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Armando E Giuliano - One of the best experts on this subject based on the ideXlab platform.
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surgical complications associated with sentinel lymph node dissection slnd plus axillary lymph node dissection compared with slnd alone in the american college of surgeons oncology group trial z0011
Journal of Clinical Oncology, 2007Co-Authors: Anthony Lucci, Linda M Mccall, Peter D Beitsch, Patrick W Whitworth, Douglas S Reintgen, P Blumencranz, Marilyn A Leitch, Sukumal Saha, Kelly K Hunt, Armando E GiulianoAbstract:Purpose The American College of Surgeons Oncology Group trial Z0011 was a prospective, randomized, multicenter trial comparing overall survival between patients with positive sentinel lymph nodes (SLNs) who did and did not undergo axillary lymph node dissection (ALND). The current study compares complications associated with SLN dissection (SLND) plus ALND, versus SLND alone. Patients and Methods From May 1999 to December 2004, 891 patients were randomly assigned to SLND + ALND (n = 445) or SLND alone (n = 446). Information on wound infection, axillary seroma, Paresthesia, brachial plexus injury (BPI), and lymphedema was available for 821 patients. Results Adverse surgical effects were reported in 70% (278 of 399) of patients after SLND + ALND and 25% (103 of 411) after SLND alone (P ≤ .001). Patients in the SLND + ALND group had more wound infections (P ≤ .0016), seromas (P ≤ .0001), and Paresthesias (P ≤ .0001) than those in the SLND-alone group. At 1 year, lymphedema was reported subjectively by 13% (3...
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surgical complications associated with sentinel lymph node dissection slnd plus axillary lymph node dissection compared with slnd alone in the american college of surgeons oncology group trial z0011
Journal of Clinical Oncology, 2007Co-Authors: Anthony Lucci, Linda M Mccall, Peter D Beitsch, Patrick W Whitworth, Douglas S Reintgen, P Blumencranz, Marilyn A Leitch, Sukumal Saha, Kelly K Hunt, Armando E GiulianoAbstract:PURPOSE: The American College of Surgeons Oncology Group trial Z0011 was a prospective, randomized, multicenter trial comparing overall survival between patients with positive sentinel lymph nodes (SLNs) who did and did not undergo axillary lymph node dissection (ALND). The current study compares complications associated with SLN dissection (SLND) plus ALND, versus SLND alone. PATIENTS AND METHODS: From May 1999 to December 2004, 891 patients were randomly assigned to SLND + ALND (n = 445) or SLND alone (n = 446). Information on wound infection, axillary seroma, Paresthesia, brachial plexus injury (BPI), and lymphedema was available for 821 patients. RESULTS: Adverse surgical effects were reported in 70% (278 of 399) of patients after SLND + ALND and 25% (103 of 411) after SLND alone (P
Jan Holsheimer - One of the best experts on this subject based on the ideXlab platform.
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the effect of pulse width and contact configuration on Paresthesia coverage in spinal cord stimulation
Neurosurgery, 2011Co-Authors: Jan Holsheimer, Jan R Buitenweg, Paul De Sutter, Ljubomir Manola, Bart NuttinAbstract:BACKGROUND: In spinal cord stimulation for the management of chronic, intractable pain, a satisfactory analgesic effect can be obtained only when the stimulation-induced Paresthesias cover all painful body areas completely or partially. OBJECTIVE: To investigate the effect of stimulus pulse width (PW) and contact configuration (CC) on the area of Paresthesia (PA), perception threshold (VPT), discomfort threshold (VDT), and usage range (UR) in spinal cord stimulation. METHODS: Chronic pain patients were tested during a follow-up visit. They were stimulated monopolarly and with the CC giving each patient the best analgesia. VPT, VDT, and UR were determined for PWs of 90, 210, and 450 microseconds. The Paresthesia contours at VDT were drawn on a body map and digitized; PA was calculated; and its anatomic composition was described. The effects of PW and CC on PA, VPT, VDT, and UR were tested statistically. RESULTS: Twenty-four of 31 tests with low thoracic stimulation and 8 of 9 tests with cervical stimulation gave a significant extension of PA at increasing PW. In 14 of 18 tests (low thoracic), a caudal extension was obtained (primarily in L5-S2). In cervical stimulation the extension was predominantly caudal as well. In contrast to VPT and VDT, UR is not significantly different when stimulating with any CC. CONCLUSION: PA extends caudally with increasing PW. The mechanism includes that the larger and smaller dorsal column fibers have a different mediolateral distribution and that smaller dorsal column fibers have a smaller UR and can be activated only when PW is sufficiently large. A similar effect of CC on PA is unlikely as long as electrodes with a large intercontact distance are applied.
