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Testicular atrophy after attempted pediatric orchidopexy for true undescended testis
Sigmund H. Ein ⁎, Ahmed Nasr, Paul W. Wales, Arlene EinDivision of General and Thoracic Surgery, Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8
Background/Purpose: A normal testis in the scrotum is the most important outcome of the attempted pediatricorchidopexy for a true undescended testis. The reports of post-orchidopexy testicular atrophy in the literaturehave ranged from non-existent to unclear. Our purpose in this study was to estimate the incidence of andassociated risk factors for post-orchidopexy testicular atrophy.Methods:We performed a retrospective review of data from children who had an attempted orchidopexy for atrue undescended testis from 1969 to 2003 inclusive. REB approval 1000011987.Results: There were 1400 attempted orchidopexies involving common (low) type (n = 1135), ectopic type(n = 174), and high type testes (n = 91). There were a total of 111/1400 (8%) atrophic testes, mostly right-
sided. 66/111 (59%) were MADE atrophic, and 45 (41%) were FOUND atrophic. Of the 1135 common type, 56(5%) were MADE atrophic. In the ectopic and high types, the incidence of post-operative testicular atrophywas 1% and 9%, respectively.The most significant risk factors associated with testes MADE atrophic were high testicle, vas problems, andpre-operative torsion.Conclusions: In this series, the incidence of post-operative testicular atrophy that was MADE was 5% in thecommon (low) type and 9% in the high type. These numbers and the above risk factors should be quoted to thecaregiver during pre-operative informed consent.
Today, orchidopexy is the fourth most common pediatric generalsurgical operation after appendectomy, circumcision and herniarepair [1]. The incidence of undescended testicle (UDT) is said to bebetween three and five percent at birth, but by one year of age 0.8% to1.6% [2]. The most important aspect of the attempted pediatricorchidopexy for a true undescended testis is the end result of a normaltestis in the scrotum [2]. However, reports of post-orchidopexytesticular atrophy in the literature have ranged from non-existent [1–12] to unclear [13–23].
Our objectives in this study were to assess the risk factorsassociated with testicular atrophy after attempted orchidopexy.
1. Methods
This was a retrospective cohort study from July 1969 to December2003 inclusive of children treated at The Hospital for Sick Children(HSC), Toronto. The following variables were collected: age, weight,side or bilateral, hormone treatment, other medical problems, type oftrue undescended testis, pre-orchidopexy complications and prob-lems, type of orchidopexy repair, intra-operative and post-operativecomplications, results (focusing on risk factors for atrophic testes).Follow-up of all the patients until their testicular problem was solved
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was carried out by the senior author with his surgical residents. Thisreview received HSC Research Ethics Board approval (1000011987).
We used the following definitions: testicular atrophy— decrease insize of the testicle by one-third or more compared to the contralateraltesticle; low (common) UDT — testis found at the mid/lower inguinalcanal (intra-canalicular) + complete indirect inguinal hernia; ectopicUDT — testis found at/outside external ring ± small indirect inguinalhernia; high undescended testis— testis found at high inguinal canal, atinternal ring (peeping testis) or intra-abdominal + complete indirectinguinal hernia. All operations were done under general anesthesiaalong with either caudal analgesia or local nerve block. Unless therewere other medical problems and/or emergencies, the majority ofthese procedures were done as elective outpatient operations.
Data were compared using Chi square for categorical variables andstudent’s T test for continuous ones. A logistic regression model wasmade with an aim to predict variables associated with post-operativetesticular atrophy. A P-value b 0.05 was considered significant.
2. Results
There were 1400 [1368 (97.8%) unilateral and 32 (2.2%) bilateral]true UDTswho had an attempted orchidopexy; the 32 bilateral ones in16 children were operated on at separate operations (Fig. 1). Themean age at operation was 5.4 years (range: 1 month to 18 years);the weight ranged between 1.9 and 113 kg. There were 55% right-sided, 44.5% left-sided and 0.5% bilateral.
Fig. 1. Types of true undescended testes that underwent attempted orchidopexy.
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From this group of 1400, there were 182 (13%) boys who had pre-orchidopexy complications and problems (excluding atrophic testes);the most common category was 64 (4.5% of 1400) secondaryorchidopexies (recurrent or redo orchidopexy; [24–28] post-opera-tive inguinal hernia repair) (Table 1).
