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Keywords:

  • histological;
  • fascia width;
  • interfacial;
  • nerve preservation;
  • robot prostatectomy

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Conflict of Interest
  8. References

What's known on the subject? and What does the study add?

  • Incremental nerve-sparing techniques (NSTs) improve postoperative erectile function after robot-assisted radical prostatectomy (RARP).
  • However, there are no studies to date that histologically confirm the surgeon intended NST. Thus, in the present study, we histologically confirmed that the surgeon performed the nerve preservation as his intended NSTs during RARP. Also, we found that there was more variability in fascia width outcome on the left side compared with the right. Therefore, when performing nerve preservation on the surgeon's non-dominant side, we need to pay more close attention.

Objectives

  • To confirm that the surgeon achieved true intended histological nerve sparing during robot-assisted radical prostatectomy (RARP) by studying RP specimens.
  • To aid the novice robotic surgeon to develop the skills of RARP.

Patients and Methods

  • Between June 2008 and May 2009, 122 consecutive patients underwent RARP by a single surgeon (K.K.B.). The degree of nerve sparing (wide resection [WR], interfascial nerve sparing [ITE-NS], intrafascial nerve sparing [ITR-NS]) on both sides was recorded. The posterior sectors of RP specimens from distal, mid, and proximal parts were evaluated.
  • Fascia width (FW) of each position in RP specimens were compared across nerve-sparing types (NSTs). FW was recorded at 15 ° intervals (3–9 o'clock position), measured as the distance between the outermost prostate gland and surgical margin.
  • The slides were reviewed by an experienced uropathologist who was ‘blinded’ to the NST.

Results

  • In all, 93 men were included. The overall mean (sd) FW was the greatest in the order of WR, ITE-NS, and ITR-NS, at 2.42 (1.62), 1.71 (1.40) and 1.16 (1.08) mm, respectively (P < 0.001).
  • FW was statistically significantly correlated with the surgical technique used. When the surgeon intended to perform various levels of nerve sparing, these were reflected in the FW.
  • Interestingly, the left-side FW showed more variability than the right side. We suspect that this was a result of the surgeon's right-hand dominance.
  • Erectile function (EF) recovery rate according to NST was 88.9%, 77.3%, 65.6%, 56.3%, and 0% in bilateral ITR-NS, ITR-NS/ITE-NS, bilateral ITE-NS, ITE-NS/WR, and bilateral WR, respectively.
  • To further validate and confirm these preliminary findings, additional studies involving multicentre cohorts would be required.

Conclusions

  • The surgeon intended dissection and FW correlate, with ITR-NS providing the narrowest FW and the EF recovery rate was the highest in bilateral ITR-NS. There was more variability in FW outcome on the left side than the right.
  • The novice robotic surgeon should consider this variability when performing RARP. It may have implications for technique improvement on nerve preservation for EF.

Abbreviations
EF

erectile function

FW

fascia width

ITE-NS

interfascial nerve sparing

ITR-NS

intrafascial nerve sparing

LPF

lateral pelvic fascia

NST

nerve-sparing type

NVB

neurovascular bundle

(RA)RP

(robot-assisted) radical prostatectomy

WR

wide resection

Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Conflict of Interest
  8. References

Radical prostatectomy (RP) is the surgical treatment of choice for men with clinically localised prostate cancer. Preservation of neurovascular bundles (NVB) during RP has been shown to be associated with postoperative erectile function recovery [1, 2].

In several reports [3, 4] it was recognised that the NVB is situated in a localised space in about half of cases, whereas in the rest [5, 6] it is sparsely spread to the lateral aspect, without definite bundle formation. This fact makes nerve preservation difficult to predict and it may be one of the primary reasons for variability in postoperative functional patient outcomes. Advances in our understanding of the anatomy of the prostate and new techniques during robot-assisted RP (RARP) have resulted in the description of various degrees of nerve sparing. Many recent reports of incremental nerve preservation methods have suggested improved postoperative erectile function (EF) after RP [2, 3, 7].

However, erectile dysfunction after RP remains a common concern as it has significant impact on patient health-related quality of life [3, 6, 7]. There are various factors affecting EF recovery after RP. Among them, the most important and basic factor is whether the RP was completed as per the intended anatomical dissection of the surgeon. In an effort to improve functional outcomes after RP, we think that the first step is to determine whether the intended nerve-sparing type (NST) was actually successfully achieved during RP.

In the present study, we evaluated NSTs pathologically to determine if the surgeon was able to achieve the intended nerve sparing during RARP.

