60 microm slice thickness, 60 microm isotropic resolution, entire sample) and light microscopy (toluidine blue, 3-5 microm slice thickness). The methods were compared regarding preparation time, detectability of tissue types and morphologic features of bone and cartilage.

RESULTS

Non-destructive micro-CT imaging of the entire sample was faster than histologic preparation of a single slice for light microscopy. Morphologic features of bone and cartilage could be imaged in a comparable way to histology. It was not possible to image cells or different tissue types of bone and cartilage with micro-CT.

CONCLUSION

Micro-CT is a fast, non-destructive tool that may be a supplement or, if detailed histologic information is not necessary, an alternative to light microscopy for the investigation of osteochondritis dissecans.

[Radiology in managed care environment: opportunities for cost savings in an HMO]

PURPOSE

A large regional health plan in the Northeastern United States noted that its radiology costs were increasing more than it anticipated in its pricing, and noted further that other similar health plans in markets with high managed care penetration had significantly lower expenses for radiology services. This study describes the potential areas of improvement and managed care techniques that were implemented to reduce costs and reform processes.

MATERIALS AND METHODS

We performed an in-depth analysis of financial data, claims logic, contracting with provider units and conducted interviews with employees, to identify potential areas of improvement and cost reduction. A detailed market analysis of the environment, competitors and vendors was accompanied by extensive literature, Internet and Medline search for comparable projects. All data were docu-mented in Microsoft Excel(R) and analyzed by non-parametric tests using SPSS(R) 8.0 (Statistical Package for the Social Sciences) for Windows(R).

RESULTS

The main factors driving the cost increases in radiology were divided into those internal or external to the HMO. Among the internal factors, the claims logic was allowing overpayment due to limitations of the IT system. Risk arrangements between insurer and provider units (PU) as well as the extent of provider unit management and administration showed a significant correlation with financial performance in terms of variance from budget. Among the external factors, shared risk arrangements between HMO and provider unit were associated with more efficient radiology utilization and overall improvement in financial performance. PU with full-time management had significantly less variance from their budget than those without. Finally, physicians with imaging equipment in their offices ordered up to 4 to 5 times more imaging procedures than physicians who did not perform imaging studies themselves.

CONCLUSION

We identified initiatives with estimated potential savings of approximately $ 5.5 million. Some of these initiatives are similar to the reforms to reduce cost and improve quality that are already implemented or proposed within the German healthcare system.

Selective water excitation for faster MR imaging of articular cartilage defects: initial clinical results

Our objective was to compare a water-excitation (WE) 3D fast low-angle shot (FLASH) MR sequence for faster imaging of articular cartilage defects of the knee to a conventional fat-saturated (FS) 3D FLASH MR sequence. This prospective study included 16 knees of 16 patients with suspected cartilage lesions. The MR imaging in transverse and sagittal planes included (a) FS 3D FLASH (TR/TE: 45 ms/11 ms, scan time 8 min, flip angle 50 degrees), and (b) WE 3D FLASH (TR/TE: 28 ms/11 ms, scan time 4 min 58 s, flip angle 40 degrees). For each sequence signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were quantified. The detected cartilage lesions were evaluated using a semi-quantitative four-scale scoring system (grades 0-III). The data were compared between the sequences using the paired Student's t-test. No statistically significant differences between the sequences were found for SNR, CNR, and cartilage defect grading (p=0.14-0.8). The WE 3D FLASH MR imaging seems to be promising for fast imaging of articular cartilage lesions of the knee.

Gadobutrol: an alternative contrast agent for digital subtraction dacryocystography

We report the application of gadobutrol as a contrast medium for digital subtraction dacryocystography (DS-DCG) in patients with known allergy to iodinated contrast agent. Gadobutrol has the double gadolinium concentration (1.0 mmol/ml) of other gadolinium-based contrast agents. Quality of the DS-DCG images obtained with gadobutrol was comparable to DS-DCG images obtained with iodinated contrast medium. Radiodensity measurements using a micro-CT scanner confirmed a high radiodensity of gadobutrol which was comparable to the radiodensity of iopentol with a iodine concentration of 250 mg/ml and only approximately 20% lower than the radiodensity of iopentol with a concentration of 300 mg/l. Gadobutrol is a well-suited substitute for DS-DCG in patients with allergy to iodinated contrast agents.

