Bony and cartilaginous anatomy of the patellofemoral joint

The patella as the largest sesamoid bone of the human body forms the patellofemoral joint with the patellar groove of the femur. The patellofemoral joint is a complex articulation with high functional and biomechanical requirements. Several anatomical variants of both patella and the trochlea exist. Multiple clinical problems of the knee may be caused by anatomical and physiological abnormalities of this joint. Exact knowledge about the anatomy, the biomechanics and the function of the patellofemoral joint is therefore required to understand its wide range of pathology.

Serotonin-Containing Cells in the Gastrointestinal Tract of Newborn Foals and Adult Horses

Serotonin (5-hydroxytryptamine, 5-HT), a regulatory amine of mucosal enterochromaffin cells plays an important role in the control of gastrointestinal smooth muscle contraction and epithelial secretion. Serotonin has also been associated with gastric ulcers, diarrhoea and abdominal pain. In spite of the high incidence of these gastrointestinal disorders in newborn foals and adult horses, no data are available regarding 5-HT immunoreactive cells (i.c.) in the gastrointestinal tract (GIT) of foals, and for adult horses, data are incomplete and contradictory. In this study, the distribution and relative frequency of 5-HT i.c. in the GIT of newborn foals and adult horses were determined immunohistochemically. In foals as in adults, a relatively large number of 5-HT i.c. were detected in all portions of the GIT. In foals, a significantly higher amount of cells was found in the pyloric region and margo plicatus of the stomach, as well as in the caecum and colon ascendens compared with adults. Our results provided rationale for further research concerning the role of 5-HT i.c. during the milk diet or in the regulation of gastrointestinal growth/cell proliferation, and in the pathogenesis of gastric ulcers, especially in newborn foals.

Multi-Detektor-CT zur Diagnostik angeborener Gefäßanomalien und ihrer Begleitbefunde bei Neugeborenen und Kleinkindern

PURPOSE

To assess the value of multidetector CT (MDCT) for evaluation of vascular anomalies (VA) and associated complications in newborns and infants.

MATERIALS AND METHODS

Seventy-five children (mean age: 9 +/- 6 months, range: 2 weeks to 24 months) with VA were examined using MDCT (4-, 8- or 16-row; collimation 0.5-1.25 mm; scan time 7-30 s), which was performed under controlled ventilation or free breathing. Image quality was rated using a 5-point scale. Image findings were correlated to echocardiography, conventional catheter angiography (CCA), bronchoscopy, and intraoperative findings.

RESULTS

High quality MDCT data were almost free of cardiac and respiratory motion. In all cases, VA morphology and topography in relation to adjacent structures, e. g. tracheal and esophageal compression caused by an aortic ring, could be assessed exactly and allowed the final diagnosis. Even aberrant vessels, such as aorto-pulmonary collaterals (MAPCA) with a diameter of less than 1 mm, could be identified and excellently visualized. Eighty percent (60/75) of all patients had benefited from the MDCT: in 31 patients CCA was neither necessary to perform surgical planning nor to exclude a VA; in an additional 29 patients radiation doses and sedation time due to interventional procedures could be reduced markedly.

CONCLUSIONS

MDCT can now be regarded as the modality of choice as a minimally invasive, robust, and accurate technique for the diagnosis of complex VA, their potentially life-threatening complications and preoperative planning even in newborns and infants. Its accuracy for detecting VA appears equivalent to CCA while it is more accurate in delineating potential life-threatening complications.

Vordere Kreuzbandplastik mit proximaler Endobutton-Fixation eines Lig.-patellae-Transplantats

BACKGROUND

Interference screw fixation in ACL reconstruction with bone-patellar tendon-bone graft (BPTB) is a potential source of intraoperative complications such as graft laceration. Further problems are artifacts on MRI and screw removal in revision surgery. These problems can be avoided by using distant fixation with the EndoButton. We designed this study to evaluate the clinical as well as the subjective outcome of ACL reconstruction with BPTB graft and femoral fixation with the EndoButton.

METHODS

A total of 51 patients (7 female, 44 male) were examined 2-5 years after ACL reconstruction with BPTB graft and femoral fixation with the EndoButton. We used the IKDC form, Lysholm score, Tegner activity score, and digital radiographs (AP, lateral, axial) for the evaluation.

RESULTS

Of all the patients included in the study, 87% showed a "normal" or "nearly normal" knee function according to the IKDC score, Lysholm score 94.2+/-7.9, Tegner score 6.4+/-1.2, and subjective IKDC 89.9+/-11.9. Radiological signs of arthritic changes could be seen in ten cases.

CONCLUSION

The clinical outcome of ACL reconstruction with EndoButton fixation is comparable to other studies on ACL reconstruction with interference screw fixation. However, since the EndoButton avoids potential problems of the interference screw fixation, we recommend this fixation technique for ACL reconstruction with BPTB graft.

Quantitative analysis of lung and tumour mobility: comparison of two time-resolved MRI sequences

The purpose of this study was to describe the use of parallel imaging technique (PAT) using dynamic MRI in lung and tumour mobility during the breathing cycle. 20 patients with stage I non-small cell lung carcinoma were investigated using two dynamic gradient echo sequences with PAT (TrueFISP (fast imaging with steady precession), and fast low angle shot (FLASH). Craniocaudal distance from the apex to the diaphragm of the thorax and tumour mobility during the breathing cycle were measured. Signal-to-noise ratio (SNR) of the tumour was determined. In spite of the different temporal resolutions both trueFISP and FLASH sequence proved to be adequate to continuously measure lung motion and tumour mobility. SNR of the tumour was significantly higher using the trueFISP sequence than FLASH sequence (20.7+/-3.6 vs 5.8+/-2.3, p<0.01). Mobility of the tumour bearing hemithorax was significantly lower compared with the non-tumour bearing hemithorax (p<0.05). Dynamic MRI using PAT allows for continuous quantitative documentation of tumour mobility and lung motion. Because of the higher SNR, trueFISP sequence provides a better delineation of intrapulmonary lesions with a sufficient temporal resolution.

Time-resolved echo-shared parallel MRA of the lung: observer preference study of image quality in comparison with non-echo-shared sequences

The aim of this study was to evaluate the image quality of time-resolved echo-shared parallel MRA of the lung. The pulmonary vasculature of nine patients (seven females, two males; median age: 44 years) with pulmonary disease was examined using a time-resolved MRA sequence combining echo sharing with parallel imaging (time-resolved echo-shared angiography technique, or TREAT). The sharpness of the vessel borders, conspicuousness of peripheral lung vessels, artifact level, and overall image quality of TREAT was assessed independently by four readers in a side-by-side comparison with non-echo-shared time-resolved parallel MRA data (pMRA) previously acquired in the same patients. Furthermore, the SNR of pulmonary arteries (PA) and veins (PV) achieved with both pulse sequences was compared. The mean voxel size of TREAT MRA was decreased by 24% compared with the non-echo-shared MRA. Regarding the sharpness of the vessel borders, conspicuousness of peripheral lung vessels, and overall image quality the TREAT sequence was rated superior in 75-76% of all cases. If the TREAT images were preferred over the pMRA images, the advantage was rated as major in 61-71% of all cases. The level of artifacts was not increased with the TREAT sequence. The mean interobserver agreement for all categories ranged between fair (artifact level) and good (overall image quality). The maximum SNR of TREAT did not differ from non-echo-shared parallel MRA (PA: TREAT: 273+/-45; pMRA: 280+/-71; PV: TREAT: 273+/-33; pMRA: 258+/-62). TREAT achieves a higher spatial resolution than non-echo-shared parallel MRA which is also perceived as an improved image quality.