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1.
Oper Dent ; 42(3): 297-307, 2017.
Article in English | MEDLINE | ID: mdl-28467260

ABSTRACT

INTRODUCTION: Limited access to interdental spaces complicates removal of excess material when placing class II composite resin restorations. Evidence-based recommendations on interproximal finishing are rare. We present novel microscalpels for this indication. The aim of the study was to test their fracture strength and cutting ability and to compare microscalpels with the use of a scaler, oscillating devices (G5-ProShape, G5-Proxocare), finishing strips and scalpels of sizes 12, 15, and 21 in a standardized in vitro model. METHODS AND MATERIALS: Fracture strength (LOAD) and cutting forces (CUT) of microscalpels were evaluated at different angles (15, 30, 60, and 75 degrees; n=30 each) in a universal testing machine. Devices were compared in vitro using standardized composite overhangs. Marginal quality (QUAL; n=30) and quantity of excess/deficit (QUAN; n=30) were evaluated using scanning electron microscopy (SEM) for each device (explorative data analysis, Student t-test or analysis of variance; post hoc Scheffé). RESULTS: Microscalpels showed the highest LOAD (95.8 [5.0] N) (mean [standard deviation]) and easiest cutting (CUT) (7.6 [1.5]) at 15 degrees. At all angles, LOAD was significantly higher than CUT (p<0.001). Perfect margins were seen most often with scalpel size 12 (QUAL: 37% relative frequency), while most excess (73.4%) was observed with finishing strips. QUAN was lowest with microscalpels (19.3 [4.4] µm) and highest with finishing strips (116.0 [18.8]). Use of scalers led to fractures and crack formation. CONCLUSION: Microscalpels are able to cut composite at a lower force than necessary to fracture the blades at all angles. Small and/or curved scalpels yield the best-quality margins.


Subject(s)
Composite Resins , Dental Instruments , Dental Polishing/instrumentation , Dental Restoration, Permanent/instrumentation , Dental Bonding , Dental Marginal Adaptation , Equipment Design , In Vitro Techniques , Materials Testing , Microscopy, Electron, Scanning , Surface Properties
2.
Virchows Arch ; 469(3): 339-44, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27392930

ABSTRACT

Purpose of this study was to evaluate prognostic impact of rare variants of urothelial bladder cancer (BC) after treatment with combined radiochemotherapy (RCT). To this end tumour tissue of 238 patients with urothelial carcinoma (UC) treated with transurethral resection of the bladder (TUR-B) and RCT with curative intent was collected. Histomorphological analysis included re-evaluation and semi-quantitative assessment of rare UC subtypes. Additionally, human epidermal growth factor receptor 2 (HER2) chromogenic in situ hybridisation (CISH) was performed in tumours with a micropapillary component exceeding 30 %. Long-term follow-up was available for 200 patients (range 3-282 months). Variant UC histology was found in 45 of 238 tumours, most frequently micropapillary UC (N = 17) including cases with a small fraction of tumour with micropapillary morphology. The mere presence of micropapillary morphology did not affect prognosis. In tumours with extensive (≥30 %) micropapillary morphology (N = 8) Kaplan-Meier analysis revealed significantly worse cancer specific survival (CSS) (P = 0.002) compared to conventional UC (mean survival times 97 months and 229 months, respectively). Univariate Cox regression analysis of cases with ≥30 % micropapillary morphology revealed a hazard ratio of 4.726 (95 % CI 1.629-13.714) for CSS (P = 0.004). CISH revealed HER2 gene amplification in 3/10 tumours with ≥30 % micropapillary component. In conclusion, for BC treated with TUR-B and RCT, the presence of micropapillary morphology in more than 30 % of the tumour is an adverse prognostic factor. Further studies are needed to evaluate a potential benefit of different, especially multimodal treatment strategies for micropapillary UC and also other subtypes of UC. Her2 represents a promising therapeutic target in a subset of micropapillary UC.


