[Update: Clinical imaging of cartilage-part 2 : Aspects helpul in daily clinical practice]. / Update: Klinische Knorpelbildgebung ­ Teil 2 : In der Klinik hilfreiche Aspekte.

BACKGROUND: Imaging-based analysis of articular cartilage and its defects as well as the radiologist have to live up to the more and more specific clinical questions arising from increasing experience with cartilage-dedicated therapies. MATERIALS AND METHODS: Based on the currently available literature and experience from clinical routine, imaging findings relevant for lesion analysis will be summarized and illustrated by specific pathologies. RESULTS: Local aspects and topographic distribution of bone marrow edema pattern (BMEP), careful analysis of the cartilage surface and of the subchondral plate as well as the patient's clinical and biomechanical context are essential for image analysis. Formal grading is helpful to communicate imaging findings, but in itself is not sufficient for a comprehensive analysis. Assessing the stability of a lesion is important for therapy planning. Imaging is helpful to this end, but can be challenging and requires consideration of the arthroscopic and histologic perspective especially when dealing with juvenile osteochondral lesions. DISCUSSION: In order to maximize the therapeutic and prognostic relevance of findings from cartilage imaging, radiologists need to be sensitive to-often very subtle-imaging clues but at the same time we need to be aware of the limitations of our methods.

[Update: clinical imaging of cartilage-part 1 : Technical aspects]. / Update: Klinische Knorpelbildgebung ­ Teil 1 : Technische Aspekte.

BACKGROUND: In order to answer clinical therapy-oriented questions, reliable and consistent depiction of articular cartilage across technical platforms is necessary. MATERIALS AND METHODS: Technical standards and developments in cartilage imaging are summarized based on current literature and experience from clinical daily routine. RESULTS: Clinical questions that need to be answered relate to cross-sectional extent, depth, differentiating cartilaginous from bony components of a lesion and to the lesion's location within the compartment. If present, displaced fragments, concomitant meniscal, ligamentous and/or degenerative lesions should be identified. To date, magnetic resonance imaging (MRI) is the workhorse of cartilage imaging and is largely based on moderately T2-weighted and also proton-density (PD)-weighted fat-suppressed turbo-spin-echo sequences. Direct MR- and CT-arthrography are the gold standard to evaluate thin cartilage layers. Recent advances in coil and MR sequence design, increased availability of 3T-MR scanners and more and more sophisticated acceleration techniques allow for better spatial resolution and more robust image contrast at acceptable scan times. DISCUSSION: As abundant as current developments in clinical routine cartilage imaging may be, the radiologist must carefully select the approach best suited to answering the clinical questions.

Primary wound closure with a Limberg flap vs. secondary wound healing after excision of a pilonidal sinus: a multicentre randomised controlled study.

PURPOSE: Off-midline procedures seem to be the best method of primary wound closure after excision of a pilonidal sinus. Primary wound closure with a Limberg flap was compared to secondary wound healing. METHODS: From January 2006 to July 2012, 102 patients with given informed consent (mean age 28 years, men 81%) who had excision of a pilonidal sinus in three hospitals in Switzerland were randomised to group L (Limberg flap, n = 51) or to group E (excision only, n = 51). Primary endpoint was duration of incapacity for work. Follow-up was at 3 weeks and at 1 year postoperative (95% follow-up). RESULTS: Both groups were comparable with regard to patient characteristics. The median (range) operation time was 60 (30-80) min in group L vs. 30 (10-75) min in group E (p < 0.001). No significant differences were found in postoperative pain and painkiller intake; pain, percentage of patients at work and overall satisfaction at 3 weeks postoperative; and overall duration of incapacity for work and overall satisfaction at 1-year follow-up. The complication rate was 49% in group L vs. 12% in group E (p < 0.001). Complications in group L were seroma (6%), wound dehiscence (45%), skin necrosis (10%), hematoma (6%), infection (4%) and recurrent disease (13%). Complications in group E were recurrent disease (6%) and wound healing disorder (6%). CONCLUSIONS: After excision of a pilonidal sinus, primary wound closure with a Limberg flap has no advantage over secondary wound healing. The main reason for this conclusion is the relatively high complication rate of primary wound closure with a Limberg flap.

