NMR lineshapes were calculated for a model of lung, and NMR proton spectra were measured for individual voxels in an excised inflated rat lung. NMR lines for parenchymal lung regions containing alveoli, alveolar ducts, and capillaries were calculated using a computer simulation of the NMR signal from a three-dimensional honeycomb-like structure, a collection of modified Wigner-Seitz cells. These cells were modified by rounding the corners and increasing the thickness of the boundaries to model various degrees of lung inflation and lung water. NMR lineshapes were also calculated for the central or nonparenchymal lung regions containing bronchi and large blood vessels. A comparison of theoretical lineshapes with those measured in individual voxels both in the parenchymal and in the central (largely nonparenchymal) regions in excised rat lungs at an inflation pressure of 30 cm of water shows excellent agreement. These results indicate that the NMR lineshape reflects the underlying lung geometry. This research constitutes the first calculations and measurements of NMR lineshapes in lung. The appendix describes a new method for calculating the magnetic field inside a weakly diamagnetic material of arbitrary shape placed in an otherwise uniform external magnetic field. This new method does not require either solution of simultaneous equations or evaluation of integral expressions.

Gross discrepancy and error regarding the identification and location of the peroneal tubercle have been found in the literature. Furthermore, the authors found no evidence of a repeatable measurement technique in applicable descriptions of this osteologic landmark. In accordance with interrater reliability procedures, the authors established repeatability of peroneal tubercle measurements. In conjunction with the instrumentation's accuracy and resolution, the investigators infer reliability for these measurements. To the best of the authors' knowledge, this study is the only one in which interrater reliability was established for the morphometric assessment of the peroneal tubercle and the retrotrochlear eminence. The results also reestablish the correct anatomical presentation of the retrotrochlear eminence and the peroneal tubercle along the lateral surface of the calcaneus.

Normal radiographic anatomy of the first metatarsal bone is established through cadaver dissection, examination of bone specimens, and radiography. Extra-articular and distal articular anatomical landmarks are identified with wire markers. Dorsoplantar, lateral, lateral oblique, and medial oblique radiographs of 15 osteologic sites are presented, including the articular margins of the first metatarsal head, the borders of the three diaphyseal surfaces, the origins of the metatarsophalangeal collateral and metatarsosesamoid suspensory ligaments, and the insertions of the first cuneiform-metatarsal joint ligaments and the tibialis anterior and peroneus longus tendons. The correlation of gross anatomy and radiographs is described.

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A methodic analysis of foot radiographs is valuable when evaluating for joint disease. The author presents a system that allows the interpreter to establish a list of expected differential diagnoses. This is especially useful when the arthritide does not present with its classic radiographic appearance.