Search PubMed⌕ Search

Biomedical subjects

M Hammes

Publications and source records attributed to M Hammes.

12 recordsLinked to original sources
PubMed2004

Hypothalamic activation in trigeminal autonomic cephalgia: functional imaging of an atypical case.

We report headache induced BOLD changes in an atypical case of trigeminal autonomic cephalgia (TAC). A 68-year-old patient was imaged using fMRI during three attacks of a periorbital head-pain with a average duration of 3 min. During the attacks, left sided conjunctival injection, rhinorrhea, lacrimation, facial sweating and hypersalivation were apparent. These attacks were usually partly responsive to oxygen administration but otherwise refractory to any drug. The patient described either attacks with a duration of one minute or less or longer attacks persisting for maximum of 20 min with headaches occurring up to 100 times a day. When considering the symptoms, frequency, duration and therapeutic response of the patient's headache, no clear-cut classification to one of the subtypes of trigeminal autonomic cephalgias (cluster headache, paroxysmal hemicrania, SUNCT) or trigeminal neuralgia was possible. The cerebral activation pattern was similar but not identical to those previously observed in cluster headache and SUNCT with a prominent activation in the hypothalamic grey matter. This case study underlines the conceptual value of the term TAC for the group of headaches focusing around the trigeminal-autonomic reflex. Our results emphasize the importance of the hypothalamus as key region in the pathophysiology of this entity.

Aged↗
PubMed2004

Changes of cerebrovascular response to visual stimulation in migraineurs after repetitive sessions of somatosensory stimulation (acupuncture): a pilot study.

OBJECTIVES: To evaluate the effect of repetitive somatosensory stimulation (acupuncture) on cerebrovascular response in migraineurs by functional transcranial Doppler. METHODS: Changes of cerebral blood flow velocity in the right posterior and left middle cerebral arteries were measured by functional transcranial Doppler during visual stimulation (flickering light over 57 seconds) in 10 migraineurs before and after 10 acupuncture sessions. The same stimulation paradigm was performed in 10 control subjects. Cerebral blood flow velocity data were analyzed with a previously validated technique based on automated stimulus-related averaging. To evaluate the clinical effect of the treatment, a headache diary monitored the frequency and intensity of the migraine attacks. A positive treatment effect was defined as a reduction of at least 50% in the attack frequency or the mean headache intensity (or both). RESULTS: Before treatment, migraineurs showed overshooting cerebral blood flow velocity changes at the beginning and at the end of the stimulation and a delayed decline to baseline compared with control subjects. After treatment, this response pattern was significantly diminished (P</=.05) in those who benefited from treatment (n = 6). Those who did not benefit from treatment (n = 4) showed a significantly (P</=.05) more marked alteration of the cerebral blood flow velocity pattern. CONCLUSIONS: Data indicate that repetitive somatosensory stimulation (acupuncture) might positively influence the abnormal cerebrovascular response in migraineurs. In a subgroup of migraineurs, however, the dysfunction of the cerebrovascular system might deteriorate under the treatment.

Acupuncture Therapy↗
PubMed2003

[Differential and common characteristics of patients with atypical facial pain and craniomandibular dysfunction].

BACKGROUND: Craniomandibular disorders (CMD) and atypical facial pain (AFP) represent a clinical challenge. Whereas CMD patients respond to somatic approaches, somatization should be strictly avoided in AFP. The aim of this study was to establish prognostic criteria to identify an aggravated risk of a chronic course in CMD and AFP. METHOD: A total of 124 consecutive patients with CMD ( n=108) or AFP ( n=16) were examined by two interdisciplinary academic pain centers. Psychometric evaluation was conducted with standardized questionnaires (SCL-90R, STAXI, modified SBAS-IV). All patients were clinically assessed by a maxillofacial surgeon or specialized dentist. RESULTS: The following variables proved to be significant: age (risk for AFP vs CMD increased by 6% p.a.), decreased dysfunction index (13% higher risk for AFP vs CMD), and low scores concerning outwardly directed anger (12% higher risk for AFP vs CMD). There was no correlation between initial pain intensity and somatic parameters of disease as assessed by the standardized clinical examination. Low educational status proved to be the best predictor ( p<0.001) for patients presenting high initial pain with a marked discrepancy between somatic findings and subjective status. CONCLUSIONS: CMD patients differ from AFP patients regarding age, psychosocial isolation, outwardly directed anger, and a decreased dysfunction index. Additionally, initial pain intensity in patients presenting indistinct CMD/AFP can be considered as a valid predictor for a chronic course in pain.

