Fingertip coverage with uni-pedicled volar rotational advancement flap with large Z-plasty: a report on 112 cases

BACKGROUND

Simple and safe fingertip reconstruction methods involve the use of local neurovascular islands flaps that can preserve functional length and sensitivity, and reconstruction with skin of the same texture. However, techniques involving flaps have numerous drawbacks and do not satisfy all the requirements for fingertip reconstruction. A particular problem is the persistence of contracture deformity due to lack of full flap advancement. We present a new technique using uni-pedicled volar rotational advancement flap with large Z-plasty, and describe the results of long-term follow-up.

METHODS

From October 1993 to December 2009, 112 fingers of 98 patients were covered with uni-pedicled volar rotational advancement flap with large Z-plasty after sustaining various types of injuries or finger pulp avulsion. A longitudinal incision was made along the lateral border of the digit and a large neurovascular volar flap was elevated just above the pulleys and flexor tendon sheath. To release tension, a large Z-plasty was applied at the metacarpophalangeal joint or interphalangeal joint crease. The final patient outcomes were reviewed retrospectively.

RESULTS

All fingertip injuries were treated without flap necrosis. Partial wound dehiscence was observed in two patients and average static two-point discrimination was 5.2 mm. There were no postoperative contracture deformities, joint stiffness, paresthesia, or hypersensitivity. Most patients were left with acceptable scarring and were free of postoperative pain and cold intolerance during the long-term follow-up.

CONCLUSIONS

Our novel technique provides durable, completely sensate, and well-vascularized coverage of the fingertip with minimal discomfort to patients.

Nerve Protection During Prostate Cryosurgery

Cryosurgery is a minimally invasive approach to the treatment of focal prostate cancer (PCa). A major complication is the cryoinjury to the cavernous nerve in the neurovascular bundle (NVB). This nerve cryoinjury halts conduction of action potentials (APs) and can eventually result in erectile dysfunction and therefore diminished quality of life for the patient. Here, we propose the application of cryoprotective agents (CPA) to the regions of the nerves in the NVB, prior to prostate cryosurgery, to minimize non-recoverable loss of AP conduction. We modeled a cryosurgical procedure based on data taken during a clinical case and applied ex-vivo porcine phrenic nerves and rat sciatic nerve with temperature profile of NVB. The APs were measured before and after the CPA exposures and during 3 h of recovery. Comparisons of AP amplitude recovery with various CPA compositions reveal that certain CPAs (e.g., 5% DMSO + 7.5% Trehalose and 5% M22 for porcine and rat nerves, respectively) showed little or no toxicity and effective cryoprotection from freezing (on average 48% and 30% of recovered AP, respectively). In summary, we demonstrate that neural conduction can be preserved after exposure to freezing conditions if CPAs are properly selected and deployed onto the nerve.

The application of indocyanine green in guiding prostate cancer treatment

Objective

Indocyanine green (ICG) with near-infrared fluorescence absorption is approved by the United States Food and Drug Administration for clinical applications in angiography, blood flow evaluation, and liver function assessment. It has strong optical absorption in the near-infrared region, where light can penetrate deepest into biological tissue. We sought to review its value in guiding prostate cancer treatment.

Methods

All related literature at PubMed from January 2000 to December 2020 were reviewed.

Results

Multiple preclinical studies have demonstrated the usefulness of ICG in identifying prostate cancer by using different engineering techniques. Clinical studies have demonstrated the usefulness of ICG in guiding sentinel node dissection during radical prostatectomy, and possible better preservation of neurovascular bundle by identifying landmark prostatic arteries. New techniques such as adding fluorescein in additional to ICG were tested in a limited number of patients with encouraging result. In addition, the use of the ICG was shown to be safe. Even though there are encouraging results, it does not carry sufficient sensitivity and specificity in replacing extended pelvic lymph node dissection during radical prostatectomy.

Conclusion

Multiple preclinical and clinical studies have shown the usefulness of ICG in identifying and guiding treatment for prostate cancer. Larger randomized prospective studies are warranted to further test its usefulness and find new modified approaches.

[Anatomical observation and clinical significance of the prostatic part of neurovascular bundle in total mesorectal excision]