[Retropupillary fixation of the iris claw lens in aphakia. 1 year outcome of a new implantation techniques]

INTRODUCTION

There are several surgical options available for the correction of aphakia. We investigated if retropupillary fixation of an iris claw lens is a method combining the advantages of posterior chamber implants with a new low-risk method of intervention.

PATIENTS AND METHODS

An iris claw lens was implanted in 48 eyes in the plano-convex direction (model 205 Y). For the calculation of the IOL power we estimated an A-constant of 116.8. The lens was pushed via a 5-mm wide corneal incision vertically in the anterior chamber and was fixed in the retropupillary position after turning in the horizontal direction. After aspiration of the viscoelastica the corneal incision was closed by a 10-0 nylon suture.

RESULTS

The implantation was successful in all patients. A visual improvement was noted in 27 patients (56.2%), an unchanged visual acuity was seen in 18 patients (37.5%) while 3 patients (6.2%) showed a loss of visual acuity. A cystoid macular edema was found by fluorescein angiography in two cases. Leakages in the area of the enclavation were not seen.

SUMMARY

The retropupillary fixation of an iris claw lens seems to have the advantages of a true posterior chamber implantation with a low intra- and postoperative risk profile. The easy implantation process with this technique could replace the normally applied sclera suture fixed implantation of a posterior chamber lens as the method of choice.

[Functional magnetic resonance imaging: Physiological background, technical aspects and prerequisites for clinical use]

The advent of powerful gradient systems and ultrafast echo-planar imaging (EPI) offers the opportunity to use magnetic resonance imaging to measure and to localize brain function with high spatio-temporal resolution in clinically feasible scanning times. Functional magnetic resonance imaging (fMRI) opens up a new diagnostic field in radiology and neuroradiology with a change from pure morphological brain imaging to the measurement and visualization of brain function. Despite its successful application in neurosurgical, neurological, psychiatric, neuropediatric and pain patients fMRI has not yet reached the status of an established clinical diagnostic procedure. To this end special stimulation systems, standardized fMRI protocols and medically approved software, all dedicated to clinical application, are necessary. The training and teaching of doctors and radiographers will also be crucial for the progress of clinical fMRI. This paper gives an overview of the neurophysiological background, the technical requirements and the data processing strategies that are relevant for the clinical application of fMRI. Presurgical fMRI in patients with brain tumors is used as an example for the clinical relevance of the method.

[Value of MRI in intracerebral and subarachnoid hemorrhage]

Intracranial hemorrhage (ICH) accounts for 15% of all strokes. In hyperacute emergency assessment, CT is the diagnostic standard for differentiating between hyperacute ICH and ischemic stroke. At this stage, MRI is considered to be of little value for the diagnosis of ICH or subarachnoidal hemorrhage (SAH). We review the current literature and characterize the role of MRI in the diagnosis of ICH and SAH as well as hyperacute stroke in general: While MRI is considered superior to CT in the diagnosis of subacute and chronic ICH/SAH, in hyperacute ICH this is still a matter of debate. MRI signal characteristics of ICH depend on hemoglobin degradation. Deoxyhemoglobin is the MRI substrate for demonstration of blood due to its paramagnetic properties causing signal loss on susceptibility weighted images (T2*-WI). Preliminary data, however, suggest that the sensitivity of modern stroke MRI protocols is sufficiently high for hyperacute ICH and SAH and may render additional information with regard to the etiology of ICH or SAH. Further interest is focused on perihemorrhagic pathophysiologic processes, which may help to improve therapeutic decision making in patients with ICH.

Thrombolytic therapy for ischemic stroke--a review. Part II--Intra-arterial thrombolysis, vertebrobasilar stroke, phase IV trials, and stroke imaging

OBJECTIVE

Intra-arterial thrombolytic therapy for carotid and vertebrobasilar stroke may result in a more rapid clot lysis and higher recanalization rates than can be achieved with intravenous thrombolysis and thus may warrant the more invasive and time-consuming therapeutic approach. We present an overview of all hitherto completed trials of intra-arterial thrombolytic therapy for carotid and vertebrobasilar artery stroke including recommendations for therapy and a meta-analysis. Furthermore, new imaging techniques such as diffusion- and perfusion-weighted magnetic resonance imaging and their impact on patient selection are discussed. Finally, phase IV trials of thrombolysis in general and cost efficacy analyses are presented.

