The "banana splitting DREZotomy": an atraumatic method to improve pain relief after dorsal root entry zone lesioning in brachial plexus injuries. Case series and tenets for the treatment.

BACKGROUND: The treatment of neuropathic deafferentation pain due to avulsion injuries of the brachial plexus is a major problem, albeit rare, in the neurosurgical practice. The aim of the paper is to present step-by-step the main principles of a surgical upgrade of the well-known Dorsal Root Entry Zone lesioning, that we named banana splitting DREZotomy. METHODS: A comparison is made among three groups of patients, two of which were treated following the classic techniques, while in the third no physical agent is applied to the spinal cord during surgery. RESULTS: The patients operated on following the well-established surgical procedures showed a short-term success rate around 70%, online with the data of the ongoing literature. The results with the banana-splitting technique, instead, have been astonishing both in terms of resolution of pain, absence of true complications and of unpleasant side effects. CONCLUSIONS: A purely dissective technical variant of the surgical procedure called DREZ lesioning has shown better results overcoming the 30% failures of all the reported series. The profound and permanent splitting of the posterior horn and the absence of any other component (heat propagation, radiofrequency, or dotted coagulation) are the major factors which may explain such outstanding results.

The reanimation of the elbow functions in avulsive injuries of the upper brachial plexus using the medial cord transfer: nuances of the technique and update.

OBJECTIVES: Report on a new transfer for the reinnervation of biceps and brachialis muscles after multilevel avulsive injuries of brachial plexus provided at least T1 is viable: the Medial Cord to Musculocutaneous (MCMc) and its variant, the Medial Cord to anterior Upper Trunk (MC-aUT). The MC-aUT is indicated in agenesia of musculocutaneous nerve and when a residual function in the biceps is present. The MCMc transfer would be unfeasible in the former and contraindicated in the latter. METHODS: Three hundred and five consecutive patients, classified according to the quality of hand function, are available for a long-term follow-up after reconstructive surgery. They had multiple cervical root avulsive injuries at two (C5-C6), three (C5-C6-C7) and four (C5-C6-C7-C8) levels. The reinnervation was obtained via an end-to-end transfer from two donor fascicles located in the medial cord (MC) and aimed at the flexor carpi ulnaris or the flexor digitorum profundus. RESULTS: These transfers have no failures and no complications when the hand shows a normal function. In the case of suboptimal conditions of the hand, the technique is more challenging, but still has many satisfactory results. In the four-root avulsive injuries, on the contrary, strong limitations suggest that different strategies should be preferred. EMG shows a reinnervation in both biceps and brachialis muscles and this accounts for the quality of results. Tendon transfers for wrist and finger dorsiflexion, when required, remain unencumbered. DISCUSSION: The procedures are safe, effective and easily feasible. The ideal candidate has a C5-C6 injury and a normal hand function.

The Masseteric-Facial Anastomosis With Intratemporal Translocation of the Facial Nerve: Step-by-Step Technique and Results.

BACKGROUND: In the absence of a viable proximal nerve stump, damaged after surgical procedures around the skull base, numerous techniques for facial reanimation have been developed over time, aiming to restore baseline symmetry and active mimicry. OBJECTIVE: To report experience using the masseteric nerve as a direct transfer to the facial nerve rerouted after intratemporal translocation. This paper illustrates the main steps of the technique and the quality of results. METHODS: Eleven patients were treated with a masseteric direct transfer to the facial nerve. Its extratemporal rerouting toward the zygoma allowed tension-free coaptation between donor and recipient nerves. RESULTS: Of the 11 patients, 8 had a good to excellent recovery, showing different patterns of time and scores, according to age, surgical timing, and masseteric nerve function quality. The return of activity in the frontalis muscle, never obtained after reinnervation via the hypoglossal nerve, is of particular interest. The quality of the smile can be improved with re-education and practice but remains under volitional control. A true emotional response is still lacking. CONCLUSION: The masseteric nerve is an excellent alternative to the hypoglossal nerve and can reinnervate the whole territory of the facial nerve rerouted after intratemporal translocation. The overall results are remarkable, but the low quality of the trigeminal nerve, eventually affected by the first surgery, may be an important limitation. Even if the patients appear more at ease in re-education than with other techniques, a fully natural facial expression remains impossible to obtain.

Dorsal root entry zone lesion: nuances of the technique and long-term results.

The treatment of deafferentation pain is a primary goal of a referral center for peripheral nerve surgery. DREZ is an important asset in the neurosurgeon's armamentarium. The surgical technique and long-term results are analyzed in two series, with or without intraoperative monitoring (IOM). DREZotomy is highly effective in lumbar root avulsive injuries but is ineffective in resolving pain due to spinal cord injuries. Cervical DREZotomy for cancer pain is not superior to intrathecal morphine. In brachial plexus avulsive injuries, the largest series shows a 74% success rate, but the efficacy of the procedure is lost over time. No relevant difference has been observed since the introduction of IOM. The video can be found here: https://youtu.be/uG_kkQj5m1U.

Effect of mild hypothermic cardiopulmonary bypass on the amplitude of somatosensory-evoked potentials.