Objective: To observe the anatomical architecture of the prostatic part of the neurovascular bundle (NVB) in total mesorectal excision (TME). Methods: A descriptive cohort study and an anatomical observation study were carried out. A total of 38 male patients with rectal cancer who underwent TME in the Department of Colorectal Surgery at the affiliated Union hospital of Fujian Medical University between November 2013 and March 2015 were included. A total of 4 hemipelvis were examined at the Laboratory of Clinical Applied Anatomy, Fujian Medical University. The following outcomes were observed: 1) the clinical significance of bleeding of the prostatic part of NVB: surgical videos were reviewed and the incidence of bleeding was recorded. The urogenital function was assessed using the International Prostate Symptom Score (IPSS) and International Index of Erectile Function (IIEF) score. The correlation between prostatic part bleeding and postoperative urogenital function was evaluated. 2) anatomical observation: the vessels, nerve fibers, as well as their surrounding fatty tissue from the prostatic part were treated as a whole, namely, the fat pad of the prostatic part. The anatomical architecture of the prostatic part in the surgical videos was reviewed and interpreted with the cadaveric findings. Categorical variables were compared between groups using a Fisher exact probability. while continuous variables with skewed distribution were compared between groups using the Mann-Whiteny U test. Results: The median age of the included 38 patients was 57 years (range, 31-75), and the median tumor distance to the anal verge was 6 cm (range, 1-8). Of them, a total number of 21 (55.3%) patients had bleeding of the prostatic part of NVB (bleeding group), while the rest had not (17 cases, 44.7%, non-bleeding group). 1) the clinical significance of bleeding of the prostatic part of NVB. The urinary function significantly decreased in patients in the bleeding group according to IPSS score after the 3rd month and the 6rd month of the surgery [7 (0-16) vs. 2 (0-3), Z=-1.787, P=0.088; 2 (0-15) vs. 0 (0-2), Z=-2.270, P=0.028]. There was no difference regarding the IPSS score between the two groups after 1 year of the surgery (P>0.05). With a total of 23 patients with normal preoperative sexual activity included, 87.5% (7/8) of patients in the non-bleeding group can expect to return to their preoperative baseline, this incidence was significantly higher than that of only 40% (6/15) in the bleeding group (P=0.029). 2) anatomical observation: for cadaveric observation, the prostatic part of NVB was located in the narrow triangular space composed of anterolateral walls of the rectum, the posterolateral surface of the prostate and the medial surface of the levator ani musculature. The tiny vascular branches and nerve fibers from the prostatic part were hard to identify. The cavernosal nerves cannot reliably be distinguished from the neural supply to the prostate, rectum and levator ani. In the cross-section of levels of prostatic base and mid-prostate in cadaveric hemipelvis specimens, the boundary of the prostatic part fat pad was partly overlapped and merged with the boundary of the mesorectum. Intraoperative observation showed that the areas of overlap referred to the rectal branches from the prostatic part piercing the proper fascia to supply the mesorectum, which carried the largest tension and high risk of bleeding during circumferential dissection toward the perirectal plane. The ultrasonic scalpel was required to pre-coagulate the rectal branches at the point close to the proper fascia of the rectum to prevent bleeding. In the cross-section of the prostatic apex level, the prostatic part approached ventrally and its boundary was away from the boundary of the mesorectum. Conclusions: NVB prostatic part injury is one of the causes of urogenital dysfunction after TME. The nerve fibers from the prostatic part were tiny, and its functional zones cannot be distinguished during operation. Therein, the fat pad of the prostatic part should be protected as a whole. Understanding the morphology of the fat pad of the prostatic part provides invaluable surgical guidance to dissect this critical area. When dissecting around the anterolateral rectal wall, appropriate anti-traction tension should be maintained and the rectal branches from the prostatic part should be coagulated with an ultrasonic scalpel to prevent bleeding.

Does the adherence of distal femur parosteal osteosarcoma to the neurovascular bundle increase the rate of local recurrences?

BACKGROUND

Proximity of tumor to the neurovascular bundle (NVB) makes achieving a wide margin difficult. In low-grade parosteal osteosarcoma (POS), it is not clear whether adherence of tumor to NVB increases the rate of local recurrence (LR). In this study, we evaluated whether tumor adherence to the NVB increases the risk of LR in low-grade POS of the distal femur?

HYPOTHESIS

We hypothesized that if the thin neurovascular barrier (the adventitia of the vessels and the epineurium of the nerve) prevents tumor penetration, the rate of LR should be comparable between the lesions with and without a continuous layer of healthy fatty tissue between the tumor and NVB.

MATERIALS AND METHODS

In a retrospective survey, 30 patients with low-grade POS of the posterior aspect of the distal femur were evaluated for the proximity of mass to NVB. Based on the proximal to distal T1 axial MRI sections, the tumors were divided into two groups including the tumors with an uninterrupted (group A) and interrupted (group B) rim of fatty tissue between the mass and NVB. The rate of LR was compared between the two study groups. The concordance of MRI in detecting NVB adherence was checked with pathology specimen.

RESULTS

Using MRI, we identified 16 cases in group A and 14 cases in group B. The MRI status of fatty rim was concordant with pathology specimen in 96.4% of cases. The mean follow-up period of the two groups was not statistically different (117±27.6 vs. 105.8±29.4 months, respectively, p=0.29). The other baseline characteristics of the two groups were statistically comparable, as well. The rate of LR was 12.5% (2 out of 16 patients) in group A and 14.3% (2 out of 14 patients) in group B (95% CI: 0.142-9.586, p=0.87). The 10-year recurrence-free survival was 87.5% for group A and 85.7% for group B (p=0.9).