DATA SOURCES

We performed an extensive literature search not only to identify the larger and well-known randomized trials but also to identify smaller pilot studies and case series. Trials included in this review, among others, are the PROACT I and PROACT II studies and the Cochrane Library report.

CONCLUSION

Intra-arterial thrombolytic therapy of acute M1 and M2 occlusions with 9 mg/2 hrs pro-urokinase significantly improves outcome if administered within 6 hrs after stroke onset. Seven patients need to be treated to prevent one patient from death or dependence. Vertebrobasilar occlusion has a grim prognosis and intra-arterial thrombolytic therapy to date is the only life-saving therapy that has demonstrated benefit with regard to mortality and outcome, albeit not in a randomized trial. New magnetic resonance imaging techniques may facilitate and improve the selection of patients for thrombolytic therapy. Presently, thrombolytic therapy is still underutilized because of problems with clinical and time criteria, and lack of public and professional education to regard stroke as a treatable emergency. If applied more widely, thrombolytic therapy may result in profound cost savings in health care and reduction of long-term disability of stroke patients.

Thrombolytic therapy for ischemic stroke--a review. Part I--Intravenous thrombolysis

OBJECTIVE

Thrombolytic therapy for acute ischemic stroke was implemented into clinical routine 4 yrs ago. Unfortunately, at present <2% of eligible patients receive thrombolytic therapy. We present an overview of all hitherto completed trials of intravenous thrombolytic therapy for carotid artery stroke including recommendations for therapy and diagnostic procedures and their impact on patient selection and meta-analyses.

DATA SOURCES

We performed an extensive literature search not only to identify the larger and well-known randomized trials but also to identify smaller pilot studies and case series. Trials included in this review, among others, are the National Institute of Neurologic Disorders and Stroke (NINDS) study, European Cooperative Acute Stroke Study I and II, and Alteplase Thrombolysis for Acute Noninterventional Therapy in Ischemic Stroke (ATLANTIS) A and B and two large meta-analyses, including the Cochrane Library report.

CONCLUSION

Intravenous thrombolytic therapy with recombinant tissue plasminogen activator has demonstrated a significant benefit and has proven to be safe for patients who can be treated within 3-6 hrs after symptom onset. This benefit is at the cost of an increased rate of symptomatic intracranial hemorrhage without a significant effect on overall mortality. In general, the benefit of thrombolysis decreases and the risks increase with progressing time after symptom onset. Presently, thrombolytic therapy is still underutilized because of problems with clinical and time criteria, and lack of public and professional education to regard stroke as a treatable emergency. If applied more widely, thrombolytic therapy may result in profound cost savings in health care and reduction of long-term disability of stroke patients.

Acute disseminated encephalomyelitis: a follow-up study of 40 adult patients

OBJECTIVES

To describe the clinical, CSF, and radiologic findings and long-term follow-up in a cohort of patients with acute disseminated encephalomyelitis (ADEM), and to determine possible prognostic factors for progression to MS.

METHODS

Forty adults (28 women, mean age 33.5 years) diagnosed with ADEM were analyzed. Clinical symptoms, cranial MRI and CSF findings, and the response to a standardized treatment during the acute phase of the disease were analyzed by chart review. The final diagnosis of ADEM or clinically definite MS was established upon follow-up examination after 8 to 137 months. The patients with ADEM and MS were compared to detect differences between the two groups.

RESULTS

Fifteen patients had a preceding infection (n = 14) or immunization (n = 1). The most frequent clinical signs were motor deficit (80%), followed by sensory deficits, brainstem signs, and ataxia. CSF findings were highly variable; normal results were present in 20% of patients. Oligoclonal bands were positive in 65% of patients. Ninety-five percent of all patients improved during the acute phase of the disease. Upon follow-up, 14 patients had developed clinically definite MS. Of the 26 patients with the final diagnosis of ADEM, two patients had died, nine had minor deficits, three had moderate deficits, and 12 patients had no remaining symptoms. Patients with the final diagnosis of ADEM were older, and more often had a preceding infection, clinical signs of brainstem involvement, a higher CSF albumin fraction, and infratentorial lesions.