2.1. Operative details
Therewere 1400 attempted orchidopexies involving common (low)UDT (n = 1135, 81%), ectopicUDT (n = 174, 12.5%), and highUDT (91,6.5%) (Fig. 1). There were 1348 standard (regular) repairs, for the threetypes of UDT (n = 1135 common (low), n = 174 ectopic and n = 39high) (Table 2). Within the ectopic group were five with their testeslocated in the perineum (n = 2), groin (n = 2), and thigh (n = 1).
The remaining52highundescended testes, felt to be toohigh tohavea standard (regular) repair, received one of three different repairs: one-stage open Fowler–Stephens [29] (n = 34), two-stage open Corkery[30] (Silon sheath) (n = 10) and Jones [31] (one-stage open retroper-itoneal) (n = 8). Each testis was placed in a dartos (Koop, subcutane-ous) scrotal pouch, with the entrance of the pouch narrowed by 1 or 2
Table 1Pre-orchidopexy complications and problems (excluding atrophic testes).
INCARCERATION(Inguinal hernia with undescended testis)
6
RETRACTILE(late ascent; small testis)
4
TORSION(of true undescended testis)
1
TOTAL 18
sutures. No suture was placed through the testis to fix it in positionwithin the pouch or scrotum [7,32].
Seventy-one (5%) had concomitant procedures (the commonestwas circumcision 45%).
Of the 43 (3.1%) boys in this series who had other medical problemsand were operated on, 15 (33% of 43) were of the developmental delayvariety, with almost all of the others having some kind of congenitalanomaly. Six (0.4%) were abdominal wall and/or diaphragmatic defects(omphalocele n = 3, diaphragmatic hernia n = 2, gastroschisis n = 1),and all had delayed attempted orchidopexy with 50% success.
There were 21 (1.5%) intra-operative orchidopexy complicationsand problems (including orchidectomy and considered an atrophictestis). The commonest was related to the vas. There were fiveorchidectomies (Table 3a).
2.2. Outcomes
There were 36 (2.5%) post-operative orchidopexy complications,(excluding atrophic testis) the most common of which was woundinfection (Table 3b).
MBER (% of 1400) MEAN AGE (yr) MAJORITY SIDE
4 (4.5%) 6.5 R
1 (4.3%) 1.1 R
6 (3.2%) 5.4 R
1 (0.7%) 3.6 L
2 (13%) 4.1 R
Table 2Results of attempted orchidopexy for type of true undescended testes (UDTs).
Type ofOrchidopexy
Types of true UDTs Total(TypesofTestes)
Successfulresults %
Common (Low) (n = 1135)Ectopic (n = 174)
High
Standard (regular) 1309 39 1348 93%Fowler–Stephens(1 stage, open)
34 52 71%
Corkery (2 stage,open, Silon)
10 100%
Jones (1 stage, open,retroperitoneal)
8 38%
Total 1309 91 1400 92%Successful result 74% 92%
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Therewere a total of 111/1400 (8%) atrophic testes,mostly right-sidedof which 66/111 (59%) were MADE atrophic and 45 (41%) were FOUNDatrophic (Table 4). Of the 1135 common (low) type, 56 (5%) wereMADEatrophic. In the ectopic and high types, the incidence of post-operativetesticular atrophy was 1% and 9% respectively. The median age fortesticular atrophywas 4.8 years: (range 7 days-18 years) at operation; allatrophic testicles were noted within three months postoperatively.
Risk factors were compared between children who had had post-operative testicular atrophy and children who did not. In thisunivariate analysis (Table 5a), high position of the testicle, vasproblems and pre-operative torsionwere significantly associatedwithpost-operative atrophy. This was further investigated using a logisticregression model with the outcome being post-operative atrophy(Table 5b). Variables identified in the univariate analysis were enteredin the model and remained significant including high position of thetestis, vas problems and pre-operative torsion.
3. Discussion
This is the largest reported series of pediatric orchidopexies by onepediatric surgeon and covers a 35 year period. Other similarly largereports come from several pediatric centers, but it is not clear howmany pediatric surgeons were involved in each review[9,10,19,21,33–37.] Although there were a total of 1881 boys initiallyevaluated in this series with a total of 2039 possible UDTs, not all ofthese were true undescended testes; this was also a similarobservation in other series [3,4,11,21,38,39]. Only 1400 attemptedorchidopexies for true UDTs were included in this series (Fig. 1) and536 true UDTs were not operated on. The commonest reason wasdevelopmental delay (25%). Sixty-three boys with so-called vanishingscrotal testicles (from prenatal torsion of a descended testicle) and 40post-testicular torsion orchidopexies in normally descended testeswere also not counted as true UDT in this series. Some authors haveincluded the latter two categories in their overall total of UDT andorchidopexies [16,20,21,24,29,33,35,37].