DISCUSSION

The absence of a continuous rim of fatty tissue between the tumor and NVB in MRI does not increase the risk of LR in low-grade POS of the distal femur.

LEVEL OF EVIDENCE

IV.

Gli1+ Mesenchymal Stem Cells in Bone and Teeth

Mesenchymal stem cells (MSCs) are remarkable and noteworthy. Identification of markers for MSCs enables the study of their niche in vivo. It has been identified that glioma-associated oncogene 1 positive (Gli1+) cells are mesenchymal stem cells supporting homeostasis and injury repair, especially in the skeletal system and teeth. This review outlines the role of Gli1+ cells as an MSC subpopulation in both bones and teeth, suggesting the prospects of Gli1+ cells in stem cell-based tissue engineering.

Preserving the vitality of teeth adjacent to a large radicular cyst in periapical microsurgery: a case report with 4-year follow-up

Background

Radicular cysts may enlarge considerably, cause extensive bone destruction, and jeopardize the integrity of the associated vital teeth. The different treatment approaches are aimed mainly at eliminating the cystic epithelial membrane while reducing the risk of injury to vital structures. Contrary to other treatment modalities, preapical surgery offers an unequivocal single occasion resolution for the patient. However, it has been associated with higher risk of collateral damages.

Case presentation

A patient presented with a large radicular cyst originating from a maxillary lateral incisor. The adjacent central and canine teeth initially failed to exhibit responses to sensibility tests but showed signs of vitality. Microsurgical management was aimed at enucleating the cystic membrane while maintaining adjacent teeth vitality. Upon careful and controlled cyst enucleation under the dental operating microscope, the neurovascular bundle of one of the involved teeth was visualized and its integrity was maintained throughout the procedure.

Results

The procedure was successful and follow up recalls revealed recovery of normal sensibility of tooth 11 and 13 with complete bone regeneration around their apices.

Conclusion

Within the limitation of the present case report, we demonstrated that complete excision of large periapical cyst can be performed without sacrificing the vitality of the adjacent teeth, by preserving the integrity of their neurovascular supply through controlled microsurgical enucleation, and by a potential apical vascular repair ensuing unintended injury. Diagnosing the pulp vitality of non-offending teeth whose apices protrude into the cystic lumen is a complex process and can be misleading. Pressure from the growing cyst can inhibit vital teeth responses to neural-based sensibility tests leading to false negative results. Thus, in such cases, the use of blood perfusion-based vitality testing is recommended for correct initial diagnosis.

Importance and implications of neurovascular bundle involvement and other MRI findings of oral tongue squamous cell carcinoma (OTSCC) on prognosis

BACKGROUND

The description for T4a oral tongue cancer in the 8th edition AJCC staging can be improved further. In this article we attempted to identify the important radiological (MRI) findings that could possibly be included in the staging eventually.

METHODS

We included all oral tongue squamous cell carcinoma patients who underwent surgery at TMH between Jan 2012 to Dec 2018 and whose MRIs were available for review. The relation of the tumor to the neurovascular bundle (NVB) on MRI was classified as Type I to IV. The association of the type of NVB involvement with DFS and the presence of PNI in the final HPR was analyzed.

RESULTS

Two-hundred and fifty-nine patients satisfied the eligibility criteria. The majority of them were men (82.6%), with a median age of 49 Yrs. Sixty-nine percent of patients had either abutment (Type III) or encasement (Type IV) of the NVB. The presence of Abutment/encasement of the NVB was significantly associated with the presence of PNI in the final HPR (p < 0.001). This abutment/encasement was seen in clinically advanced T-stage tumors. However, the presence of abutment/encasement of the NVB influenced the DFS in the univariate analysis only.

CONCLUSION

Abutment/encasement of the NVB in patients with carcinoma oral tongue is often seen in advanced-stage tumors and is significantly associated with the presence of PNI in the final HPR. Hence, the relation of the tumor with the NVB should be further assessed to understand its importance and its possible inclusion in the AJCC T-staging.

A calcaneal tunnel for CFL reconstruction should be directed to the posterior inferior medial edge of the calcaneal tuberosity

PURPOSE

Anatomical reconstruction of the calcaneofibular ligament (CFL) is a common technique to treat chronic lateral ankle instability. A bone tunnel is used to fix the graft in the calcaneus. The purpose of this study is to provide some recommendations about tunnel entrance and tunnel direction based on anatomical landmarks.

METHODS

The study consisted of two parts. The first part assessed the lateral tunnel entrance for location and safety. The second part addressed the tunnel direction and safety upon exiting the calcaneum on the medial side. In the first part, 29 specimens were used to locate the anatomical insertion of the CFL based on the intersection of two lines related to the fibular axis and specific landmarks on the lateral malleolus. In the second part, 22 specimens were dissected to determine the position of the neurovascular structures at risk during tunnel drilling. Therefore, a method based on four imaginary squares using external anatomical landmarks was developed.

