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Biomedical subjects

J K Krauss

Publications and source records attributed to J K Krauss.

At least 19 recordsLinked to original sources
PubMed2006

Patterns of reoccurrence of segmental dystonia after discontinuation of deep brain stimulation.

The pattern of reoccurrence of symptoms after discontinuation of deep brain stimulation (DBS) has not been systematically studied in dystonia. Eight patients (mean age (SD) 53.8 (14.4) years) with segmental dystonia at a mean follow-up of 11.3 (4.2) months were studied after implantation of bilateral DBS electrodes in the internal globus pallidus using a standard video protocol and clinical rating scales, immediately and at 2 and 4 h after switching off DBS. Dystonic signs returned sequentially, with a rapid worsening of phasic and a slower worsening of tonic dystonic components. In all patients, phasic dystonic features appeared within a few minutes, whereas the tonic elements of dystonia reoccurred with a more variable delay. Differential clinical effects when withdrawing DBS might reflect its influence on different pathophysiological mechanisms in dystonia.

Adult↗
PubMed2006

[Parapharyngeal abscess and osteomyelitic destruction of the odontoid process].

We report the case of a 55 year old man with osteomyelitic destruction of the odontoid process and a parapharyngeal abscess. The patient was admitted with diagnosis of meningitis and degenerative cervical spine disease without compression of spinal cord or nerve roots but progressive impairment of cervical spine mobility. Inflammatory parameters in serum and cerebrospinal fluid were detected and antibiotic therapy was initiated resulting in subjective improvement of symptoms. When impairment of cervical spine motility persisted and gait disturbance developed, a parapharyngeal abscess and an osteomyelitic destruction of the odontoid process caused by infection with staphylococcus aureus was diagnosed. After cleavage of the abscess and four months of antibiotic therapy the gait disturbance disappeared and mild impairment of cervical spine motility persisted.

Anti-Bacterial Agents↗
PubMed2006

Chronic spinal cord stimulation in medically intractable orthostatic tremor.

BACKGROUND: Orthostatic tremor with its sense of unsteadiness when standing may have a devastating effect on affected persons. Currently, there are no other treatment options in those who do not respond or who do not tolerate medical treatment. OBJECTIVES: To report on a pilot study on spinal cord stimulation in medically intractable orthostatic tremor. METHODS: Chronic spinal cord stimulation (SCS) was performed in two patients with medically-intractable orthostatic tremor via quadripolar plate electrodes implanted at the lower thoracic spine. The electrodes were connected to implantable pulse generators. RESULTS: Subjective and objective improvement of unsteadiness was achieved within a frequency range of 50 to 150 Hz, and occurred in the presence of stimulation-induced paraesthesia. With optimized stimulation settings polygraphic electromyelogram (EMG) recordings continued to show the typical 14-16 Hz EMG activity. The beneficial effect of SCS was maintained at long-term follow-up. CONCLUSIONS: The results of this pilot study indicate that SCS may be an option in patients with otherwise intractable orthostatic tremor.

Aged↗
PubMed2006

Oscillatory pallidal local field potential activity correlates with involuntary EMG in dystonia.

The pathophysiology of dystonia is unclear. The authors recorded local field potentials (LFPs) from deep brain stimulation electrodes implanted in the pallidum of 13 dystonic patients. LFP power correlated with the level of dystonic EMG in the sternocleidomastoid, with maximal positive correlations at the lower contacts of pallidal electrodes. The data suggest that the neuronal synchronization indexed by LFP oscillations in the globus pallidus may be mechanistically linked to dystonic EMG activity.

Action Potentials↗
PubMed2006

A systematic review on the diagnosis and treatment of primary (idiopathic) dystonia and dystonia plus syndromes: report of an EFNS/MDS-ES Task Force.