Although the optimum age recommended for orchidopexy wasbetween nine and 12 years in the 1950 s [21], this has steadilydecreased to one year or younger [24]. Themean age of the children inthis series (as in some others [9]) was five years, although over the35 years (1969 to 2003 inclusive) of the series, the mean age had
Table 3aIntraoperative orchidopexy complications and problems (including atrophy *) [n = 21,1.5% of total].
Vas Deferens n = 16a) NO Vas n = 9b) Not connected with testis n = 6c) Cut n = 1
Orchidectomy * n = 5d) Unable to bring testis down n = 4e) Torsion of undescended testicular dermoid n = 1
decreased from six years in the first half of this series to four years inthe latter half. The lack of conformity of this series to therecommended age for orchidopexy is thought to be due to the localreferral patterns. The accepted reason for the previous older ageorchidopexy was that the infertility of these undescended testes wasblamed on their congenital aspect; presently, the surgical treatment isdone between one and two years before the germ cells disappear fromthe undescended testis [40–42]. Supporting this younger operativeapproach, Michikawa [13] showed that orchidopexy at less than twoyears of age prevented morphological changes in the repairedundescended testis [43]. Nonetheless, D’Agostino [44] has reportedthat “the timing of surgery and the anatomical position of thecryptorchid testes do not seem to affect the fertility rate”.
More than half of the 1400 true undescended testes were on theright side, as in other series [21,33], but there were only 32 (2.2%)bilateral testes in 16 patients in our series compared with 20% inGross’ series, [21] and 10% reported by Heiss [20]. There is no apparentexplanation for this discrepancy. Bilateral UDTs were never repairedat the same time in this series and their operations were usuallyseparated by at least three months until the final outcome of the firstorchidopexy was determined [21]. If that outcome was not satisfac-tory, a second surgical opinion was obtained for the patient.
Hormone treatment was never as popular in North America as it wasin Europe during the 35 years of this series [22,24]. Moreover, humanchorionic gonadotropin (hCG) has recently been replaced by luteinizinghormone-releasing hormone (LHRH) [24]. In this series, hCGwas the onlyhormone used and only in 17 (1.2%) boys, 11 with bilateral UDT, with a45% success. Other authors have reported success rates of 6%–66% in boysolder than four yearswith bilateral undescended testes or retractile testes[10,22,24,45–47]. In unilateral UDT, only 14% of boys have successfulhormonal treatment [24].
The definition of types of true UDT can be confusing in the literature(Fig. 1). There were attempted orchidopexies in 81% of our seriesinvolving the common (low) type of UDT often referred to elsewhere asintracanalicular [24] (Table 2). The second commonest UDT was ectopic(12.5%) [48]. Hutcheson has stated that the ectopic and common types ofundescended testes are variants of the same congenital anomalywith theectopic type reported as occurring in about 10% of all UDT [48]. “Whethertestes in the superficial inguinal pouch should be labeled as ectopic iscontroversial.… Truly ectopic testes may be located in the perineum,femoral or pubopenile regions or contra-lateral hemiscrotum…”— aswasseen in only five of ours [24].
The third commonest type of UDT in our series was the high typeseen in only 6.5% of our series and consistent with the literature rangeof 5%–10% of cryptorchid boys [24].
The standard (regular) repair was tried in over 95% of UDTs fromoutside the external ring (ectopic type) up to the internal ring(common (low) type) and in some high types. It was invariably donethrough the usual pediatric inguinal hernia incision, with a lateralextension if needed (Table 2). The standard repair was inadequate injust over half of our high intra-abdominal UDT because of very shortspermatic vessels, and one of three different repairs was tried(Table 1) [21].
A one-stage open Fowler–Stephens procedure was the commoneststrategy (n = 34), in which the vessels were divided as far away as
a) Infection n = 29i) Inguinal incision n = 18ii) Scrotal incision n = 11
b) Other scrotal incision complications n = 7i) Dehiscence n = 4ii) Bleeding n = 3
f
Table 4Atrophic* testes after attempted orchidopexy (all types true UDT).
Type of UDT Total attempted orchidopexies (% of 1400) Mean Age (yr) Majority side Total atrophic ⁎ testes FOUND Atrophic MADE Atrophic
Common (low) 1135 (81%) 5.4 R 83 27 56Ectopic 174 (12.5%) 8.6 R 4 2 2Sub-total 1309 (93.5%) 7 R 87 29
(33% of 87)58(67% of 87)
High 91 (6.5%) 4.8 R 24 16(67% of 24)
8(33% of 24)
Total 1400 5.4 R 111(8% of 1400)
45(41% of 111)
66(59% of 111)
⁎ ATROPHIC (absent, impalpable, missing, nonpalpable, not felt, no testis, nubbin, small, tiny, vanishing).