RESULTS

For the tunnel entrance on the lateral side, the mean distance to the centre of the CFL footprint was 2.8 ± 3.0 mm (0-10.4 mm). The mean distance between both observers was 4.2 ± 3.2 mm (0-10.3 mm). The mean distance to the sural nerve was 1.4 ± 2 mm (0-5.8 mm). The mean distance to the peroneal tendons was 7.3 ± 3.1 mm (1.2-12.4 mm). For the tunnel exit on the medial side, the two anterior squares always contained the neurovascular bundle. A safe zone without important neurovascular structures was found and corresponded to the two posterior squares.

CONCLUSION

Lateral landmarks enabled to locate the CFL footprint. Precautions should be taken to protect the nearby sural nerve. A safe zone on the medial side could be determined to guide safe tunnel direction. A calcaneal tunnel should be directed to the posterior inferior medial edge of the calcaneal tuberosity.

Evidence-based evolution of our robot-assisted laparoscopic prostatectomy (RALP) technique through 13,000 cases

Robot-assisted laparoscopic radical prostatectomy (RALP) has become the standard of surgical care in the USA and around the world. Over the past 18 years, we have performed 13,000 radical prostatectomies, and our surgical technique has evolved over time. We discuss this evolution and how it has helped us achieve optimal patient outcomes.

[Mechanism and anatomy recognition of neurovascular bundle injury from different perspectives of transabdominal and transanal approach]

The neurovascular bundle (NVB) starts at the lateral angle of the seminal vesicle (the initial part), passes posterolateral of the prostate gland (the main part), and ends at the cavernous body of the penis (the cavernous part). In low rectal surgery, different transabdominal and transanal perspectives result in different NVB injury risks. In the perspective of transabdominal operation, the separation between the initial part of NVB and Denonvilliers fascia and the anatomical variation of the two lateral sides of Denonvilliers fascia increases the risk of NVB injury, and conformation separation may take into account the convenience of separationand the protection of NVB. In the perspective of transanal operation, when separating the main part with NVB and mesorectum, the perspective of the transanal, unidirection traction and excessive dissection increase the risk of NVB main exposure. Clear anatomical identification helps the protection of NVB in the transanal operation. At present, the medical evidence on the difference of NVB injury in different perspectives of transabdominal and transanal approach is still in need of relevant clinical researches.

A single-center, retrospective review of robot-assisted laparoscopic prostatectomy with and without cryopreserved umbilical cord allograft in improving continence recovery

The objective of this study was to evaluate the safety and effectiveness of cryopreserved umbilical cord (UC) allograft as a nerve wrap around the neurovascular bundle (NVB) in accelerating return to continence after radical prostatectomy. A single-center, retrospective study was performed on 200 patients who underwent bilateral, nerve-sparing robot-assisted radical prostatectomy (RARP) with and without placement of UC around the NVBs (n = 100/group). Patients were excluded if they had previous simple or transurethral prostatectomy or history of pelvic radiation. Post-operative continence, defined as 0 or 1 safety pad, was analyzed between groups at 1, 3, 6, and 12 months. Complications, biochemical recurrence and adverse events were assessed to determine safety. Patients who underwent RARP with UC were significantly more likely to be continent at 1 month (65% vs. 44%, p = 0.018), 3 months (83% vs. 70%, p = 0.03), and 12 months (97% vs. 87%, p = 0.009). Sample stratification revealed that UC is beneficial for obese patients and those > 60 years, both of which are high risk for post-RARP incontinence. Biochemical failure was noted in 2 (UC) and 4 (control) patients. No adverse events or complications related to UC were observed. The results suggest that UC allograft is safe and accelerates continence recovery in post-RARP patients. Prospective, randomized trials are warranted.

Analysis of a practical surgical skills laboratory for nerve sparing radical prostatectomy

PURPOSE

With the rapidly expanding anatomical and technical knowledge surrounding nervesparing radical prostatectomy (NSRP), anatomical and operative textbooks have failed to keep pace with the literature. A surgical skill laboratory (SSL) was designed to educate urology trainees on surgical anatomy and techniques for NSRP. The objective was to assess the validity of a SSL program.

METHODS

A low-fidelity, anatomically accurate prostate model with its appropriate fascial coverings and location of the neurovascular bundle was created. Participants were surveyed prior to a SSL workshop for their knowledge of NSRP focusing on clinical and anatomical considerations. An interactive 2-h tutorial and workshop was then undertaken outlining the clinical and anatomical nuances for NSRP, with participants then practising an intra and inter-fascial NSRP on the model. Participants were resurveyed immediately after the workshop and at 6 months.

RESULTS

Thirty participants completed the NSRP workshop. Significant differences (p < 0.0001) in anatomical and clinical knowledge were noted after the workshop with improvements for both junior and senior trainees. The knowledge was retained at 6 months following the workshop.

