Sexual and Reproductive Health

9. PENILE SIZE ABNORMALITIES AND DYSMORPHOPHOBIA

9.1. Definition, epidemiology and classification

9.1.1. History

Throughout history, the size of the penis has symbolised a marker of masculinity [1117] and has created intense debate in societies with different social and cultural implications [1118]. Indeed, along with the capacity for vaginal penetration, the penis is linked to an ancestral sense of men’s fertility and sexual performance, making the size of the penis a source of distinguishing male identity [1119,1120]. Evidence of male supremacy and dominance as represented by phallometric designs can be found across cultures and history and is still currently supported by contemporary media, including the pornographic industry [1121,1122].

Overall, cosmetic surgery has the potential to restore self-esteem, reduce anxiety, social phobia and depressive mood states regarding body concerns, increasing individuals’ well-being and quality of life (QoL) [1123,1124]. Yet, some candidates for cosmetic surgery may have psychopathological conditions and surgery may result in negative outcomes [1124,1125].

In the real-life setting, it is interesting to note that 84% of women report being satisfied with their male partners’ penile size whereas 55% of the male partners were satisfied with their penile size and 45% of them report that they would like to have a larger penis [1126]. In this context, men with a high level of social-desirability were more likely than others to self-report having a larger penis [1127]. A recent study also demonstrated that reducing the depth of penetration led to a statistically significant 18% reduction of overall sexual pleasure with an average 15% reduction in the length of the penis [1128].

Additionally, the subjective impression of penile size may have a negative effect on sexual functioning and QoL, impacting sexual life in about 10% of men [1129-1131]. This prevalence sharply rises in patients seeking penile augmentation procedures [1132,1133].

Furthermore, the fact that a subgroup of men does not achieve reasonable levels of satisfaction and emotional adjustment after penile augmentation procedures, underlines that with certain psychopathological conditions men will not benefit from such invasive procedures [1134]. These men may represent a psychologically vulnerable group of individuals in whom penile augmentation procedures will have negative effects and, as such, require clinical and psychological support. Clinicians should possess the skills to anticipate and address such vulnerability through a personalized psychological assessment. Additionally, they should take into account cultural norms to facilitate an understanding of patient expectations [1135].

With the increased use of penile augmentation procedures worldwide, either medical or surgical, it becomes crucial to create evidence-based recommendations to guide clinicians in this challenging and controversial area.

9.1.2. Definition

To date short penis condition represents both a diagnostic and treatment challenge [1136,1137]. An accurate measurement of the penile shaft is a mandatory step in the assessment of patients complaining of a short penis and defining the norm [1138]. Indeed, a standard tool to address penile measurements and to counsel patients seeking penile augmentation procedures is needed. To date, the standard penile size has yet to be clearly defined. Even though several investigators have attempted to provide objective measurements to define a normal penile size, there is still no consensus on this (Table 21).

Table 21: Summary of papers reporting objective penile measurements

Measurements are expressed as median/mean, (IQR)/±SD

The other factor that strongly affects penile measurements is the interobserver variability and the underestimation of the stretched penile length (SPL) when compared to the erect state [1163].

Despite the aforementioned limitations, SPL, defined as the distance between the pubic symphysis and the apex of the glans, represents the most overlapping measurement of the erect penis. Accordingly, a SPL of less than 2.5 standard deviations (SD) below the mean for the male’s age and race is considered as micropenis [1164,1165].

9.1.3. Epidemiology and Classification

The overall incidence of micropenis in the male population is not clearly documented. Epidemiological studies demonstrate that between 0.015% - 0.66% of male newborns have a micropenis [1166,1167]. There are concerns that the prevalence of this congenital abnormality is increasing due to in-utero exposure to endocrine-disrupting chemicals before and during pregnancy [1167]. Despite the limited prevalence of micropenis, there is a major demand for penile augmentation procedures worldwide. This phenomenon can be partially explained by the increased interest in pornography in recent years and the altered perception of a normal penile size [1118,1168,1169].

Due to the heterogeneity of clinical situations related to short penis conditions, a classification based on the underlying aetiology is provided below (Table 22).