Subject(s)
Carcinoma, Papillary/pathology , Carcinoma, Transitional Cell/diagnosis , Carcinoma, Transitional Cell/pathology , Chemoradiotherapy , Urologic Neoplasms/diagnosis , Urologic Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Carcinoma, Papillary/diagnosis , Carcinoma, Papillary/therapy , Chemoradiotherapy/methods , Female , Humans , Male , Middle Aged , Prognosis , Urologic Neoplasms/therapy , Urothelium/pathology
3.
Traffic Inj Prev ; 14(8): 828-34, 2013.
Article in English | MEDLINE | ID: mdl-24073771

ABSTRACT

OBJECTIVE: Histological evaluation of porcine posterior cervical muscles after a forceful translational and extensional head retraction simulating high-speed rear end impact. METHODS: Four anesthetized pigs were exposed to a cervical spine distortion (CSD)-like motion in a lying position. After 2 different survival times of 4 and 6 h (posttrauma), the pigs were euthanized and tissue sampling of posterior cervical muscles was performed. A standard histological staining method involving paraffin-embedded sections was used to analyze the muscles, focusing on injury signs like hemorrhage and inflammatory cell reaction. A pig that was not subjected to impact was used as a control pig and was subjected to the same procedure to exclude any potential artifacts from the autopsy. RESULTS: The differentiation of 8 different posterior neck muscles in the dissection process was successful in more than 50 percent for each muscle of interest. Staining and valid analysis was possible from all extracted samples. Muscle injuries to the deepest posterior neck muscles could be found, especially in the musculus obliquus samples, which showed laminar bleedings in 4 out of 4 samples. In addition, in 4 out of 4 samples we were able to see increased cellular reactions. The splenius muscle also showed bleeding in all 4 samples. All animals showed muscle injury signs in more than three quarters of analyzed neck muscles. Differences between survival times of 4 and 6 h in terms of muscular injury were not of primary interest and could not be found. CONCLUSIONS: By simulating a CSD-like motion we were able to confirm injuries in the posterior cervical muscles under severe loading conditions. Further studies need to be conducted to determine whether these muscle injuries also occur under lower exposure forces.


Subject(s)
Cervical Vertebrae/injuries , Neck Muscles/injuries , Neck Muscles/pathology , Whiplash Injuries/pathology , Acceleration , Accidents, Traffic/statistics & numerical data , Animals , Case-Control Studies , Disease Models, Animal , Male , Swine
4.
Zootaxa ; 3620: 301-50, 2013.
Article in English | MEDLINE | ID: mdl-26120712

ABSTRACT

Specimens from across the range of the Hyperolius nasutus species group were sequenced for two mitochondrial genes and one nuclear gene. Advertisement calls were recorded from the same specimens where possible, and morphological characters were compared. Bayesian inference and maximum likelihood produced a tree indicating 16 clades. The clades show little or no overlap in combinations of 16S sequence difference, shared tyr haplotypes, advertisement call parameters, snout profiles and webbing. On the basis of these data we recognise H. acuticeps, H. adspersus, H. benguellensis, H. dartevellei, H. igbettensis, H. nasutus, H. nasicus, H. poweri, H. viridis and describe six new species: Hyperolius friedemanni sp. nov. Mercurio & Rödel, Hyperolius howelli sp. nov. Du Preez & Channing, Hyperolius inyangae sp. nov. Channing, Hyperolious jacobseni sp. nov. Channing, Hyperolius rwandae sp. nov. Dehling, Sinsch, R6del & Channing, and Hyperolius lupiroensis sp. nov. Channing. Hyperolius lamottei is confirmed to be outside the H. nasutus group clade. Hyperolius granulatus, H. oxyrhynchus, H. punctulatus and H. sagitta are assigned as junior synonyms. As our results are based on a small number of specimens, these hypotheses await testing with larger sample sizes and more characters. A species distribution model suggests where outlier populations might be found.