BACKGROUND: Several neurophysiological techniques are used to intraoperatively assess cerebral functioning during surgery and intensive care, but the introduction of hypothermia as a means of intraoperative neuroprotection has brought their reliability into question. The present study aimed to evaluate the effect of mild hypothermia on somatosensory-evoked potentials' (SSEPs) amplitude and latency in a cohort of cardiopulmonary bypass (CPB) patients as the temperature reached the steady-state. MATERIALS AND METHODS: The amplitude and latency of 4 different SSEP signals--N9, N13, P14/N18 interpeak, and N20/P25--were evaluated retrospectively in 84 patients undergoing CPB during normothermic (36°C±0.43°C) and mild hypothermic (32°C±1.38°C) conditions. SSEPs were recorded in normothermia immediately after the induction of anesthesia and in hypothermia as the temperature reached its steady-state, specifically, when the nasopharyngeal temperature was equivalent to the rectal temperature (±0.5°C). A paired-samples t test was performed for each SSEP to test the differences in latencies and amplitudes between normothermic and hypothermic conditions. RESULTS: Compared with normothermia, hypothermia not only significantly increased the latency of all SSEPs, N9 (P<0.001), N13 (P<0.001), P14/N18 (P<0.001), and N20/P25 (P<0.001), but also the amplitude of N9 (P<0.001) and N20/P25 (P<0.001). CONCLUSIONS: The increased amplitude in particularly of cortical SSEPs (N20/P25), detected specifically during steady-state hypothermia, seems to support the clinical utility of this methodology in monitoring the brain function not only during cardiac surgery with CPB, but also in other settings like therapeutic hypothermia procedures in an intensive care unit.

Correlation of transcranial color Doppler to n20 somatosensory evoked potential detects ischemic penumbra in subarachnoid hemorrhage.

BACKGROUND: Normal subjects present interhemispheric symmetry of middle cerebral artery (MCA) mean flow velocity and N20 cortical somatosensory evoked potential (SSEP). Subarachnoid haemorrhage (SAH) can modify this pattern, since high regional brain vascular resistances increase blood flow velocity, and impaired regional brain perfusion reduces N20 amplitude. The aim of the study is to investigate the variability of MCA resistances and N20 amplitude between hemispheres in SAH. METHODS: Measurements of MCA blood flow velocity (vMCA) by transcranial color-Doppler and median nerve SSEP were bilaterally performed in sixteen patients. MCA vascular changes on the compromised hemisphere were calculated as a ratio of the reciprocal of mean flow velocity (1/vMCA) to contralateral value and correlated to the simultaneous variations of interhemispheric ratio of N20 amplitude, within each subject. Data were analysed with respect to neuroimaging of MCA supplied areas. RESULTS: Both interhemispheric ratios of 1/vMCA and N20 amplitude were detected >0.65 (p <0,01) in patients without neuroimages of injury. Both ratios became <0.65 (p <0.01) when patients showed unilateral images of ischemic penumbra and returned >0.65 if penumbra disappeared. The two ratios no longer correlated after structural lesion developed, as N20 detected in the damaged side remained pathological (ratio <0.65), whereas 1/vMCA reverted to symmetric interhemispheric state (ratio >0.65), suggesting a luxury perfusion. CONCLUSION: Variations of interhemispheric ratios of MCA resistance and cortical N20 amplitude correlate closely in SAH and allow identification of the reversible ischemic penumbra threshold, when both ratios become <0.65. The correlation is lost when structural damage develops.

Ill-lighting syndrome: prevalence in shift-work personnel in the anaesthesiology and intensive care department of three Italian hospitals.

BACKGROUND: Light is one of the most important factors in our interaction with the environment; it is indispensable to visual function and neuroendocrine regulation, and is essential to our emotional perception and evaluation of the environment. Previous studies have focussed on the effects of prolonged anomalous exposure to artificial light and, in the field of work-related illness. Studies have been carried out on shift-work personnel, who are obliged to experience alterations in the physiological alternation of day and night, with anomalous exposure to light stimuli in hours normally reserved for sleep. In order to identify any signs and symptoms of the so-called ill-lighting syndrome, we carried out a study on a sample of anaesthesiologists and nurses employed in the operating theatres and Intensive Care Departments of three Italian hospitals. We measured the subjective emotional discomfort (stress) experienced by these subjects, and its correlation with environmental discomfort factors, in particular the level of lighting, in their workplace. METHODS: We used a questionnaire developed by the Scandinavian teams who investigated Sick-Building Syndrome, that was self-administered on one day in the environments where the degree of illumination was measured according to UNIEN12464-1 regulations. RESULTS: Upon comparison of the types of exposure with the horizontal luminance values (lux) measured (< 700 lux, between 1000-1500 lux, > 1500 lux) and the degree of stress reported, (Intensive Care: mean stress = 55.8%, high stress = 34.6%; Operating Theatres: mean stress = 51.5%, high stress = 33.8%), it can be observed that the percentage of high stress was reduced as the exposure to luminance was increased, although this finding was not statistically significant. CONCLUSION: We cannot share other authors' enthusiasm regarding the effects on workers well-being correlated to the use of fluorescent lighting. The stress level of our workers was found to be more heavily influenced by their familial and working conditions, irrespective of the ambient light stimulus.

Brain function monitoring during off-pump cardiac surgery: a case report.

BACKGROUND: Early postoperative stroke is an adverse syndrome after coronary bypass surgery. This report focuses on overcoming of cerebral ischemia as a result of haemodynamic instability during heart enucleation in off-pump procedure. CASE PRESENTATION: A 67 year old male patient, Caucasian race, with a body mass index of 28, had a recent non-Q posterolateral myocardial infarction one month before and recurrent instable angina. His past history includes an uncontrolled hypertension, dyslipidemia, insulin dependent diabetes mellitus, epiaortic vessel stenosis. The patient was scheduled for an off-pump procedure and monitored with bilateral somatosensory evoked potentials, whose alteration signalled the decrement of the cardiac index during operation.The somatosensory evoked potentials appeared when the blood pressure was increased with a pharmacological treatment. CONCLUSION: During the off-pump coronary bypass surgery, a lower cardiac index, predisposes patients, with multiple stroke risk factors, to a reduction of the cerebral blood flow. Intraoperative somatosensory evoked potentials monitoring provides informations about the functional status of somatosensory cortex to reverse effects of brain ischemia.