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G Talamonti

Publications and source records attributed to G Talamonti.

27 records · Page 2Linked to original sources
PubMed1991

Experimental studies on spinal cord injuries in the last fifteen years.

Experimental studies on spinal cord (SC) injuries published from 1975 to 1989 in some of the most widely circulating neurosurgical journals were reviewed. The relatively large number of animal species utilized as well as the intensely variable dynamic or static methods employed to induce SC injury represent elements of confusion more than objective necessities in this field of research. In fact, the objective of SC injury research should be to solve the problem of severe SC injuries by either preventing and/or repairing SC damage, rather than looking for modalities to provoke a large spectrum of SC injuries with the result of establishing a correlation between for example, the clinical picture and trauma magnitude. It should be time to study all variables and treatments mainly in only one experimental model. The rat with a permanent paraplegia should represent such a model; the abdominal aorta occlusion for 45 minutes, distal to the renal arteries in rabbits should be the experimental model of choice for ischaemia. If a significant result, such as reversing permanent paraplegia, were obtained in rats, it would be logical to repeat the study in higher mammals and if successful, in humans. For the last decade of this century it is necessary to further study all the mechanisms implied in secondary SC damage as well as to attempt to repair definitive SC damage by using grafts and enhancing the potential regenerative ability of the SC with known and new growth factors. Presently, methylprednisolone, dexametasone, thiopental, naloxone, and hypothermia seem to have some clinical potentials that require studies in humans.

Animals↗
PubMed1990

Value of magnetic resonance imaging in spontaneous extradural spinal hematoma due to vascular malformation: case report.

A case of spinal cord compression due to spontaneous extradural spinal hematoma is reported. A spinal arteriovenous malformation was suspected on the basis of magnetic resonance imaging. Early surgical exploration allowed a complete neurological recovery. The vascular malformation was histopathologically confirmed. The role of magnetic resonance imaging in the evaluation of acute spinal cord compression syndromes is stressed.

Arteriovenous Malformations↗
PubMed1989

Spinal cord stimulation (SCS) in the treatment of postherpetic pain.

SCS is considered to be of poor value in treating postherpetic pain. We have retrospectively analyzed the results obtained in 10 patients suffering from postherpetic neuralgia. An epidural electrode was implanted, aiming the tip in a position where stimulation could produce paraesthesiae over the painful area. At the end of the test period 6 out of 10 patients reporting a mean analgesia of 52.5% underwent a permanent implant. At mean follow-up (15 months) all the 6 patients were still reporting a satisfactory pain relief (74% of mean analgesia). These figures remained unchanged at the next follow-ups (max 46 months). The result of SCS in our patients, although positive in only 60% of them, are remarkably stable with time. We therefore recommend a percutaneous test trial of SCS in every case of postherpetic neuralgia resistent to medical treatment.

Aged↗
PubMed1989

Spinal cord stimulation (SCS) in deafferentation pain.

Spinal cord stimulation is considered to be ineffective in relieving deafferentation pain. We have retrospectively analyzed the results obtained in a series of 41 patients. Sixteen suffered from pain associated with an incomplete traumatic spinal lesion, 15 from a posttherapeutic neuralgia, and 10 from pain due to root and/or nerve damage. At the end of the test period, 43.7% of the patients with paraplegic pain, (40% of those with peripheral deafferentation pain and 66.6% of the ones with postherapeutic neuralgia), reported satisfactory pain relief and were connected to a chronic stimulation system. At mean follow-up (15 months), only 20% of the patients of the first two groups reported sufficient pain relief. In the postherapeutic group the figure of responders was unchanged. The mean analgesia achieved was 70%. From this analysis we conclude that the results achieved in the postherapeutic pain patients, although positive in only 66% of them, are remarkably stable with time. Therefore, we recommend a percutaneous test trial of SCS in every case of postherapeutic pain resistant to medical treatment.

Adult↗
PubMed1989

Spinal cord stimulation (SCS) in spastic hemiparesis.