CONCLUSIONS

Many patients initially diagnosed with ADEM develop clinically definite MS upon long-term follow-up. The authors found no useful diagnostic criteria for the differentiation of a first episode of MS from monophasic ADEM. The term ADEM may still be employed as a description of a clinical syndrome, but should not be used as a distinct entity until reliable diagnostic criteria have been developed.

[Similarity of the brains of twins]

PURPOSE

To test the assumption underlying every morphometric twin study that the brains of monozygotic twins are almost identical.

METHODS

High resolution MRI of the neurocranium of 26 monozygotic twin pairs were acquired and the volumes of 36 cerebral structures were measured. The same twins served as control group after rear-ranging them into non-related pairs of same sex and matching them for age, body height and body weight.

RESULTS

For most of the examined structures the correlations within the twins were significant (R = 0.97-0.59). Except for total forebrain volume the controls showed no significant similarity.

CONCLUSIONS

For almost every measured cerebral structure the assumption, that significant similarities exist between healthy monozygotic twins is correct. Therefore discordant monozygotic twins represent an excellent sample when investigating cerebral correlates of neurologic and psychiatric disorders.

Acute disseminated encephalomyelitis: a follow-up study of 40 adult patients

OBJECTIVES

To describe the clinical, CSF, and radiologic findings and long-term follow-up in a cohort of patients with acute disseminated encephalomyelitis (ADEM), and to determine possible prognostic factors for progression to MS.

METHODS

Forty adults (28 women, mean age 33.5 years) diagnosed with ADEM were analyzed. Clinical symptoms, cranial MRI and CSF findings, and the response to a standardized treatment during the acute phase of the disease were analyzed by chart review. The final diagnosis of ADEM or clinically definite MS was established upon follow-up examination after 8 to 137 months. The patients with ADEM and MS were compared to detect differences between the two groups.

RESULTS

Fifteen patients had a preceding infection (n = 14) or immunization (n = 1). The most frequent clinical signs were motor deficit (80%), followed by sensory deficits, brainstem signs, and ataxia. CSF findings were highly variable; normal results were present in 20% of patients. Oligoclonal bands were positive in 65% of patients. Ninety-five percent of all patients improved during the acute phase of the disease. Upon follow-up, 14 patients had developed clinically definite MS. Of the 26 patients with the final diagnosis of ADEM, two patients had died, nine had minor deficits, three had moderate deficits, and 12 patients had no remaining symptoms. Patients with the final diagnosis of ADEM were older, and more often had a preceding infection, clinical signs of brainstem involvement, a higher CSF albumin fraction, and infratentorial lesions.

CONCLUSIONS

Many patients initially diagnosed with ADEM develop clinically definite MS upon long-term follow-up. The authors found no useful diagnostic criteria for the differentiation of a first episode of MS from monophasic ADEM. The term ADEM may still be employed as a description of a clinical syndrome, but should not be used as a distinct entity until reliable diagnostic criteria have been developed.

Respiratory syncytial virus infection in the late bone marrow transplant period: report of three cases and review

Respiratory syncytial virus (RSV) infection is an important cause of respiratory mortality in immunosuppressed patients, including bone marrow transplant (BMT) recipients. The presence of lower respiratory tract infection and infection in the pre-engraftment phase of BMT is believed to confer a poor prognosis. Three patients who underwent allogeneic BMT at our institution developed RSV pneumonia over 1 year post BMT, with the underlying disease in remission. All three were hypoxic with extensive pulmonary disease at presentation. Treatment consisted of aerosolized ribavirin and intravenous immune globulin with successful clearing of viral shedding and excellent clinical outcomes. RSV infection is probably less severe in the late post-BMT period, but needs to be considered early in the differential diagnosis of pulmonary infiltrates in this patient population.

