[Extraconal solitary fibrous tumor of the orbit]. / Extrakonaler solitärer fibröser Tumor der Orbita.

Solitary fibrous tumors (SFT) are rare spindle cell neoplasms derived from specialized fibroblasts. This tumor was first described in the pleura and later in the whole body including the orbit. Although an SFT is generally a benign tumor malignant transformation and metastasization have also been observed in a few cases. Complete excision is the therapy of choice. Here we report on a 50-year-old male patient whose orbital SFT was removed by transconjunctival anterior orbitotomy and 1.5 years after the operation the patient is recurrence and complaint-free.

Ependymoma of the cauda equina.

Myxopapillary ependymomas are benign tumours which occasionally metastasize along cerebrospinal fluid pathways. Extraneural metastases of spinal ependymomas, however, are very rare, even more so when situated in the pleura. We report the case of a 67 year old woman presenting with shortness of breath after recurrent myxopapillary ependymomas of the cauda equina. Chest X-ray showed multiple pleural lesions diagnosed as metastases of a myxopapillary ependymoma. The MIB-1 proliferation index was 3.1% for the initial spinal tumour, 14.2% for the first and 11.2% for the second recurrence while 12.0% for the pleural metastasis.

[Loss of strength and regeneration of knee extensor musculature after operations of the knee ligaments. EMG studies of the effect of the injury pattern, surgical procedure and after-care with special reference to electromyostimulation]. / Kraftverlust und -regeneration der Kniestreckmuskulatur nach Operationen am Kniebandapparat. EMG-Untersuchungen zum Einfluss von Verletzungsmuster, Operationsverfahren und Nachbehandlung unter besonderer Berücksichtigung der EMS.

Clinically relevant losses of the capacity of the extensor muscles of the thigh to contract voluntarily are usual after open knee joint operations and are known to lead frequently to a major delay in healing. In the present paper, a randomized prospective comparative study is presented in which the negative effect of the injury and surgical trauma on the extensor musculature of the thigh is compared between open and arthroscopically controlled cruciate ligament operations. The surface electromyogram is measured. The values found make it evident that an equally pronounced loss of strength amounting to more than 90% results after injuries in the region of the cruciate ligament apparatus and in open as well as arthroscopically controlled reconstruction operations. The alterations are mainly attributable to the surgical trauma. The injury on its own only leads to a roughly 25% loss of strength in the preoperative investigation. With an appropriate programme of follow-up treatment, the strength values are only partially restored after about six weeks. In the follow-up treatment, electromyostimulation has a significantly positive effect on the rectus femoris muscle, but not on the vastus lateralis muscle. According to our investigations, it is of preeminent importance to consider how to avoid the negative effect of the operation (with particular consideration of the arthroscopic procedure) on the function of the thigh musculature.

Evidence for subdivisions in the human suprachiasmatic nucleus.

The human suprachiasmatic nucleus was analysed by immunohistochemical demonstration of various substances in combination with 3-dimensional computerized reconstruction and video overlay facilities. In the human, the suprachiasmatic nucleus is not as compact as in the rodent. Its boundaries are not easily delineated using conventional stains, and it shows no obvious cytoarchitectonic structure. However, based on its chemoarchitecture, the human suprachiasmatic nucleus can be apportioned into five major subdivisions: Dorsal, comprising a crescent shaped mass of densely packed neurophysin/vasopressin-neurons as well as neurotensin-neurons, and also containing 3-fucosyl-N-acetyl-lactosamine (FAL)-positive neurons in its medial part. Central, occupying the core of the nucleus and consisting precisely of a region devoid of neurophysin/vasopressin neurons but demarcated by calbindin, synaptophysin, and a circumscribed cluster of vasoactive intestinal polypeptide-neurons and containing neurotensin neurons as well. Anteroventrally this division also contains some intermingled neurons positive for neurotensin, neuropeptide Y, somatostatin, and FAL. Ventral, extending from the anterior extreme of the preoptic recess caudolaterally to a field between the optic chiasm and the anteroventral margin of the supraoptic nucleus. This subdivision is specified by synaptophysin, calbindin, and substance P immunoreactivity and is almost free of glial fibrillary acidic protein. From its rostral portion, fibers immunoreactive for calbindin, vasoactive intestinal polypeptide, synaptophysin, and substance P protrude deeply into the optic chiasm. Medial, comprising a thin band between the subependymal zone and the dorsal subdivision, containing scattered somatostatin neurons. External, extending as a band around the dorsal and lateral borders of the nucleus, containing astrocytes expressing the FAL-epitope and scattered neurophysin/vasopressin and neurotensin neurons. These findings indicate that the human suprachiasmatic nucleus contains well-defined subdivisions with different, chemically specific, connections and provides a basis for comparing these subdivisions with the structure and function of subdivisions previously described for the suprachiasmatic nucleus in experimental animals. In addition, the findings strengthen the concept that the human suprachiasmatic nucleus generates and expresses circadian rhythms in a manner similar to that documented for the suprachiasmatic nucleus in experimental animals, and suggest that different subdivisions may subserve specific functional roles.