Impact of two extubation techniques on the intra-abdominal pressure: a preliminary study.

PURPOSE: High pressure peaks might be a risk factor for the development of abdominal hernia. The course of abdominal pressure during extubation remains unclear. This preliminary study assessed the impact of two established extubation techniques. METHODS: Twenty-four consecutive patients suffering from abdominal wall hernia with the indication for surgical treatment were included. Twelve patients were extubated directly after the intravenous anaesthesia was stopped, before they had spontaneous breathing (deep extubation). The other 12 were extubated after they had spontaneous breathing (awake extubation). Intra-abdominal pressure (IAP) was measured via bladder catheter continuously. RESULTS: The highest value during extubation as well as the main increase in IAP was significantly lower in patients who underwent deep extubation (p < 0.001). CONCLUSIONS: Therefore, this extubation technique might improve the outcome of hernia repair.

[Detection and evaluation of cartilage defects in the canine stifle joint - an ex vivo study using high-field magnetic resonance imaging]. / Ex-vivo-Untersuchungen zum Nachweis von Knorpeldefekten im Kniegelenk des Hundes mit der Hochfeld-Magnetresonanztomographie.

OBJECTIVE: The aim of our study was to implement and test an imaging protocol for the detection and evaluation of standardised cartilage defects using high-field magnetic resonance imaging (MRI) and to determine its limitations. MATERIAL AND METHOD: A total of 84 cartilage defects were created in the femoral condyles of euthanized dogs with a minimum body mass of 25 kg. The cartilage defects had a depth of 0.3 to 1.0 mm and a diameter of 1 to 5 mm. T1-FLASH-3D-WE-sequences with an isotropic voxel size of 0.5 x 0.5 x 0.5 mm and an anisotropic voxel size of 0.3 x 0.3 x 0.8 mm were used. In addition to quantitative evaluation of the cartilage defects, the sig- nal intensities, signal-to-noise ratios and contrast-to-noise ratios of the cartilage were determined. Of special interest were the limita- tions in identifying and delineating the standardised cartilage defects. RESULTS: With the anisotropic voxel size, more cartilage defects were detectable. Our results demonstrated that cartilage defects as small as 3.0 mm in diameter and 0.4 mm in depth were reliably detected using anisotropic settings. Cartilage defects below this size were not reliably detected. CONCLUSION AND CLINICAL RELEVANCE: We found that for optimal delineation of the joint cartilage and associated defects, a higher in-plane resolution with a larger slice thickness should be used, corresponding to the anisotropic settings employed in this study. For the delineation of larger cartilage defects, both the anisotropic and isotropic imaging methods can be used.

Treatment of rare co-occurrence of Epstein-Barr virus-driven post-transplant lymphoproliferative disorder and hemophagocytic lymphohistiocytosis after allogeneic stem cell transplantation.

In both conditions, post-transplant lymphoproliferative disorder (PTLD) and hemophagocytic lymphohistiocytosis (HLH), infection with Epstein-Barr virus (EBV) is a key mechanism: almost all PTLD in allogeneic stem cell transplantation (alloSCT) is caused by EBV-related neoplastic lymphoproliferation, and secondary HLH is most frequently triggered by EBV infection. Therefore, concomitant EBV-driven PTLD and HLH early after alloSCT require an approach to eliminate EBV and balance immune activation simultaneously. We report on a patient who developed simultaneous PTLD and signs of HLH on day 64 after alloSCT. Treatment was comprised of stopping cyclosporine, short-course dexamethasone, and 3 courses of rituximab. The patient showed full recovery and complete remission of lymphadenopathy. This result indicates that immediate reduction in EBV-carrying B cells by rituximab, suppression of general inflammation, and parallel support of reconstitution of long-term T-cell function, might be an appropriate therapeutic approach in this rare situation.

