Czech Registry of Monoclonal Gammopathies - Technical Solution, Data Collection and Visualisation.

BACKGROUND: The Registry of Monoclonal Gammopathies (RMG) was established by the Czech Myeloma Group in 2007. RMG is a registry designed for the collection of clinical data concerning diagnosis, treatment, treatment results and survival of patients with monoclonal gammopathies. Data on patients with monoclonal gammopathy of undetermined significance (MGUS), Waldenström macroglobulinaemia (WM), multiple myeloma (MM) or primary AL ("amyloid light-chain") amyloidosis are collected in the registry. DATA: Nineteen Czech centres and four Slovak centres currently contribute to the registry. The registry currently contains records on more than 5,000 patients with MM, almost 3,000 patients with MGUS, 170 patients with WM and 26 patients with primary AL amyloidosis, i.e. more than 8,000 records on patients with monoclonal gammopathies altogether. RESULTS: This paper describes technology employed for the collection, storage and subsequent online visualisation of data. The CLADE-IS platform is introduced as a new system for the collection and storage of data from the registry. The form structure and functions of the new system are described for all diagnoses in general; these functions facilitate data entry to the registry and minimise the error rate in data. Publicly available online visualisations of data on patients with MGUS, WM, MM or primary AL amyloidosis from all Czech or Slovak centres are introduced, together with authenticated visualisations of data on patients with MM from selected centres. CONCLUSION: The RMG represents a data basis that makes it possible to monitor the disease course in patients with monoclonal gammopathies on the population level.Key words: Registry of Monoclonal Gammopathies - RMG - registries - monoclonal gammopathies - CLADE-IS - data visualisation - database.

Computer-aided diagnosis improves detection of small intracranial aneurysms on MRA in a clinical setting.

BACKGROUND AND PURPOSE: MRA is widely accepted as a noninvasive diagnostic tool for the detection of intracranial aneurysms, but detection is still a challenging task with rather low detection rates. Our aim was to examine the performance of a computer-aided diagnosis algorithm for detecting intracranial aneurysms on MRA in a clinical setting. MATERIALS AND METHODS: Aneurysm detectability was evaluated retrospectively in 48 subjects with and without computer-aided diagnosis by 6 readers using a clinical 3D viewing system. Aneurysms ranged from 1.1 to 6.0 mm (mean = 3.12 mm, median = 2.50 mm). We conducted a multireader, multicase, double-crossover design, free-response, observer-performance study on sets of images from different MRA scanners by using DSA as the reference standard. Jackknife alternative free-response operating characteristic curve analysis with the figure of merit was used. RESULTS: For all readers combined, the mean figure of merit improved from 0.655 to 0.759, indicating a change in the figure of merit attributable to computer-aided diagnosis of 0.10 (95% CI, 0.03-0.18), which was statistically significant (F(1,47) = 7.00, P = .011). Five of the 6 radiologists had improved performance with computer-aided diagnosis, primarily due to increased sensitivity. CONCLUSIONS: In conditions similar to clinical practice, using computer-aided diagnosis significantly improved radiologists' detection of intracranial DSA-confirmed aneurysms of ≤6 mm.

The MRI volumetry of the posterior fossa and its substructures in trigeminal neuralgia: a validated study.

PURPOSE: Our aim was to determine whether the anatomical configuration of the posterior fossa and its substructures might represent a predisposition factor for the occurrence of clinical neurovascular conflict in trigeminal neuralgia (TN). METHODS: We used MRI volumetry in 18 patients with TN and 15 controls. The volume of the pontomesencephalic cistern, Meckel's cave and the trigeminal nerve on the clinical and non-affected sides was compared. The reliability has been assessed in all measurements. RESULTS: The posterior fossa volume was not different in the clinical and control groups; there was no difference between the affected and non-affected sides when measuring the pontomesencephalic cistern and Meckel's cave volume either. The volume of the clinically affected trigeminal nerve was significantly reduced, but with a higher error of measurement. CONCLUSIONS: We did not find any association between the clinical neurovascular conflict (NVC) and the size of the posterior fossa and its substructures. MRI volumetry may show the atrophy of the affected trigeminal nerve in clinical NVC.

Ion specific correlations in bulk and at biointerfaces.

Ion specific effects are ubiquitous in any complex colloidal or biological fluid in bulk or at interfaces. The molecular origins of these 'Hofmeister effects' are not well understood and their theoretical description poses a formidable challenge to the modeling and simulation community. On the basis of the combination of atomistically resolved molecular dynamics (MD) computer simulations and statistical mechanics approaches, we present a few selected examples of specific electrolyte effects in bulk, at simple neutral and charged interfaces, and on a short α-helical peptide. The structural complexity in these strongly Coulomb-correlated systems is highlighted and analyzed in the light of available experimental data. While in general the comparison of MD simulations to experiments often lacks quantitative agreement, mostly because molecular force fields and coarse-graining procedures remain to be optimized, the consensus as regards trends provides important insights into microscopic hydration and binding mechanisms.

