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Background : Osteoarthritis is a chronic disorder that affects the synovial joints by the progressive loss of articular cartilage. In the hip, the largest weight-bearing joint, the deterioration of articular cartilage and acetabular labrum can cause pain, diminishing the quality of life for patients. This study presents changes in reported pain scales from patients who received Wharton's jelly applications to cartilage deterioration in the hip from the observational retrospective repository at Regenative Labs. Methods : Sixty-nine patients were selected based on inclusion criteria with patient-reported pain scales, including the Numeric Pain Rating Scale and the Western Ontario and McMaster University Osteoarthritis Index, collected at the initial application, 30, and 90-day follow-up visits. Thirteen patients received a second allograft application and had additional follow-up visits at 120 and 180 days. Results : Five of the six scales used showed a statistically significant improvement in average scores across the cohort. The greatest improvements were observed in the NPRS with a 31.36% improvement after 90 days and a 44.64% improvement for patients with two applications after 180 days. The minimal clinically important difference (MCID) was also calculated to determine the perceived value of care for each patient with 44.9% of patients exceeding the MCID and 78.3% reporting at least one level of improvement. Conclusions : The positive outcomes for the patients in this cohort suggest WJ to be a promising alternative care option for patients with structural tissue degeneration in the hip refractory to the current standard of care.

With the increasing occurrence of rotator cuff injuries every year, there is a great need for a reliable treatment option. Wharton's Jelly contains several components that can positively impact the replacement and repair of musculoskeletal defects. The overall objective of this study is to evaluate the improvement of patient-reported pain scales after applying Wharton's Jelly (WJ) in rotator cuff defects. Eighty-seven patients with rotator cuff defects who failed at least eight weeks of conservative treatment were selected from the retrospective repository. A total of 2 cc of WJ flowable allograft was applied to the specific affected anatomy, the most common being supraspinatus tendon, biceps tendon insertion, labral tear, and subscapularis tear. No adverse reactions were reported. Statistically significant improvements were found from the initial to Day 90 in all scales. Patient satisfaction was calculated using minimal clinically important differences. No statistically significant differences were found in mean changes between gender, BMI, and age. Scanning electron microscopy images reveal the similarities between the collagen matrix in WJ and the rotator cuff. The significant improvement in patient outcomes coincides with the current literature analyzing WJ applications with other structural defects around the body. WJ is a promising alternative for musculoskeletal defects when the standard of care fails.

In order to discuss first experiences with the implementation of the EU Regulation on In Vitro Diagnostic Medical Devices (IVDR) about one year after its entry into force, the German Association of the Scientific Medical Societies (AWMF e.V.) organized a full-day public webinar. Overall, it became clear that the implementation of the IVDR still poses significant challenges for laboratory medicine and pathology. Corrections at the political level and implementation with a sense of proportion are required. Before the long-term goal of the IVDR, i.e. the increase in patient safety, can be realized, the prevention of disadvantages for patients due to gaps in care must be strived for in the medium term by all parties involved., (Copyright © 2024 Vogeser et al.)

Purpose: To compare the performance of single shot echo planar imaging (SSEPI) with three-dimensional-multishot echo-planar imaging (EPI) based on principles-of-echo-shifting-with-a-train-of-observations (PRESTO) in combination with a standard quadrature head coil and, as an alternative, a multiple receiver coil in intraoperative functional magnetic resonance imaging (fMRI)., Materials and Methods: Six healthy subjects underwent fMRI with visual stimulation using a SSEPI and a PRESTO-sequence with both coil systems. Statistical evaluation was done with a scanner-based post-processing software and SPM 99. The number of activated voxels in the visual cortex, the percent signal change between rest and activation, and finally the signal-to-noise ratio (SNR) during time course were measured and compared for both coil systems and both sequences, used in four different combinations., Results: Blood oxygen level dependent (BOLD) signal changes were the lowest with PRESTO and standard head coil and the highest for SSEPI and phased array coil. For the latter combination, a significantly higher signal change and larger activation size was observed together with a better SNR. SSEPI yielded similar performance using both coils., Conclusion: SSEPI was superior due to its better SNR and a higher BOLD signal change in the defined settings, irrespective of the coil used. In a stereotactical setup the phased array coil can be used to generate fMRI data without loss of image quality., (Copyright 2004 Wiley-Liss, Inc.)

