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H Arnold

Publications and source records attributed to H Arnold.

At least 19 recordsLinked to original sources
PubMed2006

Prospective studies in patients with intraventricular haemorrhage without the capacity to give consent in Germany--a legal dilemma.

OBJECTIVE: The prognosis of intracranial haemorrhage with ventricular participation is poor. The acute onset of hydrocephalus has to be treated with an external ventricular drainage. However, intraventricular blood clots often obstruct the drainage catheter; the reinsertion is usually associated with an increased risk of complications. Therefore, intraventricular thrombolysis using recombinant tissue plasminogen activator (rt-PA), urokinase or streptokinase has been performed in several cases. In Germany, rt-PA does not have approval for intraventricular applications, and the risks and benefits of this treatment are as yet unclear. Several authors recommend its use only in the frame of prospective studies, meaning that intraventricular administration of thrombolytic agents within an individual therapy trial could be viewed as medical malpractice. METHODS: We designed a national prospective randomised and controlled study in patients with intraventricular haemorrhage to investigate the risks and effects of intraventricular rt-PA treatment. The local ethics committee and lawyers did not accept the study protocol due to a non-acceptable risk of complications. In two further conferences, the risk of undertreatment in the control group was a major reason not to accept the protocol. We discuss the conflicts of law in related studies. CONCLUSIONS: There is a need for a solution to the legal conflicts of medical malpractice, unclear risk-benefit ratio and unfeasibility due to risk of complications or undertreatment in studies with patients without the capacity to give informed consent.

Antifibrinolytic Agents↗
PubMed2006

[Specific strength measurement of musculus abductor pollicis brevis in order to objectively evaluate muscle regeneration after carpal tunnel release surgery].

47 patients with a carpal tunnel syndrome were preoperatively examined not only by electrophysical studies (nerve velocity and distal motoric latency) and clinical tests (Phalen's sign, Tinel's sign) but also by measuring the strength of the M. abductor pollicis brevis with a specifically designed strength-testing unit. 30 patients agreed to participate in a voluntary postoperative examination. In the 45 degrees -measurement there was a relative strength loss of the injured hand's thumb of about 25 % in comparison with the healthy hand preoperatively. The postoperative strength disadvantage amounted to only 10 %. Measurement of the strength in the neutral zero method showed a relative strength loss of the injured hand's thumb of 8 % while postoperatively there was even a strength advantage of 9 % in comparison with the thumb of the healthy hand. Both methods showed a relevant and significant postoperative strength increase of the injured hand's thumb. We could prove a significant correlation (p = 0.03) of the neutral zero strength measurement and the distal motoric latency of the median nerve. Furthermore, we could show a trend for a correlation between the neutral zero strength measurement and the median motoric velocity. In conclusion, it can be said that the special strength measurement of the M. abductor pollicis brevis is an important parameter to objectively evaluate the motoric symptomatology in carpal tunnel syndrome patients.

Adult↗
PubMed2006

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Journal Article↗
PubMed2005

Infarction of the right hemisphere in a patient with antiphospholipid antibody syndrome.

Hemicraniectomy as a surgical treatment for intracranial pressure following large ischemic lesions is widely practiced in selected patients. The antiphospholipid antibody syndrome (APS), a disorder characterized by recurrent arterial and venous thrombosis, is a very rare cause of space occupying ischemic lesions. We present a case of a 35 year old female diagnosed with APS who initially presented with small ischemic lesions and within days developed a massive near-total infarction of the right hemisphere. Because of central nervous system, skin and systemic manifestations Sneddon's syndrome and catastrophic antiphospholipid antibody syndrome (CAPS) remained a possible diagnoses. Sneddon's syndrome is a non-inflammatory occlusive arteriopathy of small and medium size arteries predominantly of the skin and brain, whereas the catastrophic antiphospholipid antibody syndrome is characterized by acute multi-organ system thrombosis of small and large vessels. In addition to the diagnostic criteria for APS a heterozygous factor V Leiden mutation was found in this patient, which may be a contributing risk factor for cerebral ischemia. When considering invasive decompressive procedures the neurosurgeon has to be aware of the poor prognosis of some forms of APS with systemic manifestations.