Thirteen patients with post-stroke spastic hemiparesis underwent a percutaneous test trial of spinal cord stimulation (SCS) in order to modify their motor disturbances. Clinical evaluation based on Albert's motor scale and neurophysiological evaluation consisting of surface EMG during voluntary, involuntary, and reflex motor activity were performed before and during SCS. At the end of the test period, eight patients showed a significant improvement in their motor performance. The EMG analysis confirmed the clinical data. SCS was followed by a reduction or disappearance of synergic coactivation with better agonist-antagonist coordination, a decrease of clonus both in duration and spreading, and better endurance. The effect on motor control did not increase with time after the first month of SCS, but was long lasting (mean follow-up: 2 years). There was a correlation between sensory deficit and motor outcome suggesting that the enhancement of sensory input put into play by SCS and the consequent development of new sensory-motor integration might be responsible for the improvement in motor performance.

Adult↗
PubMed1988

The third nerve transection and regeneration in rats with preliminary results on the sixth nerve transection and regeneration in guinea pigs.

The relationship between the phenomenon of the nonselective reinnervation and the functional recovery after section and repair of the highly organized third cranial nerve motor system in rats was studied. The same relationship after section and repair of the more simply organized sixth cranial nerve motor system in guinea pigs is presented as preliminary results. Anatomical demonstration of nonselective reinnervation was obtained by injecting horseradish peroxidase (HRP) into the extraocular muscles. A bilateral reinnervation of previously ipsilateral innervated muscles both in the third and the sixth nerve was interpreted as a plastic response of the brain stem neurons to the nerve injury. Functional recovery, evaluated by measuring with an infrared light technique the horizontal and vertical vestibulo-ocular reflexes, was excellent for the rectus lateralis muscle while it was relatively poor i.e. partial for the muscles depending on the third nerve. These data suggest that one of the most important factors influencing the functional recovery after section and repair of a peripheral nerve is the complexity of the nerve motor system organization.

Abducens Nerve↗
PubMed1987

Oculomotor nerve regeneration in rats. Functional, histological, and neuroanatomical studies.

To study oculomotor nerve regeneration in rats, the oculomotor nerve was approached microsurgically and was sectioned at the base of the skull. The nerve stumps were reapproximated and affixed with a plasma clot in Group I animals and were separated by a gap in Group II animals. Visceral eye motility was evaluated weekly between 1 day and 40 weeks after surgery by recording the pupillary diameter under standardized photic stimulation. Somatic eye motility was assessed after 26 weeks by measuring the ocular displacement evoked by vestibular stimulation in the horizontal and vertical planes. Nerve regeneration was documented histologically and morphometrically at 8, 16, and 40 weeks after section. The selectivity of axonal regeneration to the extraocular muscles was investigated after 26 weeks by mapping (with injection of retrograde horseradish peroxidase) the motoneurons that supplied each reinnervated muscle. Between 6 and 20 weeks after section, the pupil diameter showed a progressive reduction in Group I rats, and no changes were observed in Group II rats. Compared with normal rats, the amplitude of horizontal and vertical ocular displacements was decreased, respectively, by 30% and 45% in Group I and by 65% and 80% in Group II. In Group I rats, the vestibular stimulation in the horizontal plane evoked anomalous eye movements with vertical components. On histological examination, regenerated nerves showed a progressive increase of axonal diameter and myelin-sheath thickness. Reinnervated muscles were associated with a less specific, bilateral representation in the midbrain compared with normal muscles, which have unilateral representation. The changes of the somatotopic organization were interpreted as being the result of the misdirected regrowth of axons in the postlesional nerve stump and of the collateral sprouting in the midbrain.

Animals↗
PubMedDate not supplied

Surgical treatment of 100 single brain metastases. Analysis of the results.

The authors report their personal series of 100 consecutive surgically treated single brain metastases between 1981 and 1988. Patients selection was decided with respect to general and neurological conditions and to primary cancer development. Resection was mostly radical, postoperative mortality rate was 6% and neurological improvement was obtained in 73% of cases. Mean follow-up was 15 months (min. 12, max. 60). The overall median survival time was 13 months. The survival rate was studied with respect to age, lesion site, preoperative syndrome, primary cancer, cause of death and radiotherapy. On the base of their experience the Authors would stress that a better patients selection can further reduce the mortality rate.

Adult↗