The authors studied the early morphologic changes of peripheral nerve, which is known as relatively radioresistant tissue to the X-ray irradiation, but recently clamied by several clinician through development of neuropathies after radiotherapy of the malignacy. Rabbits were received 1,000 or 2,000 cGy of X-ray on the knee joint areas. Sciatic nerves were extracted out 30 minutes, 1, 2, 4, 24 hours, and 3 and 7 days after irradiation. The morphologic changes were observed by light and electron microscopes. The results were summarized as follows: Light microscopically, only mild edema is noted. Electron microscopically, irregular separation and folding of myelin sheath with spherical body formation are noted. Above features were more prominent at later stages and aggregated nests of fragmented myelin were scattered 16 hours after irradiation. Schwann cell necrosis is noted after 24 hours. But above degenerative changes were scarcely present 7 days after irradiation. There is no remarkable axonal changes. The interstitial tissue revealed swelling and irregularity of surface of endothelial cells, and edema. On the basis of the results, it may be concluded that the peripheral nerve is injured by irradiation in early stages, and the main target of irradiation injury is thought to be myelin sheath and Schwann cells, which would be reversible and could be recovered promptly.
Rabbits ; Animals

No abstract available.
Reye Syndrome*

No abstract available.
Intervertebral Disc* ; Zygapophyseal Joint*

No abstract available.
Methylmethacrylate*

Symptomatic neuroepithelial cysts of the lateral ventricles are rare. The CT and MRI findings of the intraventricular neuroepithelial cysts in the surgically proven three cases are reported. On CT, the cysts had density similar to CSF, and the cyst walls were generally not seen. The cyst contents were slightly higher signal than CSF signal in Tl-weighted and proton density MR images. The delicate cyst walls were easily seen in spin echo MR images. MRI was better than CT in the demonstration of the cyst wall and the evaluation of the cyst content in patients with neuroepithelial cysts in the lateral ventricles.
Humans ; Lateral Ventricles* ; Magnetic Resonance Imaging ; Protons

Benign prostatic hyperplasia and urethral stricture are common causes of urethral obstruction over 50 years of age. To evaluate the usefulness of the Gianturco expandable stent for dilatation of the urethra, 14 single stents were placed in the posterior urethra (2 in prostatic urethra, 12 in membranous urethra), 20 in the anterior urethra. And 4 six-eight connected stents ere positioned in the posterior urethra to straddle at the internal sphincter or external sphincter and followed up for 2 weeks (one dog), 1 month (two dog), 2 months (one dog), 3 months (one dog), 5 months (one dog), 9 months (three dogs), and 14 months (two dogs). Seven of 18 stents in the posterior urethra and 5 to 20 in the anterior urethra were migrated during the follow-up. By 2 weeks after placement. 100% expansion was achieved in the posterior urethra, but by 1 month in the anterior urethra. Partial or complete epithelial covering of the stents was observed 1 month after stent placement in the anterior urethra, but mucosal folds were observed in the anterior and posterior urethra. Urinary incontinence was not observed in all cases. Our experience suggests that Gianturco expandable stent can be used in dilating and maintaining the lumen of the prostatic urethra and urethral stricture.
Animals ; Dilatation ; Dogs* ; Follow-Up Studies ; Prostatic Hyperplasia ; Stents* ; Urethra* ; Urethral Obstruction ; Urethral Stricture ; Urinary Incontinence

No abstract available.
Kyphosis* ; Spine* ; Tuberculosis*

Cephalometric superimposition is unable to evaluate tooth movement along the occlusal plane and the errors of photographing and superimposition of the occlusogram is also inevitable. The purpose of the present study was to evaluate the rotational movements of the maxillary posterior teeth following space closure after extraction of maxillary first premolars, using 3D dental images. In 19 adult females, analysis of rotational movements of the maxillary posterior teeth was performed between the initial and final 3D dental images superimposed on the maxillary hard palate. The results showed a diversity of rotational movements of posterior teeth. The causes of various rotational movements may be different rotation of molars in each case at the beginning of treatment, individual characters of the dental arch and tooth morphology. The results of the study indicate that accurate evaluation of rotational movements of posterior teeth following space closure after extraction of premolars using 3D dental images can be obtained through the subdivision of tooth movement during the initial aligning, space closure and finishing stages.
Adult ; Bicuspid* ; Dental Arch ; Dental Occlusion ; Female ; Humans ; Molar ; Palate, Hard ; Tooth Movement ; Tooth*

No abstract available.
Chondroma* ; Humans ; Young Adult*

No abstract available.
Fractures, Open*