[Acute disseminated encephalomyelitis (ADEM)]

Acute disseminated encephalomyelitis (ADEM) is an unusual demyelinating disease of the CNS. We review clinical symptoms, findings from radiological and CSF examinations, and current treatment strategies for ADEM. This disorder is often associated with a precedent infection or vaccination but may also occur spontaneously. The clinical symptoms are highly variable. Analysis of CSF usually reveals lymphocytic pleocytosis and an elevated protein content but may also yield normal results. Magnetic resonance imaging shows solitary or multiple lesions within the CNS. Most patients improve quickly with methylprednisolone. If that fails, immunoglobulin, plasmapheresis, or cytostatic drugs can be employed. Unlike MS, ADEM has a monophasic course and favourable long-term prognosis. Multiphasic courses are very rare. There are no diagnostic criteria to distinguish ADEM reliably from MS during the acute phase. We presume that ADEM is a variant of MS and not an independent disease entity.

Stroke magnetic resonance imaging within 6 hours after onset of hyperacute cerebral ischemia

We studied the diagnostic and prognostic value of diffusion- and perfusion-weighted magnetic resonancce imaging (DWI and PWI) for the initial evaluation and follow-up monitoring of patients with stroke that had ensued less than 6 hours previously. Further, we examined the role of vessel patency or occlusion and subsequent recanalization or persistent occlusion for further clinical and morphological stroke progression so as to define categories of patients and facilitate treatment decisions. Fifty-one patients underwent stroke magnetic resonance imaging (DWI, PWI, magnetic resonance angiography, and T2-weighted imaging) within 3.3 +/- 1.29 hours, and, of those, 41 underwent follow-up magnetic resonance imaging on day 2 and 28 on day 5. In addition, we assessed clinical scores (on the National Institutes of Health Stroke Scale, Scandinavian Stroke Scale, Barthel Index, and Modified Rankin Scale) on days 1, 2, 5, 30, and 90 and performed volumetric analysis of lesion volumes. In all, 25 patients had a proximal, 18 a distal, and 8 no vessel occlusion. Furthermore, 15 of 43 patients exhibited recanalization on day 2. Vessel occlusion was associated with a PWI-DWI mismatch on the initial magnetic resonance imaging, vessel patency with a PWI-DWI match (p < 0.0001). Outcome scores and lesion volumes differed significantly between patients experiencing recanalization and those who did not (all p < 0.0001). Acute DWI and PWI lesion volumes correlated poorly with acute clinical scores and only modestly with outcome scores. We have concluded on the basis of this study that early recanalization saves tissue at risk of ischemic infarction and results in significantly smaller infarcts and a significantly better clinical outcome. Patients with proximal vessel occlusions have a larger amount of tissue at risk, a lower recanalization rate, and a worse outcome. Urgent recanalization seems to be of utmost importance for these patients.

[Combined cataract-glaucoma surgery with deep sclerectomy. An alternative to gonio-trephination in the intra- and early postoperative phases]

BACKGROUND

We examined the value of deep sclerectomy combined with phacoemulsification as a surgical technique in the peri- and postoperative phases.

MATERIALS AND METHODS

Deep sclerectomy with phacoemulsification was carried out in 18 patients. Mean postoperative follow-up was 7.5 weeks.

RESULTS

Deep sclerectomy was more difficult to perform than goniotrephination. We observed neither fibrin reaction nor hypotonic dysregulation (intraocular pressure, IOP, < 8 mmHg). Five patients required additional pressure-lowering drugs during postoperative IOP regulation.

CONCLUSION

We consider the low inflammatory response in the early postoperative phase to outweigh the greater surgical difficulty and prolonged surgery time. Further studies must verify whether higher IOP during the early postoperative phase is sufficient for good long-term IOP regulation.