To review the literature on primary dystonia and dystonia plus and to provide evidence-based recommendations. Primary dystonia and dystonia plus are chronic and often disabling conditions with a widespread spectrum mainly in young people. Computerized MEDLINE and EMBASE literature reviews (1966-1967 February 2005) were conducted. The Cochrane Library was searched for relevant citations. Diagnosis and classification of dystonia are highly relevant for providing appropriate management and prognostic information, and genetic counselling. Expert observation is suggested. DYT-1 gene testing in conjunction with genetic counselling is recommended for patients with primary dystonia with onset before age 30 years and in those with an affected relative with early onset. Positive genetic testing for dystonia (e.g. DYT-1) is not sufficient to make diagnosis of dystonia. Individuals with myoclonus should be tested for the epsilon-sarcoglycan gene (DYT-11). A levodopa trial is warranted in every patient with early onset dystonia without an alternative diagnosis. Brain imaging is not routinely required when there is a confident diagnosis of primary dystonia in adult patients, whereas it is necessary in the paediatric population. Botulinum toxin (BoNT) type A (or type B if there is resistance to type A) can be regarded as first line treatment for primary cranial (excluding oromandibular) or cervical dystonia and can be effective in writing dystonia. Actual evidence is lacking on direct comparison of the clinical efficacy and safety of BoNT-A vs. BoNT-B. Pallidal deep brain stimulation (DBS) is considered a good option, particularly for generalized or cervical dystonia, after medication or BoNT have failed to provide adequate improvement. Selective peripheral denervation is a safe procedure that is indicated exclusively in cervical dystonia. Intrathecal baclofen can be indicated in patients where secondary dystonia is combined with spasticity. The absolute and comparative efficacy and tolerability of drugs in dystonia, including anticholinergic and antidopaminergic drugs, is poorly documented and no evidence-based recommendations can be made to guide prescribing.

Botulinum Toxins↗
PubMed2006

Evaluation of surface and volume rendering in 3D-CT of facial fractures.

OBJECTIVES: Three-dimensional computed tomography (3D-CT) of facial fractures has been reported as beneficial using surface (SR) and volume rendering (VR). There are controversial statements concerning the preferable algorithm. The purpose of this study was to evaluate and compare SR and VR for clinical 3D-CT in facial fractures on an experimental basis. METHODS: Multislice CT was obtained in 22 patients with facial fractures using two data acquisition protocols. Five SR and VR post-processing protocols were applied. Five assessors independently evaluated the quality of visualization of the fracture gap and dislocated fragments as well as the overall image quality using a five-point rating scale. The potential benefit of the 3D-images for radiological diagnosis and presentation was evaluated. The influence of the data acquisition protocol was analysed. RESULTS: SR in general achieved better evaluation scores than VR at corresponding thresholds. Variation of evaluation scores for all criteria was found for SR and VR depending on the segmentation threshold. Apart from the overall image quality no significant influence of the data acquisition technique was found for the evaluated criteria. CONCLUSIONS: SR provided sufficient and time efficient means for 3D-visualization of facial fractures in this study. No diagnostic benefit of VR over SR was found.

Adolescent↗
PubMed2005

Laparoscopically assisted peritoneal shunt insertion in hydrocephalus: a prospective controlled study.

BACKGROUND: Shunting of cerebrospinal fluid to the peritoneal cavity is standard therapy for the management of hydrocephalus. Common problems, however, are infection and shunt malfunction, which frequently is related to the peritoneal end of the catheter. Laparoscopic revision of distal shunt malfunction has become popular, but endoscopic techniques for primary placement of the peritoneal catheter are not performed often. This study aimed to compare laparoscopically assisted peritoneal catheter placement with the conventional minilaparotomy technique. METHODS: In the prospective arm of the study, 50 patients underwent laparoscopic distal shunt placement. The findings were compared with those for another group of 50 patients who underwent surgery by the standard transrectal or pararectal approach. Both groups were similar with regard to age, gender, American Society of Anesthesiologists (ASA) scores, indications for surgery, and frequency of previous abdominal operations. RESULTS: No intraoperative complications occurred. The mean time for surgery was 59 min in the laparoscopically assisted treatment group and 49 min in the standard group. During follow-up assessment, 3 instances of distal catheter malfunction or infection (2 malfunctions and 1 infection) occurred in the endoscopic group, and 12 instances (6 malfunctions and 6 infections) occurred in the control group. This difference was statistically significant. CONCLUSIONS: The findings from this prospective controlled study indicate that the risk for long-term complications attributable to distal shunt malfunction is reduced when laparoscopic techniques are used to place the peritoneal end of the shunt catheter.

Adolescent↗
PubMed2004

Normal pressure hydrocephalus: survey on contemporary diagnostic algorithms and therapeutic decision-making in clinical practice.

