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Tsuneharu Miki - One of the best experts on this subject based on the ideXlab platform.
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Histologic and electrophysiological study of nerve regeneration using a polyglycolic acid-collagen nerve conduit filled with collagen sponge in canine model.
Urology, 2009Co-Authors: Kei Suzuki, Akihiro Kawauchi, Tatsuo Nakamura, Shin-ichi Itoi, Tadao Ito, Osamu Ukimura, Akeo Hagiwara, Hisakazu Yamagishi, Tsuneharu MikiAbstract:OBJECTIVES To determine the rate of achieving electrophysiologically proved functional recovery by autonomic nerve regeneration, with the aid of an artificial nerve conduit. METHODS A polyglycolic acid (PGA) collagen nerve conduit filled with collagen sponge was interposed in a 10-mm-long gap of the right hypogastric nerve (HGN) in 16 dogs. Histologic evaluation of nerve regeneration and electrophysiological analysis at 2 weeks and 2, 3, 4, 5, 6, 7, and 8 months (n = 2, each) after surgery was performed, measuring the responses for the spermatic ducts (SD), bladder neck (BN), and prostate contraction, by stimulating the right Lumbar Splanchnic Nerves (LSNs) from L2 to L4, after transection of the left HGN to eliminate substitutive pathways. RESULTS Two months after implantation, the regenerated neurofilaments were successfully extended through the graft from the proximal-to-distal direction. In 2 control dogs, electrostimulation of the right LSNs induced elevation of the intraluminal pressure of the SD, elevation of the BN pressure, and prostate contraction. No responses were observed in all dogs up to 6 months of follow-up after implantation. In 1 dog with a 7-month follow-up, electrostimulation elicited elevation of BN pressure alone. In both dogs with an 8-month follow-up, electrostimulation induced similar responses to control in all SD, BN, and prostate; however, after excision of the area of the interposed right HGN, no response was observed. CONCLUSIONS These results proved that regeneration of a 10-mm gap of the HGN, using a novel PGA-collagen nerve conduit could be achieved within 8 months.
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post chemotherapy nerve sparing retroperitoneal lymph node dissection for advanced germ cell tumor
International Journal of Urology, 2009Co-Authors: Tsuneharu Miki, Yoichi Mizutani, Terukazu Nakamura, Akihiro Kawauchi, Akira Nagahara, Norio Nonomura, Akihiko OkuyamaAbstract:Objective: To report our experience with post-chemotherapy nerve-sparing retroperitoneal lymph node dissection (RPLND) for advanced germ cell tumor (GCT). Methods: Between 1994 and 2008, 92 patients with advanced GCT underwent RPLND after multiple treatments with systemic chemotherapy at our institution. A nerve-sparing RPLND was carried out in 78 patients (84.8%; median age 32 years). Of them, 19 had a seminoma and 59 had a non-seminoma. Results: Lumbar Splanchnic Nerves controlling ejaculatory function were macroscopically preserved during RPLND. Bilateral and unilateral Lumbar Splanchnic Nerves were preserved in 40 patients and 38 patients, respectively. Sixty-five patients could be evaluated for ejaculation. Fifty-four patients (83.1%) achieved antegrade ejaculation with a median postoperative interval of 3 months (range: 1–10 months). Twenty-eight patients (28/30: 93.3%) and 26 patients (26/35: 74.3%) undergoing bilateral and unilateral nerve-sparing RPLND had antegrade ejaculation, respectively (P = 0.041). Only two patients (2.6%) had mediastinal and retroperitoneal recurrences during a median follow-up of 42 months (range: 1–138 months), respectively. However, these patients were cured by chemotherapy and surgery. Conclusions: Post-chemotherapy nerve-sparing RPLND preserves ejaculatory function in the majority of patients with advanced GCT without increasing the risk of local recurrence.
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Nerve-sparing retroperitoneal lymph node dissection for advanced testicular cancer after chemotherapy.
