Cryosurgery of Periocular Moderately Aggressive Basal Cell Carcinoma.

Uncertainty exists regarding the results of treating basal cell carcinomas with a more aggressive growth pattern than nodular growth with cryosurgery. Over the years, some medium aggressive, well-defined basal cell carcinomas have been treated with cryosurgery at the combined ophthalmology-dermatology recipiency at Sahlgrenska University Hospital, Gothenburg in Sweden. The medical records of these patients were reviewed to analyse the results. A total of 53 cryosurgeries were performed in 52 patients during 2009 to 2016. None of these patients had a recurrence within the first 3 years. There were 2 recurrent tumours after 5 years and 1 after 9 years. It is concluded that cryosurgery is an effective treatment option for well-defined basal cell carcinomas with an intermediate growth pattern.

Experimental Disc Herniation in the Rat Causes Downregulation of Serotonin Receptor 2c in a TNF-dependent Manner.

BACKGROUND: During recent decades, the knowledge of the pathophysiology of disc herniation and sciatica has drastically improved. What previously was considered a strict biomechanical process is now considered a more complex interaction between leaked nucleus pulposus and the tissue in the spinal canal. An inflammatory reaction, with tumor necrosis factor (TNF) playing an essential role, has been demonstrated. However, the exact mechanisms of the pathophysiology of disc herniation remain unknown. QUESTIONS/PURPOSES: In this study we use an animal model to investigate (1) if and/or how experimental disc herniation affects gene expression in the early phase (24 hours postsurgery) in the dorsal root ganglion; and (2) if TNF inhibition can reduce any observed changes. METHODS: A rat model of disc herniation was used. Twenty rats were evenly divided into four groups: naïve, sham, disc herniation, and disc herniation with TNF inhibition. The dorsal root ganglion of the affected nerve root was harvested 24 hours after surgery and analyzed with a TaqMan Low Density Array(®) quantitative polymerase chain reaction assay. Gene expression levels in sham were compared with disc herniation to assess question 1 and disc herniation to disc herniation with TNF inhibition to assess question 2. RESULTS: Experimental disc herniation caused a decrease in the expression of the serotonin receptor 2c gene (p = 0.022). TNF inhibition was found to reduce the observed decrease in expression of serotonin receptor 2c (p = 0.037). CONCLUSIONS: Our results suggest that a decrease in the expression of the serotonin receptor 2c gene may contribute to the pathophysiology of disc herniation. Further research on its involvement is warranted. CLINICAL RELEVANCE: This pilot study gives a brief insight into cellular changes that may contribute to the pathophysiology of disc herniation. This knowledge may contribute to the development of more and better treatment options for patients with disc herniation and sciatica.

New, clinically more relevant model for nerve root injury in the rat.

STUDY DESIGN: Exposure to nucleus pulposus and displacement of intraspinal nervous structures with assessment of spontaneous behavioral changes in rats. OBJECTIVE: To develop a controlled, experimental model for nerve root injury. SUMMARY OF BACKGROUND DATA: There are a number of experimental models presented for studies on radiculopathies. One frequently used model is based on exposure to nucleus pulposus and displacement of the dorsal root ganglion (DRG). However, it is clinically more common that the nerve roots are displaced/compressed than the DRG. In this study, we developed a model for displacement of the nerve root by modifying the DRG model. METHODS: After removing the left L3-L4 facet joint, the underlying disc was punctured, and the L4 nerve root was displaced laterally by an injection needle (n = 10). In sham experiments, the same procedure was performed without disc puncture and displacement (n = 10). In 10 rats, the left L4-L5 facet joint was removed. The underlying disc was punctured and the L4 DRG was displaced medially by an injection needle. Assessment of spontaneous behavioral changes was performed on days 1, 3, 7, 14, and 21, postsurgery. RESULTS: There was a clear increase in duration of the behavior "unloading of the paw" after displacement of the DRG that was most pronounced on day 1 and then gradually declined. There was a similar pattern for this behavior induced by nerve root displacement, although the duration was higher than that for the DRG displacement. No apparent trends in behavioral changes were observed for the other behaviors studied. CONCLUSION: Displacement of the nerve root induced more changes in the pain behavior than displacement of the DRG, but only for the behavior unloading of the paw. Because nerve root injury is more common than DRG injury, this model may be more clinically relevant than the DRG model. LEVEL OF EVIDENCE: N/A.