BACKGROUND: There is no agreement on the best diagnostic criteria for selecting patients with normal pressure hydrocephalus (NPH) for CSF shunting. The primary objective of the present study was to provide a contemporary survey on diagnostic algorithms and therapeutic decision-making in clinical practice. The secondary objective was to estimate the incidence of NPH. METHOD: Standardized questionnaires with sections on the incidence of NPH and the frequency of shunting, evaluation of clinical symptoms, and signs, diagnostic studies, therapeutic decision-making and operative techniques, postoperative outcome and complications, and the profiles of different centers, were sent to 82 neurosurgical centers in Germany known to participate in the care of patients with NPH. FINDINGS: Data were analyzed from 49 of 53 centers which responded to the survey (65%). The estimated annual incidence of NPH was 1.8 cases/100.000 inhabitants. Gait disturbance was defined as the most important sign of NPH (61%). There was a wide variety in the choice of diagnostic tests. Cisternography was performed routinely only in single centers. Diagnostic CSF removal was used with varying frequency by all centers except one, but the amount of CSF removed by lumbar puncture differed markedly between centers. There was poor agreement on criteria for evaluation of continuous intracranial pressure recordings regarding both the amplitude and the relative frequency of B-waves. Both periventricular and deep white matter lesions were present in about 50% of patients being shunted, indicating that vascular comorbidity in NPH patients has gained more acceptance. Programmable shunts were used by more than half of the centers, and newer valve types such as gravitational valves have become more popular. CONCLUSIONS: According to the present survey, new diagnostic and therapeutic concepts on NPH have penetrated daily routine to a certain extent. Wide variability, however, still exists among different neurosurgical centers.

Cerebrospinal Fluid Shunts↗
PubMed2004

Concepts of neurosurgical management of chronic subdural haematoma: historical perspectives.

The history of chronic subdural haematoma (CSH), spanning from its possibly earliest beginnings throughout the centuries until the early 1980s, was investigated within the context of four different epochs. In the 'era of uncertainty', successful trephination, the modem method of choice for the treatment of CSH, was developed by neolithic men. Various historical sources indicate that patients with CSH might have undergone surgery at that time. CSH might have been one of the ailments that had spectacular courses of salvation after trephination. The entity of CSH was first described in the 'era of pioneers' in the seventeenth century by Johann Jacob Wepfer. The misconception of 'pachymeningitis hemorrhagica interna' was introduced by Rudolf Virchow in 1857. By the end of the nineteenth century it became more widely accepted that trauma was a possible cause of CSH. Successful neurosurgical treatment of CSH was first reported by Hulke in 1883. Putnam and Cushing, in 1925, focused on surgery as the treatment of choice for CSH. In the 'era of diagnostic refinement', the introduction of pneumencephalography and angiography allowed the diagnosis of CSH much earlier. Subsequently, the typical signs and symptoms of patients suffering from CSH changed from apathy and coma to headaches and discrete focal neurological symptoms. In the 'era of surgical routine', neurosurgical approaches became smaller and less invasive. Removal of the haematoma was identified as the primary goal of surgery. The use of closed system drainage markedly improved reexpansion of the brain after surgery. Burr hole craniostomy and twist drill craniostomy became the surgical treatment of first choice because of their low morbidity and mortality. There is growing evidence, however, that the neurosurgical learning curve has reached a plateau.

Cerebral Angiography↗
PubMed2003

Risperidone-responsive segmental dystonia and pallidal deep brain stimulation.

A 67-year-old man with risperidone-responsive segmental dystonia underwent bilateral deep brain stimulation (DBS) of the globus pallidus internus. Prospectively, the authors assessed the Burke-Fahn-Marsden Dystonia Rating Scale in medication (M) and stimulation (S) "on"/"off" states. With DBS at 9 months, the score improved by 86% to 8.5 in M-"on"/S-"on" and 12.5 in M-"off"/S-"on." Studies of the effects of DBS and concomitant medication may be warranted in selected patients treated by DBS for dystonia.

Aged↗
PubMed2003

Differential modulation of subcortical target and cortex during deep brain stimulation.