Adult↗
PubMed2005

[Lesser toe deformities. Definition, pathogenesis, and options for surgical correction].

Whereas in the past resection arthroplasty was - in analogy to hallux valgus surgery - the preferred therapy to correct lesser toe deformities, the point of view has undergone a change. Much interest is directed toward functional aspects that require reconstructive management. Whenever possible the integrity of joint play should be saved. Above all the metatarsophalangeal joint of the lesser toes is worth being preserved to prevent a severe disturbance of the biomechanics of the foot. Tendon transfers and subtle corrective osteotomies such as the Weil procedure allow restricting resection procedures to contraction deformities.

Arthroplasty↗
PubMed2005

Cerebellar haemorrhage and tension pneumocephalus after resection of a Pancoast tumour.

We present an unusual case of cerebellar haemorrhage followed by tension pneumocephalus several days after thoracotomy for resection of a Pancoast tumour. The postoperative course of the 32-year-old patient was complicated by a cerebellar haemorrhage and hydrocephalus caused by compression of the fourth ventricle. Immediate surgical evacuation of the haemorrhage and placement of an external ventricular drain was performed. Respirator ventilation maintaining a continuous positive airway pressure was required. Following weaning and extubation the patient rapidly deteriorated and became comatose. A cranial CT scan revealed a dilated ventricular system filled with air, and air in the subarachnoid space. Recovery of consciousness was observed after aspiration of intracranial air through the ventricular drainage. Recurrent deterioration of consciousness after repeated air aspiration indicated rapid refilling of the ventricles with air. The patient underwent emergency surgical re-exploration of the thoracic resection cavity: dural lacerations of the cervico-thoracic nerve roots C8 and Th1 were identified. Subarachnoid-pleural fistula, cerebellar haemorrhage and tension pneumocephalus after discontinuation of continuous positive airway pressure respiration are unusual complications of thoracic surgery. We discuss the putative pathomechanisms and present a brief review of the literature.

Adult↗
PubMed2005

Rapid manifestation of cervical vertebral osteomyelitis.

Within 10 days after cystoscopy causing urosepsis this patient developed persistant neckpain as initial symptom of vertebral osteomyelitis. E. coli was isolated from urine, blood cultures and later from bone biopsy. Antibiotic treatment did not stop the progress of the disease. A transverse spinal cord syndrome occurred due to a pathological fracture of C5 and C6 and operative decompression was necessary. The rapid onset of osteomyelitis was impressive. For effective treatment of bacterial osteomyelitis a bone biopsy is sometimes unavoidable and indicated.

Anti-Bacterial Agents↗
PubMed2005

Survey of clinical allergy services provided by clinical immunologists in the UK.

BACKGROUND: The UK National Health Service is failing to meet the need for diagnosis and treatment of allergic disorders, which are common and increasing in prevalence. The House of Commons select committee report on allergy services highlighted the inequalities and urgent need for investment. AIM: To survey the allergy workload provided by clinical immunologists to inform service planning and resource allocation. METHODS: The allergy services performed by clinical immunologists during a 12 month period from 1 April 2003 to 31 March 2004 were surveyed by means of a questionnaire via supra-regional audit groups. RESULTS: The immunology centres surveyed serve 32 million people and offer almost the complete repertoire of a specialised allergy service. There were large variations in clinic capacity, new referrals, appointment duration, and service configuration. Services were largely consultant delivered, but availability of joint clinics with paediatricians and anaesthetists was locally variable. Novel service delivery models utilising nurses and clinical assistants have been developed and merit further investigation. CONCLUSION: Consultant immunologists and trainees currently make a major contribution to the development and provision of specialised allergy services. Consultant immunologists will probably remain key providers of tertiary level allergy care in the UK in the long term (in line with other countries) and will be pivotal in supporting and developing the provision of equitable national access to specialist allergy services in a timely manner. Rapid progress in developing the new specialty of allergy and securing better access to services for patients in the short term will be best served by strengthening the collaborative relationship between allergists and clinical immunologists.

Adult↗
PubMed2004

Depletion of MAP2 expression and laminar cytoarchitectonic changes in dorsolateral prefrontal cortex in adult autistic individuals.