[Post-treatment rehabilitation after autologous chondrocyte implantation: State of the art and recommendations of the Clinical Tissue Regeneration Study Group of the German Society for Accident Surgery and the German Society for Orthopedics and Orthopedic Surgery]. / Nachbehandlung bei der autologen Chondrozytentransplantation: Eine Bestandsaufnahme und Empfehlung der AG Klinische Geweberegeneration der DGU/DGOOC.

BACKGROUND: Over the course of the past two decades autologous chondrocyte implantation (ACI) has become an important surgical technique for treating large cartilage defects. The original method using a periostal flap has been improved by using cell-seeded scaffolds for implantation, the matrix-based autologous chondrocyte implantation (mb-ACI) procedure. MATERIAL AND METHODS: Uniform nationwide guidelines for post-ACI rehabilitation do not exist. A survey was conducted among the members of the clinical tissue regeneration study group concerning the current rehabilitation protocols and the members of the study group published recommendations for postoperative rehabilitation and treatment after ACI based on the results of this survey. RESULTS: There was agreement on fundamentals concerning a location-specific rehabilitation protocol (femoral condyle vs. patellofemoral joint). With regard to weight bearing and range of motion a variety of different protocols exist. Similar to this total agreement on the role of magnetic resonance imaging (MRI) for postsurgical care was found but again a great variety of different protocols exist. CONCLUSIONS: This manuscript summarizes the recommendations of the members of the German clinical tissue regeneration study group on postsurgical rehabilitation and MRI assessment after ACI (level IVb/EBM).

A new method to analyze dGEMRIC measurements in femoroacetabular impingement: preliminary validation against arthroscopic findings.

OBJECTIVE: To validate a new method to analyze delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) measurements in the hip for early assessment of cartilage defects in femoroacetabular impingement (FAI). METHODS: We performed a retrospective review of 10 hips in 10 FAI patients, who underwent hip arthroscopy. T1-weighted images and dGEMRIC T(1) maps were acquired at 1.5 T on coronal planes, including the anterior-superior, superior, posterior-superior hip cartilage. For all slices, a region of interest (ROI) was defined over the central portion of the femoral cartilage, assumed to be healthy, and T1 values (x) were transformed to standard scores (z) using z = (x -µ)/σ, where µ and σ are the average and standard deviation of T1 in the femoral ROI. Diagnostic performance of the resulting standardized dGEMRIC maps was evaluated against intraoperative findings and compared with that of a previously proposed dGEMRIC analysis as well as morphologic assessment. RESULTS: Assuming z = -2 or z = -3 as the threshold between normal and degenerated cartilage, sensitivity, specificity and accuracy were 88%, 51% and 62%, and 71%, 63% and 65%, respectively. By using T1 = 500 ms as single threshold for all dGEMRIC T1 maps, these values became 47%, 58% and 55%, whereas they were 47%, 79% and 70% for morphologic evaluation. CONCLUSIONS: Standardized dGEMRIC can increase the sensitivity in detecting abnormal cartilage in FAI and has the potential to improve the clinical interpretation of dGEMRIC measurements in FAI, by removing the effect of inter- and intra-patient T1 variability.

Development and validation of a new method for the radiologic measurement of the tibial slope.

PURPOSE: The posterior tibial slope has a huge influence on the kinematics of the knee. In several orthopedic interventions such as high tibial osteotomy and unicondylar or bicondylar knee replacement changing, the tibial slope can result in altered knee mechanics. Therefore, an exact preoperative measurement of the posterior tibial slope is mandatory. Several methods are used on conventional radiographs and CT scans, but until now there is no standard validated method. The aim of this study was to compare several methods and imaging techniques to measure the posterior tibial slope and to establish a standard and reliable measurement method by radiography. METHODS: Fourteen knees (seven cadavers) were scanned by a 64-slice CT, a 3T-MRI, and true lateral radiographs were performed. The anatomical references (TPAA = tibial proximal anatomical axis; ATC = anterior tibial cortex; PTC = posterior tibial cortex) and the new computed reference (MPA = mean of PTA and ATC) were compared by short as well as long radiographs, CT scan and MRI. The influence of a malrotation in radiographs of the knees was also analyzed. RESULTS: CT scan and MRI are suitable for the measurement of the medial and lateral posterior tibial slopes, the results of the radiographs varied depending on the method used. The new method (MPA) showed the best correlation to the CT scan (r = 0.997), even on short radiographs (10 cm distal the joint line). CONCLUSION: The measurement of the posterior tibial slope on a short lateral radiograph using the MPA is a reliable method and should be established as a standard. LEVEL OF EVIDENCE: Diagnostic study, Level II.