Subject(s)
Amphibian Proteins/genetics , Anura/classification , Anura/genetics , Vocalization, Animal , Africa , Animal Distribution , Animals , Anura/anatomy & histology , Anura/physiology , Cell Nucleus/genetics , Female , Male , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA , Sound Spectrography , Species Specificity
5.
Georgian Med News ; (154): 47-52, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18323594

ABSTRACT

In 2003 Georgian Parliament restricted smoking in all healthcare facilities to designated smoking areas. Observed compliance has been low. This quantitative study of airborne nicotine and particulate concentrations in nine healthcare facilities in Tbilisi and Region Kakheti in February, 2007 was a pilot to assess the degree of noncompliance with the law and to identify potential strategies for increasing compliance. Passive sampling of nicotine and active sampling of PM(2.5) in selected healthcare facilities. None of the facilities we monitored had designated smoking areas that met the legal requirements. Fifty of the 51 samplers registered concentrations of nicotine above the level of detection. Of these, 52% showed concentrations below 1 microg/m(3) nicotine, 27% showed concentrations between 1 and 5 microg/m(3) and 20% were above 5 microg/m(3). The highest nicotine levels were found in medical staff offices, and in undesignated "informal smoking areas". These data support qualitative observations that the law restricting smoking in Georgian healthcare facilities to designated areas is poorly enforced and does not protect patients and employees from secondhand smoke. These findings suggest that Georgian law should be changed to make all healthcare institutions smoke free environments and that there is a need for tobacco control programs targeted at medical professionals in Georgia.


Subject(s)
Guideline Adherence , Health Facilities/legislation & jurisprudence , Health Promotion/legislation & jurisprudence , Smoking Cessation/legislation & jurisprudence , Smoking Prevention , Ganglionic Stimulants/blood , Georgia (Republic) , Health Personnel , Humans , Nicotine/blood , Pilot Projects , Prevalence , Public Policy , Tobacco Smoke Pollution/analysis
6.
J Neural Transm (Vienna) ; 113(7): 869-76, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16252068

ABSTRACT

As the enzyme dopamine-beta-hydroxylase (DbetaH) converts dopamine to norepinephrine and both transmitters seem to be involved in the pathology of alcoholism and severe alcohol withdrawal symptoms, the gene encoding DbetaH (DBH) was applied to explore the genetic background of alcoholism and severe withdrawal symptoms. 102 healthy control subjects and 208 alcoholics, including 97 patients with a history of mild withdrawal symptoms, 57 with a history of alcohol withdrawal seizure (AWS) and 82 with a history of delirium tremens (DT) were genotyped for the DBH*444G/A polymorphism revealing a significantly elevated frequency of genotypes carrying the A-allele (p = 0.02; after Bonferroni adjustment for multiple tests) in alcoholics compared to healthy controls. Frequencies of alleles and genotypes of individuals with mild withdrawal symptoms did not differ significantly from those of patients with DT or AWS.


Subject(s)
Alcohol-Induced Disorders, Nervous System/genetics , Alcoholism/genetics , Dopamine beta-Hydroxylase/genetics , Genetic Predisposition to Disease/genetics , Polymorphism, Genetic/genetics , Substance Withdrawal Syndrome/genetics , Adult , Alcohol Withdrawal Delirium/enzymology , Alcohol Withdrawal Delirium/genetics , Alcohol Withdrawal Delirium/physiopathology , Alcohol-Induced Disorders, Nervous System/enzymology , Alcohol-Induced Disorders, Nervous System/physiopathology , Alcoholism/enzymology , Alcoholism/physiopathology , Brain/drug effects , Brain/enzymology , Brain/physiopathology , Catecholamines/biosynthesis , Central Nervous System Depressants/adverse effects , DNA Mutational Analysis , Ethanol/adverse effects , Female , Gene Frequency/genetics , Genetic Testing , Genotype , Humans , Male , Middle Aged , Substance Withdrawal Syndrome/enzymology , Substance Withdrawal Syndrome/physiopathology
7.
Tob Control ; 14(6): 396-404, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16319363