Patients and Methods

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Conflict of Interest
  8. References

Between June 2008 and May 2009, 122 consecutive patients underwent RARP by a single surgeon (K.K.B.) for clinically localised prostate cancer. We reviewed the patient's pathological slides from RP specimens and compared them with our prospectively maintained urological database. To maintain standardisation on width measurements, we excluded patients who had received preoperative androgen-deprivation therapy, continuously used 5α-reductase inhibitors within 6 months before surgery, pathological stage T3 after RARP, and severe periprostatic adhesion due to inflammation, which may affect the fascia width (FW) measurement. The slides were reviewed by an experienced uropathologist who was ‘blinded’ to the NST.

For pathological processing, the specimen was divided into four sectors: right/left anterior, right/left posterior. Among these sectors, we used the right/left posterior (6–9/3–6 o'clock position on the slide) specimens (Fig. 1a). The slides were taken from the three parts (proximal, middle, and distal) of each sector (Fig. 1b).

figure

Figure 1. Schematic models. a, describes each o'clock position in the coronal section of prostate (slide view). Among sectors, we used the right/left posterior sectors (6 to 9/3 to 6 o'clock position on the slide). b, describes the three locations in the longitudinal view of the prostate. The apex and the base parts on the specimens were considered to be at the surgical margin and were excluded. The thickened line is a posterior sector of the RP specimen. Rt., right; Lt., Left; post., posterior.

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Patients were followed up at 3-month intervals and assessed for EF recovery with ≥1 year of follow-up. Sexual outcomes after RARP were attained prospectively via our questionnaire in which patients selected their erectile state; 0: no erection, 1: flaccid but fullness sense, 2: partial erection but not sufficient for penetration, 3: firm enough for penetration but still not satisfactory, 4: firm enough for penetration with satisfaction.

Definition of FW, NST and EF Recovery

We defined the FW as the distance between the outermost prostate gland and surgical margin (Fig. 3). Using an ocular micrometer, the FW was recorded at 15 ° intervals (3–9 o'clock position) in millimetres. Indication for nerve sparing was based on prostate cancer characteristics and clinical stage at diagnosis. According to the oncological criteria for treatment, the extent of NVB preservation on both sides of the gland was determined preoperatively as an ‘intention to treat’. The definition of wide resection (WR) is widely resects periprostatic tissue including the NVB. The interfascial nerve sparing (ITE-NS) is associated with dissection into the avascular plane between the prostate fascia (so called ‘prostatic capsule’) and Denonvilliers' fascia to preserve the NVB [7, 8]. The intrafascial nerve sparing (ITR-NS) implies lateral prostatic fascia (LPF) preservation, developing the plane between the prostatic fascia and NVB and incising high anteriorly over the prostate [9, 10]. Criteria for WR are gross palpable disease, clinical stage ≥T2b or clinical stage <2Tb with ipsilateral Gleason score ≥8, and >66% of ipsilateral core positive. Criteria for ITR-NS are impalpable disease, ipsilateral Gleason score ≤6, PSA level of ≤6 ng/mL, clinical T1c stage, and <33% of ipsilateral core positive.

EF recovery patients were defined as the patients who had erections adequate for vaginal penetration with satisfaction, with or without the use of a phosphodiesterase type 5 inhibitor.

The one-way anova with Bonferroni correction was used to compare the total mean difference among three NSTs. Spearman's rank correlation analysis assessed how good the relationship between the FW and the NSTs was. We used the Student t-test to compare the FW of both sides of RP specimens in the NSTs. Statistical significance in the study was considered at P ≤ 0.05.

Results

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Conflict of Interest
  8. References

In all, 93 men with full pathological slide sets and whose pathological TNM stage was pT2 were included in the analysis. The patients who had preoperative androgen-deprivation therapy (three), continuously used 5α-reductase inhibitors within 6 months before surgery (four), pT3 after RALP (nine) and severe periprostatic adhesion (seven) and follow-up loss patients (six) were excluded. The patient demographics of NST combination groups are described in Table 1. There was no open conversion case. The overall mean (sd) FW by NSTs was the greatest in the order of WR, ITE-NS, and ITR-NS at 2.42 (1.62), 1.71 (1.40), and 1.16 (1.08) mm, respectively (P < 0.001). Individual comparisons across the three parts of prostate and clock-face positions on the slide according to the NSTs are detailed in Table 2. The number (right/left) of patients in each group were 26/18 WR, 48/51 ITE-NS, and 19/24 ITR-NS (Table 3).