Adolescent↗
PubMed2003

Evanescent-wave trapping and evaporative cooling of an atomic gas at the crossover to two dimensions.

A dense gas of cesium atoms at the crossover to two dimensions is prepared in a highly anisotropic surface trap that is realized with two evanescent light waves. Temperatures as low as 100 nK are reached with 20,000 atoms at a phase-space density close to 0.1. The lowest quantum state in the tightly confined direction is populated by more than 60%. The system provides atoms at a mean distance from the surface as low as 1 microm, and offers intriguing prospects for future experiments on degenerate quantum gases in two dimensions.

Journal Article↗
PubMed2003

Acupuncture Randomized Trials (ART) in patients with migraine or tension-type headache--design and protocols.

BACKGROUND AND OBJECTIVE: We report the design and essentials of the protocols of two Acupuncture Randomized Trials (ART) investigating whether acupuncture is more efficacious than no treatment and minimal acupuncture in the interval treatment of migraine and tension-type headache. DESIGN: Randomized controlled multicenter trials with three treatment arms and a total observation period of 28 weeks. SETTING: 30 practitioners and outpatient units in Germany specialized in acupuncture treatment. PATIENTS: Per study 300 patients with migraine and episodic or chronic tension-type headache, respectively (diagnosis according to the criteria of the International Headache Society). INTERVENTIONS: Patients are randomly assigned to receive either (1) semi-standardized acupuncture (150 patients), (2) standardized minimal acupuncture (75 patients), or (3) no interval treatment for 12 weeks followed by semi-standardized acupuncture (75 patients, waiting list control). Acupuncture treatment consists of 12 sessions per patient over a period of 8 weeks. MAIN OUTCOME MEASURE: Main outcome measure in the migraine trial is the difference between the number of days with headache of moderate or severe intensity during the 4 weeks before randomization and weeks 9 to 12 after randomization. In the study on tension-type headache the main outcome measure is similar to that described above, but for the number of headache days regardless of intensity. OUTLOOK: The results of these two studies (available in 2004) will provide health care providers and policy makers with the information needed to make scientifically sound assessments of acupuncture therapy.

Acupuncture Therapy↗
PubMed2002

[Psychic and somatic findings in jaw or facial pain of unclear origin. Comparison of patients with severe and mild symptoms].

BACKGROUND: Both for medical and dental specialists, patients with facial arthromyalgia (FAM) and acute or chronic atypical facial pain (AFP) often represent a clinical challenge. Only few empirical studies address the possible interaction between facial pain and increased psychosocial stress with a thereby heightened risk for a chronic course of disease. OBJECTIVE: To evaluate whether FAM or AFP - patients initially presenting with high vs. low pain intensity differ in somatic, psychosocial and socioeconomic parameters. METHOD: We chose to study a population with a primary diagnosis of myofascial pain of the jaw muscles or atypical facial pain and excluded patients with disc displacement, acute arthritis and severe arthrosis. Within nine months, 124 consecutive patients with FAM ( n=108) or AFP ( n=16) were referred to the departments of maxillary surgery, dentistry or neurology of two interdisciplinary academic pain centers. Using the patients'ratings on a 100 mm visual analogue scale concerning their pain intensity, the group was divided in a subgroup initially presenting with low (VAS</=5; n=50) and high pain (VAS>5; n=45). Psychometric evaluation was conducted with the SCL-90R (general psychopathology), the State-Trait-Anger-Expression Inventory (STAXI) and a special questionnaire addressing different aspects of chronic pain (modified SBAS-IV). All patients were assessed by a maxillary surgeon/specialized dentist with the help of a detailed, standardized clinical examination (Helkimo-Index). RESULTS: The group of FAM-/AFP - patients according to our inclusion-/exclusion - criteria presenting with a high pain intensity showed more psychosocial withdrawal ( p=0.013), a worse self-rated psychological status ( p=0.033) and a trend towards more somatization ( p=0.093) than patients with lower pain intensity. There was no correlation between initial pain intensity and somatic parameters of disease as assessed by the standardized clinical examination. Low educational status proved to be the best predictor (p<0.001) for belonging to the high (extensive) pain group. CONCLUSIONS: These data suggest that FAM-/ AFP - patients initially presenting with a high pain intensity have an increased risk for psychosocial stress and maladaptive coping behaviour. As both variables are empirically validated risk factors for a chronic course in pain-related disease, these patients should be of special interest for an interdisciplianary therapeutic setting including psychotherapeutic approaches.