ABSTRACT

BACKGROUND: Exposure to secondhand smoke causes lung cancer; however, there are little data in the open literature on the in vivo toxicology of fresh sidestream cigarette smoke to guide the debate about smoke-free workplaces and public places. OBJECTIVE: To investigate the unpublished in vivo research on sidestream cigarette smoke done by Philip Morris Tobacco Company during the 1980s at its Institut für Biologische Forschung (INBIFO). METHODS: Analysis of internal tobacco industry documents now available at the University of California San Francisco Legacy Tobacco Documents Library and other websites. RESULTS: Inhaled fresh sidestream cigarette smoke is approximately four times more toxic per gram total particulate matter (TPM) than mainstream cigarette smoke. Sidestream condensate is approximately three times more toxic per gram and two to six times more tumourigenic per gram than mainstream condensate by dermal application. The gas/vapour phase of sidestream smoke is responsible for most of the sensory irritation and respiratory tract epithelium damage. Fresh sidestream smoke inhibits normal weight gain in developing animals. In a 21 day exposure, fresh sidestream smoke can cause damage to the respiratory epithelium at concentrations of 2 microg/l TPM. Damage to the respiratory epithelium increases with longer exposures. The toxicity of whole sidestream smoke is higher than the sum of the toxicities of its major constituents. CONCLUSION: Fresh sidestream smoke at concentrations commonly encountered indoors is well above a 2 microg/m3 reference concentration (the level at which acute effects are unlikely to occur), calculated from the results of the INBIFO studies, that defines acute toxicity to humans. Smoke-free public places and workplaces are the only practical way to protect the public health from the toxins in sidestream smoke.


Subject(s)
Air Pollutants/toxicity , Hazardous Substances/toxicity , Tobacco Smoke Pollution/adverse effects , Air Pollutants/analysis , Animals , Hazardous Substances/analysis , Humans , Inhalation Exposure/adverse effects , Mice , No-Observed-Adverse-Effect Level , Rats , Skin Neoplasms/etiology , Tobacco Industry , Tobacco Smoke Pollution/analysis
8.
J Neural Transm (Vienna) ; 109(11): 1423-9, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12454738

ABSTRACT

Neuropeptide Y (NPY) modulates ethanol drinking in rodents. The C-allele of the T1128C polymorphism of the human NPY gene has been previously associated with elevated alcohol consumption in a Finn population study. The present study tested the hypothesis that the T1128C polymorphism is associated with the diagnosis of alcoholism or with severe forms of alcohol withdrawal and with the daily consumption of alcohol in alcoholic patients. After PCR-RFLP genotyping, two groups of alcoholics with severe withdrawal symptoms (delirium tremens, n = 83; withdrawal seizures, n = 65) were compared to alcoholics with mild withdrawal symptoms (n = 97). An elevated frequency of the C-allele in the individuals with severe withdrawal symptoms was found, however not reaching statistical significance. Further a group of healthy controls (n = 102) was compared to all included alcoholics (n = 216) revealing no significant result. Alcoholics carrying the C-allele reported a non significantly elevated daily consumption of alcohol compared to alcoholics with the TT genotype. All alcohol dependent subjects with severe withdrawal symptoms revealed a significantly elevated daily consumption of alcohol compared to alcoholics with only mild withdrawal symptoms. More studies on different ethnic groups are needed to further elucidate the influence of the NPY gene on alcoholism.


Subject(s)
Alcoholism/genetics , Neuropeptide Y/genetics , Polymorphism, Genetic , Substance Withdrawal Syndrome/diagnosis , Substance Withdrawal Syndrome/genetics , Adult , Alcohol Withdrawal Delirium/diagnosis , Alcohol Withdrawal Delirium/genetics , Alleles , Case-Control Studies , Cysteine/genetics , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Middle Aged , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Severity of Illness Index , Threonine/genetics
9.
Dig Surg ; 19(1): 65-6, 2002.
Article in English | MEDLINE | ID: mdl-11961360

ABSTRACT

A 64-year-old man with Muir-Torre syndrome (MTS), a condition characterized by the association of multiple sebaceous tumours and kerato-acanthomas with internal malignancies, developed a carcinoma of the ampulla of Vater. This is the 2nd reported ampullary carcinoma in 205 reported cases of MTS, suggesting a higher prevalence in MTS patients than in the general population. As an ampullary carcinoma is potentially amenable to surgical resection, particularly when detected early, patients with MTS should undergo regular endoscopic surveillance of the ampulla of Vater.