320 S.H. Ein et al. / Journal of Pediatric Surgery 49 (2014) 317–322
possible from the testis, usually providing sufficient length for anorchidopexy [18,21,29,33,49]. Gross [21] first suggested in 1953 that atwo-stage procedure may be of value by leaving the mobilizedundescended testis at the lower most part of the canal or just outsidethe external ring for a year or two. This modified (Corkery) procedure[30] where a Silon sheath was placed surrounding the cord structuresand testis in the lower inguinal canal until the second stage was usedin 10 cases in this series. The third procedure was a small McBurney-like lower quadrant abdominal incision to explore the retroperitonealarea and, if possible, mobilize the intra-abdominal testis [31,35]. ThisJones procedure was attempted in eight instances, but if the vesselsrequired division, it was included under the Fowler–Stephensapproach [29]. Four testes (0.2%) required removal because theycould not be brought down close to the scrotum, even after theFowler–Stephens [29] or Jones [31] procedures were tried; this didnot occur using the Corkery [30] procedure. With these differentoperations used over many years, surgeons have achieved surpris-ingly different results from 1%–40% success [18,21,29-31,33,35,49].
Follow-up of all the patients was carried out by the senior authorwith his surgical residents and began at two weeks. It was ourobservation that the most serious post-operative complication (testisMADE atrophic) occurred within three months. For that reason alone,the minimum follow-up was at least three months. If there was a rarepost-operative problem (e.g. wound infection), more frequent visitsbecame necessary until the problem resolved. Very few children werelost to follow-up because of the perceived importance of theorchidopexy by the family.
We believe that pre-operative, intra-operative and post-operative complications (excluding atrophic testes) have matchedresults reported in the literature. Without question success may bedefined as a “viable testis positioned in the scrotum” [2]. We havearbitrarily added that the testis must be at least two-thirds the sizeof its contralateral fellow. Nonetheless, there is much confusionin the literature about what constitutes an atrophic testis, (non-palpable [6,8,14,15,19,20,24,29,33,35,37,50–57], vanishing[6,15,16,20,37,57,58], nubbin [6,15,55,57]). We reviewed 33 papersand/or chapters on this topic written from 1953 to 2009 in which 12different words (from atrophic to vanishing) were used by authors,with 15 (45%) using up to six different words for the same thing, 10authors not mentioning testicular atrophy at all, and nine othersbeing unclear in their definition. It is hard to tell whether a smallerthan normal testis after orchidopexy was indeed consideredatrophic as it was in our series (21%). Esposito [59] claimed “that
Table 5aRisk factors associated with postoperative testicular atrophy (univariate analysis).
Risk factors MADE atrophic(n = 66)
Non-atrophic(n = 1289)
P value (b0.05)
High testicle 21.6% 5.1% 0.0001Vas problem 3.6% 0.9% 0.007Preoperative torsion 2.7% 0.6% 0.01
greater than 83% of patients…had satisfactory results. The operatedtestis was always significantly smaller compared to the normal testisbut was well vascularized”. We would have counted these “smaller”testes as atrophic.
In the literature, the incidence of atrophy after an attemptedorchidopexy for a true UDT ranges from 5% to 12% [17,34,36,49,60].In our series, although 2/3 of the total 111 atrophic testes wereMADE atrophic, the reverse was true in the high type. This suggeststhat the higher the undescended testis, the greater the chance that itwill be FOUND atrophic. No other authors have reported thisdistinction. The literature certainly agrees with the overall fact thatthe higher the undescended testis, the greater the chance oftesticular atrophy [2,49,60].
It was the policy for the patients in this series who had animpalpable testis (other than a proven true vanishing testicle from anintrauterine torsion) to be investigatedwith radiological imaging (e.g.ultrasonography (US)) to try and identify it without surgicalintervention. The former approach was successful in about 50% ofour cases and this has been similarly reported in the literature withsuccess rates of 50%–75% [6,50,52,53]. A negative finding wasunacceptable and magnetic resonance imaging (MRI) was thenrequested; this has been reported as having 65%–75% success byother authors [51]. Therefore, only if confirmation of the impalpableUDT was not made and/or was inconclusive, did the child undergoinguinal exploration [61]. The latter occurred during the first 20 yearsof this series, and after that laparoscopy with attempted orchidopexywas the procedure of choice [20,62].