The del/del genotype of the nuclear factor-kappaB -94ATTG polymorphism and its relation to aggressive periodontitis.

BACKGROUND AND OBJECTIVE: Periodontitis is influenced by specific host-dependent immune responses. Periodontopathogens induce innate immune responses, amongst others, via toll-like receptor 2 (TLR2), resulting in activation of the nuclear transcription factor nuclear factor-kappaB (NF-kappaB). The aim of this case-control study was to evaluate links between genetic variants of these genes and chronic/aggressive periodontitis in a multivariate model. MATERIAL AND METHODS: A total of 141 patients with periodontitis (63 with chronic periodontitis and 78 with aggressive periodontitis) and 81 controls without periodontitis were included in the study. Polymorphisms in TLR2 (Arg677Trp, Arg753Gln) and in NF-kappaB (-94ins/delATTG) were determined by restriction fragment length polymorphism and fragment length analyses, respectively. Subgingival bacterial colonization was evaluated using a PCR/DNA probe test (micro-Ident). RESULTS: Although there was no association of the TLR2 polymorphism Arg753Gln with periodontitis, heterozygous carriers (Arg/Gln) were at a higher risk for colonization with bacteria of the 'red complex' (corrected p-value = 0.042). The del/del genotype of the NF-kappaB polymorphism was associated with aggressive periodontitis considering age, gender, smoking and approximal plaque index as potential confounders (odds ratio = 2.81, p = 0.035, 95% confidence interval: 1.08-7.33). del/del carriers had a higher risk for subgingival colonization with Aggregatibacter actinomycetemcomitans (odds ratio = 2.36, p = 0.030, 95% confidence interval: 1.09-5.1; adjusted for age, gender, smoking and pocket depth(bacteria)). CONCLUSIONS: The del/del genotype of NF-kappaB was shown to be associated with the occurrence of aggressive periodontitis.

Anti-NMDA receptor encephalitis: report of ten cases and comparison with viral encephalitis.

The California Encephalitis Project (CEP), established in 1998 to explore encephalitic etiologies, has identified patients with N-methyl-D-aspartate receptor (NMDAR) antibodies, the likely etiology of their encephalitis. This study compares the presentation of such patients to those with viral encephalitis, so that infectious disease clinicians may identify individuals with this treatable disorder. Patients were physician-referred, and standardized forms were used to gather demographic, clinical, and laboratory data. Features of anti-NMDAR+ patients were compared with the viral encephalitides of enteroviral (EV), rabies, and herpes simplex-1 (HSV-1) origins. Sixteen cases with confirmed viral etiologies were all negative on NMDAR antibody testing. Ten anti-NMDAR+ patients were profiled with a median age of 18.5 years (range 11-31 years). None were Caucasian. They had a characteristic progression with prominent psychiatric symptoms, autonomic instability, significant neurologic abnormalities, and seizures. Two had a teratoma, and, of the remaining eight, four had serologic evidence of acute Mycoplasma infection. The clinical and imaging features of anti-NMDAR+ patients served to differentiate this autoimmune disorder from HSV-1, EV, and rabies. Unlike classic paraneoplastic encephalitis, anti-NMDAR encephalitis affects younger patients and is often treatable. The association of NMDAR antibodies in patients with possible Mycoplasma pneumoniae infection warrants further study.

Impact of genetic variants of CD14 and TLR4 on subgingival periodontopathogens.