For application in magnetic resonance (MR) guided stereotactic neurosurgery, two methods for transformation of MR-image coordinates in stereotactic, frame-based coordinates exist: the direct stereotactic fiducial-based transformation method and the indirect anatomical landmark method. In contrast to direct stereotactic MR transformation, indirect transformation is based on anatomical landmark coregistration of stereotactic computerized tomography and non-stereotactic MR images. In a patient study, both transformation methods have been investigated with visual inspection and mutual information analysis. Comparison was done for our standard imaging protocol, including t2-weighted spin-echo as well as contrast enhanced t1-weighted gradient-echo imaging. For t2-weighted spin-echo imaging, both methods showed almost similar and satisfying performance with a small, but significant advantage for fiducial-based transformation. In contrast, for t1-weighted gradient-echo imaging with more geometric distortions due to field inhomogenities and gradient nonlinearity than t2-weighted spin-echo imaging, mainly caused by a reduced bandwidth per pixel, anatomical landmark transformation delivered markedly better results. Here, fiducial-based transformation yielded results which are intolerable for stereotactic neurosurgery. Mean Euclidian distances between both transformation methods were 0.96 mm for t2-weighted spin-echo and 1.67 mm for t1-weighted gradient-echo imaging. Maximum deviations were 1.72 mm and 3.06 mm, respectively.

This article deals with technical aspects of intraoperative functional magnetic resonance imaging (fMRI) for monitoring the effect of deep brain stimulation (DBS) in a patient with Parkinson's disease. Under motor activation, therapeutic high-frequency stimulation of the subthalamic nucleus was accompanied by an activation decrease in the contralateral primary sensorimotor cortex and the ipsilateral cerebellum. Furthermore, an activation increase in the contralateral basal ganglia and insula region were detected. These findings demonstrate that fMRI constitutes a promising clinical application for investigating brain activity changes induced by DBS.

A new approach is presented for unwarping geometrical distortions in echo planar imaging (EPI)-based statistical parametrical maps (SPM). With the developed method, a substantial reduction of geometrical distortions in the order of 5-15 mm down to a residue of approximately 1-2 mm was possible, thus allowing reliable activation localization and, hence, interpretation after fusion with undistorted conventional anatomic images. The unwarping procedure is an optimized combination of two distortion correction methods, the "inhomogeneity mapping" and the coregistration approach. Local and global distortions, the first one object-dependent, the second one caused by imperfect gradient waveforms, are reduced. With several examples of patients and volunteers, the applicability for stereotactic neurosurgery is demonstrated.

Objective: The purpose of the study was to examine the possibilities for reducing radiation exposure in uroradiology using digital flat-panel silicon X-ray detector radiography. We compared the subjectively determined image quality of abdominal radiographs and urograms obtained on a digital flat-panel detector radiography system with those obtained on a computed radiography system. SUBJECTS AND METHODS. Fifty patients who had a clinical indication for urography underwent unenhanced abdominal imaging that was alternately performed using flat-panel silicon X-ray detector radiography or computed radiography. For patients who required a second radiograph with contrast medium, the examination modality was changed to avoid exposing the patients to excess radiation. The images obtained on flat-panel X-ray detector radiography were obtained at half the radiation dose of the images obtained on computed radiography (800 speed vs 400 speed). The resulting 50 pairs of images were interpreted by four independent observers who rated the detectability of structures of bone and the efferent urinary tract relevant to diagnosis and compared the image quality., Results: At half the radiation dose, digital flat-panel X-ray detector radiography provided equivalent image quality of the liver and spleen, lumbar vertebrae 2 and 5, pelvis, and psoas margin on abdominal radiographs. The image quality obtained with digital flat-panel X-ray detector radiography of the kidneys, the hollow cavities of the upper efferent urinary tract, and the urinary bladder was judged to be statistically better than those obtained with computed radiography., Conclusion: With half the exposure dose of computed radiography, the flat-panel X-ray detector produced urograms with an image quality equivalent to or better than computed radiography.

Purpose: To determine relaxation times of metabolite signals in proton magnetic resonance (MR) spectra of immature brain, which allow a correction of relaxation that is necessary for a quantitative evaluation of spectra acquired with long TE. Proton MR spectra acquired with long TE allow a better definition of metabolites as N-acetyl aspartate (NAA) and lactate especially in children., Materials and Methods: Relaxation times were determined in the basal ganglia of 84 prematurely born infants at a postconceptional age of 37.8 +/- 2.2 (mean +/- SD) weeks. Metabolite resonances were investigated using the double-spin-echo volume selection method (PRESS) at 1.5 T. T1 was determined from intensity ratios of signals obtained with TRs of 1884 and 6000 msec, measured at 3 TEs (25 msec, 136 msec, 272 msec). T2 was determined from signal intensity ratios obtained with TEs of 136 msec and 272 msec, measured at 2 TR. Taking only long TEs reduced baseline distortions by macromolecules and lipids. For myo-inositol (MI), an apparent T2 for short TE was determined from the ratio of signals obtained with TE = 25 msec and 136 msec. Intensities were determined by fitting a Lorentzian to the resonance, and by integration., Results: Relaxation times were as follows: trimethylamine-containing compounds (Cho): T1 = 1217 msec/T2 = 273 msec; total creatine (Cr) at 3.9 ppm: 1010 msec/111 msec; Cr at 3.0 ppm: 1388 msec/224 msec; NAA: 1171 msec/499 msec; Lac: 1820 msec/1022 msec; MI: 1336 msec/173 msec; apparent T2 at short TE: 68 msec., Conclusion: T1 and T2 in the basal ganglia of premature infants do not differ much from previously published data from basal ganglia of older children and adults. T2 of Cho was lower than previous values. T2 of Cr at 3.9 ppm and Lac have been measured under different conditions before, and present values differ from these data., (Copyright 2003 Wiley-Liss, Inc.)