International journal of urology : official journal of the Japanese Urological Association, 2002Co-Authors: Norio Nonomura, Akihiko Okuyama, Kazuo Nishimura, Natsuki Takaha, Hitoshi Inoue, Takeshi Nomoto, Youichi Mizutani, Masahiro Nakao, Tsuneharu MikiAbstract:Background: Nerve-sparing techniques are commonly used in retroperitoneal lymph node dissection (RPLND) in patients with early stage testicular germ cell tumors to preserve postoperative ejaculation. The indications for nerve-sparing procedures have been extended to patients who have residual retroperitoneal tumor postchemotherapy with an increase in the incidence of local recurrence. Here, we report on 26 Japanese men with advanced testicular cancer who underwent nerve-sparing RPLND after partially successful chemotherapy. Methods: Between January 1995 and December 2000, 26 patients with metastatic or recurrent testicular cancer underwent nerve-sparing RPLND after chemotherapy. Eight patients had seminoma and 18 had non-seminoma. Three patients received high-dose chemotherapy with carboplatin (250 mg/m2 per day × 5 days), etoposide (300 mg/m2 per day × 5 days) and ifosfamide (1.5 g/m2 per day × 5 days) in combination with peripheral blood stem cell transplantation. Results: In all cases, Lumbar Splanchnic Nerves were preserved macroscopically during the operation, at least unilaterally. Twenty-two patients (84.6%) achieved antegrade ejaculation during a mean follow-up at 3.9 months (range: 1–7 months). Three patients have fathered children. Only one patient suffered a retroperitoneal recurrence during a median follow-up at 25.8 months (range: 6–76 months). Conclusion: Nerve-sparing procedures for RPLND are appropriate for patients with metastatic testicular cancer, even after chemotherapy. The procedure preserves ejaculatory function in the majority of the patients without increasing the risk of local recurrence. Nerve-sparing RPLND improves the quality of life in patients who require postchemotherapy RPLND to treat residual tumor.
Brian L. Allman - One of the best experts on this subject based on the ideXlab platform.
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The anatomy of the infrarenal Lumbar Splanchnic Nerves in human cadavers: implications for retroperitoneal nerve‐sparing surgery
Journal of anatomy, 2017Co-Authors: Tyler S. Beveridge, Dale E. Fournier, Adam M.r. Groh, Marjorie Johnson, Nicholas Power, Brian L. AllmanAbstract:Injury to the Nerves of the aortic- and superior hypogastric plexuses during retroperitoneal surgery often results in significant post-operative complications, including retrograde ejaculation and/or loss of seminal emission in males. Although previous characterizations of these plexuses have done well to provide a basis for understanding the typical anatomy, additional research into the common variations of these plexuses could further optimize nerve-sparing techniques for retroperitoneal surgery. To achieve this, the present study aimed to document the prevalence and positional variability of the infrarenal Lumbar Splanchnic Nerves (LSNs) through gross dissection of 26 human cadavers. In almost all cases, two LSNs were observed joining each side of the aortic plexus, with 48% (left) and 33% (right) of specimens also exhibiting a third joining inferior to the left renal vein. As expected, the position of the LSNs varied greatly between specimens. That said, the vast majority (98%) of LSNs joining the aortic plexus were found to originate from the Lumbar sympathetic trunk above the level of the inferior mesenteric artery. It was also found that, within specimens, adjacent LSNs often coursed in parallel. In addition to these Nerves, 85% of specimens also demonstrated retroaortic LSN(s) that were angled more inferior compared with the other LSNs (P
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Anatomy of the Nerves and ganglia of the aortic plexus in males.
Journal of anatomy, 2014Co-Authors: Tyler S. Beveridge, Marjorie Johnson, Nicholas Power, Adam H. Power, Brian L. AllmanAbstract:It is well accepted that the aortic plexus is a network of pre- and post-ganglionic Nerves overlying the abdominal aorta, which is primarily involved with the sympathetic innervation to the mesenteric, pelvic and urogenital organs. Because a comprehensive anatomical description of the aortic plexus and its connections with adjacent plexuses are lacking, these delicate structures are prone to unintended damage during abdominal surgeries. Through dissection of fresh, frozen human cadavers (n = 7), the present study aimed to provide the first complete mapping of the Nerves and ganglia of the aortic plexus in males. Using standard histochemical procedures, ganglia of the aortic plexus were verified through microscopic analysis using haematoxylin & eosin (H&E) and anti-tyrosine hydroxylase stains. All specimens exhibited four distinct sympathetic ganglia within the aortic plexus: the right and left spermatic ganglia, the inferior mesenteric ganglion and one previously unidentified ganglion, which has been named the prehypogastric ganglion by the authors. The spermatic ganglia were consistently supplied by the L1 Lumbar Splanchnic Nerves and the inferior mesenteric ganglion and the newly characterized prehypogastric ganglion were supplied by the left and right L2 Lumbar Splanchnic Nerves, respectively. Additionally, our examination revealed the aortic plexus does have potential for variation, primarily in the possibility of exhibiting accessory Splanchnic Nerves. Clinically, our results could have significant implications for preserving fertility in men as well as sympathetic function to the hindgut and pelvis during retroperitoneal surgeries.