CD14 and toll-like receptor 4 (TLR4) are involved in host's immune response to bacterial pathogens including periodontal bacteria. Functional important gene polymorphisms are described for both genes. The aim of this study was to evaluate links between genetic polymorphisms of CD14 and TLR4 and risk markers of periodontitis in a multivariate model. One hundred and thirty-three periodontitis patients (chronic: n = 60, aggressive: n = 73) and 80 healthy controls without periodontitis were included in the study. Polymorphisms in CD14 c.-159C>T and in TLR4 Asp299Gly, Thr399Ile were determined by restriction fragment length polymorphism analyses. The clinical investigation included smoking status, plaque and bleeding indexes, pocket depth and attachment loss. Subgingival bacterial colonization was analysed molecularbiologically using the micro-Ident test. Prevotella intermedia occurred less frequently in individuals positive for the TT genotype of CD14 in bivariate analysis (odds ratio = 0.36%, confidence interval: 0.14-0.91, P = 0.045). In binary logistic regression analyses, the occurrence of this bacterium was significantly decreased in TT carriers (odds ratio = 0.31%, confidence interval: 0.81-0.12, P = 0.017) considering age, smoking and maximum clinical attachment loss at microbial test site as confounding factors. However, no significant association with chronic and or aggressive periodontitis and polymorphisms in CD14 and TLR4 could be proven. Although the CD14 c.-159C>T polymorphism could be shown to be associated with subgingival colonization with P. intermedia, there is no evidence that CD14 and TLR4 polymorphisms investigated are independent risk factors for chronic or aggressive periodontitis in German periodontitis patients.

Free bone cement fragments after minimally invasive unicompartmental knee arthroplasty: an underappreciated problem.

The minimally invasive implantation of unicompartmental knee arthroplasty (UKA) leads to excellent functional results, but due to the reduced intraoperative visibility the removal of excessive cement may be difficult. In a retrospective study we assessed radiologically the incidence of loose and excess bone cement in 120 UKAs and correlated it to the thickness of the tibial cement layer. In 25 cases loose or attached excess cement was seen. Two of these patients with loose cement bodies required revision surgery. An additional 2 patients not operated at our institution required revision because of pain and loss of motion. The average thickness of the tibial cement layer was 3.1 (1.7-5.0) mm in all the patients. But it was significantly higher in the group with excess cement bodies [3.3 (2.3-5.0) mm] compared to the group without excess cement [3.0 (1.7-4.1) mm] (P < 0.05). Symptomatic free cement bodies need to be removed immediately, if necessary arthroscopically, in order to avoid damage to the implants. To avoid this problem in minimally invasive UKA, intraoperative fluoroscopy, a dental mirror or a nerve hook seem to be useful tools to identify and remove loose or excess cement.

The interleukin-10 promoter haplotype ATA is a putative risk factor for aggressive periodontitis.

BACKGROUND AND OBJECTIVE: Interleukin-10 has been described as an anti-inflammatory cytokine and a B-cell proliferation factor. Promoter polymorphisms of the interleukin-10 gene have been associated with altered interleukin-10 expression. Therefore, the aim of this study was to evaluate three polymorphisms at positions -1082G>A, -819C>T and -590C>A in patients with generalized chronic periodontitis (n = 27) and generalized aggressive periodontitis (n = 32) in comparison with periodontitis-free controls (n = 34). MATERIAL AND METHODS: Interleukin-10 promoter polymorphisms were analyzed by polymerase chain reaction with sequence-specific primers (PCR-SSP). Distributions of single alleles, genotypes and haplotypes were calculated by the chi-square test. Risk factor analyses were carried out by logistic regression. Subgingival bacteria were subjected to molecular biological analyses using the micro-Ident test. RESULTS: The combination ATA/ATA was found only in patients with aggressive periodontitis (15.6 vs. 0.0%, p = 0.023). Taking into account age, gender, smoking and plaque level, an increased odds ratio (3.7, p = 0.04) for aggressive periodontitis was shown for subjects with the haplotype ATA. Prevotella intermedia was found to be decreased in ACC- positive (41.3 vs. 66.7%, p = 0.022), ATA-positive (33.3 vs. 57.1%, p = 0.032) and ACC/ATA-positive (20.0 vs. 55.9%, p = 0.002) individuals. In GCC/GCC-positive subjects, P. intermedia occurred more frequently (86.7 vs. 42.3%, p = 0.002). CONCLUSION: The haplotype ATA, which is known as a 'low interleukin-10 producer' is a putative risk indicator for generalized aggressive periodontitis.

