LaBan M M, Chamberlain C C, Jaiyesimi I, Shetty A N, Wang A M
Department of Physical Medicine and Rehabilitation, William Beaumont Hospital, Royal Oak, Michigan 48073, USA.
Am J Phys Med Rehabil. 1998 Nov-Dec;77(6):553-6. doi: 10.1097/00002060-199811000-00021.
Paraspinal muscle metastasis as initially suggested by an electromyographic pattern of isolated posterior primary ramus denervation and subsequently confirmed by magnetic resonance imaging has been reported. However, despite widespread systemic tumor dissemination, metastases to other skeletal muscle occurs infrequently. Uniquely, the paraspinal muscles are drained by the paravertebral plexus of veins. Valveless and at very low pressures, they communicate directly by collaterals with the portal system. Valsalva maneuvers with sudden increases of pressure within the intra-abdominal and intrathoracic cavities can force venous blood from the systemic circulation into the paravertebral plexus of veins. These same venous surges potentially carry tumor emboli to the vertebrae and/or from the vertebral medulla to the adjacent paravertebral muscle by the venous communicators. The inherent increased vascularity of metastatic tumor relative to the surrounding paraspinal muscle as demonstrated by magnetic venous angiography for the first time now permits earlier confirmation and biopsy of the electromyographic-suspected metastatic lesion. In this reported instance of a magnetic resonance imaging-recognized primary lung metastasis confirmed by magnetic resonance venography, there is the future promise of identifying earlier and smaller lesions by this technique.
据报道，最初由孤立性后初级分支去神经支配的肌电图模式提示，并随后经磁共振成像证实的椎旁肌转移情况已被发现。然而，尽管存在广泛的全身肿瘤播散，但转移至其他骨骼肌的情况却很少见。独特的是，椎旁肌由椎旁静脉丛引流。这些静脉丛无瓣膜且压力极低，它们通过侧支直接与门静脉系统相通。腹部和胸腔内压力突然增加的瓦尔萨尔瓦动作可迫使静脉血从体循环流入椎旁静脉丛。这些相同的静脉波动可能通过静脉交通支将肿瘤栓子输送至椎骨和/或从椎体髓质输送至相邻的椎旁肌。首次通过磁共振静脉造影显示，转移性肿瘤相对于周围椎旁肌的固有血管增多，现在可以更早地对肌电图怀疑的转移病灶进行确认和活检。在这个经磁共振静脉造影证实的磁共振成像识别的原发性肺转移的报道病例中，这项技术有望更早地识别出更小的病灶。