Subject(s)
Ampulla of Vater/pathology , Common Bile Duct Neoplasms/diagnosis , Keratoacanthoma/diagnosis , Sebaceous Gland Neoplasms/diagnosis , Ampulla of Vater/surgery , Common Bile Duct Neoplasms/secondary , Common Bile Duct Neoplasms/surgery , Humans , Keratoacanthoma/surgery , Male , Middle Aged , Pancreaticoduodenectomy , Sebaceous Gland Neoplasms/surgery , Syndrome , Treatment Outcome
10.
Brain Res Cogn Brain Res ; 12(1): 167-70, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11489620

ABSTRACT

We investigated the spatiotemporal cortical dynamics during the perception of object-motion and visually-induced self-motion perception in six normal subjects, using a 143-channel neuromagnetometer. Object-motion specific tasks evoked early transient activity over the right temporooccipital cortex, while self-motion perception, or vection, additionally was followed by sustained bilateral activity in the temporoparietal area. The specific signal distributions suggest to represent the different perceptual modes of object-motion and self-motion sensation.


Subject(s)
Cerebral Cortex/physiology , Motion Perception/physiology , Visual Perception/physiology , Adult , Head Movements/physiology , Humans , Magnetoencephalography , Male , Occipital Lobe/physiology , Temporal Lobe/physiology
11.
Radiology ; 220(1): 186-9, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11425994

ABSTRACT

PURPOSE: To evaluate whether dental computed tomography (CT) can depict the frequency, diameter, position, and direction of vessels entering the mandible through lingual bone canals. MATERIALS AND METHODS: Thirty-two consecutive patients underwent preimplantation CT of the lower jaw and examination for the presence, number, location, diameter, and direction of lingual canals entering the mandible. In addition, three cadaver mandibles were investigated with dental CT and subsequently dissected to confirm the CT findings. RESULTS: All patients demonstrated at least one lingual vascular canal, and 20 (63%) had multiple (two to five) canals. The typical lingual canal locations were the midline of the mandible and the premolar region. The mean diameter of the lingual canals was 0.7 mm +/- 0.3 (SD) (range, 0.4--1.5 mm) in the midline and 0.6 mm +/- 0.2 (range, 0.3--1.2 mm) in both premolar regions of the mandible. Examination results in the three cadaver mandibles confirmed the CT findings in those mandibles. CONCLUSION: Dental CT can depict the occurrence, position, and size of the lingual vascular canals of the mandible. Radiologists should be aware of this anatomic feature and its possible implications.


Subject(s)
Mandible/blood supply , Mandible/diagnostic imaging , Radiography, Dental/methods , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Cadaver , Dental Implantation, Endosseous , Female , Humans , Male , Mandible/anatomy & histology , Middle Aged , Preoperative Care , Regional Blood Flow , Sensitivity and Specificity
12.
Magn Reson Imaging ; 18(6): 635-40, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10930772

ABSTRACT

The purpose of this study was to compare the diagnostic efficacy of a newly developed T(1)-weighted three-dimensional segmented echo planar imaging (3D EPI) sequence versus a conventional T(1)-weighted three dimensional spoiled gradient echo (3D GRE) sequence in the evaluation of brain tumors. Forty-four patients with cerebral tumors and infections were examined on a 1.0 T MR unit with 23 mT/m gradient strength. The total scan time for the T(1) 3D EPI sequence was 2 min 12 s, and for a conventional 3D GRE sequence it was 4 min 59 s. Both sequences were performed after administration of a contrast agent. The images were analyzed by three radiologists. Image assessment criteria included lesion conspicuity, contrast between different types of normal tissue, and image artifacts. In addition, signal-to-noise and contrast-to-noise-ratio (C/N) were calculated. The gray-white differentiation and C/N ratio of 3D EPI were found to be inferior to conventional 3D GRE images, but the difference was not statistically significant. In the qualitative comparison, lesion detection and conspicuity of 3D EPI images and conventional 3D GRE images were similar, but a tow-fold reduction of the scanning time was obtained. With the 3D EPI technique, a 50% scan time reduction could be achieved with acceptable image quality compared to conventional 3D GRE. Thus, the 3D EPI technique could replace conventional 3D GRE in the preoperative imaging of brain.


