Renato Verdugo

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BACKGROUND Carpal tunnel syndrome results from entrapment of the median nerve in the wrist. Common symptoms are tingling, numbness, and pain in the hand that may radiate to the forearm or shoulder. Surgical treatment is widely preferred to non-surgical or conservative therapies for people who have overt symptoms, while mild cases are usually not treated. (More)
The sympathetic vasomotor innervation of the skin of the human hand was studied in 47 subjects who underwent local anaesthetic block of ulnar, median or radial nerves at elbow or wrist levels. Areas of cutaneous anaesthesia were compared with cutaneous territories of paralytic vasodilatation delineated by infrared telethermography. It was found that: (1)(More)
Patients with "reflex sympathetic dystrophy" or "causalgia" underwent sympathetic blocks. In protocol A (77 patients), we infused placebo (saline) for 30 minutes followed by phentolamine (35 mg). In protocol B (23 patients), the saline phase was followed by double-blind infusion of phentolamine or phenylephrine (500 micrograms), a second phase of saline,(More)
Abnormal movements may be a clinical feature in complex regional pain syndrome (CRPS), but their basic nature is unclear. Between August 1989 and September 1998, patients fulfilling diagnostic criteria for CRPS (I or II) and displaying abnormal movements were entered into a prospective study. Fifty-eight patients, 39 women and 19 men, met entry criteria; 47(More)
To test for the presence of "sympathetically maintained pain" (SMP), we administered placebo-controlled phentolamine sympathetic blocks to 14 patients with painful polyneuropathies. Six received i.v. infusion of saline for 30 minutes, followed by phentolamine (35 mg). In eight patients, the saline phase was followed by double-blind infusion of phentolamine(More)
Among 237 patients communicating chronic pain, associated with sensory-motor and "autonomic" displays, qualifying taxonomically for neuropathic pain, there were 16 shown through surveillance to be malingerers. When analyzed through neurological methods, their profile was characteristically atypical. There were no objective equivalents of peripheral or(More)
The quantitative somatosensory thermotest (QST) assesses the function of afferent channels concerned with sensory submodalities served by small calibre fibres. Measured ramps of ascending or descending temperature are applied to the skin through a Peltier contact thermode, and detection thresholds are recorded as the subject signals the onset of a(More)
Reflex sympathetic dystrophy (RSD) and causalgia appear to reflect identical pictures even though the latter is related to nerve injury and the former is not. Overriding past and present skepticism about a role for the sympathetic system in their cause and treatment, the International Association for the Study of Pain still recommends sympathetic blocks and(More)
The population of neurons and the neuronal size in the nucleus basalis of Meynert (nbM) were studied in 20 patients with definite Creutzfeldt-Jakob disease (CJD). When compared with a normal control group, the 20 CJD brains showed a significant loss of neurons and reduction of neuronal size, mainly in the middle level of the nbM and mostly affecting the(More)