Tuberculous meningoencephalitis in a pregnant woman presenting 7 years after removal of a cerebral granuloma.

We describe the unusual case of a young woman with a history of seizures and a granulomatous, likely tuberculous brain lesion that was surgically removed. She had an uneventful recovery without any additional therapy other than anti-epileptics. Seven years later, she presented during pregnancy with culture-confirmed tuberculous meningoencephalitis. This case highlights the spectrum of tuberculous central nervous system disease and the challenges in diagnosis.

Repercusión de un sistema de reconocimiento del habla integrado en un PACS/RIS con respecto al tiempo invertido en elaborar y poner a disposición los informes radiológicos / Impact of a PACS/RIS-integrated speech recognition system on the time expenditure in completing and making available radiology reports

Purpose: Quantification of the impact of a PACS/RIS-integrated speech recognition system (SRS) on the time expenditure for radiology reporting and on hospital-wide report availability (RA) in a university institution. Material and methods: In a prospective pilot study, the following parameters were assessed for 669 radiographic examinations (CR): 1. time requirement per report dictation (TED: dictation time (s)/number of images (examination) x number of words (report)) with either a combination of PACS/ tape-based dictation (TD: analog dictation device/ minicassette/transcription) or PACS/RIS/speech recognition system(RR: remote recognition/transcription and OR: online recognition/self-correction by radiologist), respectively, and 2. the ReportTur-naround Time (RTT) as the time interval from the entry of the first image into the PACS to the available RIS/HIS report. Two equal time periods were chosen retrospectively from the RIS database: 11/2002-2/2003 (only TD) and 11/2003-2/2004 (only RR or OR with speech recognition system (SRS)). The midterm (> 24 h, 24 h intervals) and short-term (< 24 h, 1 h intervals) RA after examination completion were calculated for all modalities and for CR, CT, MR and XA/DS separately. The relative increase in the mid-term RA (RIMRA: related to total number of examinations in each time period) and increase in the short-term RA (ISRA: ratio of available reports during the 1st to 24th hour) were calculated. Results: Prospectively there was a significant difference between TD/RR/OR (n = 151/257/261) regarding mean TED (0.44/0.54/0.62 s (per word and image)) and mean RTT.

Objetivo: Cuantificar la repercusión de un sistema de reconocimiento del habla integrado en un PACS/RIS en el tiempo invertido en los informes radiológicos y su disponibilidad en una Clínica Universitaria. Material y métodos: Estudio piloto prospectivo; en 669 radiografías se registró el tiempo invertido por dictado con cinta y sistemas PACS/RIS de reconocimiento (dictado por lotes o dictado en línea) y el Report Turnaround Time, intervalo de tiempo desde la introducción de imagen en PACS hasta tener informe disponible en RIS/CIS. En análisis retrospectivo de base de datos de RIS se estudió 11/2002-02/2003 y 11/2003-02/2004. Se calculó la media y el aumento relativo de la disponibilidad de informes a mediano y corto plazo tras la finalización del estudio. Resultados: Se observaron importantes diferencias en el tiempo invertido para cada modalidad (0,44/0,54/0,62 s por palabra e imagen) y del RTT medio (10,47/6,65/1,27 h). Se evaluaron retrospectivamente 37.898/39.680 informes de los períodos mencionados. En CR/TC, se observó un aumento medio del 20 por ciento en la disponibilidad de informes a corto plazo y en todas las modalidades fue más del triple en las primeras 24 h. En el caso de CR/TC/RM, el primer día hubo un aumento máximo de la disponibilidad a mediano plazo (factor 3,1/5,8/4,0) y en el caso de XA/DS, en el segundo día (factor 2,0). Conclusión: Cuando se utiliza un sistema de reconocimiento del habla se modifica el flujo de trabajo y se invierte inicialmente más tiempo para la elaboración de informes. Los sistemas de reconocimiento integrados en PACS/RIS mejoran considerablemente la disponibilidad de los informes a corto y mediano plazo, redundando en la calidad de la atención de los pacientes.