Subject(s)
Brain Neoplasms/diagnosis , Echo-Planar Imaging/methods , Adult , Female , Humans , Male , Preoperative Care
13.
J Magn Reson Imaging ; 11(6): 665-72, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10862066

ABSTRACT

The purpose of this study was to compare the diagnostic sensitivity of unenhanced magnetic resonance (MR) imaging, and MR imaging with a new superparamagnetic iron oxide (SPIO)-enhanced contrast agent (SHU 555 A) with biphasic helical computed tomography during arterial portography (CTAP) in patients with focal liver lesions. Eighteen patients with a total of 91 (78 malignant, 13 benign) proven liver lesions underwent unenhanced short tau inversion recovery (STIR), T2-weighted (T2-w) TSE, and SHU 555 A-enhanced T2-w turbo spin-echo (TSE) MR imaging and biphasic helical CTAP. The standard of reference was histopathologic analysis of resected specimens in 59 lesions, intraoperative ultrasound with biopsy in 20 lesions, and CT-guided biopsy and follow-up in 12 lesions. Diagnostic performance of the imaging modalities was compared quantitatively and qualitatively by assessing lesion involvement in liver segments. There were 68 lesions detected on unenhanced T2-w TSE, which resulted in a sensitivity of 75%. With the STIR sequence, 76 lesions were detected, for a sensitivity of 84%, and with SHU 555 A-enhanced MRI, 84 lesions were detected, for a sensitivity of 92%. CTAP detected 88 lesions, for a sensitivity of 97%. The accuracy for unenhanced T2-w TSE was 98%, for STIR 99%, for enhanced-MRI 100%, and for CTAP 95%. The specificity was 100% for SHU 555 A-enhanced MRI and 95% for CTAP. SHU 555 A-enhanced MRI was superior to nonenhanced MRI (P < 0.05) and equivalent to CTAP in terms of sensitivity. Due to the absence of false-positive results on SHU 555 A-enhanced MRI, the specificity and accuracy of enhanced MRI were higher than those of CTAP, but the difference was not statistically significant (P = 0.134).


Subject(s)
Contrast Media , Image Enhancement/methods , Iron , Liver Neoplasms/diagnosis , Liver/pathology , Magnetic Resonance Imaging/methods , Oxides , Tomography, X-Ray Computed/methods , Adult , Aged , Analysis of Variance , Confidence Intervals , Dextrans , Female , Ferrosoferric Oxide , Humans , Liver Neoplasms/pathology , Magnetite Nanoparticles , Male , Middle Aged , Portal Vein/diagnostic imaging , Portal Vein/pathology , Probability , Sensitivity and Specificity
14.
Magn Reson Imaging ; 18(3): 237-43, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10745131

ABSTRACT

The purpose of this study was to compare the diagnostic efficacy of single shot fast spin echo sequence (SSh-FSE), and single shot GRASE-sequence (SSh-GRASE) to the conventional T(2)-weighted fast spin echo-sequence (T(2)-FSE) in the imaging of brain disorders. Thirty three patients with high signal intensity lesions on T(2)-weighted images (n = 28), or intracerebral hemorrhage (n = 5), were examined on a 1.0 T MR scanner, with 23 mT/m gradient strength. The scan time for the conventional T(2)-FSE-sequence was 2 min 57 s, the scan time for the single shot-FSE-, and single shot-GRASE-sequences was 11 sec, and 17 sec, respectively. Twenty-one patients remained still during the examination, whereas 12 could not stay still with consecutive marked motion artifacts. Images were reviewed by three radiologists. Lesion conspicuity, image quality, and artifacts were scored on a subjective scale. Signal-to-noise ratios of lesions and normal tissue and contrast-to-noise ratios (CNR) were measured by region of interest (ROI). In the patient group without motion artifacts conspicuity for lesions > or =5 mm did not show a significant difference on conventional T(2)-FSE, single shot-FSE and single shot-GRASE. Detectability of the smaller lesions was significantly inferior on single shot-FSE-, and single shot-GRASE-sequences in artifact free images. For the patient group with motion artifacts SSh-FSE and SSh-GRASE were markedly superior to the conventional T(2)-FSE. Grey-white differentiation was better on conventional T(2)-FSE. Physiologic ferritin as well as pathologic hemosiderin depositions were slightly darker and therefore better visible on SSh-GRASE than on SSh-FSE. Conventional T(2)-FSE showed significantly more artifacts. In conclusion, SSh-FSE and SSh-GRASE imaging can be used for rapid imaging of the brain in those patients who are claustrophobic or in patients with involuntary movements due to extrapyramidal disorders, as well as in children in whom anesthesia is contraindicated or sedation is not possible.