Table 22: Classification of the clinical conditions underlying a short penis condition or dysmorphophobia in the adult

9.1.3.1. False penile shortness - congenital or acquired

Among causes underlying a false penile shortness, the buried penis is the only well-known condition. Historically, a buried penis has been considered a congenital disease affecting children: the so-called “concealed penis” or “webbed penis” [1170,1171]. Indeed, an abnormal development of the dartos fascia may lead to the entrapment of the penile shaft to the peri-genital tissue leading to this clinical manifestation. On the other hand, a buried penis in the adult is widely recognised as an acquired condition, termed the adult acquired buried penis (AABP) [1172].

The aetiology underlying the development of AABP is deemed to be related to a chronic inflammatory state of the penile dartos which leads to a progressive retraction and scarring of the peri-genital teguments [1173,1174]. The progressive entrapment of the phallus causes a moist environment which facilitates bacterial and fungal growth causing chronic inflammation [1175]. The ensuing fibrosis results in further entrapment of the penile shaft in the peri-genital tissue [1174,1175].

Although the exact prevalence of AABP is unknown, its incidence seems to be increasing along with the growing prevalence of obesity, which represents the main risk factor [1176]. Other factors contributing to AABP include aggressive circumcision, following surgical treatment in the obese or penile cancer (PC), or chronic dermatological conditions such as lichen sclerosis (LS) [1177-1179].

The AABP is commonly associated with erectile and voiding dysfunctions, difficulties in maintaining adequate genital hygiene and a poor QoL [1177-1179]. A summary of risk factors for AABP and underlying issues requiring surgery is detailed in Table 23.

Table 23: Summary of studies reporting clinical characteristics of patients with AABP

Measurements are expressed as median/mean, (IQR)/±SDBMI = body mass index; DM = diabetes mellitus; HT = hypertension; LS = lichen sclerosis.

The aim of AABP treatment is to restore the functional genital anatomy and to improve QoL [1177,1178]. So far, different authors have proposed a number of classifications for AABP based upon both clinical presentation and the surgical procedure required [1172,1191].

9.1.3.2. Intrinsic penile shortness – congenital

This category encompasses the so-called “true micropenis” [1199-1201]. Despite male genital malformations being recognised as the most common birth defects, they represent a rare clinical entity with a prevalence between 0.9% and 2.1% [1202,1203]. Normal genital development is under the influence of hormonal stimulation during the fetal and pubertal periods [1204]. Several genetic syndromes may cause disturbance of the physiological hormonal axis needed for a normal genital development [1199,1205]. Micropenis may also exist as an isolated finding without a definitive etiological cause in up to 25% of the cases. The classification of the clinical conditions associated with intrinsic penile shortness in the adult is presented in Table 24.

Table 24: Classification of the clinical conditions underlying intrinsic penile shortness in the adult

Amongst the pre-existing clinical entities associated with micropenis, the bladder exstrophy–epispadias complex (BEEC) is the most studied [1177,1178,1201]. It represents a spectrum of genitourinary malformations ranging in severity from epispadias to bladder exstrophy or exstrophy of the cloaca. It is considered as a rare disease, with a prevalence at birth of 1/10,000 [1199,1201,1203,1206]. Even though surgical reconstruction aims to improve body image, this clinical entity is frequently burdened by psychosocial and psychosexual dysfunctions in the long term [1207-1213]. Additionally, male infertility is frequently associated due to poor sperm quantity or quality and hormonal impairment [1214].

9.1.3.3. Intrinsic penile shortness – acquired

This category includes a series of pathological entities that lead to the shortening of the corpora cavernosa. The mechanism underlying intrinsic penile shortening can be acute, as in the case of penile trauma or surgical amputation due to penile cancer or chronic due to a progressive fibrotic process involving the corpora cavernosa [1215-1217].

Traumatic genital injuries may commonly result from traffic accidents and gunshot wounds [1217]. Rarely, a penile amputation can be the result of circumcision and genital surgical procedures such as hypospadias repair, penile prosthesis implantation or urethroplasty, and may result in a decrease in penile length [1218-1222].

Among chronic causes of penile shortening, Peyronie’s disease (PD), treatments for prostate cancer, particularly radical prostatectomy (RP) and radical cystectomy represent the most common [1132,1215,1216,1223-1231].