Quantitative 3D MR evaluation of autologous chondrocyte implantation in the knee: feasibility and initial results.

OBJECTIVE: To evaluate the feasibility of quantitative magnetic resonance imaging (MRI) based follow-up of cartilage volumetric data in patients after autologous chondrocyte implantation (ACI). To provide results from a 1-year follow-up study. METHODS: From 21 ACI patients sagittal FS 3D FLASH (50/11/30; 0.6x0.6x1.5mm(3)) MRI knee data sets were obtained pre and 1-year post-ACI surgery in the femoral condyles. After semi-automated segmentation and 3D reconstruction of the cartilage plates, cartilage volume, mean thickness and size of the cartilage-bone interface were calculated. Susceptibility artifacts were evaluated in all, intra-observer reproducibility was evaluated in six of the patients. Volumetric parameters were compared during follow-up and sensitivity to change was assessed for the total femur vs the separately evaluated medial/lateral portions of the femur. RESULTS: Reproducibility error (coefficient of variation %) was 3.9%/4.4% for the med./lat. tibial and 5.1% for the femoral cartilage volume. Susceptibility artifacts led to the exclusion of three out of the 21 patients, but were moderate in the remaining 18 patients, not preventing reproducible segmentation. In contrast to lack of significant change in the (non-operated) tibiae, a mean 6% increase of volume and thickness in the treated femora (P<0.001 Wilcoxon) relative to the pre-OP data was observed. Sensitivity to change for the femur ranged from 0.74 to 2.60 for cartilage volume and thickness and was improved when evaluating only the treated portion of the femur in contrast to the total femur. CONCLUSION: Our data indicate that despite postoperative susceptibility artifacts quantitative evaluation of cartilage volumetric parameters can be performed in ACI patients. The technique is able to describe changes of these parameters over 1 year. Volumetric follow-up may help to identify altered disease progression.

Beyond viruses: clinical profiles and etiologies associated with encephalitis.

BACKGROUND: Encephalitis is a complex syndrome, and its etiology is often not identified. The California Encephalitis Project was initiated in 1998 to identify the causes and further describe the clinical and epidemiologic characteristics of encephalitis. METHODS: A standardized report form was used to collect demographic and clinical data. Serum, cerebrospinal fluid, and respiratory specimens were obtained prospectively and were tested for the presence of herpesviruses, arboviruses, enteroviruses, measles, respiratory viruses, Chlamydia species, and Mycoplasma pneumoniae. The association between an identified infection and encephalitis was defined using predetermined, organism-specific criteria for confirmed, probable, or possible causes. RESULTS: From 1998 through 2005, a total of 1570 patients were enrolled. Given the large number of patients, subgroups of patients with similar clinical characteristics and laboratory findings were identified. Ten clinical profiles were described. A confirmed or probable etiologic agent was identified for 16% of cases of encephalitis: 69% of these agents were viral; 20%, bacterial; 7%, prion; 3%, parasitic; and 1%, fungal. An additional 13% of cases had a possible etiology identified. Many of the agents classified as possible causes are suspected but have not yet been definitively demonstrated to cause encephalitis; these agents include M. pneumoniae (n=96), influenza virus (n=22), adenovirus (n=14), Chlamydia species (n=10), and human metapneumovirus (n=4). A noninfectious etiology was identified for 8% of cases, and no etiology was found for 63% of cases. CONCLUSIONS: Although the etiology of encephalitis remains unknown in most cases, the recognition of discrete clinical profiles among patients with encephalitis should help focus our efforts toward understanding the etiology, pathogenesis, course, and management of this complex syndrome.