The neuropathological substrates underlying the characteristic clinical phenotype of autism are unknown. Neuroimaging studies have identified a decrease in task-related activation in the dorsolateral prefrontal cortex in autism. In the current study, we have analysed the dorsolateral prefrontal cortex in two adult individuals with a clinical diagnosis of autism, using Nissl staining and MAP2 immunohistochemistry. There was unchanged density of both neuronal and glial cell pools, although the autistic individuals had ill-defined neocortical cellular layers, substantially depleted MAP2 neuronal expression, and reduced dendrite numbers. Further studies on a larger number of individuals with autism are needed to establish the clinical relevance of the described changes, especially to determine whether the loss of dendritic markers is age associated or disease specific.

Adult↗
PubMed2003

Molecular approaches to brain tumour invasion.

In glioma cells, the stimulatory input of extracellular matrix components and an increased sensitivity to growth factors result in a high proliferative and migratory behaviour. Cell surface receptor interactions play pivotal roles in converging information about conditions in the environment immediately outside the cell. The transduced signal, in turn induces a response within the cell that provokes a specific behaviour. Cellular migration and cell proliferation are interwoven processes that share several common intracellular pathways. The major cross-links are the phosphoinositol phosphate regulating enzymes, PI-3 kinase and PTEN, the focal adhesion kinase (FAK) and the tumour suppressor p53. An understanding of the interaction between the molecular participants involved in migration and proliferation will promote the design of new treatments. A full understanding of the basis of the invasiveness of tumour cells remains elusive. Gene and protein expression are being studied, using modern techniques such as microarray analysis, SAGE and 2-D protein gels. Transient and permanent protein-protein interactions and recruitment of proteins to specialised cellular domains are equally important in regulating cellular invasion and presumably will attract more attention in future.

Animals↗
PubMed2003

Temozolomide induces apoptosis and senescence in glioma cells cultured as multicellular spheroids.

Temozolomide is an alkylating cytostatic drug that finds increasing application in the treatment of melanoma, anaplastic astrocytoma and glioblastoma multiforme. The compound is a prodrug that decomposes spontaneously, independent of an enzymatic activation step. DNA methylation induces futile mismatch repair cycles and depletion of the DNA repair enzyme O(6)-methylguanine-DNA methyltransferase should then initiate programmed cell death. We show drug-dependent inhibition of tumour growth in a three-dimensional cell culture model of the glioma cell lines U87MG and GaMG. Migrational behaviour of the glioblastoma cells remained unaltered. However, coincubation of tumour spheroids with primary brain aggregates showed reduced tumour cell invasion into brain tissue in the presence of temozolomide. This was not achieved by slowing cellular migration, as temozolomide-treated cells displayed no reduced motility. By transferase-mediated dUTP nick-end labelling (TUNEL) of apoptotic nuclei, we found that the drug was able to induce apoptosis throughout the tumour cell spheroids. Apoptosis was highest in the core region of the spheroids. Repetitive application of sublethal doses of temozolomide to multicellular spheroids resulted in the development of drug resistance in GaMG cells. We suggest that temozolomide is a strong initiator of apoptosis in glioblastoma tumour cells in a spheroid cell culture system, when cells are already in a stressful environment.

Antineoplastic Agents, Alkylating↗
PubMed2003

Cerebral haemodynamic pathologies in HELLP syndrome.

The syndrome of haemolysis, elevated liver enzymes and low platelets (HELLP syndrome) is understood as a unique variant of severe preeclampsia. This disorder complicates between 2 and 7% of gestations and is associated with a high perinatal morbidity and a maternal morbidity ranging between 1 and 4%. Intracerebral complications only rarely occur, especially intracerebral haemorrhage was described only in single cases, often correlated with fatal maternal outcome. The analysis of patients with HELLP syndrome treated at our hospital revealed three cases with severe neurological deterioration. Possible pathogenetic factors are discussed.

Adult↗
PubMed2002

An in vitro study to evaluate the accuracy of stereotactic localization using magnetic resonance imaging by means of the Leksell stereotactic system.