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effects of electrode positioning on perception threshold and Paresthesia coverage in spinal cord stimulation
Neuromodulation, 2007Co-Authors: Jan Holsheimer, Y N Khan, S S Raza, A E KhanAbstract:Objectives. This pilot study aims to validate the hypothesis that a smaller distance between SCS lead and spinal cord results in more extensive Paresthesia and less energy consumption. Materials and Methods. After insertion of a percutaneous SCS lead in patients with chronic pain (condition A), a first catheter was temporarily placed alongside the lead (condition B) and next, a second catheter was placed on the other side of the lead (condition C). In all three conditions Paresthesia coverage, perception threshold of Paresthesia (PT) and maximum comfortable stimulus amplitude (MC) were determined and the catheters were subsequently removed. Results. Paresthesia coverage in all 6 patients was increased markedly in condition C when compared to condition A, whereas the mean values of PT, MC and therapeutic range (MC/PT) dropped by 22%, 14% and 13%, respectively. Conclusions. The results suggest that Paresthesia coverage is increased when the space between the SCS lead and spinal cord gets smaller, whereas PT and energy consumption are reduced.
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clinical evaluation of Paresthesia steering with a new system for spinal cord stimulation
Neurosurgery, 1998Co-Authors: Jan Holsheimer, Paul De Sutter, Bart Nuttin, G W King, W A Wesselink, Jan GybelsAbstract:OBJECTIVE: The goal was to evaluate, in a clinical study, the predicted performance of the transverse tripolar system for spinal cord stimulation, particularly the steering of Paresthesia, Paresthesia coverage, and the therapeutic range of stimulation. METHODS: Six transverse tripolar electrodes were implanted in the lower thoracic region in four patients experiencing chronic neuropathic pain. Electrode positions, relative to the spinal cord, were estimated from computed tomographic scans. A dual-channel stimulator was used for initial percutaneous tests, and an implanted single-channel stimulator was used for follow-up test sessions. Nine "balance" settings and several cathode-anode combinations were used with the dual-channel and single-channel stimulator, respectively. In each test, the increase of Paresthesia coverage from the perception threshold to the discomfort threshold was registered on a body map and the corresponding voltages were recorded. RESULTS: Paresthesia steering occurred in all but one patient. The normalized steering score, enabling quantitative comparisons of Paresthesia steering among tests and patients, showed that maximum Paresthesia steering occurred when the electrode was at least 3 mm dorsal to the spinal cord and centered <2 mm from its midline. Paresthesia coverage included 70 to 100% of the body up to the electrode level, unless the electrode migrated or had broken wires. The therapeutic range, defined as the discomfort/perception of Paresthesia threshold ratio, varied from 1.6 to 4.0. CONCLUSION: The clinical performance of transverse tripolar stimulation is in accordance with the characteristics predicted by computer modeling. It enables finer control of Paresthesia than that achieved by polarity changes in conventional spinal cord stimulation systems.
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Clinical evaluation of Paresthesia steering with a new system for spinal cord stimulation.