Subject(s)
Brain Diseases/diagnosis , Brain/pathology , Magnetic Resonance Imaging/methods , Adolescent , Adult , Aged , Artifacts , Brain Chemistry , Brain Neoplasms/diagnosis , Child , Child, Preschool , Female , Hemosiderin/analysis , Humans , Huntington Disease/diagnosis , Image Enhancement/methods , Magnetic Resonance Imaging/psychology , Male , Middle Aged , Motion , Multiple Sclerosis/diagnosis , Sensitivity and Specificity , Time Factors
15.
J Comput Assist Tomogr ; 24(2): 288-92, 2000.
Article in English | MEDLINE | ID: mdl-10752895

ABSTRACT

Three patients with histologically proven elastofibroma dorsi underwent MRI, using T1-weighted, T2-weighted, STIR (short inversion time inversion recovery), and contrast-enhanced SE sequences. All lesions typically displayed low signal intensity masses interspersed with areas of high signal intensity on T1- and T2-weighted SE images. Contrary to prior reports, two patients showed marked enhancement of the mass after administration of Gd-DTPA. Although the characteristic signal intensity on conventional T1- and T2-weighted images may lead to the early diagnosis of this rare tumor, radiologists should be aware that marked contrast enhancement may be representative in elastofibroma dorsi.


Subject(s)
Fibroma/diagnosis , Image Enhancement/methods , Scapula/pathology , Shoulder/pathology , Female , Fibroma/surgery , Gadolinium DTPA , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Shoulder/surgery
16.
Clin Orthop Relat Res ; (364): 213-9, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10416411

ABSTRACT

Two cases of elastofibroma dorsi (one bilateral, one unilateral) in the periscapular and infrascapular region of two male patients are described. Magnetic resonance imaging revealed a tumorous mass of typical low signal intensity with interspersed areas of high signal intensity on T1 and T2 weighted spin echo sequences. In contrast to previous studies that reported mild enhancement within elastofibromas after administration of intravenous contrast agent, marked enhancement in one of two elastofibromas was found. This is considered to be atypical for benign lesions. After biopsy and histopathologic examination, an intended marginal resection was performed in both cases. Laboratory values, radiographs, and computed tomography may not be helpful in differentiating elastofibroma from malignant tumors. In addition to careful clinical investigation, magnetic resonance imaging is the method of choice leading to a presumptive diagnosis. Because marked enhancement on contrast agent images was observed, which is characteristic for malignant tumors, one should be aware that this feature does not exclude the presence of elastofibroma. Accurate diagnosis should be made preferably by biopsy and histopathologic evaluation before additional treatment is administered. Marginal resection is curative in patients with symptoms. Despite its low incidence, this pseudotumoral lesion should be known generally to differentiate it from malignant tumors and to avoid unnecessary wide or radical surgery.