The advantages of using magnetic resonance imaging (MRI) as opposed to computed tomographic (CT) scans or ventriculography in stereotactic surgery include the increased tissue contrast of the lesion or target, direct non-reformatted multiplanar imaging and target coordinate determination as well as reduced imaging artefacts produced by the stereotactic frame. One disadvantage of MR stereotaxis, however, is the potential for anatomic inaccuracy due to equipment-induced inhomogeneities of the magnetic field. The authors present an experimental study on an in vitro model to examine the accuracy of target localization using the Leksell stereotactic frame and MR imaging. Ten formalin-fixed brains taken from patients who had died of non-neurological diseases were sealed in a properly modelled plaster-cast shell simulating the skull bone. These models were fixed in the Leksell stereotactic frame and high-field MR images were performed (Siemens Magnetom SP 1.5 Tesla, T1-weighted spin echo sequences, TR/TE 600/15 ms, slice thickness 2 mm, FOV 300 mm). Following electrocoagulation of different targets on both lentiforme nuclei, the localization and extension of the lesions were controlled by MRI. A gross-/histopathological verification was performed. This model allows a good representation of the anatomic structures without any artefacts. The postoperative MRI control and the pathological examination of the lesions matched well with the preoperatively defined targets. The correlation of coordinates and measurements obtained with the pathological studies were within a +/- 2 mm range in all cases.

Brain↗
PubMed2002

A prospective study of vaginal pH as a predictor of preterm delivery.

OBJECTIVE: To test the usefulness of vaginal pH determinations in the prediction of the risk of preterm delivery at or before 36 weeks of gestation. METHODS: This was a prospective study of asymptomatic pregnant women. Vaginal pH was determined using pH paper in a sterile speculum examination during prenatal visits. Patients were followed to delivery and hospital records were reviewed to extract obstetric information. A total of 308 women agreed to participate and met the criteria for enrolment. Preterm delivery was defined as delivery at or prior to 36 weeks of gestation. Abnormal pH was defined as a pH of > 5.0. RESULTS: Abnormal vaginal pH was associated with increased risk of preterm delivery, (OR 3.3, 95% CI 1.15, 9.2; p = 0.02). In the first trimester, an abnormal vaginal pH was not associated with preterm delivery (p = 0.3). After the first trimester, a vaginal pH of 5.0 or greater was associated with increased risk of preterm delivery (OR 9.6, 95% CI 2.0, 45.5; p = 0.001) as well as delivering an infant of less than 2500 g (OR 3.1, 95% CI 1.2, 7.8; p = 0.015). History of a previous preterm delivery was associated with increased risk of preterm delivery (OR 6.2, 95% CI 1.6, 23.7; p = 0.02). A logistic regression model used to control for a history of preterm delivery and race showed abnormal vaginal pH to remain as an independent predictor of preterm delivery (p = 0.01). CONCLUSIONS: High vaginal pH (> or = 5.0) identified women at risk for preterm delivery.

Adult↗
PubMed2001

Twenty colloid cysts--comparison of endoscopic and microsurgical management.

The management of colloid cyst remains controversial, evaluation of the competing methods seems to be necessary. We report on our experience with colloid cysts in the last decade: ten were managed solely endoscopically, 10 were resected microsurgically (9 via a transcortical/transventricular, 1 via a transcallosal approach). The outcome in the endoscopic group was excellent in 9 cases and unsatisfying in 1 case (recurrence). In the microsurgical group we achieved a good outcome in 5 of 10 cases, a fair outcome in 4 cases and 1 lethal outcome (caused by pulmonary embolism). Complications in the endoscopic group: one intraoperative bleeding, 1 stitch granuloma, 1 mispuncture of the ventricle, and 1 meningitis. Complications in the microsurgical group: 1 subdural effusion, 1 flap infection, 1 mild hemiparesis, 1 transient impairment of consciousness and 1 pulmonary embolism. Mean operative time and length of hospitalization of the endoscopic group were clearly shorter than in the microsurgical group: 91 min versus 267 min time of surgery, 5.1 days versus 18.9 days of hospitalization. Complete resection was achieved in 8 of 10 cases of microsurgery, and in 3 of 10 cases in endoscopy. Endoscopic management results in lower costs and superior patients' comfort. The reduced number of total resections in the endoscopic group may lead to a higher recurrence rate in long-term follow-up, which might be a serious disadvantage of endoscopy. However, more experience in the endoscopic techniques may result in a higher rate of total resection of colloid cysts.

Adult↗