Neurosurgery, 1998Co-Authors: Jan Holsheimer, Bart Nuttin, G W King, W A Wesselink, Jan Gybels, P. De SutterAbstract:OBJECTIVE: The goal was to evaluate, in a clinical study, the predicted performance of the transverse tripolar system for spinal cord stimulation, particularly the steering of Paresthesia, Paresthesia coverage, and the therapeutic range of stimulation. METHODS: Six transverse tripolar electrodes were implanted in the lower thoracic region in four patients experiencing chronic neuropathic pain. Electrode positions, relative to the spinal cord, were estimated from computed tomographic scans. A dual-channel stimulator was used for initial percutaneous tests, and an implanted single-channel stimulator was used for follow-up test sessions. Nine "balance" settings and several cathode-anode combinations were used with the dual-channel and single-channel stimulator, respectively. In each test, the increase of Paresthesia coverage from the perception threshold to the discomfort threshold was registered on a body map and the corresponding voltages were recorded. RESULTS: Paresthesia steering occurred in all but one patient. The normalized steering score, enabling quantitative comparisons of Paresthesia steering among tests and patients, showed that maximum Paresthesia steering occurred when the electrode was at least 3 mm dorsal to the spinal cord and centered
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effect of anode cathode configuration on Paresthesia coverage in spinal cord stimulation
Neurosurgery, 1997Co-Authors: Jan Holsheimer, W A WesselinkAbstract:OBJECTIVE: To provide a theoretical basis for the selection of the anode-cathode configuration in spinal cord stimulation for the management of pain when one percutaneous epidural electrode or two electrodes in parallel are used. METHODS: A computer model of spinal cord stimulation at T8-T9 was used to calculate the dorsal column areas recruited in stimulation by various configurations used in clinical practice. RESULTS: Tripolar (or bipolar) stimulation by a single electrode, symmetrically placed over the dorsal columns, recruits the largest area and will give the widest Paresthesia coverage. Stimulation by two symmetrically placed electrodes connected in parallel to a single channel pulse generator may give similar results, because of their generally smaller distance from the spinal cord, but a summation effect does not exist. A smaller dorsal column area is activated when two offset electrodes are used. An electrode placed laterally or transverse bipolar stimulation results in unilateral, usually segmentary, Paresthesia. CONCLUSIONS: The relative positions of cathodes and anodes and their distance from the spinal cord are the major determinants of dorsal column/dorsal root activation and Paresthesia distribution. The large interpatient variability of the intraspinal geometry is the main cause of differences in Paresthesia coverage among patients having optimally placed electrode(s). Changes of Paresthesia coverage over time are more probable when multiple electrodes are used.
Anthony Lucci - One of the best experts on this subject based on the ideXlab platform.
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surgical complications associated with sentinel lymph node dissection slnd plus axillary lymph node dissection compared with slnd alone in the american college of surgeons oncology group trial z0011
Journal of Clinical Oncology, 2007Co-Authors: Anthony Lucci, Linda M Mccall, Peter D Beitsch, Patrick W Whitworth, Douglas S Reintgen, P Blumencranz, Marilyn A Leitch, Sukumal Saha, Kelly K Hunt, Armando E GiulianoAbstract:Purpose The American College of Surgeons Oncology Group trial Z0011 was a prospective, randomized, multicenter trial comparing overall survival between patients with positive sentinel lymph nodes (SLNs) who did and did not undergo axillary lymph node dissection (ALND). The current study compares complications associated with SLN dissection (SLND) plus ALND, versus SLND alone. Patients and Methods From May 1999 to December 2004, 891 patients were randomly assigned to SLND + ALND (n = 445) or SLND alone (n = 446). Information on wound infection, axillary seroma, Paresthesia, brachial plexus injury (BPI), and lymphedema was available for 821 patients. Results Adverse surgical effects were reported in 70% (278 of 399) of patients after SLND + ALND and 25% (103 of 411) after SLND alone (P ≤ .001). Patients in the SLND + ALND group had more wound infections (P ≤ .0016), seromas (P ≤ .0001), and Paresthesias (P ≤ .0001) than those in the SLND-alone group. At 1 year, lymphedema was reported subjectively by 13% (3...