CONCLUSIONS

A low-fidelity bench-top model is a feasible and reproducible technique for improving the understanding of periprostatic anatomy and the different surgical approaches for NSRP. The SSL is useful and knowledge gained appears to be retained by workshop participants. SSL workshops are a valid hands-on approach to teaching surgical skills and should remain an integral part of urology training.

Robot-assisted nerve-sparing radical prostatectomy using near-infrared fluorescence technology and indocyanine green: initial experience

INTRODUCTION

Indocyanine green (ICG) is a fluorescent molecule that provokes detectable photon emission. The use of ICG with near-infrared (NIR) imaging system (Akorn, Lake Forest, IL) has been described during robotic partial nephrectomy (RAPN) as an adjunctive means of identifying renal artery and parenchymal perfusion. We propose the use of the ICG with NIR fluorescence during laparoscopic robot-assisted radical prostatectomy (RARP), to identify the benchmark artery improving the preservation of neurovascular bundle and to improve the visualization of the vascularization and then the hemostasis.

METHODS

From April 2015 to February 2016, 62 patients underwent to RARP in our Urology Unit. In 26 consecutive patients, in the attempt to have a better visualization of neurovascular bundles, we used to inject ICG during the procedure. We evaluated the percentage of identification of neurovascular bundles using NIR fluorescence. Then, we evaluated complications related to injection of ICG and operative time differences between RARP with and without ICG injection performed by the same surgeons.

RESULTS

We identified prostatic arteries and neurovascular bundles using NIR fluorescence technology in all patients (100%). There was not any increase in the operative time compared with RARP without ICG injection performed by the same surgeons. Complications related to injection of ICG did not occurred.

CONCLUSIONS

In our experience, even if on a limited number of patients, the application of ICG with NIR fluorescence during RARP is helpful to identify the benchmark artery of neurovascular bundle.

Neurovascular bundle size measured on 3.0-T magnetic resonance imaging is associated with the recovery of erectile function after robot-assisted radical prostatectomy

BACKGROUND AND OBJECTIVE

Erectile dysfunction is one of the complications occurring after radical prostatectomy (RP), and recovery of erectile function is quantitatively related to the preservation of the neurovascular bundles (NVB).We evaluated the significance of NVB area on functional outcomes after RP.

MATERIALS AND METHODS

Preoperative magnetic resonance imaging was performed on 141 patients who underwent bilateral, nerve-sparing, robot-assisted RP for clinically localized prostate cancer (clinically T2N0M0 on magnetic resonance imaging) and were evaluated at least 12 months after surgery. NVB area was measured as a region of interest that coincided with the outline of the maximum area of the posterolateral region of the prostate on T2-weighted axial imaging. Factors associated with functional outcomes were evaluated using logistic regression analysis.

RESULTS

Of 141 patients, 36 patients (25.5%) had no preoperative potency (group 1), 66 patients (46.8%) recovered potency (group 2), and 39 patients (27.7%) did not recover potency (group 3). Although the mean age of the entire cohort was 65.4 years, the mean age of group 1 was greater than groups 2 and 3 (P = 0.001). The NVB area of group 2 was larger than those of groups 1 and 3 (P = 0.001). Potency evaluations involved 105 patients (74.5%; groups 2 and 3), and patients with pre-existing erectile dysfunction were excluded. The median time to potency recovery was 3.0 months after surgery. The multivariable analysis revealed that the NVB area was the only significant factor predictive of potency recovery.

CONCLUSIONS

The NVB area in the posterolateral region of the prostate is an independent factor for predicting potency recovery. The degree of postoperative erectile function can be predicted based on the preoperative NVB area.

A Critical Analysis of the Current Knowledge of Surgical Anatomy of the Prostate Related to Optimisation of Cancer Control and Preservation of Continence and Erection in Candidates for Radical Prostatectomy: An Update

CONTEXT

In 2010, we published a review summarising the available literature on surgical anatomy of the prostate and adjacent structures involved in cancer control and the functional outcome of prostatectomy.

OBJECTIVE

To provide an update based on new literature to help the surgeon improve oncologic and surgical outcomes of radical prostatectomy (RP).

EVIDENCE ACQUISITION

We searched the PubMed database using the keywords radical prostatectomy, anatomy, neurovascular bundle, nerve, fascia, pelvis, sphincter, urethra, urinary continence, and erectile function. Relevant articles and textbook chapters published since the last review were critically reviewed, analysed, and summarised. Moreover, we integrated aspects that were not addressed in the last review into this update.

EVIDENCE SYNTHESIS

We found new evidence for several topics. Up to 40% of the cross-sectional surface area of the urethral sphincter tissue is laterally overlapped by the dorsal vascular complex and might be injured during en bloc ligation. Denonvilliers fascia is fused with the base of the prostate in a horizontal fashion dorsally/caudally of the seminal vesicles, requiring sharp detachment when preserved. During extended pelvic lymph node dissection, the erectile nerves are at risk in the presacral and internal iliac area. Dissection planes for nerve sparing can be graded according to the amount of tissue left on the prostate as a safety margin against positive surgical margins. Vascular structures can serve as landmarks. The urethral sphincter and its length after RP are influenced by the shape of the apex. Taking this shape into account allows preservation of additional sphincter length with improved postoperative continence.