Table 1. Patient demographics of NST combination groups
VariablesBilateral ITR-NSITR-NS/ITE-NSBilateral ITE-NSITE-NS/WRBilateral WR
No. patients (%)9 (9.7)22 (23.7)32 (34.4)16 (17.2)14 (15.1)
Mean (sd):     
Age, years52.44 (5.38)57.71 (7.77)59.05 (6.95)60.83 (6.28)65.81 (7.90)
Body mass index, kg/m226.93 (2.95)26.08 (3.03)27.30 (4.30)27.88 (3.52)27.92 (4.09)
Preoperative SHIM23.44 (3.43)21.77 (2.56)20.16 (5.74)20.19 (5.14)14.14 (6.90)
Preoperative PSA level, ng/mL4.96 (1.26)5.54 (1.67)5.28 (2.17)7.63 (5.35)5.88 (3.25)
Prostate size, mL49.94 (12.66)51.15 (12.49)59.09 (18.61)51.35 (17.75)51.35 (17.75)
Operative blood loss, mL138.89 (79.17)147.73 (61.68)175.78 (128.34)142.19 (66.28)146.43 (81.37)
Operative duration, min157.78 (33.83)152.36 (26.90)169.41 (43.01)171.25 (35.14)178.57 (39.51)
Catheter indwelling, days9.67 (1.66)10.09 (1.66)11.09 (2.70)9.81 (3.62)11.07 (2.92)
N:     
Clinical T stage     
T1c91825118
T204756
Positive surgical margin00000
Perioperative conversion00000
Pathological Gleason score     
625921
7715231311
802012
Pathological stage:     
T2a03122
T2b02410
T2c917271312
Table 2. The mean values of FW at each position and the Spearman's rank correlation analysis between the FW and the NST
Mean (sd), mmO'clock position:
98.587.576.56
Distal:       
WR2.75 (1.59)2.77 (1.45)3.15 (1.37)3.21 (1.25)2.72 (1.63)1.44 (1.04)1.55 (1.08)
ITE-NS1.60 (1.01)1.64 (1.08)2.01 (1.64)2.18 (1.67)2.16 (1.61)1.43 (1.18)1.51 (1.22)
ITR-NS0.99 (0.44)1.13 (0.40)1.10 (0.35)1.39 (0.88)1.46 (0.90)1.32 (0.79)1.41 (0.81)
P<0.001*<0.001*<0.001*<0.001*0.006*0.7250.648
Mid:       
WR2.05 (1.22)2.25 (1.00)2.84 (1.39)3.49 (1.54)3.05 (1.59)1.28 (1.02)1.39 (1.26)
ITE-NS1.21 (0.62)1.29 (0.87)1.54 (1.20)1.88 (1.50)1.86 (1.49)0.89 (0.63)0.99 (0.68)
ITR-NS0.75 (0.42)0.85 (0.63)1.00 (0.79)1.38 (1.01)1.35 (1.05)0.91 (0.56)0.93 (0.66)
P<0.001*<0.001*<0.001*<0.001*0.001*0.6420.260
Proximal:       
WR2.26 (1.40)2.67 (1.36)3.35 (1.57)3.71 (1.73)3.04 (1.73)1.05 (0.50)1.17 (0.99)
ITE-NS1.48 (0.83)1.37 (0.92)1.70 (1.34)1.92 (1.50)1.63 (1.31)0.70 (0.45)0.83 (0.50)
ITR-NS1.04 (0.60)1.16 (0.90)1.61 (1.49)1.50 (1.24)1.30 (1.18)0.75 (0.43)0.85 (0.49)
P0.001*<0.001*<0.001*<0.001*0.001*0.4310.352
 33.544.555.56
  1. *Statistically significant in Spearman's rank correlation analysis.