The combination of electrical deep brain stimulation (DBS) with functional imaging offers a unique model for tracing brain circuitry and for testing the modulatory potential of electrical stimulation on a neuronal network in vivo. We therefore applied parametric positron emission tomography (PET) analyses that allow characterization of rCBF responses as linear and nonlinear functions of the experimentally modulated stimulus (variable stimulator setting). In patients with electrodes in the thalamic ventrointermediate nucleus (VIM) for the treatment of essential tremor (ET) here we show that variations in voltage and frequency of thalamic stimulation have differential effects in a thalamo-cortical circuitry. Increasing stimulation amplitude was associated with a linear raise in rCBF at the thalamic stimulation site, but with a nonlinear rCBF response in the primary sensorimotor cortex (M1/S1). The reverse pattern in rCBF changes was observed with increasing stimulation frequency. These results indicate close connectivity between the stimulated nucleus (VIM) and primary sensorimotor cortex. Likewise, stimulation parameter-specific modulation occurs at this simple interface between an electrical and a cerebral system and suggests that the scope of DBS extends beyond an ablation-like on-off effect: DBS could rather allow a gradual tuning of activity within a neuronal circuit.

Aged↗
PubMed2003

Outcome of contemporary surgery for chronic subdural haematoma: evidence based review.

OBJECTIVE: To evaluate the results of surgical treatment options for chronic subdural haematoma in contemporary neurosurgery according to evidence based criteria. METHODS: A review based on a Medline search from 1981 to October 2001 using the phrases "subdural haematoma" and "subdural haematoma AND chronic". Articles selected for evaluation had at least 10 patients and less than 10% of patients were lost to follow up. The articles were classified by three classes of evidence according to criteria of the American Academy of Neurology. Strength of recommendation for different treatment options was derived from the resulting degrees of certainty. RESULTS: 48 publications were reviewed. There was no article that provided class I evidence. Six articles met criteria for class II evidence and the remainder provided class III evidence. Evaluation of the results showed that twist drill and burr hole craniostomy are safer than craniotomy; burr hole craniostomy and craniotomy are the most effective procedures; and burr hole craniostomy has the best cure to complication ratio (type C recommendation). Irrigation lowers the risk of recurrence in twist drill craniostomy and does not increase the risk of infection (type C recommendation). Drainage reduces the risk of recurrence in burr hole craniostomy, and a frontal position of the drain reduces the risk of recurrence (type B recommendation). Drainage reduces the risk of recurrence in twist drill craniostomy, and the use of a drain does not increase the risk of infection (type C recommendation). Burr hole craniostomy appears to be more effective in treating recurrent haematomas than twist drill craniostomy, and craniotomy should be considered the treatment of last choice for recurrences (type C recommendation). CONCLUSIONS: The three principal techniques-twist drill craniostomy, burr hole craniostomy, and craniotomy-used in contemporary neurosurgery for chronic subdural haematoma have different profiles for morbidity, mortality, recurrence rate, and cure rate. Twist drill and burr hole craniostomy can be considered first tier treatment, while craniotomy may be used as second tier treatment. A cumulative summary of data shows that, overall, the postoperative outcome of chronic subdural haematoma has not improved substantially over the past 20 years.

Chronic Disease↗
PubMed2002

Polyethylene sheath device to reduce tumor cell seeding along the needle tract in percutaneous biopsy.

BACKGROUND: Minimally invasive techniques such as percutaneous biopsy of suspected malignancies are used widely. Besides bleeding, tumor cell seeding along the needle or instrument tract is of concern. METHODS: We have developed a polyethylene-sheath device (PSD) to reduce the risk of cell spread when withdrawing a biopsy instrument. The mechanism was tested for its feasibility with a model taking biopsies from lamb liver presoaked with fluorescein dye underneath a specimen of lamb muscle. RESULTS: Fluorescence microscopic examination did not demonstrate fluorescent dye along the needle tract when the PSD was used, whereas there was marked staining in controls. The PSD was intact after having been used to perform the biopsies. CONCLUSIONS: The PSD reduces the risk of cell spread along instrument tracts.

Animals↗
PubMed2002

Pallidal deep brain stimulation in patients with cervical dystonia and severe cervical dyskinesias with cervical myelopathy.