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surgical complications associated with sentinel lymph node dissection slnd plus axillary lymph node dissection compared with slnd alone in the american college of surgeons oncology group trial z0011
Journal of Clinical Oncology, 2007Co-Authors: Anthony Lucci, Linda M Mccall, Peter D Beitsch, Patrick W Whitworth, Douglas S Reintgen, P Blumencranz, Marilyn A Leitch, Sukumal Saha, Kelly K Hunt, Armando E GiulianoAbstract:PURPOSE: The American College of Surgeons Oncology Group trial Z0011 was a prospective, randomized, multicenter trial comparing overall survival between patients with positive sentinel lymph nodes (SLNs) who did and did not undergo axillary lymph node dissection (ALND). The current study compares complications associated with SLN dissection (SLND) plus ALND, versus SLND alone. PATIENTS AND METHODS: From May 1999 to December 2004, 891 patients were randomly assigned to SLND + ALND (n = 445) or SLND alone (n = 446). Information on wound infection, axillary seroma, Paresthesia, brachial plexus injury (BPI), and lymphedema was available for 821 patients. RESULTS: Adverse surgical effects were reported in 70% (278 of 399) of patients after SLND + ALND and 25% (103 of 411) after SLND alone (P
W A Wesselink - One of the best experts on this subject based on the ideXlab platform.
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clinical evaluation of Paresthesia steering with a new system for spinal cord stimulation
Neurosurgery, 1998Co-Authors: Jan Holsheimer, Paul De Sutter, Bart Nuttin, G W King, W A Wesselink, Jan GybelsAbstract:OBJECTIVE: The goal was to evaluate, in a clinical study, the predicted performance of the transverse tripolar system for spinal cord stimulation, particularly the steering of Paresthesia, Paresthesia coverage, and the therapeutic range of stimulation. METHODS: Six transverse tripolar electrodes were implanted in the lower thoracic region in four patients experiencing chronic neuropathic pain. Electrode positions, relative to the spinal cord, were estimated from computed tomographic scans. A dual-channel stimulator was used for initial percutaneous tests, and an implanted single-channel stimulator was used for follow-up test sessions. Nine "balance" settings and several cathode-anode combinations were used with the dual-channel and single-channel stimulator, respectively. In each test, the increase of Paresthesia coverage from the perception threshold to the discomfort threshold was registered on a body map and the corresponding voltages were recorded. RESULTS: Paresthesia steering occurred in all but one patient. The normalized steering score, enabling quantitative comparisons of Paresthesia steering among tests and patients, showed that maximum Paresthesia steering occurred when the electrode was at least 3 mm dorsal to the spinal cord and centered <2 mm from its midline. Paresthesia coverage included 70 to 100% of the body up to the electrode level, unless the electrode migrated or had broken wires. The therapeutic range, defined as the discomfort/perception of Paresthesia threshold ratio, varied from 1.6 to 4.0. CONCLUSION: The clinical performance of transverse tripolar stimulation is in accordance with the characteristics predicted by computer modeling. It enables finer control of Paresthesia than that achieved by polarity changes in conventional spinal cord stimulation systems.
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Clinical evaluation of Paresthesia steering with a new system for spinal cord stimulation.