Two cases of improvement of smooth pursuit eye movements after selective posterior rhizotomy.

OBJECTIVE: Selective posterior rhizotomy (SPR) represents a standard neurosurgical approach in the treatment of spasticity in children with cerebral palsy (CP). Beside the reduction of spasticity in lower limbs, SPR may have suprasegmental effects, considerably above the surgery site. In this communication, we report on the improvement of smooth pursuit eye movements (SPEM) in two children after SPR. MATERIAL AND METHODS: Four children with CP underwent SPR. Eye movements were registered by infrared video-oculography before and after the surgery. RESULTS: The analysis of SPEM showed the improvement of the correlation coefficient of the eye response to the stimulus after SPR in two subjects. Improvement of SPEM performance was largely due to suppression of spontaneous fixation nystagmus. CONCLUSION: SPR may lead to the improvement of SPEM in children with CP. The influence of SPEM improvement on quality of life in a group of severely disabled nonambulant children with CP remains to be assessed.

Lumbar pressure and transcranial Doppler sonography in children with scaphocephaly.

The primary aim of this study was to assess whether there exists a relationship between lumbar cerebrospinal fluid (CSF) pressure and intracranial blood flow velocities as measured by transcranial Doppler sonography (TCD) in children with scaphocephaly. Another aim was to compare pre- and postoperative TCD. Using a transducer, lumbar CSF pressure (LP) was assessed in 21 children with scaphocephaly. TCD was performed, and the pulsatility index (PI) and the resistance index (RI) were obtained before and after cranioplasty. In 17 children LP was higher than the reference values. No significant differences were found in PI and RI indices before and after cranioplasty. LP values were significantly higher in children older than 6 months. There was no association between LP and PI and RI indices. In children with scaphocephaly a higher LP can be expected with age. Moreover, TCD is not a reliable tool in predicting abnormal LP values.

Co-ion and ion competition effects: ion distributions close to a hydrophobic solid surface in mixed electrolyte solutions.

We consider within a modified Poisson-Boltzmann theory an electrolyte, with different mixtures of NaCl and NaI, near uncharged and charged solid hydrophobic surfaces. The parametrized potentials of mean force acting on Na+, Cl-, and I- near an uncharged self-assembled monolayer were deduced from molecular simulations with polarizable force fields. We study what happens when the surface presents negative charges. At moderately charged surfaces, we observe strong co-ion adsorption and clear specific ion effects at biological concentrations. At high surface charge densities, the co-ions are pushed away from the interface. We predict that Cl- ions can also be excluded from the surface by increasing the concentration of NaI. This ion competition effect (I- versus Cl-) may be relevant for ion-specific partitioning in multiphase systems where polarizable ions accumulate in phases with large surface areas.

Peptide adsorption on a hydrophobic surface results from an interplay of solvation, surface, and intrapeptide forces.

The hydrophobic effect, i.e., the poor solvation of nonpolar parts of molecules, plays a key role in protein folding and more generally for molecular self-assembly and aggregation in aqueous media. The perturbation of the water structure accounts for many aspects of protein hydrophobicity. However, to what extent the dispersion interaction between molecular entities themselves contributes has remained unclear. This is so because in peptide folding interactions and structural changes occur on all length scales and make disentangling various contributions impossible. We address this issue both experimentally and theoretically by looking at the force necessary to peel a mildly hydrophobic single peptide molecule from a flat hydrophobic diamond surface in the presence of water. This setup avoids problems caused by bubble adsorption, cavitation, and slow equilibration that complicate the much-studied geometry with two macroscopic surfaces. Using atomic-force spectroscopy, we determine the mean desorption force of a single spider-silk peptide chain as F = 58 +/- 8 pN, which corresponds to a desorption free energy of approximately 5 k(B)T per amino acid. Our all-atomistic molecular dynamics simulation including explicit water correspondingly yields the desorption force F = 54 +/- 15 pN. This observation demonstrates that standard nonpolarizable force fields used in classical simulations are capable of resolving the fine details of the hydrophobic attraction of peptides. The analysis of the involved energetics shows that water-structure effects and dispersive interactions give contributions of comparable magnitude that largely cancel out. It follows that the correct modeling of peptide hydrophobicity must take the intimate coupling of solvation and dispersive effects into account.

Specific ion adsorption and surface forces in colloid science.