9.1.3.4. Body dysmorphic disorder

Body dysmorphic disorder (BDD) is a clinical diagnosis defined by the American Psychiatric Association (APA; DSM-5) as the strong distress generated by perceived defect(s) or flaw(s) in the individual’s physical appearance. This flaw is not observable to others, or, in case it exists, it appears only slightly [1232]. This condition is followed by significant impairment in important areas of the individual’s social or occupational life. Body dysmorphic disorder has been allocated to the Obsessive Compulsive and Related Disorders section [1232]. Muscle dysmorphia is a typology within BDD characterising individuals – usually men – with a strong pre-occupation with their perceived small muscles and body shape. Sometimes, men with BDD/muscle dysmorphia also present with an exaggerated focus on the size or shape of their penis. In those cases, Penile Dysmorphic Disorder (PDD) can be used as a shorthand concept – not listed in APA’s DSM-5 coding system. Both BDD and PDD are conceptually different from small penis anxiety (SPA) or small penis syndrome, which refers to a man’s excessive anxiety regarding his normal-sized penis. Small penis anxiety is not included under APA’s nomenclature but men with SPA may be at risk for BDD [1233]. All these definitions exclude men with true micropenis [1232,1234,1235]. Prevalence data shows that 2.2% of men in the USA and 1.8% in Germany suffer from BDD [1232]. Between 3%-16% of patients undergoing cosmetic surgery are expected to present BDD, a higher rate in men (15.3%) than in women (10.9%) [1236].

These psychopathological entities must be differentiated from Gender Dysphoria, i.e., the clinical distress associated with the incongruence between gender identity and the gender assigned at birth; and from Koro, i.e., sudden anxiety about the penis falling back into the abdomen [1232].

9.1.4. Summary of evidence and recommendations for classification

9.2. Diagnosis

9.2.1. Medical history, physical examination and psychological assessment

9.2.1.1. Medical History

The first step in the evaluation of short penis is a detailed medical history [1237]. Common causes of penile shortness should be screened and observed (e.g., history of phimosis, priapism, hypospadias/epispadias, penile trauma, penile cancer, prostate cancer, penile pain with or without acquired penile curvature suggestive of PD). A past or present diagnosis of BDD should also be noted.

9.2.1.2. Sexual history

Besides a comprehensive clinical interview with open questions regarding sexual education, development, or previous sexual experiences and fantasies, psychometric tools can be used. These include measurements of sexual functioning (e.g., The International Index of Erectile Function [IIEF]), sexual distress (e.g., The Sexual Distress Scale for men), and sexual satisfaction (e.g., Global Measure of Sexual Satisfaction) [307,1238,1239]. The propensities for sexual excitation and sexual inhibition may be further considered, (e.g., Sexual Inhibition/Sexual Excitation Scales), as well as measurements of relationship satisfaction (e.g., Global Measure of Relationship Satisfaction) [1239,1240]. Special focus should be put on the assessment of sexual performance expectations (e.g., The Dysfunctional Sexual Beliefs Questionnaire) [1241]. As a complementary assessment, body image perception can be further considered (e.g., The Body-Image Questionnaire).

9.2.1.3. Physical examination and penile size measurements

An accurate physical examination focused on the genital area is essential to the patient's initial assessment. The assessment of penile size and shape is mandatory to plan any subsequent medical or surgical treatment but methods for penile measurements seem to vary amongst surgeons [1138,1242]. The EAU Guidelines Panel on Sexual and Reproductive Health considers a stretch penile length measurement as the bare minimum. If possible, the Panel also advocates additional measurements in both flaccid and erect state after intracavernosal injection of erectogenic agents, compulsory before any surgical indication. Stretched penile length (SPL) can be measured both dorsally and/or ventrally from the penopubic skin junction-to-glans tip (STT) or dorsally from the pubic bone-to-glans tip (BTT) using either a measuring tape or a Vernier calliper. Overall, the measurement of penile size has not been standardised and to date there is no consensus definition due to high heterogeneity in terms of data assessment and reporting methodologies amongst different studies [1242].