Neurosurgery, 1998Co-Authors: Jan Holsheimer, Bart Nuttin, G W King, W A Wesselink, Jan Gybels, P. De SutterAbstract:OBJECTIVE: The goal was to evaluate, in a clinical study, the predicted performance of the transverse tripolar system for spinal cord stimulation, particularly the steering of Paresthesia, Paresthesia coverage, and the therapeutic range of stimulation. METHODS: Six transverse tripolar electrodes were implanted in the lower thoracic region in four patients experiencing chronic neuropathic pain. Electrode positions, relative to the spinal cord, were estimated from computed tomographic scans. A dual-channel stimulator was used for initial percutaneous tests, and an implanted single-channel stimulator was used for follow-up test sessions. Nine "balance" settings and several cathode-anode combinations were used with the dual-channel and single-channel stimulator, respectively. In each test, the increase of Paresthesia coverage from the perception threshold to the discomfort threshold was registered on a body map and the corresponding voltages were recorded. RESULTS: Paresthesia steering occurred in all but one patient. The normalized steering score, enabling quantitative comparisons of Paresthesia steering among tests and patients, showed that maximum Paresthesia steering occurred when the electrode was at least 3 mm dorsal to the spinal cord and centered
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Estimation of fiber diameters in the spinal dorsal columns from clinical data
IEEE Transactions on Biomedical Engineering, 1998Co-Authors: W A Wesselink, G W King, J. Holsheimer, B. Nuttin, H.b.k. Boom, J.m. Gybels, P. De SutterAbstract:Lack of human morphometric data regarding the largest nerve fibers in the dorsal columns (DCs) of the spinal cord has lead to the estimation of the diameters of these fibers from clinical data retrieved from patients with a new spinal cord stimulation (SCS) system. These patients indicated the perception threshold of stimulation induced Paresthesia in various body segments, while the stimulation amplitude was increased. The fiber diameters were calculated with a computer model, developed to calculate the effects of SCS on spinal nerve fibers. This computer model consists of two parts: (1) a three-dimensional (3-D) volume conductor model of a spinal cord segment in which the potential distribution due to electrical stimulation is calculated and (2) an electrical equivalent cable model of myelinated nerve fiber, which uses the calculated potential field to determine the threshold stimulus needed for activation. It is shown that the largest fibers in the medial DCs are significantly smaller than the largest fibers in the lateral parts. This finding is in accordance with the fiber distribution in cat, derived from the corresponding propagation velocities. Moreover, it is shown that the mediolateral increase in fiber diameter is mainly confined to the lateral parts of the DCs. Implementation of this mediolateral fiber diameter distribution of the DCs in the computer model enables the prediction of the recruitment order of dermatomal Paresthesias following increasing electrical stimulation amplitude.
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effect of anode cathode configuration on Paresthesia coverage in spinal cord stimulation
Neurosurgery, 1997Co-Authors: Jan Holsheimer, W A WesselinkAbstract:OBJECTIVE: To provide a theoretical basis for the selection of the anode-cathode configuration in spinal cord stimulation for the management of pain when one percutaneous epidural electrode or two electrodes in parallel are used. METHODS: A computer model of spinal cord stimulation at T8-T9 was used to calculate the dorsal column areas recruited in stimulation by various configurations used in clinical practice. RESULTS: Tripolar (or bipolar) stimulation by a single electrode, symmetrically placed over the dorsal columns, recruits the largest area and will give the widest Paresthesia coverage. Stimulation by two symmetrically placed electrodes connected in parallel to a single channel pulse generator may give similar results, because of their generally smaller distance from the spinal cord, but a summation effect does not exist. A smaller dorsal column area is activated when two offset electrodes are used. An electrode placed laterally or transverse bipolar stimulation results in unilateral, usually segmentary, Paresthesia. CONCLUSIONS: The relative positions of cathodes and anodes and their distance from the spinal cord are the major determinants of dorsal column/dorsal root activation and Paresthesia distribution. The large interpatient variability of the intraspinal geometry is the main cause of differences in Paresthesia coverage among patients having optimally placed electrode(s). Changes of Paresthesia coverage over time are more probable when multiple electrodes are used.
Alan D L Sihoe - One of the best experts on this subject based on the ideXlab platform.