CONCLUSIONS

This update provides additional, detailed information about the surgical anatomy of the prostate and adjacent tissues involved in RP. This anatomy remains complex and widely variable. These details facilitate surgical orientation and dissection during RP and ideally should translate into improved outcomes.

PATIENT SUMMARY

Based on recent anatomic findings regarding the prostate and its surrounding tissue, the urologist can individualise the dissection during RP according to cancer and patient characteristics to improve oncologic and functional results at the same time.

Morphological study of the neurovascular bundle to elucidate nerve damage in pelvic surgery

PURPOSE

Postoperative sexual and urinary dysfunction may occur after rectal cancer surgery involving the pelvis, but this problem cannot be solved. The aim of this study was to examine the nerve morphology of the neurovascular bundle in cadavers to determine possible causes of nerve damage during surgery.

METHODS

Twenty-two formalin-fixed cadavers were used in the study. The cadavers were donated to the Tokyo Medical University. The study comprised histological evaluation of paraffin-embedded bilateral neurovascular bundle specimens from the cadavers. Four slides of 3-cm thick were made every 1 cm in a plane perpendicular to the rectum towards the pelvic floor from the peritoneal reflection in bilateral neurovascular bundles in 22 cadavers. The number of nerves, the mean nerve area, and the mean nerve diameter were measured in each slide.

RESULTS

The results were categorized into cases with high (group H) and low (group L) positions of the pelvis 1 cm above and 2 cm below the peritoneal reflection, respectively. There was no significant difference in the number of nerves between these groups. The nerve area and nerve diameter were significantly smaller in group L, and these characteristics were more marked in males.

CONCLUSIONS

Our results show that the nerves of the neurovascular bundle became smaller in the deep pelvis. This may cause these nerves to be more susceptible to injury, resulting in nerve damage in the deep pelvis that leads to postoperative dysfunction. Particularly, this type of nerve damage may be a cause of postoperative sexual dysfunction in males.

A Critical Analysis of the Current Knowledge of Surgical Anatomy of the Prostate Related to Optimisation of Cancer Control and Preservation of Continence and Erection in Candidates for Radical Prostatectomy: An Update

CONTEXT

In 2010, we published a review summarising the available literature on surgical anatomy of the prostate and adjacent structures involved in cancer control and the functional outcome of prostatectomy.

OBJECTIVE

To provide an update based on new literature to help the surgeon improve oncologic and surgical outcomes of radical prostatectomy (RP).

EVIDENCE ACQUISITION

We searched the PubMed database using the keywords radical prostatectomy, anatomy, neurovascular bundle, nerve, fascia, pelvis, sphincter, urethra, urinary continence, and erectile function. Relevant articles and textbook chapters published since the last review were critically reviewed, analysed, and summarised. Moreover, we integrated aspects that were not addressed in the last review into this update.

EVIDENCE SYNTHESIS

We found new evidence for several topics. Up to 40% of the cross-sectional surface area of the urethral sphincter tissue is laterally overlapped by the dorsal vascular complex and might be injured during en bloc ligation. Denonvilliers fascia is fused with the base of the prostate in a horizontal fashion dorsally/caudally of the seminal vesicles, requiring sharp detachment when preserved. During extended pelvic lymph node dissection, the erectile nerves are at risk in the presacral and internal iliac area. Dissection planes for nerve sparing can be graded according to the amount of tissue left on the prostate as a safety margin against positive surgical margins. Vascular structures can serve as landmarks. The urethral sphincter and its length after RP are influenced by the shape of the apex. Taking this shape into account allows preservation of additional sphincter length with improved postoperative continence.

CONCLUSIONS

This update provides additional, detailed information about the surgical anatomy of the prostate and adjacent tissues involved in RP. This anatomy remains complex and widely variable. These details facilitate surgical orientation and dissection during RP and ideally should translate into improved outcomes.

PATIENT SUMMARY

Based on recent anatomic findings regarding the prostate and its surrounding tissue, the urologist can individualise the dissection during RP according to cancer and patient characteristics to improve oncologic and functional results at the same time.

Concepts of the rectovaginal septum: implications for function and surgery

INTRODUCTION

In the pelvis, the rectogenital septum (RGS) separates the urogenital compartment from the digestive compartment. In men, it corresponds to Denonvilliers' rectoprostatic fascia or rectovesical septum (RVS). Its purpose-and, indeed, its existence-are controversial in women. The purpose of this review was to update knowledge about the RGS in women and, in particular, to clarify its relationship to pelvic nerves in order to deduce practical consequences of pelvic surgery and compare it to the RVS in men.