Kazunori Kihara - One of the best experts on this subject based on the ideXlab platform.
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Reconstruction of the sympathetic pathway projecting to the prostate, by nerve grafting in the dog.
BJU international, 2004Co-Authors: Nobuhiko Hyochi, Kazunori Kihara, Gaku Arai, Tsuyoshi Kobayashi, Kenji SatoAbstract:OBJECTIVES To examine the possibility of nerve grafting to repair the sympathetic pathway projecting to the prostate, as contraction of the prostate is known to be controlled by the sympathetic pathway via the hypogastric nerve (HGN), and injuries to the pathway cause significant disturbances in prostatic secretion. MATERIALS AND METHODS In six dogs both of the HGNs were partly removed and immediately repaired with an autologous nerve graft. The left HGN was repaired with a colonic (autonomic) nerve graft and the right with a genitofemoral (somatic) nerve graft. Twenty months after surgery the reconstruction of the sympathetic pathway was assessed by measuring contraction of the prostate after stimulating the Lumbar Splanchnic Nerves (LSNs). RESULTS Nine of the 17 right LSNs stimulated elicited prostatic contractions. After transecting the left HGN five of these nine responses were restored. Seven of the 11 left LSNs stimulated elicited prostatic contractions; after transection of the left HGN four of these seven responses were preserved. CONCLUSION The sympathetic pathways via the HGN to the canine prostate can be reconstructed by nerve grafting, regardless of the use of autonomic or somatic nerve grafts, and the cross-innervation mechanism from the LSN to the prostate can also be repaired.
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SPINAL CORD SEGMENTS CONTROLLING THE CANINE VAS DEFERENS AND DIFFERENTIATION OF THE PRIMATE SYMPATHETIC PATHWAYS TO THE VAS DEFERENS
Microscopy Research and Technique, 1998Co-Authors: Kenji Sato, Kazunori KiharaAbstract:: This study was undertaken to explore the spinal cord segments controlling the canine and human vas deferens and differentiation of the mammalian sympathetic pathways to the vas deferens. ThoracoLumbar white communicating rami (WCR) were electrically stimulated in the dogs. Stimulation of the 1st, 2nd, 3rd, and 4th Lumbar WCR elicited an elevation of intraluminal pressure of the vas deferens in 2, 10, 16, and 14 of 20 dogs examined, respectively, whereas stimulation of sympathetic chain (between the 13th thoracic and 1st Lumbar ganglia), 13th thoracic WCR, intermesenteric plexus, and 5th Lumbar WCR showed no response in any of the 10, 2, 12, and 5 dogs examined, respectively. Anatomical study of the 118 human Lumbar Splanchnic Nerves of 55 cadavers showed that almost all Lumbar Splanchnic Nerves (96%) originated from L2 and/or L3 sympathetic chain ganglia (L1-2 spinal cord levels). Comparative anatomical study of the mammalian sympathetic pathways to the vas deferens showed that the caudal mesenteric plexus is not divided in rats, rabbits, cats, and dogs and is partially divided into two plexuses in monkeys and completely in humans and that separation of the sympathetic component in the pelvic nerve (isolation of the sacral Splanchnic nerve) is in progress in the primate. These results indicate that spinal cord segments controlling the vas deferens are L1-4 in the dog and probably L1-2 in humans and that differentiation of the sympathetic nerve pathways is proceeding at both main and compensatory pathways to the vas deferens in the primate.
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Sympathetic efferent pathways projecting bilaterally to the vas deferens in the rat.
The Anatomical record, 1997Co-Authors: Kazunori Kihara, William C. De GroatAbstract:ABSTRACT Background: The laterality of the signals passing through the Splanchnic Nerves to the vas deferens has not been well studied. Methods: The present study was designed to determine the bilateral distribution of sympathetic Nerves to the rat vasa deferentia by measuring intravasal pressure (VP) responses to electrical stimulation of left Lumbar Splanchnic Nerves (LSN) following consecutive transections of more distal Nerves. Results: L2-L6 LSN stimulation increased VP bilaterally. Left VP responses decreased slightly ( 80% after section of left HGN, not changed further by subsequent section of commissural branches (CB-MPG) between the MPG, and completely eliminated by section of commissural branches between the APG (CB-APG). Right VP responses were decreased slightly ( 70% by section of right HGN, not changed by section of CB-MPG, but then completely eliminated by section of CB-APG. Conclusions: These results indicate that the left Lumbar sympathetic pathway to the vas deferens is distributed bilaterally and exhibits two crossing points at the level of the inferior mesenteric ganglion and APG. Anat. Rec. 248:291-299, 1997. © 1997 Wiley-Liss, Inc.