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incidence of chest wall Paresthesia after needlescopic video assisted thoracic surgery for palmar hyperhidrosis
European Journal of Cardio-Thoracic Surgery, 2005Co-Authors: Alan D L Sihoe, Clement S K Cheung, Kinhoi ThungAbstract:Objective: Chest wall Paresthesia is a reported sequela of thoracotomy and Video-Assisted Thoracic Surgery (VATS) which is distinct from wound pain. Although needlescopic VATS confers less post-operative pain and better cosmesis, the incidence of Paresthesia after needlescopic VATS has not been quantified. Methods: For homogeneity of the patient cohort, we studied 50 patients who received bilateral needlescopic VATS sympathectomy (T2-T4 excision) for palmar hyperhidrosis using 2 or 3 mm instruments during a 36-month period at a single institute. A standard questionnaire was administered by telephone interview, with 34 patents responding (68.0%). The median post-operative observation time was 16.5 months (range: 10-40 months). Collected data were compared with a historical group who received conventional VATS using 10mm ports. Results: Paresthetic discomfort distinguishable from wound pain was described by 17 patients (50.0%). The most common descriptions were of 'bloating' (41.2%), 'pins and needles' (35.3%), or 'numbness' (23.5%) in the chest wall. The Paresthesia resolved in less than two months in 12 patients (70.6%), but was still felt for over 12 months in three patients (17.6%). Post-operative Paresthesia and pain did not impact on patient satisfaction with the surgery, whereas compensatory hyperhidrosis in 24 patients (70.6%) did (P=0.001). The rates and characteristics of the Paresthesia following needlescopic VATS are similar to those observed after conventional VATS. Conclusions: Chest wall Paresthesia affects a significant but previously overlooked proportion of patients following needlescopic VATS, but has minimal impact on post-operative satisfaction. Needlescopic VATS offers no apparent advantage over conventional VATS with regard to Paresthesia.
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incidence of chest wall Paresthesia after video assisted thoracic surgery for primary spontaneous pneumothorax
European Journal of Cardio-Thoracic Surgery, 2004Co-Authors: Alan D L Sihoe, Sylvia S W Au, Mabel L Cheung, Ivan K L ChowAbstract:OBJECTIVE: Video-assisted thoracic surgery (VATS) is an established treatment for recurrent or complicated primary spontaneous pneumothorax (PSP). However, a proportion of patients still complains of chronic pain or discomfort after VATS pleurodesis. We aimed to investigate if Paresthesia is a distinct component of the post-operative discomfort in patients receiving VATS for PSP. METHODS: Telephone interviews were conducted with 52 patients who had received VATS pleurodesis for PSP in our institute during a defined 24 month period. A standardized questionnaire was used to identify paresthetic discomforts which the patients themselves could distinguish from their wound pain. Responses were obtained from 51 patients (42 male, 9 female) with a mean age of 24.1 years (range 14-63 years), giving a response rate of 98.0%. RESULTS: With a median observation time of 19 months (range 2-24 months), 27 patients (52.9%) reported experiencing Paresthesia as a post-operative complication distinct from their wound pain. The most commonly described characteristics of the Paresthesia were 'pins and needles' (37.0%), 'numbness' (25.9%) or a sensation of abnormal 'swelling' in the chest wall (11.1%). Although only two of the affected patients (7.4%) described the Paresthesia as 'severe', consequent functional disturbances in daily life were noted by seven patients (25.9%), and 11 patients (40.7%) actively sought medical or alternative, holistic therapies to relieve the Paresthesia. Eight (21.0%) of the 38 patients followed-up for over 12 months after surgery still experienced the Paresthesia. CONCLUSIONS: Although it should not detract from the proven advantages of VATS, Paresthesia in the chest wall represents a distinct but previously overlooked post-VATS complication. It is a potential source of significant post-operative morbidity, and may run a chronic course in some patients. Further study is warranted to elucidate its mechanisms and optimum management.