Distal:       
WR2.42 (1.43)2.92 (1.67)3.53 (1.60)3.39 (1.47)2.93 (1.68)1.77 (1.30)1.83 (1.32)
ITE-NS1.95 (1.53)2.00 (1.56)2.35 (1.78)2.61 (1.86)2.39 (1.88)1.45 (1.24)1.60 (1.20)
ITR-NS1.03 (0.51)1.13 (0.77)1.47 (1.09)1.85 (1.15)1.86 (1.22)1.32 (0.81)1.43 (0.95)
P0.001*0.004*0.002*0.0062*0.043*0.10810.097
Mid:       
WR2.08 (1.42)2.01 (1.01)2.46 (1.56)3.15 (1.82)2.57 (1.46)1.56 (1.34)1.51 (1.32)
ITE-NS1.23 (0.79)1.32 (1.04)1.99 (1.54)2.51 (1.67)2.28 (1.64)1.12 (0.79)1.21 (1.01)
ITR-NS0.74 (0.56)0.81 (0.62)0.76 (0.48)0.94 (0.62)1.00 (0.67)0.73 (0.31)0.84 (0.38)
P0.002*0.001*<0.001*<0.001*0.001*0.006*0.115
Proximal:       
WR1.74 (1.40)1.94 (1.51)2.60 (2.02)3.53 (1.88)3.36 (1.84)1.40 (1.19)1.33 (1.11)
ITE-NS1.79 (1.45)2.01 (1.32)2.32 (1.53)2.80 (1.59)2.41 (1.59)1.11 (0.66)1.24 (0.80)
ITR-NS1.31 (0.99)1.24 (0.88)1.35 (1.12)1.74 (1.35)1.60 (1.43)0.74 (0.38)0.77 (0.37)
P0.1970.042*0.006*<0.001*<0.001*0.012*0.018*
Table 3. Comparison of the mean (sd) values of FW at each right and left corresponding position (o'clock position in bold) for each NST
WRITE-NSITR-NS
Right (n = 26)Left (n = 18)PRight (n = 48)Left (n = 51)PRight (n = 19)Left (n = 24)P
  1. *Statistically significant.

93 93 93 
2.34 (1.41)2.08 (1.41)0.3181.43 (0.84)1.65 (1.33)0.0820.92 (0.69)1.03 (0.90)0.489
8.53.5 8.53.5 8.53.5 
2.56 (1.29)2.34 (1.49)0.3951.43 (0.96)1.77 (1.36)0.016*1.04 (0.84)1.06 (0.88)0.893
84 84 84 
3.11 (1.45)2.87 (1.77)0.4151.75 (1.41)2.22 (1.62)0.009*1.23 (1.15)1.19 (1.01)0.866
7.54.5 7.54.5 7.54.5 
3.48 (1.52)3.36 (1.69)0.6881.99 (1.55)2.64 (1.71)<0.001*1.41 (1.29)1.51 (1.36)0.667
75 75 75 
2.94 (1.64)2.96 (1.67)0.9471.88 (1.48)2.36 (1.70)0.011*1.37 (1.20)1.49 (1.37)0.617
6.55.5 6.55.5 6.55.5 
1.25 (1.06)1.59 (1.26)0.1691.00 (0.86)1.23 (1.14)0.0631.00 (0.87)0.93 (0.84)0.657

From the Spearman's rank correlation analysis, at the 6 and 6.5 o'clock positions, the FW was independent of NSTs in the distal (P = 0.725, 0.648), the mid (P = 0.642, 0.260), and the proximal (P = 0.431, 0.352) parts of the prostate (Table 2). At the 5.5 and 6 o'clock positions, the FW was independent of NSTs in the distal (P = 0.097, 0.108) and at 6 o'clock position in the middle (P = 0.115). But the FW was dependent of NST at the 5.5 o'clock position in the middle (P = 0.006) and at the 6 and 5.5 o'clock positions in the proximal location (P = 0.018, 0.012; Table 2).

At the 7, 7.5, 8, 8.5, and 9 o'clock positions the FW was dependent of NSTs and the FW was the thickest in the WR and then ITE-NS, and the thinnest in ITR-NS (Table 2). At the 5, 4.5, 4, 3.5, and 3 o'clock positions the FWs was dependent of NSTs and the FW was the thickest in the WR and then ITE-NS, and the thinnest in ITR-NS except only at the 3 o'clock position in proximal location (P = 0.197; Table 2). There was a correlation between the FW and NSTs at the posterolateral/lateral aspects of prostate, and the FW by NSTs was the greatest in the order of WR, ITE-NS, and ITR-NS (Fig. 2). The posterolateral aspect of the prostate (right: 7, 7.5, 8/left: 5, 4.5, 4 o'clock positions) was the thickest FW portion among the various positions in all three NSTs. Microscopic findings showed an abundance of mixed adipose, vessels, and nerve tissues compared with other locations.

figure

Figure 2. Right lower quadrant sections of the prostate with three surgical techniques (x1). The LPF (narrow arrows) and surrounding tissue of prostate differs by the surgical technique. Denonvilliers' fascia (open arrow) covers the posterior surface and the prostatic fascia (thick arrows) surrounds the prostate gland. a, WR technique: the LPF covers the lateral surface and there are much adipose tissue and nerve bundles in the lateral and posterolateral region. b, ITE-NS technique: the NBV is preserved and the LPF is situated at the 8–9 o'clock position. c, ITR-NS technique: a little part of LPF is observed above the 9 o'clock position.