Mean-field theories that include nonelectrostatic interactions acting on ions near interfaces have been found to accommodate many experimentally observed ion specific effects. However, it is clear that this approach does not fully account for the liquid molecular structure and hydration effects. This is now improved by using parametrized ionic potentials deduced from recent nonprimitive model molecular dynamics (MD) simulations in a generalized Poisson-Boltzmann equation. We investigate how ion distributions and double layer forces depend on the choice of background salt. There is a strong ion specific double layer force set up due to unequal ion specific short-range potentials acting between ions and surfaces.

Amygdalar volume and psychiatric symptoms in Alzheimer's disease: an MRI analysis.

OBJECTIVES: We measured the volumes of the amygdala to test the hypothesis that the reduction of amygdalar volume may be associated with psychiatric symptoms in Alzheimer's disease. MATERIALS AND METHODS: Twenty-seven patients underwent neuropsychological investigation including the assessment of general clinical severity by the Mini-Mental State Examination (MMSE) and Neuropsychiatric Inventory (NPI). All patients underwent magnetic resonance imaging (MRI) of the head, from which the volumes of the amygdalae were measured. The obtained values were compared with those of controls (n = 15). RESULTS: Patients with Alzheimer's dementia showed significant reduction in MRI volumetric measurements compared with controls. We found a significant correlation of MMSE score and absolute amygdala volume (r = 0.62, P < 0.01). Neither the absolute nor relative volume of the amygdala showed any correlation with NPI scores. CONCLUSIONS: The atrophy of the amygdala does not have a direct association with the existence of neuropsychiatric symptoms. MRI volumetry of the amygdala may be relevant as a marker of dementia severity in Alzheimer's disease.

[Suprasegmental effects of selective posterior rhizotomy]. / Suprasegmentální úcinky selektivní zadní rizotomie.

The occurrence of spasticity is most commonly attributed to the lack of presynaptic inhibition. Perinatal damage to the central nervous system, as it happens in cerebral palsy, leads to pathological reflex response both on segmental and polysegmental levels. It results not only in clinical signs typical for spasticity but also in alterations of brainstem function, such as dysarthria or congenital nystagmus. Selective posterior rhizotomy is a neurosurgical method, routinely used in the treatment of spasticity. The lumbosacral posterior roots are partially cut under perioperative neurophysiological control. The aim of the treatment is the reduction of afferentation for posterior horns resulting in a decrease of pathological reflex responses. Selective posterior rhizotomy consequently decreases lower limbs spasticity. The improvement of upper extremities fine skills, the improvement of speech and cognitive functions has been also observed after selective posterior rhizotomy. The possible pathophysiological explanations of these so-called suprasegmental effects are discussed in the article.

Selective posterior rhizotomy in the treatment of cerebral palsy, first experience in Czech Republic.

BACKGROUND: Selective posterior rhizotomy (SPR) is a surgical treatment of spasticity in patients with cerebral palsy (CP). STARTING POINT: We present the first experience with SPR in Czech Republic. MATERIAL AND METHODS: 14 patients with severe spasticity were indicated for SPR during the period of 2 years (2001-2002). The indication criteria were severe spasticity with clonus, more or less symmetric impairment of lower extremities and increased H/M ratio in preoperative electromyography. SPR was performed in 13 cases, in one patient only the revision and intradural neurolysis of caudal roots was done. In all patients we used osteoplastic laminotomy L2-S1. The intraoperative EMG monitoring with selection of rootlets with abnormal response was performed. Preoperative and postoperative number of spasms, passive range of joint movements, Ashworth scale, Peacock grade and level of functional independence were assessed. The comparison of H/M ratio on EMG before and after surgery was performed. RESULTS: An evident improvement in all tested parameters was noted. The per-operative course in all cases was uneventful. Till now, no persistent complications have been observed. CONCLUSION: SPR improves functional ability in a selected group of CP patients. Our findings regarding clinical outcomes are in agreement with those of other authors. In our experience the extrapyramidal symptoms may not be an absolute contraindication of SPR. (Tab. 5, Fig. 3, Ref. 10.).

Current methods in the treatment of posthemorrhagic hydrocephalus in infants.