Purpose: To determine the success rate of percutaneous ultrasonographically (US) guided thrombin injection in the treatment of femoral pseudoaneurysms and to evaluate the effects of thrombin injection on systemic coagulation parameters., Materials and Methods: Fifty femoral pseudoaneurysms (37 simple pseudoaneurysms with one lobe and 13 complex pseudoaneurysms with two or three lobes) were treated with US-guided percutaneous thrombin injections. Pseudoaneurysm size, neck length and width, thrombin dose, outcome of therapy, and complications were documented prospectively. Duplex sonographic follow-up examinations were performed at 12-24 hours and 5-7 and 21-25 days. In 25 patients, activated thromboplastin time, Quick test (prothrombin time), thrombin time, fibrinogen, D-dimer, antithrombin III, thrombin-antithrombin III complex, and prothrombin fragments 1 and 2 were determined before and at 2, 5, and 10 minutes after thrombin injection. Differences in results before and those after thrombin injection were evaluated by means of the one-sample t test., Results: Mean volume of pseudoaneurysms was 5.84 cm(3) +/- 4.89 (SD). Fifty-eight thrombin injections were performed. Mean thrombin dose was 357 IU +/- 291 in simple and 638 IU +/- 549 in complex pseudoaneurysms. Primary success rate was 36 of 37 (97%) for simple and eight of 13 (61%) for complex pseudoaneurysms. Reperfusion occurred in four complex pseudoaneurysms (none in simple ones). Secondary success rate was 100%. No thromboembolic, infectious, or allergic complications occurred. During follow-up, reperfusion was detected in one patient with a complex pseudoaneurysm. Levels of thrombin-antithrombin III complex increased significantly (P <.05) after thrombin injection, whereas changes in all other laboratory tests were not significant., Conclusion: US-guided percutaneous injection of thrombin is successful and safe in the management of femoral pseudoaneurysms. The increase of thrombin-antithrombin III complex indicates the possibility of thrombin passage into the arterial circulation.

Objectives: To evaluate the performance and efficacy of endovascular irradiation after percutaneous transluminal angioplasty (PTA) of de-novo femoropopliteal stenoses in a pilot study., Methods: 6 patients received non-centered endovascular irradiation (12 Gray at surface of the vessel wall) immediately after angioplasty of de-novo femoropopliteal stenosis, 1 patient was given centered endovascular irradiation using 192-iridium (12 Gray at surface of the vessel wall) Centered irradiation was considered for two other patients. Duplex sonographies and interviews were performed the day before and after PTA and after 1, 3, 6, 9, 12, 18, 24 months up to 4 years. Intraarterial angiography was performed in symptomatic patients., Results: Non-centered endovascular irradiation was possible in all patients without problems or complications. Centered irradiation was not possible in two patients with the cross-over approach. One thromboembolic complication occurred during centered irradiation. Both restenosis and new stenosis at the edge of irradiated distance occurred in 1/7 patients. No other side effects were observed during follow-up., Conclusions: In our pilot study endovascular irradiation after angioplasty of de-novo femoropopliteal stenosis was possible with low rates of complications and restenosis and taking vessel anatomy into account.