METHODS

A review of the anatomical and surgical literature was undertaken. Evidence for embryological origin, composition, and surgical importance of the RGS in women and men is suggested.

RESULTS

This manuscript presents evidence of the existence of the RGS in both women (rectovaginal septum, RVaS) and men (rectovesical septum, RVS). It originates from the genital structures and extends from the rectogenital pouch to the perineal body. It is composed of connective tissue associated with bundles of smooth muscle cells and has lateral expansions in close contact with neurovascular bundles originating from the inferior hypogastric plexus. During pelvic surgery for carcinoma, preservation of nerve fibers of erectile bodies is necessary if possible. The RGS is thus an important surgical landmark during urogenital sinus surgery, prolapse surgery, and proctectomy in women as well as during proctectomy and prostatectomy in men.

CONCLUSIONS

The RGS is present in women as well as in men, with great similarities between the two sexes. It represents an important surgical landmark during pelvic nerve-sparing surgery.

Investigation of factors affecting hypothermic pelvic tissue cooling using bio-heat simulation based on MRI-segmented anatomic models

This study applied a simulation method to map the temperature distribution based on magnetic resonance imaging (MRI) of individual patients, and investigated the influence of different pelvic tissue types as well as the choice of thermal property parameters on the efficiency of endorectal cooling balloon (ECB). MR images of four subjects with different prostate sizes and pelvic tissue compositions, including fatty tissue and venous plexus, were analyzed. The MR images acquired using endorectal coil provided a realistic geometry of deformed prostate that resembled the anatomy in the presence of ECB. A single slice with the largest two-dimensional (2D) cross-sectional area of the prostate gland was selected for analysis. The rectal wall, prostate gland, peri-rectal fatty tissue, peri-prostatic fatty tissue, peri-prostatic venous plexus, and urinary bladder were manually segmented. Pennes' bioheat thermal model was used to simulate the temperature distribution dynamics, by using an in-house finite element mesh based solver written in MATLAB. The results showed that prostate size and periprostatic venous plexus were two major factors affecting ECB cooling efficiency. For cases with negligible amount of venous plexus and small prostate, the average temperature in the prostate and neurovascular bundles could be cooled down to 25 °C within 30 min. For cases with abundant venous plexus and large prostate, the temperature could not reach 25 °C at the end of 3 h cooling. Large prostate made the cooling difficult to propagate through. The impact of fatty tissue on cooling effect was small. The filling of bladder with warm urine during the ECB cooling procedure did not affect the temperature in the prostate or NVB. In addition to the 2D simulation, in one case a 3D pelvic model was constructed for volumetric simulation. It was found that the 2D slice with the largest cross-sectional area of prostate had the most abundant venous plexus, and was the most difficult slice to cool, thus it may provide a conservative prediction of the cooling effect. This feasibility study demonstrated that the simulation tool could potentially be used for adjusting the setting of ECB for individual patients during hypothermic radical prostatectomy. Further studies using MR thermometry are required to validate the in silico results obtained using simulation.

Transection versus preservation of the neurovascular bundle of the lesser omentum in primary Roux-en-Y gastric bypass surgery

BACKGROUND

A gastric pouch in Roux-en-Y gastric bypass (RYGB) surgery can be created after transection of the perigastric neurovascular bundle or by preserving these structures. Some surgeons choose to transect the neurovascular bundle (NBT), containing branches of the vagus nerve, because this might be related to additional weight loss, whereas others advocate preservation (NBP) to reduce postoperative complications.

OBJECTIVES

This study assessed the effect of both techniques after primary RYGB.

SETTING

All patients undergoing primary RYGB in a large bariatric center in the Netherlands between January 2010 and December 2013 were included.

METHODS

Patient demographic characteristics, operative details, postoperative complications and weight loss after 1 year were retrospectively analyzed.

RESULTS

A total of 773 consecutive patients were included (85.5% female). NBT was performed in 407 patients (52.7%), whereas NBP was performed in 366 patients. There were no missing data and 81.2% of patients completed the 1-year follow-up. Postoperative complications were found in 66 patients (8.5%). A total of 49 patients (6.3%) either had an anastomotic leakage, postoperative bleeding, or intraabdominal abscess (NBT 8.8% versus NBP 3.6%, P = .003). Percentage total weight loss (NBT 34.5%±6.9% versus NBP 33.4%±6.9%; P = .011) differed to a lesser extent between groups, although this was significant. Neurovascular bundle transection was identified as independent factor among others for occurrence of leakage, bleeding, and abscess development (OR 2.886; 95% CI [1.466-5.683]; P = .002).

CONCLUSIONS

Transection of the neurovascular bundle in RYGB is associated with more complications. Furthermore, weight loss is not relevantly increased. Further research is necessitated to substantiate these findings.

Protocol for Removal of Third Molar Root Tips from the Inferior Alveolar Canal-Crossing the line

INTRODUCTION

The safe removal of third molars involved with the inferior alveolar canal (IAC) has been an area of concern since long. Many times we hesitate for the removal of third molars, fearing injury to the inferior alveolar nerve.