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Regulation of the bladder neck closure by Lumbar Splanchnic Nerves at ejaculation in the dog
Neurourology and urodynamics, 1993Co-Authors: Masao Ando, Kazunori Kihara, Kenji Sato, Tatsuo Sato, Hiroyuki OshimaAbstract:To clarify the role of canine thoracoLumbar Splanchnic Nerves for bladder neck closure during ejaculation, these Nerves of adult male mongrel dogs were exposed under anesthesia using ketamine hydrochloride and pentobarbital, and electrical stimulation and anatomical dissection studies were performed. Bladder neck closure by the stimulation of each sympathetic nerve was monitored with a 10 Fr silicon catheter equipped with pressure-sensitive rubber balloon placed at the bladder neck. The dissection study revealed that canine thoracoLumbar Splanchnic Nerves consisted of two nerve groups: one branching from the sympathetic trunks at thoracic and L1 ganglia, reaching caudal mesenteric plexus (CMP) through the anterior wall of the aorta, the other branching from the sympathetic trunks at level L2-L5 ganglia, reaching CMP through the posterior side of the bilateral spermatic arteries. The former were designated intermesenteric Splanchnic Nerves, the latter Lumbar Splanchnic Nerves. No bladder neck closure was observed by electrical stimulation of the distal end of severed intermesenteric Splanchnic Nerves or of the sympathetic trunks at the lumbopelvic level among 10 dogs examined. At least one Lumbar Splanchnic nerve generated the closure in all 10 dogs and generally, a few Lumbar Splanchnic Nerves, generated the closure. The results indicate that bladder neck closure during ejaculation is generated by Lumbar Splanchnic Nerves regardless of their branching levels from Lumbar sympathetic ganglia, but not by either intermesenteric Splanchnic Nerves or pelvic sympathetic trunks.
Tyler S. Beveridge - One of the best experts on this subject based on the ideXlab platform.
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The anatomy of the infrarenal Lumbar Splanchnic Nerves in human cadavers: implications for retroperitoneal nerve‐sparing surgery
Journal of anatomy, 2017Co-Authors: Tyler S. Beveridge, Dale E. Fournier, Adam M.r. Groh, Marjorie Johnson, Nicholas Power, Brian L. AllmanAbstract:Injury to the Nerves of the aortic- and superior hypogastric plexuses during retroperitoneal surgery often results in significant post-operative complications, including retrograde ejaculation and/or loss of seminal emission in males. Although previous characterizations of these plexuses have done well to provide a basis for understanding the typical anatomy, additional research into the common variations of these plexuses could further optimize nerve-sparing techniques for retroperitoneal surgery. To achieve this, the present study aimed to document the prevalence and positional variability of the infrarenal Lumbar Splanchnic Nerves (LSNs) through gross dissection of 26 human cadavers. In almost all cases, two LSNs were observed joining each side of the aortic plexus, with 48% (left) and 33% (right) of specimens also exhibiting a third joining inferior to the left renal vein. As expected, the position of the LSNs varied greatly between specimens. That said, the vast majority (98%) of LSNs joining the aortic plexus were found to originate from the Lumbar sympathetic trunk above the level of the inferior mesenteric artery. It was also found that, within specimens, adjacent LSNs often coursed in parallel. In addition to these Nerves, 85% of specimens also demonstrated retroaortic LSN(s) that were angled more inferior compared with the other LSNs (P
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Anatomy of the Nerves and ganglia of the aortic plexus in males.
Journal of anatomy, 2014Co-Authors: Tyler S. Beveridge, Marjorie Johnson, Nicholas Power, Adam H. Power, Brian L. AllmanAbstract:It is well accepted that the aortic plexus is a network of pre- and post-ganglionic Nerves overlying the abdominal aorta, which is primarily involved with the sympathetic innervation to the mesenteric, pelvic and urogenital organs. Because a comprehensive anatomical description of the aortic plexus and its connections with adjacent plexuses are lacking, these delicate structures are prone to unintended damage during abdominal surgeries. Through dissection of fresh, frozen human cadavers (n = 7), the present study aimed to provide the first complete mapping of the Nerves and ganglia of the aortic plexus in males. Using standard histochemical procedures, ganglia of the aortic plexus were verified through microscopic analysis using haematoxylin & eosin (H&E) and anti-tyrosine hydroxylase stains. All specimens exhibited four distinct sympathetic ganglia within the aortic plexus: the right and left spermatic ganglia, the inferior mesenteric ganglion and one previously unidentified ganglion, which has been named the prehypogastric ganglion by the authors. The spermatic ganglia were consistently supplied by the L1 Lumbar Splanchnic Nerves and the inferior mesenteric ganglion and the newly characterized prehypogastric ganglion were supplied by the left and right L2 Lumbar Splanchnic Nerves, respectively. Additionally, our examination revealed the aortic plexus does have potential for variation, primarily in the possibility of exhibiting accessory Splanchnic Nerves. Clinically, our results could have significant implications for preserving fertility in men as well as sympathetic function to the hindgut and pelvis during retroperitoneal surgeries.