Moreover, penile girth should be noted in every patient. As for girth, both distal (coronal) and mid-shaft measurements should be recorded. Furthermore, both measures of circumference can be compared to the head-to-base ratio. The former can help classify penile shape which can be documented through photography [1243]. Although used as a surrogate, STT underestimates erect penile length by about 20% [876,1244]. Nonetheless, it is important to note that BTT seems to have a better correlation with erect penile length, especially in overweight and obese men [876].

Table 25: Penile size measurement

9.2.1.4. Psychological assessment

A sub-group of men requesting penile augmentation procedures, usually surgery, present with strong psychological vulnerability, including BDD [1233]. This subgroup of men may be at risk for increasing psychopathology and suicide attempts and will be unlikely to achieve their surgery expectations [1245]. Currently, there is a set of freely available self-reported tools that may be used to screen patients at risk for psychopathology or poor surgical outcomes, including the Body Dysmorphic Disorder Questionnaire and The Cosmetic Procedure Screening Scale for Penile Dysmorphic Disorder, screening for psychopathological cases regarding body and penile dysmorphic disorder [1233,1246]. Likewise, The Male Genital Self-Image Scale, and the Index of Male Genital Image, measure men’s perceptions and satisfaction regarding their genitals [1247,1248]. In addition, the Beliefs About Penile Size Scale captures beliefs about the size of the penis as well as internal psychological processes [1249]. However, evidence on BDD/PDD, further psychopathological comorbidities, and the differential diagnosis regarding personality disorders, and disorders from the obsessive-compulsive, psychotic, or emotional spectrum, should be performed by an accredited mental health expert. In addition, the subjective penile size perception should be evaluated [1134].

9.2.1.5. Counselling and outcomes assessment - Validated questionnaires

The Augmentation Phalloplasty Patient Selection and Satisfaction Inventory (APPSSI) questionnaire is a 5-item questionnaire proposed for the assessment and counselling about penile augmentation surgical treatment [1250]. The Beliefs about Penis Size (BAPS) is a 10-item questionnaire created for audit and outcome research to assess men’s beliefs about penile size [1249]. Both questionnaires have failed to correlate with penile size and lack of objective validation has restricted their use.

Other well-known self-reported psychosexual questionnaires may be considered: the IIEF-15 and the Male Sexual Health Questionnaire (MSHQ) should be administered to record baseline sexual function status and can also be used to assess its changes after treatment; the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) can also be helpful to assess patient and partner's treatment satisfaction [307,1251,1252].

9.2.2. Imaging

There is a lack of evidence regarding the use of imaging techniques in the assessment of patients complaining about penile shortness. Although a penile Doppler ultrasound or a penile magnetic resonance imaging may provide additional data regarding the penile anatomy and the extent of penile burying, there is no evidence that this additional information could contribute to the physical examination to justify its routine use in this clinical scenario [1138,1253-1256].

9.3. Management

9.3.1. Non-surgical Treatments

9.3.1.1. Psychotherapy

Penile augmentation is often motivated by the desire to improve self-perception and self-esteem [1257]. Cosmetic treatments may help increase individuals’ well-being and QoL, improving self-esteem and emotional states [1123,1124,1138]. Still, psychotherapy is recommended when psychopathological comorbidities are detected, or when aversive relationship dynamics may underly the request for penile augmentation. Addressing patients’ and partners’ motivations and expectations regarding penile augmentation seems to be a key psychotherapeutic target while no other empirical evidence is described. Similarly, men with BDD and SPA present a significant discrepancy between the perceived and ideal size of the penis, internalising the belief they should have a larger penis [1258]. Cognitive behaviour therapy for BDD could be applied to cases of anxiety regarding penis size, although no clinical trials have been reported [1259]. In all, it is worth noting that psychotherapy should normalise the great variability of genital shape and size [1133]. Managing patient expectations could be a means to improve results and well-being associated with the surgery process.