The purpose of this study is to visualize brainstem auditory pathways by functional magnetic resonance imaging (fMRI). Eighteen healthy volunteers (age 28 to 42 years) with normal hearing function underwent fMRI examination on a 1.5 Tesla imaging system (Philips, Best, The Netherlands) with periodic click stimulation. Blood oxygen level dependent images were obtained using a three-dimensional EPI sequence with shifted echo technique (principles of echo shifting with a train of observations). Control scans without click stimulation were obtained in the identical setting. Cross correlation activation maps were calculated using a postprocessing tool (Philips). They were matched with anatomic slices of identical orientation and thickness. Five of 18 subjects were excluded because of motion artifacts. In 4/13 significant activation was observed at the root entry zone of the ipsilateral acoustic nerve corresponding to the cochlear nuclei. In 11/13 subjects, significant activation was found in the same slice contralaterally close to the floor of the 4th ventricle, corresponding to the expected region of the superior olivary nucleus. Activation of the rostral parts of the auditory pathway (inferior colliculus, medial geniculate body) was not found. In the absence of the stimulus no activation occurred in these structures. It was concluded that activation of the brainstem auditory pathways by click stimuli can be visualized by fMRI.

Purpose: To estimate the accuracy of the determination of tip position of MR compatible biopsy needles based on signal voids and artifacts in MR guided biopsies., Method: In a nylon grid phantom an MR compatible 18G needle (E-Z-EM) was measured in a 1.0 T imager using TSE- and FFE-sequences of 20 s and 40 s duration in 34 different orientations of needle versus B0, frequency and slice selection gradient. 4 radiologists with no experience in the evaluation of signal void artifacts estimated the needle tip positions from needle tip artifacts. The readers determined the needle tip before and after a 15 minute training session based on high resolution images with explanation of size and shape of specific artifacts of biopsy needles in 12 different orthogonal or parallel orientations to B0 and frequency encoding gradient that are possible if the needle lies parallel to the slice, i.e. orthogonal to the slice selection gradient. The values obtained before and after the training session were compared to the real position of the needle tip., Results: Mean distance of actual needle tip and tip position as determined from images was 1.8 +/- 2.3 mm in TSE-versus 2.5 +/- 1.2 mm in FFE-images, with the needle length overestimated. After a 15 minute training session the positioning error decreased significantly to 0.2 +/- 1.8 mm for TSE-sequences and to 1.0 +/- 1.8 mm for FFE-sequences. A higher accuracy of tip localization was obtained with TSE sequences., Conclusion: In MR guided biopsies using FFE- and TSE-sequences the needle position can be more accurately determined if the reader is familiar with the 12 orthogonal or parallel positions of the needle with respect to B0 and frequency encoding gradient and the corresponding artifacts.

Purpose: Who refers patients for a color duplex ultrasonography (CDUS) in the routine work of a radiological university department and how frequent are repeat examinations?, Material and Methods: 1110 patients had at least one CDUS examination between 5/97 and 5/98. The specialities of the referring physicians/primary examiners and the inpatient or outpatient status of the patients were documented at the first consultation. Additionally the patients were asked by the medical staff, whether, how often, and by whom ultrasonographic, CT, or MR examinations of the same organ system had been carried out during the last 4 weeks without evidence of any clinical changes., Results: 97% of the 1118 patients were referred by one of the university departments. The arterial system was exclusively investigated in 58% and the venous system in 29% of the cases. 81% of the 651 arterial examinations were requested by the Departments of Vascular/Cardiac Surgery and Radiology. 75 repeated ultrasonographic examinations were documented in 67 (6%) of the 1118 consultations. Repetitions were documented in 8% of the arterial and in 3% of the venous examinations. X-ray angiographies were already done or planned in 105 of the 625 arterial CDUS (16%). Ultrasonographic referrals with parallel phlebographies (1% of 320 venous indications) as well as parallel CT and MR examinations (1% of the 1118 consultations, respectively) were the exception., Conclusions: In the described setting, CDUS was mainly used to assess the arterial vascular system prior to vascular surgery and radiological interventions. Repeat ultrasonographies alone (6%) and parallel examinations altogether (14%) were observed less frequently than expected.

Purpose: What is the percentage of repeat examinations in the ultrasonographic section of a radiological university department?, Methods: All 4116 patients, who were first examined in the sonographic section of the Radiologic Department of the University of Cologne from 5/97 to 5/98, were asked by the medical staff, whether, how often and by whom ultrasonographic, CT or MR examinations of the same organ system had been carried out during the last 4 weeks without evidence of clinical changes. The data were documented using a structured questionnaire., Results: Sonographic repeated examinations documented in 443 (10.8%) of the 4116 consultations. The proportion of in- to outpatients with repeat examinations was 26.0% to 74.0%. Contrarily, the repeated ultrasonographies were done by practitioners in 62.3% and by the university staff in 33.2% (radiology 48.2%). With regard to the 4116 consultations, the abdomen (81.1%) was the organ system most often examined repeatedly. Computed tomographies were already done or planned in 305 of 4116 patients (7.4%) and MR-tomographies were already done or planned in 57 patients (1.4%)., Conclusion: The rate of repeated ultrasonographic examinations in a radiological university hospital was 19.6%.