Biomedical subjects

Eli Eliav

Publications and source records attributed to Eli Eliav.

22 records · Page 2Linked to original sources

PubMed2002

Large myelinated nerve fiber hypersensitivity in oral malignancy.

OBJECTIVES: The purpose of this study was to assess the sensory function of trigeminal nerve A-beta fibers in suspected soft tissue oral malignancies. STUDY DESIGN: Twenty-three patients referred for the evaluation of an oral lesion suspected of malignancy were included in the study. All lesions were classified as in, near, or out of the nerve territory containing the lesion. Within these subgroups we assessed the sensitivity of A-beta primary afferents to weak electrical currents applied bilaterally to regions innervated by 3 peripheral branches of the trigeminal nerve. The ratio of electrical detection thresholds from the affected and the unaffected side was calculated. Electrical detection threshold ratios were contrasted with the results of physical examination, radiographic imaging, and biopsy. RESULTS: For dermatomes containing the lesions, ratios were lower than 0.8 in 12 patients. Biopsy showed that the lesions in 10 of these 12 patients were malignant. No malignancy was found in the remaining 11 patients. CONCLUSIONS: A-beta primary afferent hypersensitivity is observed to occur in nerves exposed to soft tissue oral malignancy.

Adult↗

PubMed2002

Hemicrania continua.

Unilateral throbbing headaches may present similar signs and symptoms as dental pathology and are a diagnostic challenge for dental practitioners. Cases may be seen with a primary complaint of unilateral pain or referred by medical colleagues for exclusion of dental causes. In the present article the authors add a new case of hemicrania continua (HC), which is one such unilateral headache, and review the previously published cases. HC is relatively easy to treat since it responds completely to treatment with indomethacin. However, as is presented in this case, HC may masquerade as dental pain. Cases secondary to trauma, systemic disease, and nervous system pathology have been described in the literature, and the clinician must exclude these possible causes. A thorough knowledge of this entity is therefore essential.

Adult↗

PubMed1998

Sensory changes in the territory of the lingual and inferior alveolar nerves following lower third molar extraction.

Post-injury inflammation activates nociceptive systems and recruits normally non-nociceptive afferents into a pain processing role. During inflammation, Abeta low threshold mechanoreceptor afferents that usually mediate tactile sensation acquire properties of nociceptors, allowing them to participate in post-injury spontaneous pain and evoked abnormalities such as tenderness and pain to light touch. This study assessed the sensory consequences of post-injury inflammation following extraction of a single, lower third molar tooth. Extensive bilateral evaluations were performed in the territory of nerves assumed to be exposed to both inflammation and mechanical trauma, inflammation alone, or only the central consequences of peripheral inflammation. Testing at the distal termination of nerves assumed to be exposed to local inflammation (mental and lingual nerve territory) revealed decreased detection thresholds (P < 0.05) to electrical stimulation and to mechanical stimulation by sensitive, disposable filaments developed and validated for this application. Testing at sites of assumed inflammation and mechanical trauma (mental nerve territory) showed reduced pain thresholds to electrical stimulation. Thermal detection and pain thresholds were not altered at any location in patients, and no effects were observed in control subjects receiving only local anesthetic injections. These results in humans are consistent with recent experimental evidence that inflammatory processes alter the central consequence of activity in large-diameter Abeta touch primary afferents evoked under natural conditions by gentle mechanical stimulation. These effects result in hyperesthesia, increased sensitivity to light touch, and mechanical allodynia, pain evoked by normally innocuous stimulation of Abeta primary afferents.

Adolescent↗

PubMed1996

Abnormal discharge originates at the site of nerve injury in experimental constriction neuropathy (CCI) in the rat.

Rats with an experimental painful peripheral neuropathy created by placing loosely constrictive ligatures around the sciatic nerve (the CCI model) display heat-hyperalgesia on the affected limb. Pain threshold was studied using the paw withdrawal method. Electrophysiological recording from myelinated primary afferent axons revealed spontaneous impulse activity which originated at the site of nerve constriction. Overall 10.1 +/- 1.5% of the fibers sampled had spontaneous activity during the period 2-14 days post injury. The spontaneous activity fell into three patterns: (1) 'tonic' rhythmic pattern, in which the interval between successive spikes in a train was uniform, ranging from 25-50 ms (discharge rate 20-40 Hz); (2) interrupted, bursty or 'on-off' pattern, with variable silent period between high frequency bursts; and (3) 'irregular' ongoing pattern with random inter-spike intervals (5-15 Hz). There was a correlation between the prevalence and pattern of spontaneous activity, and the development of hyperalgesia post-injury. Axons trapped at the injury site including ones with and without spontaneous activity, became hyperexcitable to mechanical stimulation. The location of mechanosensitive spots progressively shifted over the period 2-14 days from the proximal to the distal part of the injury site. The spontaneous discharge of injured primary afferent fibers may contribute to abnormal sensation in these animals.

Animals↗