9.3.1.2. Penile traction therapy

Despite the various surgical techniques, there are also non-invasive methods that are used to enhance penile length, including penile traction therapy (PTT) [1260]. In a pilot phase-II prospective study that evaluated the efficacy and tolerability of a penile-extender device in the treatment of short penis, Gontero et al., used the same traction device for at least 4 hours/day for 6 months and achieved a significant gain in length, of +2.3 and +1.7 cm for the flaccid and stretched penis, respectively (both p < 0.001) [1261]. However, the change in the penile girth was not significant. In a further prospective study, these results were confirmed by Nikoobakht et al., who found a significant improvement in the mean length both for the flaccid (8.8 ± 1.2 cm to 10.5 ± 1.2 cm, P < 0.05) and the stretched state (11.5 ± 1.0 cm to 13.2 ± 1.4 cm, p < 0.05) following 3 months of use of a penile traction device [1262]. At six-month follow-up, compared to baseline, a mean gain of +1.7 ± 0.8, +1.3 ± 0.4, and +1.2 ± 0.4 cm was reported for the flaccid, stretched, and erect penile lengths, respectively (p < 0.001, for all). The broad spectrum of available PTT studies is summarised in Table 26.

Overall, PTT seems effective in lengthening the penis both in the flaccid and stretched state with minimal side effects. Yet it is not effective for penile girth enhancement. However, the quality of evidence is poor due to the lack of RCTs, and the availability of only heterogeneous and small PTT cohorts has also been proven effective in the restoration of length or correction of deformities due to several diseases, including PD, or post-RP conditions [955,1263-1265].

Table 26: Penile traction therapy (PPT)

NR = not reported.

9.3.1.3. Vacuum erection device

Vacuum erection devises (VED) are generally considered for patients who fail oral ED therapies [413,1237]. In contrast, data regarding the use of VEDs on penile elongation is scarce. In a study with 27 men whose SPL was < 10 cm, the use of a VED three times a week for 20 minutes on each occasion, for six months, did not result in a significant increase in flaccid or SPL [1267]. On the other hand, the benefits of using a VED following PPI and RP have been demonstrated in the literature [1267-1272].

9.3.1.4. Endocrinological therapies

Testosterone administration has been used for a long time to increase the length of the penis in infant or pre-pubertal boys with micropenis. Topical administration of T or DHT has also been proposed by other authors with reported better outcomes with DHT, especially in poor responders to T or in those with type 2 alpha reductase deficiency [1273,1274]. Finally, the possible use of the combination of hCG and FSH treatment has also been proposed with positive outcomes [1275,1276]. Despite the treatment suggested it should be recognised that no face-to-face comparisons are available so far.

9.3.1.5. Summary of evidence and recommendations for the non-surgical management of short penile size

9.3.2. Surgical Treatments

9.3.2.1. Surgical treatment of adult acquired buried penis

9.3.2.1.1. Adult acquired buried penis surgical procedures classification

According to the classification proposed by Pariser et al. different procedures may range from low complexity (including un-burying of penile shaft, reconstruction of penile shaft with the use of skin flaps or grafts, plastic surgical techniques to reconstruct the scrotum) to high complexity [including surgical removal of the suprapubic fat pad (escutcheonectomy) and operations to skin and subcutaneous fat layers of the abdominal wall (apronectomy] [1191].

The purpose of any surgical approach is to unbury the penile shaft, reconstruct genital teguments and eventually remove peri-genital or excess abdominal tissue in order to reduce the risk of recurrence. The goal is to balance an effective surgical procedure aiming to improve patient QoL, while minimising the incidence of postoperative complications. Lifestyle changes and risk factors modification, particularly weight loss, are widely considered as a proactive approach to minimise AABP surgical complications and should be encouraged before surgical intervention is undertaken. The broad spectrum of surgical interventions described to manage AABP is summarised in Table 27.

Table 27: Surgical interventions to manage adult acquired buried penis 

The current evidence highlights the efficacy of AABP surgical treatment which has a low incidence of recurrence and satisfactory functional outcomes, as shown in Table 28, yet there is a significant incidence of post-operative complications (up to 3.5% of grade V according to Clavien-Dindo Classification) [1277].

Table 28: Surgical and functional outcomes of adult acquired buried penis repair [1174]

9.3.2.2. Surgical treatment of congenital intrinsic penile shortness

Current literature reports a wide spectrum of possible surgical interventions aimed to address penile shortness. Nonetheless, the proposed spectrum of surgical interventions starts from less invasive procedures - such as suspensory ligament release (SLR) - to more complex genital reconstruction - such as total phallic reconstruction (TPR) [1278,1279].