MATERIALS AND METHODS

The authors here describe a simple technique which can be used to remove third molars showing evidence of proximity to IAC on presurgical radiographic evaluation, as well as those root tips which, during removal, accidentally enter the IAC space.

CONCLUSION

A step-by-step protocol is presented along with necessary precautions during the operative procedure.

Novel anatomical identification of nerve-sparing radical prostatectomy: fascial-sparing radical prostatectomy

Radical prostatectomy (RP) became a first choice of treatment for prostate cancer after the advance in nerve-sparing techniques. However, the difficult technical details still involved in nerve-sparing RP (nsRP) can invite unwanted complications. Therefore, learning to recognize key anatomical features of the prostate and its surrounding structures is crucial to further improve RP efficacy. Although the anatomical relation between the pelvic nerves and pelvic fascias is still under investigation, this paper characterizes the periprostatic fascias in order to define a novel fascial-sparing approach to RP (fsRP), which will help spare neurovascular bundles. In uroanatomic perspective, it can be stated that nsRP is a functional identification of the surgical technique while fsRP is an anatomic identification as well. The functional and oncological outcomes related to this novel fsRP are also reviewed.

A comprehensive review of neuroanatomy of the prostate

Although oncologic efficacy is the primary goal of radical prostatectomy, preserving potency and continence is also important, given the indolent clinical course of most prostate cancers. In order to preserve and recover postoperative potency and continence after radical prostatectomy, a detailed understanding of the pelvic anatomy is necessary to recognize the optimal nerve-sparing plane and to minimize injury to the neurovascular bundles. Therefore, we reviewed the most recent findings from neuroanatomic studies of the prostate and adjacent tissues, some of which are contrary to the established consensus on pelvic anatomy. We also described the functional outcomes of radical prostatectomies following improved anatomical understanding and development of surgical techniques for preserving the neurovascular bundles.

Associated lateral process and posteromedial tubercle talus fractures with entrapment of the medial neurovascular bundle: a case report

This paper describes a case of an isolated fracture of the lateral process of the talus associated with a fracture in the posteromedial tubercle of the talus with entrapment of the medial neurovascular bundle. Currently no similar cases have been published describing this type of neurovascular bundle injury. Furthermore, in contrast to previously published cases, both fractures were treated surgically despite the absence of posteromedial tubercle fracture displacement. This article reviews the literature and provides useful recommendations for the clinical management of similar cases in the future.

Prostatic fascia and recovery of sexual function after radical prostatectomy: Is it a "Veil of Aphrodite" or "Veil of mystery"!

Sexual dysfunction is one of the most controversial aspects associated with radical prostatectomy. Since Walsh's description of neurovascular bundle there have been number of articles describing various modification to the technique of bilateral nerve sparing to augment the recovery of sexual function. There is a very thin line between performing an ideal nerve sparing and giving equally good oncological outcome in terms of negative surgical margin. “Veil of Aphrodite” nerve sparing technique was conceptualized by Menon et al. Lately other related terms have emerged in the literature e.g., “high anterior release, “curtain dissection,” or “incremental nerve sparing. Does veil technique of radical prostatectomy help improve recovery of sexual function? Do mere presence of nerves in veil account for potency? Are these nerve parasympathetic? This short review tries to find the answer of these questions in contemporary world literature.

Robot-assisted laparoscopic radical prostatectomy: an athermal anterior approach to the seminal vesicle dissection

The seminal vesicles, particularly the lateral aspect and tips, are among the closest structures to the cavernous nerves and pelvic plexus. Given this proximity it is essential that the seminal vesicle dissection be performed in an athermal and atraumatic fashion during robot-assisted laparoscopic prostatectomy (RALP). Traditionally the seminal vesicle dissection during RALP is performed by dividing the vas deferens and following it proximally to locate the tip of the seminal vesicle. Here we describe a modification to the traditional anterior approach to seminal vesicle dissection. Our modification allows the dissection to be performed athermally and efficiently with use of minimal traction. The dissection proceeds medially between the two terminal vas deferens to identify the medial surface of one of the seminal vesicles. This medial surface is avascular and can be developed easily along the length of the vesicle using blunt dissection. Once its tip is identified it is elevated with the fourth arm medially between the two vas deferens. The ipsilateral vas can then be clipped and divided below the level of the elevated seminal vesicle. The vascular supply to the seminal vesicle is then simply identified entering the lateral aspect of its tip. A hemolock clip is placed directly beneath the tip of the seminal vesicle to control its vasculature. The remainder of the dissection can be performed with sharp dissection. Using this technique the seminal vesicle can be excised entirely with minimal traction and no thermal energy. By elevating the tip medially away from the location of the pelvic plexus and cavernous nerves, inadvertent damage to these neural structures is avoided when placing the hemolock clips.