Acute Disease↗
PubMed1995

Laparoscopic Swenson pull-through procedure for congenital megacolon.

Constipation that is unresponsive to conventional remedies is the primary symptom of congenital megacolon (ie, Hirschsprung's disease). The cause of congenital megacolon is lack of ganglion cells in the bowel. The laparoscopic Swenson pull-through procedure involves removing the aganglionic segment of the colon, bringing the normally decompressed bowel through the pelvic floor, and anastomosing the bowel to the anorectal verge. Advantages of the laparoscopic approach include shorter lengths of hospital stay and fewer complications resulting from disruption of skin integrity.

Anastomosis, Surgical↗
PubMed1994

Hypocalcemia in end-stage renal disease: a consequence of spontaneous parathyroid gland infarction.

Advances over the last several years have led to a better understanding of the etiology of hyperparathyroidism in renal disease and to more effective means of medical prevention and therapy. Thus, in most dialysis populations, many of the serious complications, such as bone fractures, refractory hypercalcemia, and hyperphosphatemia with vascular and other extraskeletal calcifications, have diminished. Furthermore, more aggressive medical management has decreased the requirement for parathyroidectomy. Unfortunately, not all patients respond to medical management and few still develop refractory hyperparathyroidism with associated morbidity. Of the many complications of refractory hyperparathyroidism in dialysis patients, the development of life-threatening hypocalcemia has not been described. We describe a patient with severe secondary hyperparathyroidism who presented with the acute development of hypocalcemia. To our knowledge, this represents the fourth case, the first reported in a patient with end-stage renal disease, of parathyroid autoinfarction presenting as acute hypocalcemia.

Adult↗
PubMed1994

Effect of polycations on permeability of glomerular epithelial cell monolayers to albumin.

Polycations can interact with the surface negative charges of the glomerular epithelial cells in the kidney and give rise to metabolic alterations. This study examined whether charge neutralization can affect intercellular junctions and increase macromolecular permeability across epithelial monolayers. We examined this question by studying the effect of polycations on the leakage of albumin across monolayers of glomerular epithelial cells. Cells were grown to confluency on filter-lined cups. They were treated apically with cationic bovine gamma globulin or protamine (100 micrograms/ml) for 2 hours at 37 degrees C. After washing the cells, the monolayers were tested for leakage of albumin by the addition of radioactive bovine serum albumin on the apical side and determining the time course of its appearance on the basal side. Polycation treatment caused significant leakage of albumin in the absence of any toxic effect on viability or lactate dehydrogenase release. The leakage was shown to be through the tight junctions of the monolayer. Permeability alterations were compared at 4 degrees C and 37 degrees C to determine whether impairment was due to the membrane ruffling effect of charge neutralization or due to intracellular metabolic changes. Despite equal bindings of polycations at 4 degrees C and 37 degrees C, significant leak occurred only at 37 degrees C, suggesting the role of active processes in the maintenance of permselectivity. This was consistent with the rapid interiorization of the polycation at 37 degrees C after membrane binding. Further substantiation of this point was obtained by studying the protective effect of removing bound polycation with heparin. Removal of polycation after initial binding failed to protect the monolayer from albumin leakage. The conclusion was that neutralization of glomerular epithelial cell surface charges results in subtle impairment of tight junction control of permeability to macromolecules across the monolayer. The impairment was due to active intracellular processes that ensue after polycation binding to cell surface charges and their subsequent internalization.

Animals↗