9.3.2.2.1. Suspensory ligament release (SLR)

This technique involves a surgical incision and SLR of the penis which attaches the penis to the pubic bone. The surgical access is via an infrapubic incision and may be combined with an elongating V-Y skin plasty [1279]. Several authors reported outcomes of SLR in the context of a congenital intrinsic penile shortness (Table 29).

Table 29: Suspensory ligament release [1278]

Measurements are expressed as median/mean, (IQR)/±SD.

9.3.2.2.2. Ventral phalloplasty/scrotoplasty

This intervention is based on a ventral shaft skin plasty to move the peno-scrotal angle proximally and increase the exposure of the penile shaft. A longitudinal incision or Z-plasty at the penoscrotal junction, securing the tunica albuginea to the proximal tunica dartos was performed by Xu et al. in 41 patients [1281]. The correction was successful in all patients with an improved median length of +2.1 cm in the flaccid state.

9.3.2.2.3. Suprapubic lipoplasty/liposuction/lipectomy

This intervention aims to reduce the thickness of the suprapubic fat pad either with a minimally invasive approach (liposuction) or surgically (lipectomy). The flattening of the suprapubic fat pad aims to increase penile shaft exposure.

Ghanem et al., performed liposuction in ten patients using a 50-cc syringe with a 3- and 6-mm liposuction needle [1195]. The amount of fat removed ranged from 325 to 850 mL with a mean of 495.50 ± 155.39 mL. Three (30%) of the patients were very satisfied with the post-operative result, five (50%) patients were satisfied, one patient (10%) was neither satisfied nor dissatisfied, and one (10%) patient was dissatisfied. No patients were very dissatisfied. Shaeer’s monsplasty technique was investigated in 20 patients [1282]. At three months post-operatively, the flaccid visible length was 7.1 ± 2.1cm, with a 57.9% improvement in length, and the erect visible length was 11.8 ± 2.1cm, with a 32% improvement in length. At final follow-up (eighteen months) a 73.1% improvement in satisfaction rate was detected.

9.3.2.2.4. Total phallic reconstruction (TPR)

This represents the most complex genital reconstruction possible, aiming to create a new phallus with a neo-urethra. The operation is reserved for severe penile insufficiency cases (e.g., congenital micropenis, exstrophy-epispadias complex) as the benefit should be balanced over possible complications [1278].

Lumen et al., treated seven male patients (aged 15 to 42 years) with phalloplasty (6 with radial forearm free flap and 1 with anterolateral thigh flap) and implant surgery was offered approximately 1 year after the phallic reconstruction [1283]. There were no complications after surgical formation of the neophallus. Two complications were reported in the early post-operative period. Two patients developed urinary complications (stricture and/or fistula). Patient satisfaction after surgery was high in six cases and moderate in one case. Four patients underwent penile implant surgery and 50% were subsequently removed.

Perovic et al., conducted TPR using musculocutaneous latissimus dorsi (MLD) in twelve patients [1284]. The mean (range) follow-up was 31 (6–74) months, and the penile size was 16 (14–18) cm long and 13 (11–15) cm in circumference. There was no flap loss or partial skin necrosis.

Garaffa et al., reported a series of TPR using the radial artery forearm free flap in 16 patients with bladder/cloacal exstrophy and micropenis-epispadias complex [1285]. In one patient the distal third of the phallus was lost due to acute thrombosis of the arterial anastomosis immediately post-operatively. Almost all (93%) were fully satisfied in terms of cosmesis and size. Urethral stricture and fistula were the most common complications, which developed only at the native neourethral anastomosis. They were successfully managed by revision surgery. Sexual intercourse was achieved in 11 of the 12 patients who underwent PPI.