Subject(s)
Back , Fibroma/diagnosis , Magnetic Resonance Imaging , Scapula , Soft Tissue Neoplasms/diagnosis , Biopsy , Diagnosis, Differential , Fibroma/etiology , Fibroma/surgery , Humans , Male , Middle Aged , Soft Tissue Neoplasms/etiology , Soft Tissue Neoplasms/surgery , Tomography, X-Ray Computed
18.
Neuroradiology ; 41(4): 283-7, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10344516

ABSTRACT

Virchow-Robin spaces (VRS) are pia-lined extensions of the subarachnoid space which surround penetrating arteries as they enter the brain on its surface. Using high-resolution MRI, which shows small penetrating arteries, we studied a possible association of accentuated VRS in children with tension-type headache (TTH) or migraine. We studied 58 children aged 3-14 years (mean 10.8 years) with a clinical diagnosis of migraine (31) or TTH (27), who underwent cerebral MRI, and 30 headache-free patients of the same age (mean 10.2 years) and 30 adult migraineurs with postpubertal onset of symptoms, who served as controls. The images were reviewed for structural abnormalities in the regions of the small penetrating arteries. Accentuated VRS were found in 61% of the children with migrainous headaches and in 22% of children of those with TTH. Prominent VRS were seen in 27% of the control children and in only 13% of the adults. Small infarcts and gliosis were rare in children with or without headache, but were seen in 30% of the adult migraineurs. Our findings show that accentuated VRS are significantly more common in children with migraine than in those with TTH or headache-free controls. Detection of accentuated VRS may therefore enhance differential diagnosis of primary headaches in children, contributing to an improvement in management.


Subject(s)
Brain/blood supply , Migraine Disorders/pathology , Pia Mater/pathology , Tension-Type Headache/pathology , Adolescent , Adult , Age Factors , Arteries/pathology , Arterioles/pathology , Cerebral Infarction/diagnosis , Cerebral Infarction/pathology , Chi-Square Distribution , Child , Child, Preschool , Diagnosis, Differential , Female , Gliosis/diagnosis , Gliosis/pathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Subarachnoid Space/pathology
19.
Radiology ; 210(3): 871-5, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10207495

ABSTRACT

The authors compared image quality and stability with a dry laser imager versus a conventional wet laser imager. Hard copies of 56 magnetic resonance imaging and computed tomographic studies were analyzed for gray-scale distribution and temperature stability. Results with the dry laser imager did not reach the quality of results with a wet laser imager, but the performance and ecologic criteria were sufficient to make use of this technique advantageous.


Subject(s)
Lasers , Magnetic Resonance Imaging , Printing/instrumentation , Tomography, X-Ray Computed , Calibration , Densitometry , Humans , Image Enhancement , Observer Variation , Radiographic Image Enhancement , Reproducibility of Results
20.
Rofo ; 170(1): 16-21, 1999 Jan.
Article in German | MEDLINE | ID: mdl-10071639

ABSTRACT

PURPOSE: To compare the diagnostic value of high definition macroradiography and MRI in patients with the suspicion of occult wrist fractures. MATERIALS AND METHODS: In a prospective study, 23 patients with clinically suspected wrist fractures and normal initial plain radiographs underwent high resolution macroradiography and MR imaging shortly after trauma. Macroradiographs were taken with a microfocus tube using an anode of 0.03-0.3 mm providing a 4x magnification of the wrist, which was obtained in 4 projections. MR images were performed on a 1.0 T MR unit in coronal planes using T1 weighted SE, T2.-weighted 3D GE, and Turbo-STIR sequences. Follow-up radiographs after 6 weeks were used to confirm the diagnosis of a primary occult wrist fracture. RESULTS: Macroradiography depicted 5 wrist fractures: 4 fractures of the scaphoid bone and 1 fracture of the capitate bone. MRI demonstrated 11 fractures (one of them false-positive): 9 fractures of the scaphoid bone and two fractures of the capitate bone. Using macroradiography, the sensitivity for the detection of occult fractures of the wrist was 50% with a specificity of 100%, using MRI the sensitivity was 100% with a specificity of 92%. CONCLUSION: MRI seems to be superior to high resolution macroradiography in the detection of occult scaphoid fractures and thus is recommended in the management of patients with clinically suspected scaphoid fractures not evident on initial plain films.


Subject(s)
Carpal Bones/injuries , Fractures, Bone/diagnostic imaging , Magnetic Resonance Imaging , Radiographic Image Enhancement , Radiographic Magnification , Wrist Injuries/diagnostic imaging , Adolescent , Adult , Carpal Bones/diagnostic imaging , Child , Female , Humans , Male , Middle Aged , Sensitivity and Specificity
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