Src homology 2-containing inositol 5-phosphatase 1 binds to the multifunctional docking site of c-Met and potentiates hepatocyte growth factor-induced branching tubulogenesis

Hepatocyte growth factor (HGF)/scatter factor is a multifunctional cytokine that induces mitogenesis, motility, and morphogenesis in epithelial, endothelial, and neuronal cells. The receptor for HGF/scatter factor was identified as c-Met tyrosine kinase, and activation of the receptor induces multiple signaling cascades. To gain further insight into c-Met-mediated multiple events at a molecular level, we isolated several signaling molecules including a novel binding partner of c-Met, SH2 domain-containing inositol 5-phosphatase 1 (SHIP-1). Western blot analysis revealed that SHIP-1 is expressed in the epithelial cell line, Madin-Darby canine kidney (MDCK) cells. SHIP-1 binds at phosphotyrosine 1356 at the multifunctional docking site. Because a number of signaling molecules such as Grb2, phosphatidylinositol 3-kinase, and Gab1 bind to the multifunctional docking site, we further performed an in vitro competition study using glutathione S-transferase- or His-tagged signaling molecules with c-Met tyrosine kinase. Our binding study revealed that SHIP-1, Grb2, and Gab1 bound preferentially over phosphatidylinositol 3-kinase. Surprisingly, MDCK cells that overexpress SHIP-1 demonstrated branching tubulogenesis within 2 days after HGF treatment, whereas wild-type MDCK cells showed tubulogenesis only after 6 days following treatment without altering cell scattering or cell growth potency. Furthermore, overexpression of a mutant SHIP-1 lacking catalytic activity impaired HGF-mediated branching tubulogenesis.

[Nocturnal spinal fracture--first manifestation of epilepsy]

A 54-year-old patient suffered overnight a double thoracic burst-fracture. One week later during the investigation for a metabolic or endocrinological cause, a witnessed seizure led to an unstable fracture of the humerus and the scapula. The neurological work-up revealed a cerebral astrocytoma as the epileptogenic focus. Forces generated during a tonic-clonic seizure can result in axial skeletal trauma, including thoracic and lumbar burst fractures. Vertebral fractures unrelated to an exogenous trauma are therefore always suspicious of an underlying epileptic disease.

[Value of kinematic MRI in the evaluation of patients with exacerbated pain in cervical spine motion compared with static MRI]

OBJECTIVE

To assess the clinical value of kinematic MR imaging in patients with cervical radiculopathy and increasing symptoms after provocative maneuvers at flexion, extension, axial rotation and coupled motion of the cervical spine.

METHODS

Thirty-five patients with cervical disc herniation or cervical spondylosis in whom symptoms were elicited at flexion, extension, axial rotation and coupled motion were studied inside a positioning device using T2-weighted TSE, 2D-FLASH, and reformatted 3D DESS and 3D-FISP sequences. The images were evaluated for the size of disc herniations, the foraminal size and cervical cord displacement at provocative position compared with neutral position (0 degree). In addition, the value of kinematic MR images were interpretated with regard to changes in the therapeutic procedure and intraoperative patient positioning.

RESULTS

Compared with the neutral position (0 degree) a change in disc herniations was not found in any (0%) of the provocative positions. In five patients (14%) cervical cord displacement was noted at axial rotation. The foraminal size varied depending on the provocative position, increasing at flexion and decreasing at extension.

CONCLUSION

Kinematic MR imaging in patients with cervical radiculopathy and increasing symptoms at provocative maneuvers provides no additional information for the therapeutic decision-making process.

A new concept for melatonin deficit: on pineal calcification and melatonin excretion

Even though exogenous melatonin has proven to influence sleep and circadian parameters, low endogenous melatonin is not related to sleep disturbances, nor does it predict response to melatonin replacement therapy. In this manuscript, we present a new concept towards a definition of a melatonin deficit. The purpose of the study was to introduce a marker for an intra-individual decrease in melatonin production. Therefore, we developed a method to quantify the degree of pineal calcification (DOC) using cranial computed tomography. Combining pineal DOC with the organs's size, we estimated the uncalcified pineal gland volume. This estimation was positively and significantly associated with 6-sulfatoxymelatonin (aMT6s), collected over 24 hours in urine, in 26 subjects. Data yielded evidence that the decline in aMT6s excretion with age can be sufficiently explained by an increased pineal calcification. These results suggest that DOC might be useful as an indicator of an intra-individual, decreased capability of the pineal gland to produce melatonin. DOC might prove to be a response-marker for melatonin replacement therapy and a vulnerability marker of the circadian timing system.