9.3.2.2.5. Summary of evidence and recommendations for surgical treatment of congenital intrinsic penile shortness

9.3.2.3. Surgical treatment of acquired penile shortness

9.3.2.3.1. Penile prosthesis implantation (PPI)

The literature fails to show a direct relationship between PPI and penile length in men with ED and no concomitant PD. In a study by Deveci et al., SPL was evaluated in men undergoing primary implant surgery due to diabetes or RP [1286]. Either three-piece (Alpha-1, Mentor, USA) and two-piece implants (Ambicor, AMS, Boston Scientific, USA) were used and most patients (72%) reported a subjective decrease in penile length, although no statistically significant difference was demonstrated in measured SPL [1286]. In another study, 45 patients with PD with no deformity or penile curvature < 30° or severe penile fibrosis/scarring were implanted with an AMS 700 LGX [1287]. The mean stretched penile length improved from 13.1 ± 1.2 cm to 13.7 ± 1.1 cm and 14.2 ± 1.2 cm at six and twelve months, respectively. A significant difference was also observed in the length of the stretched flaccid penis between six and twelve months [1287].

Some authors have evaluated the erect penile length following PPI. In a prospective study where patients with PD were excluded, erect penile length was compared from baseline achieved by intracavernosal injection and after PPI inflation. The authors demonstrated that there were 0.83 ± 0.25, 0.75 ± 0.20 and 0.74 ± 0.15 cm decreases in erect penile length six weeks, six months, and one year post-operatively, respectively [1288]. A study where patients with PD were excluded confirmed these results as the median pre-operative pharmacologically induced length (14.25 ± 2 cm) was decreased to median post-prosthesis penile length (13.5 ± 2.13 cm) [1289].

9.3.2.3.2. Penile disassembly

Penile disassembly has been described as a technique for penile lengthening [1290]. It consists of the separation of the penis into its anatomical components and the insertion of autologous cartilage in the space created between the glans cap and the tip of corpora cavernosa. Perovic et al., in a study with 19 patients submitted to penile disassembly and implantation of autologous rib cartilage followed by VED therapy, reported an increase of 3 cm and 3.1 cm in SPL and erect length, respectively [1290]. The results of this surgery are poorly documented and significant complications such as glans necrosis can ensue.

9.3.2.3.3. Lengthening corporal manoeuvres

Penile length restoration with the use of the sliding technique (ST) and concomitant PPI was first described in a small series of three patients in 2012, and further supported by a larger series of 28-patient in a multi-centre study in 2015 [1110,1114]. Although this technique is only used in cases of end-stage PD with severe shortening of the shaft, 95% of men were satisfied with their increase in length with an average penile lengthening of 3.2 cm (range, 2.5-4 cm). The modified sliding technique (MoST) and multiple slit technique (MuST) are further modifications of the original ST [1111,1112]. In a series by Egydio et al., 143 patients with penile shortening and narrowing due to PD amongst other aetiologies underwent MoST or MuST procedures. The mean (range) penile length gain was 3.1 (2-7) cm at a median (range) follow-up of 9.7 (6-18) months [1111].

9.3.2.3.4. Total phallic reconstruction (TPR)

Radial forearm free flap is the most used reconstructive approach for TPR. In a single-centre study, Falcone et al., reported their experience of ten patients who underwent TPR using RAFFF after traumatic penile loss [1291]. In six individuals, the urethral stump was sufficient for primary anastomosis and neourethra formation. The remaining patients had total penile avulsion and were voiding via a perineal urethrostomy. Consequently, a two-stage urethroplasty was necessary. Two patients developed an acute arterial thrombosis of the microsurgical anastomosis, which was successfully treated with emergency exploration. One patient had a neourethral stricture and fistula that required revision. All patients who underwent complete urethral repair were able to void and ejaculate through the phallus. After a median follow-up of 51 months, all patients were satisfied with the acquired size, cosmesis, and sensation. Six patients received a PPI and were able to also engage in penetrative intercourses. However, three patients had revision surgery (two due to infection and one due to mechanical failure) [1291].

