Combined radiofrequency and kyphoplasty in painful osteolytic metastases to vertebral bodies

PURPOSE

The aim of this study was to assess retrospectively the safety and efficacy of combined radiofrequency (RF) and kyphoplasty (KP) in managing painful osteolytic metastases to vertebral bodies resistant to conservative treatments.

MATERIALS AND METHODS

Eleven patients (9 women and 2 men; mean age 68 years; age range 58-82) with painful osteolytic vertebral body metastases unresponsive to conservative treatments underwent RF combined with KP under general anaesthesia. Primary neoplasms were kidney carcinoma (n=1), breast carcinoma (n=1), thyroid carcinoma (n=2) and multiple myeloma (n=7). Lesion levels were cervical (n=1), thoracic (n=9) and lumbar (n=1). Combined RF and KP was well-tolerated by all patients. The procedures were performed using fluoroscopic guidance and intraoperative neurophysiology monitoring. Pain relief with the visual analogue scale (VAS) pain score and analgesic consumption were evaluated before and after treatment.

RESULTS

No complication occurred. In one case, we observed an asymptomatic cement leakage. Pain significantly decreased after treatment: the mean VAS pain score before treatment was 8 (range 7-10) vs. 1.8 (range 0-3) and 1.9 (range 1-3), respectively, 72 h and 6 weeks after the treatment. Analgesic reduction was achieved in all patients.

CONCLUSIONS

RF combined with KP represents a potential alternative method for palliation of painful spinal osteolytic metastases in selected patients. The procedures are safe and provide pain relief with bone augmentation and improvement in quality of life.

Amodal completion in texture visual evoked potentials

Amodal completion refers to the phenomenological finding of perceiving partly occluded objects as continuing uninterrupted behind an occluder. The outlying problem is how the visual system processes such non-local stimuli because the known processes of early vision are spatially restricted operations which segregate local differences in the visual image, and little is known about their interactions in producing the segmentation of the image into functionally coherent, or global, objects. We recorded human visual evoked potentials (VEPs) to texture stimuli and addressed local/non-local relationships in comparing a condition in which local edges were present, due to texture segregation, with a condition in which, in addition to local edges, textures appeared to continue as surfaces behind gray stripes due to non-local amodal completion. Subtraction of offset from onset responses showed: (1) a difference component due to texture segregation characterized by a negativity with onset at about 95 ms and lasting up to about 280 ms; (2) a further negativity, specifically elicited by amodal completion, with onset at about 142 ms, peaking at 175 ms, and lasting up to about 188 ms. Therefore, amodal completion occurs at an early processing stage of image analysis and the difference component in VEPs can be related to figure-ground perception.

Usefulness of trigeminal somatosensory evoked potentials to detect subclinical trigeminal impairment in multiple sclerosis patients

Trigeminal somatosensory evoked potentials (TSEPs) by surface electric pulse stimulation were recorded in 30 normal subjects and in 70 multiple sclerosis (MS) patients, 13 of whom presenting clinical trigeminal impairment. We observed significant prolongation of all TSEPs parameters in MS group. TSEPs were abnormal in 45 patients (64.3%). Clinical and neurophysiological data agreed in 36 patients (51%) on 84 sides (60%). TSEPs were able to detect clinically silent lesions 54 times. TSEPs recording proves to be an additional useful test in MS multimodal evoked potential protocols.