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figure

Figure 3. Posterolateral portion of right quadrant sections (haematoxylin and eosin, ×40). a, WR technique. The LPF (open arrow) with nerve bundles is presented. FW is 4.7 mm (black arrow line). b, ITR-NS technique. The prostatic fascia (arrow head) is shown. Note the absence of LPF and periprostatic nerve bundles. FW is 0.6 mm (black arrow line).

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figure

Figure 4. Mean FW among the surgical techniques. The mean FWs at the posterolateral portion are thicker on the left side in ITE-NS. The mean FWs are similar on both sides in other techniques (right [Rt.]; 9–6 o'clock position, left [Lt.]; 6–3 o'clock position).

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Comparing the surgical result of right and left sides according to the NSTs, there was no statistically significant difference in the result of the FW in WR and ITR-NS but there was statistically significant difference in ITE-NS (Table 3). In the ITE-NS, the FW of left lateral position (5, 4.5, 4, 3.5 o'clock positions) was much wider than the right in mirror image (7, 7.5, 8, 8.5 o'clock positions) (P = 0.011, P < 0.001, P = 0.009 and 0.016, respectively) (Table 3, Fig. 4).

In the present study, the combination of NSTs the surgeon used are bilateral ITR-NS, one ITR-NS and the other side ITE-NS, bilateral ITE-NS, one ITE-NS and the other WR, bilateral WR. EF recovery rate was 88.9%, 77.3%, 65.6%, 56.3% and 0.0% in bilateral ITR-NS, one ITR-NS and the other side ITE-NS, bilateral ITE-NS, one ITE-NS and the other WR, bilateral WR respectively (Table 4).

Table 4. EF recovery rate according to the combination of NST
Combination of NSTEF recovery, nNo EF recovery, nEF recovery rate, n/N or %
Bilateral ITR-NS818/9
ITR-NS/ITE-NS17577.3
Bilateral ITE-NS211165.6
ITE-NS/WR9756.3
Bilateral WR0140/14
Total5538 

Discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Conflict of Interest
  8. References

The method of nerve sparing performed during RP is based on clinical parameters and baseline function. Recently, there has been a plethora of publications on varying levels of NSTs and potential improved outcomes [2, 3, 7], but there are few studies that critically evaluate the correlation of surgeon intended NST and actual FW as confirmed by histopathology. To confirm the nerve preservation was done as the surgeon had intended, we reviewed the slides of the RP specimen with a microscope and compared the result with the operative record. Several descriptions of the NVB have shown variations in the distributions of autonomic fibres between different individuals [11, 12]. Tewari et al. [6] identified, in addition to the main NVB on the posterolateral border of the prostate, nerve branches running between the prostatic fascia and the LPF. The neurovascular structures tend to be located posterolaterally, but may not always form a bundle [5, 13]. As such, to improve functional outcomes after RP, surgeons try to preserve the fascia structures around the prostate much more.

However, the nomenclature of the fascia structures around the prostate is not well standardised [4, 11, 14, 15]. For the purpose of the present study, we used ‘prostatic fascia’ which surrounds the prostate gland instead of prostatic capsule because the prostate does not have a true capsule [16]. The ‘lateral prostatic fascia’ is defined as periprostatic tissue and the outer layer of the periprostatic tissue is termed the ‘lateral pelvic fascia’ [4, 13-16]. Kiyoshima et al. [11] reported that the ‘prostatic fascia’ at the apex and the base of the prostate in sagittal sections was not recognised, as the outermost region of the prostate blends smoothly with the pelvic floor and the bladder wall. Meanwhile, the prostatic fascia structure is well observed in the lateral and the posterior aspect of the section [14]. For these reasons, we excluded apex/base parts and used the posterior sector of the prostate in the present study (Fig. 1a).

In our careful review of the RP specimens, there were many cases in which it was difficult to measure the FW because the prostatic fascia is made up of a band of concentrically placed fibromuscular tissue that is an inseparable component of the prostatic stroma. And the prostatic fascia is a multi-layered structure, of variable thickness, comprising fibrous/collagenous bands, adipose tissue, small vessels, and nerves [10, 16, 17]. Because of these findings and in reference to the Savera et al. [10] study, we measured the FW of RP specimens from the outside most of the prostate gland to the surgical margin.