Hepatomegaly and cholestasis as primary clinical manifestations of an AL-kappa amyloidosis

A 53-year-old man, who presented with weight loss over a period of 10 months, hepatomegaly, markedly raised cholestatic enzymes and Ca 19-9, was initially suspected of suffering from metastatic cholangio-carcinoma. Liver biopsy revealed depositions of AL-amyloid. Further investigations confirmed a generalized amyloidosis. Biopsies taken from the gastric, colonic, and bronchial mucosa all showed depositions of amyloid. A nephrotic syndrome was interpreted as being secondary to the renal involvement. Echocardiography identified changes which were consistent with cardiac involvement. A plasmacytoma or lymphoma was excluded. At the time of diagnosis the patient was in a good physical condition with normal renal function. Within a few weeks the renal function deteriorated and after 2 months the patient developed ascites and became jaundiced. Four months after initial presentation the patient died from cardiac failure.

[Pretarsal platinum-iridium implants for therapy of lagophthalmos in facial paralysis. Preliminary results]

Upper lid closure in facial nerve paresis induced lagophthalmos is often improved by implantation of gold weights. However, the tolerability of gold implants has not always met expectations. We therefore investigated whether results could be improved by implantation of well-tolerated platinum implants.

PATIENTS AND METHODS

Three patients with lagophthalmos received pretarsal platinum-iridium implants in the upper lid. The implants were primary in two patients and secondary in one. In this patient, the previous gold implant had led to marked swelling and redness of the upper lid 6 weeks after surgery. The platinum implants were prefabricated with a radius of 20 mm and weighed between 1.3 and 1.4 g. During implantation, they were individually contoured to fit lidcurvature and attached pretarsally with nonresorbable thread.

RESULTS

Postoperatively, the upper lid of all three patients could be closed completely. The implants healed without irritation. No lid swelling occurred during 2-to 6-month follow-up. Because platinum-iridium alloys have a higher specific gravity (Ptlr 90/10 = 21.65 g/cm3) than gold (18.43 g/cm3), they can attain equal weight at smaller size.

CONCLUSIONS

Our first results show that platinum implants are a feasible alternative to gold implants in treating lagophthalmos due to better biocompatibility and higher specific gravity.

[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.

Extracellular recording in neuronal networks with substrate integrated microelectrode arrays

A photolithographically produced array of 60 substrate-integrated microelectrodes was used for extracellular recording. Neuronal electrical activity was recorded from chicken retinal ganglion cells with or without stimulation by diffuse light. The retina was removed from chicken embryos of embryonic day 14-18. Only cells recorded from day 18 retina would react to photostimulation, increasing their activity when stimulated, corresponding to the developmental time course of photoreceptor differentiation.

A thin film microelectrode array for monitoring extracellular neuronal activity in vitro

A planar array of microelectrodes has been developed for monitoring the electrical activity of neurons in cell culture. The microelectrode array was tested and characterized using impedance measurements and SEM. To verify the spatial sensitivity of the microelectrodes we used a specially developed simulation device.

Formaldehyde, glyoxal, urethane, methyl carbamate, 2,3-butanedione, 2,3-hexanedione, ethyl acrylate, dibromoacetonitrile and 2-hydroxypropionitrile induce chromosome loss in Saccharomyces cerevisiae

Induction of mitotic chromosome loss could be demonstrated for the dialdehyde glyoxal, the diketones 2,3-butanedione and 2,3-hexanedione, ethyl and methyl carbamate, ethyl acrylate, dibromoacetonitrile, 2-hydroxypropionitrile and formaldehyde, but only when they were combined with subacute concentrations of propionitrile, which is a strong inducer of chromosomal malsegregation. The same chemicals did not induce mitotic chromosome loss when applied in pure form. However, glyoxal, ethyl acrylate, dibromoacetonitrile and formaldehyde when applied in pure form also induced mitotic recombination. Respiratory deficiency was induced, in the absence of propionitrile, by these recombinogenic agents and also by 2,3-hexanedione and 2-hydroxypropionitrile which are not recombinogenic.