OBJECTIVES: Surgical treatment of complex cervical dystonia and of cervical dyskinesias associated with cervical myelopathy is challenging. In this prospective study, the long term effect of chronic pallidal stimulation in cervical dystonia and on combining the technique with spinal surgery in patients with severe cervical dyskinesias and secondary cervical myelopathy is described. METHODS: Eight patients with a history of chronic dystonia who did not achieve adequate benefit from medical treatment or botulinum toxin injection participated in the study. Five patients had complex cervical dystonia with tonic postures and phasic movements. Three patients had rapidly progressive cervical myelopathy secondary to severe cervical dyskinesias and dystonia in the context of a generalised movement disorder. Quadripolar electrodes were implanted in the posteroventral lateral globus pallidus internus with stereotactic CT and microelectrode guidance. In the three patients with secondary cervical myelopathy, spinal surgery was performed within a few weeks and included multilevel laminectomies and a four level cervical corporectomy with spinal stabilisation. RESULTS: Improvement of the movement disorder was noted early after pallidal surgery, but the full benefit could be appreciated only with a delay of several months during chronic stimulation. Three months after surgery, patients with cervical dystonia had improved by 38% in the severity score, by 54% in the disability score, and by 38% in the pain score of a modified version of the Toronto western spasmodic torticollis rating scale. At a mean follow up of 20 months, the severity score had improved by 63%, the disability score by 69%, and the pain score by 50% compared with preoperatively. There was also sustained amelioration of cervical dyskinesias in the three patients who underwent spinal surgery. Lead fractures occurred in two patients. The mean amplitude needed for chronic deep brain stimulation was 3.8 V at a mean pulse width of 210 micros, which is higher than that used for pallidal stimulation in Parkinson's disease. CONCLUSIONS: Chronic pallidal stimulation is effective for complex cervical dystonia and it is a useful adjunct in patients with cervical dyskinesias and secondary cervical myelopathy who undergo spinal surgery.

Adult↗
PubMed2002

Deep brain stimulation of the centre median-parafascicular complex in patients with movement disorders.

The centre median-parafascicular (CM-Pf) complex of the thalamus is considered to be a possible target for deep brain stimulation (DBS) in patients with movement disorders. In a prospective study on the effect of CM-Pf DBS versus somatosensory thalamic DBS on chronic neuropathic pain, three of 12 patients had additional movement disorders. Bifocal quadripolar electrodes were implanted by computed tomography guided stereotactic surgery under local anaesthesia contralaterally to the side of the pain for test stimulation. Two of the three patients with movement disorders had permanent implantation of CM-Pf electrodes. During test stimulation of the left CM-Pf complex for several days, a 67 year old woman received no benefit with respect to the neuropathic pain, but the choreoathetotic movements of her right foot ceased. As the pain syndrome was not improved, she decided not to have permanent implantation. A 74 year old man with postzoster neuralgia and allodynia enjoyed excellent relief from his pain with chronic CM-Pf DBS. In addition, improvement in the tremor at rest was noted. A 72 year old man had sustained reduction in his stump dyskinesias. Further evaluation of the possible role of the "forgotten" central and medial thalamic nuclei in the treatment of movement disorders may be warranted.

Aged↗
PubMed2002

Effect of chronic pallidal deep brain stimulation on off period dystonia and sensory symptoms in advanced Parkinson's disease.

OBJECTIVE: To investigate the efficacy of chronic pallidal deep brain stimulation (DBS) on off period dystonia, cramps, and sensory symptoms in advanced Parkinson's disease (PD). METHODS: 16 patients (6 women, 10 men; mean age at surgery 65 years) suffering from advanced PD were followed up prospectively for one year after implantation of a monopolar electrode in the posteroventral lateral globus pallidus internus. Unilateral DBS was performed in 9 patients. 10 patients had bilateral procedures (contemporaneous bilateral surgery in 7 and staged bilateral surgery in 3 instances). The decision whether to perform unilateral or bilateral surgery depended on the clinical presentation of the patient. Patients were formally assessed preoperatively, at 3-5 days, 3 months, and 12 months after surgery. RESULTS: In patients who underwent unilateral surgery, pain was present in 7 (78%), off dystonia in 5 (56%), cramps in 6 (67%), and dysaesthesia in 4 (44%). In patients who underwent bilateral surgery, pain was present in 7 (70%), off dystonia in 6 (60%), cramps in 7 (70%), and dysaesthesia in 4 (40%). With unilateral DBS, contralateral off period dystonia was improved by 100% at 1 year postoperatively, pain by 74%, cramps by 88%, and dysaesthesia by 100%. There was less pronounced amelioration of ipsilateral off period dystonia and sensory symptoms. With bilateral DBS, total scores for dystonia were improved by 86%, for pain by 90%, for cramps by 90%, and for dysaesthesia by 88%. The benefit appeared early at the first evaluation 3-5 days after surgery and was stable throughout the follow up period. CONCLUSIONS: Pallidal DBS yields major improvement of off period dystonia, cramps, and sensory symptoms in patients with advanced PD.

Adult↗