Search Results

You are looking at 11 - 20 of 81 items for

  • Author or Editor: Kim J. Burchiel x
Clear All Modify Search
Restricted access

Terrence L. Pencek and Kim J. Burchiel

✓ Although it is well documented that retained foreign bodies are associated with delayed intracranial abscess, there are few reports of anaerobic organism growth. A case is presented in which a left parieto-occipital abscess surrounded a metallic fragment implanted when a mortar shell exploded in Vietnam 15 years before. The diagnostic evaluation and surgical management of this case are presented.

Restricted access

Kim J. Burchiel and Lisa C. Russell

✓ The effect of topical glycerol application on normal and previously injured saphenous nerves was tested in 20 Sprague-Dawley rats. Anhydrous glycerol treatment of five normal nerves showed a rapid loss of C-fiber conduction within 5 minutes of application, while after 10 to 30 minutes, a complete conduction blockade in all fiber types was produced. The effect of anhydrous glycerol on both spontaneous firing from the neuroma and impulse propagation within the nerve was examined in 11 rats that had undergone saphenous neurotomy 7 days previously. In these animals, cessation of spontaneous action potential production from the neuroma was the earliest electrophysiological change noted, followed by loss first of C-fiber, then of A-fiber conduction. Graded concentrations of glycerol (25%, 50%, 75%, and 100%) were used in four rats with saphenous neuromas, which allowed selective blockade of spontaneous action potential generation and C-fiber conduction with minimal effect on A-fibers.

The neurophysiological mechanism of glycerol neurolysis appears to be a nonspecific conduction blockade of large and small fibers, which is established within minutes of its application. Spontaneous firing within damaged axons, which may play a role in a variety of cranial and peripheral nerve sensorimotor syndromes, is also exquisitely sensitive to glycerol application.

Restricted access

Kim J. Burchiel and Lisa C. Russell

✓ Thirty-five Sprague-Dawley rats with saphenous neuromas underwent acute microfilament recording in the proximal nerve. The effect of the potassium channel-blocking agents, tetraethylammonium bromide (TEA) and 4-aminopyridine, on spontaneous activity in A fibers terminating in the neuroma was observed. The effects of gallamine were also tested. Of the two channel-blocking agents, TEA reliably increased spontaneous firing in active fibers and initiated spontaneous activity in some fibers with no spontaneous baseline discharge. 4-Aminopyridine had no effect on baseline activity of either spontaneously active or quiescent fibers; however, it inhibited spontaneous activity induced by prior TEA treatment. Gallamine application produced effects similar to TEA in that spontaneous activity was dramatically increased. These results imply that a tonic potassium conductance is present in regenerating fibers in the neuroma and that this conductance moderates the tendency toward hyperexcitability and spontaneous firing. Spontanous activity in nociceptive afferent fibers may represent the mechanism of chronic pain and paresthesias that often accompany peripheral nerve injury. These results suggest that agents which either increase potassium conductance or selectively inhibit the sodium current in regenerating axons might be effective in the treatment of these chronic pain syndromes.

Restricted access

Kim J. Burchiel and Lisa C. Russell

✓ In 18 Sprague-Dawley rats, the left sciatic nerve was divided at the mid-femur level. Seven to 9 days later, microfilament recordings were made from the ipsilateral L-5 ventral root. Spontaneous activity in the ventral root, ranging from 0.1 to 6.1 Hz, was recorded in 12 of the 18 animals. Conduction velocity determinations showed this activity to be in A-beta and A-delta fibers. Recordings in 10 normal L-5 ventral roots from five control rats showed no spontaneous activity. In the rats with sciatic nerve division, the ongoing discharge appeared to originate in the cut end of the nerve since mechanical stimulation of the neuroma produced synchronous ventral root activity. Furthermore, cooling of the neuroma inhibited the spontaneous discharge, whereas with rewarming it returned. Spontaneous ventral root activity was also increased by systemic application of epinephrine. This activity was qualitatively similar to spontaneous activity that has been recorded in dorsal root microfilaments after peripheral nerve injury. The observation of an ongoing discharge in potentially nociceptive ventral root axons subsequent to nerve injury may be relevant to the mechanism of chronic pain of peripheral origin.

Restricted access

Kim J. Burchiel and Thomas K. Baumann

✓ The origin of trigeminal neuralgia (TN) appears to be vascular compression of the trigeminal nerve at the root entry zone; however, the physiological mechanism of this disorder remains uncertain. The authors obtained intraoperative microneurographic recordings from trigeminal ganglion neurons in a patient with TN immediately before percutaneous radiofrequency-induced gangliolysis. Their findings are consistent with the idea that the pain of TN is generated, at least in part, by an abnormal discharge within the peripheral nervous system.

Restricted access

Kim J. Burchiel

Restricted access

Brien Vlcek, Kim J. Burchiel and Thomas Gordon

✓ Subacute paraplegia progressing over 3 months due to spinal cord compression was the presenting symptom of tuberculous meningitis in this patient with a normal chest x-ray film and no radiological or autopsy evidence of Pott's vertebral tuberculosis. The obstructive myelopathy was the result of proliferative granulomatous meningitis. A review of the literature indicates that this is a very unusual presentation of tuberculous meningitis.

Restricted access

Editorial

Hyperglycemia

Kim J. Burchiel

Restricted access

Kim J. Burchiel

Restricted access

Kim J. Burchiel, Timothy J. Johans and Jose Ochoa

✓ Pain following suspected nerve injury was comprehensively evaluated with detailed examination including history', neurological evaluation, electrodiagnostic studies, quantitative sensory testing, thermography, anesthetic agents, and sympathetic nerve blocks. Forty-two surgically treated patients fell into four discrete groups: Group 1 patients had distal sensory neuromas treated by excision of the neuroma and reimplantation of the proximal nerve into muscle or bone marrow; Group 2 patients had suspected distal sensory neuromas in which the involved nerve was sectioned proximal to the injury site and reimplanted; Group 3 patients had proximal in-continuity neuromas of major sensorimotor nerves treated by external neurolysis; and Group 4 patients had proximal major sensorimotor nerve injuries at points of anatomical entrapment treated by external neurolysis and transposition, if possible. Patient follow-up monitoring from 2 to 32 months (average 11 months) was possible in 40 (95%) of 42 patients. Surgical success was defined as 50% or greater improvement in pain using the Visual Analog Scale or pain relief subjectively rated as either good or excellent, without postoperative narcotic usage. Overall, 16 (40%) of 40 patients met those criteria. Success rates varied as follows: 44% in 18 Group 1 patients, 40% in 10 Group 2 patients, 0% in five Group 3 patients, and 57% in seven Group 4 patients. Twelve (30%) of 40 patients were employed both pre- and postoperatively.

It is concluded that: 1) neuroma excision, neurectomy, and nerve release for injury-related pain of peripheral nerve origin yield substantial subjective improvement in a minority of patients; 2) external neurolysis of proximal mixed nerves is ineffective in relieving pain; 3) surgically proving the existence of a neuroma with confirmed excision may be preferable; 4) traumatic neuroma pain is only partly due to a peripheral source; 5) demographic and neurological variables do not predict success; 6) the presence of a discrete nerve syndrome and mechanical hyperalgesia modestly predict pain relief; 7) ongoing litigation is the strongest predictor of failure; and 8) change in work status is not a likely outcome.