Akihiko Okuyama - One of the best experts on this subject based on the ideXlab platform.
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post chemotherapy nerve sparing retroperitoneal lymph node dissection for advanced germ cell tumor
International Journal of Urology, 2009Co-Authors: Tsuneharu Miki, Yoichi Mizutani, Terukazu Nakamura, Akihiro Kawauchi, Akira Nagahara, Norio Nonomura, Akihiko OkuyamaAbstract:Objective: To report our experience with post-chemotherapy nerve-sparing retroperitoneal lymph node dissection (RPLND) for advanced germ cell tumor (GCT). Methods: Between 1994 and 2008, 92 patients with advanced GCT underwent RPLND after multiple treatments with systemic chemotherapy at our institution. A nerve-sparing RPLND was carried out in 78 patients (84.8%; median age 32 years). Of them, 19 had a seminoma and 59 had a non-seminoma. Results: Lumbar Splanchnic Nerves controlling ejaculatory function were macroscopically preserved during RPLND. Bilateral and unilateral Lumbar Splanchnic Nerves were preserved in 40 patients and 38 patients, respectively. Sixty-five patients could be evaluated for ejaculation. Fifty-four patients (83.1%) achieved antegrade ejaculation with a median postoperative interval of 3 months (range: 1–10 months). Twenty-eight patients (28/30: 93.3%) and 26 patients (26/35: 74.3%) undergoing bilateral and unilateral nerve-sparing RPLND had antegrade ejaculation, respectively (P = 0.041). Only two patients (2.6%) had mediastinal and retroperitoneal recurrences during a median follow-up of 42 months (range: 1–138 months), respectively. However, these patients were cured by chemotherapy and surgery. Conclusions: Post-chemotherapy nerve-sparing RPLND preserves ejaculatory function in the majority of patients with advanced GCT without increasing the risk of local recurrence.
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Nerve-sparing retroperitoneal lymph node dissection for advanced testicular cancer after chemotherapy.
International journal of urology : official journal of the Japanese Urological Association, 2002Co-Authors: Norio Nonomura, Akihiko Okuyama, Kazuo Nishimura, Natsuki Takaha, Hitoshi Inoue, Takeshi Nomoto, Youichi Mizutani, Masahiro Nakao, Tsuneharu MikiAbstract:Background: Nerve-sparing techniques are commonly used in retroperitoneal lymph node dissection (RPLND) in patients with early stage testicular germ cell tumors to preserve postoperative ejaculation. The indications for nerve-sparing procedures have been extended to patients who have residual retroperitoneal tumor postchemotherapy with an increase in the incidence of local recurrence. Here, we report on 26 Japanese men with advanced testicular cancer who underwent nerve-sparing RPLND after partially successful chemotherapy. Methods: Between January 1995 and December 2000, 26 patients with metastatic or recurrent testicular cancer underwent nerve-sparing RPLND after chemotherapy. Eight patients had seminoma and 18 had non-seminoma. Three patients received high-dose chemotherapy with carboplatin (250 mg/m2 per day × 5 days), etoposide (300 mg/m2 per day × 5 days) and ifosfamide (1.5 g/m2 per day × 5 days) in combination with peripheral blood stem cell transplantation. Results: In all cases, Lumbar Splanchnic Nerves were preserved macroscopically during the operation, at least unilaterally. Twenty-two patients (84.6%) achieved antegrade ejaculation during a mean follow-up at 3.9 months (range: 1–7 months). Three patients have fathered children. Only one patient suffered a retroperitoneal recurrence during a median follow-up at 25.8 months (range: 6–76 months). Conclusion: Nerve-sparing procedures for RPLND are appropriate for patients with metastatic testicular cancer, even after chemotherapy. The procedure preserves ejaculatory function in the majority of the patients without increasing the risk of local recurrence. Nerve-sparing RPLND improves the quality of life in patients who require postchemotherapy RPLND to treat residual tumor.