There is controversy in the literature about whether a testicular“nubbin” carries a risk of malignancy and therefore requires excision[57,58]. In our series, we made no attempt to remove any residualtesticular remnants and/or nubbins (unless for technical reasons) atthe time of exploration.
The largest published series that we could find was a 1995 reviewof 8425 orchidopexies for UDT which focused on “success rates”. Inthis, Docimo [49] reviewed 70 years (up to 1995) of more than 300articles and book chapters. In his review, “success of orchidopexy(was) defined as scrotal position and absence of atrophy…”, but theresults in his review were quite variable. We were satisfied with anyposition in the scrotum, and considered a one-third decrease in thenormal size as atrophic. Some of the “successes” in the papersreviewed in Docimo’s publication were recorded as “testicularhypotrophy, decrease in testicular volume” [49]. He also classified“orchiectomy” for inability to achieve length as a failure, yet heexcluded orchiectomy as an equivalent to testicular atrophy.
Table 5bPredictors for postoperative testicular atrophy (multivariate analysis).
Table 6Atrophic testes after attempted orchidopexy (True high UDT, n = 91).
Operation Total Orchidopexies Mean Age (yr) Majority side ⁎ Total atrophic testes FOUND Atrophic MADE Atrophic
Standard (regular) 39 (43% of 91) 5.4 R 9 9 0Non-Standard 52 (57% of 91) 4.8 L 15 7 8Fowler–Stephens 34 R 10 3 ⁎7Corkery 10 L 0 0 0Jones 8 R 5 4 1
TOTAL 91 (6% of 1400) 4.8 R 24(26% of 91)
16(67% of 24)
8(33% of 24)
⁎ Includes 4 orchidectomies for testes unable to be brought down.
321S.H. Ein et al. / Journal of Pediatric Surgery 49 (2014) 317–322
In Docimo’s large review series, the result rate for his “canalicular”type was 87% compared to our 93% common (low) type, andhis “beyond the external ring” type was 92% to our ectopic 97%.His success rate for the high type was 78% compared to our 72%(Table 2) [49].
Docimo [49] also categorized his series’ results by the type oforchidopexy. He noted that “inguinal orchidopexy” was performed in66% of his cases and was successful in 88%, whereas our similar 1348standard (regular) repairs were 96.3% of our cases and had a successrate of 93% (Table 2). Their high 791 repairs that had five differentrepairs were 31% of their total cases (n = 2491) and had a successrate of 72%, but our 52 similar high cases that had three differentrepairs totaled only 3.7% of our 1400 cases and also had a success rateof 72% (Table 2). However, none of our patients had microvascularautotransplantation. Their Fowler–Stephens orchidopexies were doneboth in one stage (80%) and two stages (20%) with success rates of66% and 76% respectively. The success rate in our small group of one-stage Fowler–Stephens repairs was 71%. The Corkery two-stageorchidopexies with a Silon sheath were 72% successful in his review,83% successful with both Steinhardt [63], and Ionkov [64] and 100%successful in our 10 cases. The one-stage Jones transabdominalretroperitoneal explorations were 81% successful in Docimo’s collec-tive review as compared with our 38% success rate in just eight cases(Table 2) [49].
Since no attempt to categorize the atrophic testicle as FOUND orMADE was observed in the literature, we have some observationsabout these two types (Tables 4, 6). The FOUND atrophic true UDT, (asopposed to the vanishing scrotal testicle from the prenatal torsion of adescended testicle), is also assumed to be associated with a vascularproblem and this vanishing testis (testicular regression syndrome,regressed testes) [16] almost always occurs in utero. There does notseem to be any way of predicting it, preventing it and/or treating it.This FOUND atrophic testis occurred in 3.2% of our orchidopexies fortrue UDT, 41% of our total atrophic testes and in 67% of the high ones(Table 4). The latter are also the ones with the poorest success ratethroughout the literature [49].
Of more importance, 4.7% of orchidopexies for true UDT wereMADE atrophic; this was 59% of our total atrophic testes and wassurprisingly 67% of the lower, easier undescended testes to fix(Table 4). These are the atrophic results that are potentiallypreventable. In the literature, more than 25% of the abdominal testesbecome failures of orchidopexy, and if these high testes requiredivision of their spermatic vessels, orchidopexy fails in about 30% [49].
Finally, after looking at all factors for post-operative atrophy, onlythe high testis, vas problems and pre-operative torsion seemed to beindependent risk factors.
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