We report the features of non-length dependent small fiber neuropathy (SFN) and compare them to those with distal length-dependent SFN. In a series of 224 consecutive neuropathy patients, we evaluated 44 patients with SFN diagnosed in the presence of both symptoms and signs. Eleven were classified as non-length dependent SFN. Disease associations were Sjögren's syndrome (two patients), impaired glucose tolerance, rheumatoid arthritis, hepatitis C virus, Crohn's disease, and idiopathic (five patients). In the 33 patients with distal SFN, the age of onset was significantly older and more had impaired glucose metabolism (16/33). In both groups, pain was mainly characterized as burning, but patients with non-length dependent SFN more often reported an "itchy" quality and allodynia to light touch.
of a levodopa-nonresponsive PD patient who failed to improve after pallidotomy also failed to improve after DBS STN. 10 Our patients were all levodopa-responsive and, aside from a single patient, improved after their pallidotomy.There are several reasons why postpallidotomy STN DBS may result in less robust motor improvement. First, there is an obvious referral bias toward patients who were not satisfied after their pallidotomy, either for objective or subjective reasons. This may represent a more aggressive disease process or more atypical course. The pre-and postpallidotomy off drug UPDRS scores, however, were similar in this group of pallidotomy DBS patients compared to our pallidotomy population in general (n ϭ 89). 1 Dyskinesia scores were also similar. Second, electrophysiological recordings, on which we greatly rely for placement, can be altered in the STN following GPi ablation, possibly resulting in suboptimal placement. 11 Random suboptimal placement is possible in either group. Third, there could be redundant physiological effects that would mitigate against subsequent improvement after the second procedure. A single study that simultaneously implanted GPi and STN DBS found that combined stimulation was no more effective than STN stimulation alone. 12 Fourth, we present a relatively small number of patients and the results could be different with a larger sample.Overall, the small corpus of literature on the efficacy and safety of postpallidotomy STN DBS is mixed. We recommend prudence when considering DBS in this population.
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In a series of 44 consecutive patients with Charcot-Marie-Tooth disease (CMT), we found restless legs syndrome (RLS) in 10 of 27 CMT type 2 (CMT2) patients (37%) and in none of 17 CMT type 1 patients (p = 0.004). In the CMT2 patients, RLS was associated with positive sensory symptoms (10/10 versus 10/17; p = 0.026). This finding supports the view that a disorder of sensory input plays a role in the pathogenesis of RLS. Symptomatic treatment may benefit these patients.
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