The authors reviewed the most recent methods and approaches in the management of posthemorrhagic hydrocephalus in infants. Posthemorrhagic hydrocephalus in infants is associated with a high mortality and morbidity. The incidence of developmental delay, cerebral palsy, epilepsy end visual impairment in surviving children is variable. All treatments have significant drawbacks. Repeated lumbar punctures are frequently associated with high rate of infection and the amount of cerebrospinal fluid drained may be insufficient. External ventricular drainage appears to be more effective than lumbar punctures in evacuating sufficient volumes of cerebrospinal fluid. With subcutaneous reservoir the withdrawal of a sufficient volume of cerebrospinal fluid is achieved, but intermittent elevations of intracranial pressure still occur. Intraventricular fibrinolytic therapy is a promising method in the management of posthemorrhagic hydrocephalus, however more studies with larger numbers of patients are needed. The most common treatment of posthemorrhagic hydrocephalus involves permanent ventricular shunting. Shunts with a programmable valve seem to be superior to other shunt systems. In case of compartmentalization endoscopic procedures are preferred. Conservative treatment with acetazolamide and furosemide does not seem to confer any advantage to the management of posthemorragic hydrocephalus. (Tab. 2, Fig. 2, Ref. 26.)

Craniofacial abnormalities and their relevance for sleep apnoea syndrome aetiopathogenesis in acromegaly.

OBJECTIVE: To explain the effect of craniofacial relations on the development of the sleep apnoea syndrome (SAS) in acromegaly, and to elucidate how the activity of acromegaly affects the severity of SAS. DESIGN: Prospective observational study. METHODS: Cephalometry and sleep ventilation measurements were performed in 26 acromegalic men and in 96 men with SAS. RESULTS: SAS was found in 20 acromegalic men. Compared with non-acromegalic men with SAS, patients with acromegaly and SAS were found to have: enlargement of almost all linear dimensions; increased angle indicating mandibular protrusion; increased difference between maxillary and mandibular protrusion; articular angle decrease; soft palate lengthening; and pharyngeal airway space (PAS) enlargement in the palatal and uvular-tip planes. A comparison of acromegalic men with and without SAS revealed no significant difference in the craniofacial skeleton, although there was a narrowing of the minimal PAS (MinPAS) and of PAS in the uvular-tip plane in patients with SAS. SAS was more frequent in the patients with active acromegaly. MinPAS in the patients with active acromegaly was narrower than in those without disease activity. CONCLUSION: Skeletal abnormalities in acromegalic men with SAS were different from those in SAS patients without acromegaly. Upper airway narrowing due to changes in pharyngeal soft tissues takes a more relevant share in the development of SAS in acromegalic men than skeletal anomalies.

Seizures in sleep apnea patients: occurrence and time distribution.

A retrospective survey of consecutive 480 adult patients (394 men, 96 women, mean age 50.3, SD +/- 10.4 years) with sleep apnea syndrome (SAS) was made in attempt to find out among them the patients with epilepsy. In total 19 subjects (17 men, 2 women, average age 55.8 +/- 8.7 years) representing 4.0% experienced at least two seizures in adult age. The average age at the first seizure was 48.4 +/- 16.1 years. Ten subjects suffered from primarily generalized tonic-clonic seizures, seven from secondarily generalized tonic-clonic seizures, one had complex partial seizures and one simple partial seizures. In 15 subjects (78.9%) the seizures occurred exclusively during sleep. Two patients (11.1%) had seizures exclusively during vigilance and in remaining two subjects the seizures occurred during sleep and vigilance. The findings of high proportion of subjects with epilepsy among SAS subjects, of late seizure onset and of predominantly sleep occurrence of seizures suggest that sleep apnea and hypopnea can facilitate epileptic seizures.

[Sleep apnea syndrome in acromegaly. Treatment and development-- retrospective analysis]. / Spánkový apnoický syndrom (SAS) u akromegalie. Lécení a vývoj--retrospektivní analýza.

In total 56 subjects with acromegaly (37 men and 19 females) were examined in attempt to find sleep apnoea syndrome (SAS). The examination consisted of clinical examination and of all-night monitoring MESAM4 or polyMESAM. The diagnosis of SAS was established in 76.4% of subjects: 31 men and 11 females, average age 51.8 (SD +/- 9.6) years. The average ODI (oxygen desaturation index--number of oxygen saturation drops per 1 hour of sleep) of SAS patients was 29.2 (+/- 20.7). The therapy of SAS was recommended to 27 patients: sleeping position on the side (3 patients), reduction of the weight (8 patients), change of hypnotic drug (1 patient) and CPAP--continuous positive airway pressure (24 patients). CPAP titration was performed in 18 patients (in one subject the titration was repeated 4 years later). CPAP was titrated within all-night polysomnography in 10 subjects and in 9 subjects using self adjusting CPAP. Primary acceptance of CPAP was 94.4%. The average CPAP pressure was 7.8 (+/- 2.1) mbar. The theoretical duration of CPAP use was 546.6 (+/- 533.7) days. Long term compliance was considered as sufficient (weekly 25 hours or more) in 66.7% of patients. Ten patients underwent important acromegaly therapy or its change during the follow up and the improvement or the disappearance of SAS symptoms occurred in 6 of them.