Absence of macrophage and presence of plasmacellular iron storage in the terminal duodenum of patients with hereditary haemochromatosis

Biopsy specimens of the terminal duodenum obtained from 11 patients with hereditary haemochromatosis were examined by light and electron microscopy. Stainable iron was found in the lamina propria of the terminal duodenum in only 4 patients, all of whom were in an advanced stage of the disease. The iron was localized in the basal parts of the villi, sparing their tips, and between the crypts of Lieberkühn. The iron-storing cells could be identified as plasma cells, in which ferritin and haemosiderin were localized within lysosomes and ferritin molecules scattered in the cell sap. There was no storage of iron in macrophages. These observations demonstrate the impaired iron-storing capacity of macrophages in hereditary haemochromatosis, which may be related to the increased iron absorption in this iron storage disease.

[Alternatives and further development of therapy of acute myeloid leukemia in adults. Update of West German multicenter studies]

The 1982 randomized, multicenter trial on adult-AML in West Germany revealed a superiority of remission duration (p = 0.004) and survival (p = 0.06) for patients receiving monthly myelosuppressive maintenance chemotherapy after TAD9-induction and consolidation as compared to patients without maintenance. In the 1985 pilot study double induction as a new approach followed by consolidation and monthly maintenance in patients up to 60 years of age was found well practicable, with 77% complete remissions and 12% early deaths in 81 patients. In addition preliminary remission duration and survival at 1 1/2 years appear favorable.

Inhibition of lipid peroxidation by superoxide dismutase following regional intestinal ischemia and reperfusion

In a feline model of regional intestinal ischemia, reoxygenation resulted in a rise in the concentration of oxidized glutathione, from 2.3 +/- 0.7 to 4.1 +/- 0.5% of the total glutathione. Also conjugated diene as an indirect measurement for lipid peroxidation increased after reperfusion from 2.5 +/- 0.5 mumol/g to 5.5 +/- 1.2 micrograms mol/g tissue. These results are in line with the hypothesis that ischemia results in an accumulation of hypoxanthine and a conversion of xanthine dehydrogenase into its O2-dependent form. Upon reoxygenation, hypoxanthine can be oxidized giving yield to a burst of O2-. and its interconversion products. These may initiate peroxidative tissue damage. Pretreatment of the cats with superoxide dismutase inhibited the biochemical alterations and protected the tissue from peroxidation damage.

[Acute myeloid leukemia (AML) in adults. Further development of therapy based on clinical phase II and phase III studies]

By a review of relevant clinical studies on adult AML no substantial progress can be seen in the eighties so far. After the development of successful chemotherapy regimens during the seventies, further improvement can only be expected in small steps. Clinical studies, therefore, should concentrate on the analysis of the different components and new elements of treatment in order to utilize and combine them more effectively. For this purpose, a standardization of treatment and, for many aspects, a randomized comparison is inevitable. Thus, the role of monthly maintenance as well as of a special type of immunotherapy could be elucidated for the first time by our multicenter trial.

[Fold formations in the proximal ureter]

Over a period of thirteen years in 28 children (age 4 weeks to 11 years) mucosal membranes of the proximal ureter were diagnosed by intravenous urography. In 61% of all cases the anomalies were demonstrated within the first year of life. Predominantly boys were affected (75%). Most of the associated anomalies (n = 15) were related to the urogenital system (n = 7). The membranes were bilateral in 12 cases and either separate (n = 15) or multiple (n = 25), resulting in a cork-screw-like structure. Minor signs of obstruction of the corresponding renal pelvis were found in 45%, independent of the number of membranes. Urinary tract infection (UTI) occurred in half of all cases. Kidney length was not reduced in any child. The mean serum creatinin (SCR) level was 0.6 +/- 0.4 mg/dl. Surgical correction was never performed. The clinical follow-up investigation (n = 14) after a mean period of 5.1 (1-14) years revealed recurrent UTI in only 2 patients. The mean SCR level remained normal (0.5 +/- 0.3 mg/dl). The tendency of involution of the membranes, supposed by the clinically benign course, is demonstrated to serve as an example. Although a predisposing effect to UTI cannot be excluded, ureteral membranes must be regarded as harmless and transitory anomalies of the growing ureter in childhood which do not require urologic intervention.