In the present study, the FW of the RP specimens was statistically significantly correlated with the NST at each position, except at the 6.5, 6, and 5.5 o'clock positions (Table 2). The dissection of the posterior aspect of prostate (6.5, 6, 5.5 o'clock positions) is usually performed at the layer between the rectum and Denonvilliers' fascia, and the prostate is removed with Denonvilliers' fascia in three surgical techniques, and there was little adipose tissue between the prostate fascia and Denonvilliers' fascia [11]. Therefore, at the posterior aspect of prostate, the FW was similar and independent of NST. The FW at posterolateral aspect (right: 7–8/left: 5–4 o'clock) was dependent of surgical techniques and was the thickest among every position in three parts of prostate. This finding can be explained by the fact that both posterolateral aspects are round and there are many mixed vessels, nerves and much adipose tissue components here compared with any other position (Fig. 2).

Also, at the lateral aspects (right: 9, 8.5/left: 3, 3.5 o'clock positions), the FW was statistically correlated with the NST used. The thickness of the FW tends to decrease from posterolateral aspect to lateral aspect throughout the three parts within the same technique. This may be explained by the fact that LPF and prostatic fascia are more connected and fused with each other at the lateral aspect of the prostate than the posterolateral aspect [11]. In a study by Emerson et al. [18], the mean closest distance between tumour and margin was 0.7 mm. Because the preservation of the LPF nerve (ITR-NS) requires a plane of dissection much closer to the prostate [19], there is a potential of violating its limits and causing positive margins. In the present study, the mean (sd) thinnest FW at the posterior, posterolateral and lateral aspects was 0.73 (0.31) (5.5 o'clock position, mid), 0.76 (0.48) (7 o'clock position, mid), 0.74 (0.56) mm (3 o'clock position, mid) respectively, using the ITR-NS (Table 2). Therefore, the ITR-NS for a ‘good’ outcome must be done very carefully and delicately to avoid positive margins.

To determine how these pathological results relate to clinical results, we examined the EF recovery rate of the patients. In bilateral ITR-NS, EF recovery rate was 88.9%, one ITR-NS and the other side ITE-NS: 77.3%, bilateral ITE-NS: 65.6%, one ITE-NS and the other WR: 56.3%, bilateral WR: 0.0% (Table 4).

Because EF recovery rate was in the order of bilateral ITR-NS, ITR-NS/ITE-NS, bilateral ITE-NS, one side ITE-NS from the highest to the lowest, we conclude that increased nerve sparing is related to EF recovery.

Notably, we found that the FW on the left side was thicker than the right in the ITE-NS. We postulate the reason for this difference is possibly because the surgeon is a right-hand dominant, because there have been some reports of the difference of hand dominance in laparoscopy [20, 21]. It is possible that when a right-handed surgeon dissects the left side there may be an intangible inherent difficulty with the dissection as compared with the contralateral side. The speculation about the difference between right and left sides may have no applicability to all surgeons. Nevertheless, we think this is a new and important finding because it presents the possibility of occurring to anyone during RARP. Therefore, when a surgeon is performing nerve preservation on his/her non-dominant side, closer attention should be paid.

In the present study, the surgeon performed nerve preservation as per his preoperative intent and there were some unanticipated findings. To further validate and confirm these preliminary findings, additional studies involving multicentre cohorts would be required.

In conclusion, the FW is directly dependent on the level of nerve sparing, with ITR-NS providing the narrowest width, followed by ITE-NS, then WR. The present study histologically confirms that the surgeon performed nerve preservation as his intended NST during RARP. There was more variability in FW outcome on the left side compared with the right and we suspect that this was a result of the surgeon's right-hand dominance. Although this finding may not be applicable to all surgeons, it presents the possibility of occurring during RARP. Therefore, when performing nerve preservation on the non-dominant side, we need to pay more close attention.

References

  1. Top of page
  2. Abstract
  3. Introduction
  4. Patients and Methods
  5. Results
  6. Discussion
  7. Conflict of Interest
  8. References
  • 1
    Walsh PC, Marschke P, Ricker D, Burnett AL. Patient-reported urinary continence and sexual function after anatomic radical prostatectomy. Urology 2000; 55: 5861
  • 2
    Noldus J, Michl U, Graefen M, Haese A, Hammerer P, Huland H. Patient-reported sexual function after nerve-sparing radical retropubic prostatectomy. Eur Urol 2002; 42: 118124
  • 3
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