9.3.2.3.5. Summary of evidence and recommendations for surgical treatment of acquired penile shortness

9.3.2.4. Penile girth enhancement

9.3.2.4.1. Penile Girth enhancement history

Nomograms were created for penile girth measurements, including flaccid penis circumference (n = 9407, 9.31 ± 0.90 cm) and erect circumference (n = 381, 11.66 ± 1.10 cm) [1136]. Unlike penile lengthening, there are no precise definitions or indications for penile girth enlargement in the literature or existing international guidelines [1292]. In recent years, men have increasingly approached urologists for penile girth enhancement to increase their self-confidence, to be cosmetically satisfied or to satisfy their partners [1293]. Current reports on penile girth enhancement techniques are from recent years [1293,1294]. Although these surgical techniques are more and more frequently requested, the level of evidence for their use in clinical practice is low, notwithstanding the ethical considerations of surgery in this vulnerable group of patients.

9.3.2.4.2. Injection therapy

Injectable filling materials can be classified according to their different properties. They can be autologous, biological or synthetic. The fat injection material is obtained from the patient’s own tissue (autologous), usually by liposuction (see the following surgical therapy section). Biological fillers can be of human and animal (collagen) or bacterial (Hyaluronic acid) origin. Poly-l-lactic acid (PLA), hydroxyethyl methacrylate, polyalkylimide hydrogel (PAAG), polymethylmethacrylate (PMMA), calcium hydroxyapatite (CHA), silicon and paraffin constitute filler materials of synthetic origin (Table 30) [1295].

Table 30: Origin of injectable filling materials

9.3.2.4.2.1. Soft tissue fillers (Hyaluronic acid and PMMA)

Hyaluronic acid

Injection of hyaluronic acid (HA) gel is one of the most commonly used injectable fillers in the field of plastic surgery [1237,1296]. The application of HA for penile girth enhancement has recently gained increasing popularity due to its biocompatibility and infrequent mild temporary side effects. The newly invented cross-linked HA has a more lasting effect over time [1297]. Hyaluronic acid has been used for patients for penile girth enhancement. Studies have reported that an increase of 1.4 to 3.78 cm in penile girth is achieved with HA injection (Table 31). Patient satisfaction is high (78-100%) and no severe side effects have been reported [704,1298-1301].

Table 31: Published data on evaluation of Hyaluronic acid injection therapy on penile girth enhancement

Measurements are expressed as median/mean, (IQR)/±SD.

Polymethylmethacrylate (PMMA)

Polymethylmethacrylate (PMMA) microspheres have been injected as a wrinkle filler. An average increase in penile circumference of 3.5 cm was reported in two studies using PMMA for penile girth enhancement [1304,1305]. The authors reported that post-operative swelling and inflammatory reaction resolved within a few days and no pattern of PMMA microspheres migration to neighbouring regions was seen.

Poly-l-lactic acid

Poly-l-lactic acid (PLA) is another widely used soft tissue filler. Poly-l-lactic acid has enhanced effects by stimulating fibroblast proliferation and increasing collagen deposition in tissue. An average increase of 1.2 to 2.4 cm has been reported in the penile girth with PLA injection. No complications other than temporary local pain and swelling were reported in the treated patients [1298,1306].

9.3.2.4.2.2. Other Fillers (silicone, paraffin)

Foreign body injections are still frequently practised in many countries (especially in East Asia and East Europe), either by the patient himself or by healthcare workers, using various substances such as paraffin, silicone or petroleum jelly (Vaseline), to increase the circumference of the penis [1307]. This results in a chronic granulomatous inflammatory foreign body reaction [1307,1308]. The result of this practice is a pathological condition called sclerosing lipogranuloma of the penis also referred as paraffinoma or siliconoma according to the substance used [1307]. The resultant inflammatory process ranges from oedema and infection to Fournier’s gangrene. Penile reconstructive surgeries may be required when siliconoma and paraffinoma require excision [1307-1313].

9.3.2.4.3. Surgical therapy

9.3.2.4.3.1. Autologous fat injection

This is a surgical technique based on thinning the lower abdomen with liposuction and injecting the harvested fat tissue into the penile shaft [1314-1317]. In retrospective studies, an average increase of 2 to 3.5 cm in penile circumference was reported in patients who underwent autologous fat injection. No statistically significant decrease was observed in IIEF scores and no serious adverse events, such as penile abscess or deformity requiring reoperation occurred. Post-operative satisfaction survey showed that more than 75% of patients were satisfied (Table 32) [1280,1314,1315,1318].

Table 32: Published data on the evaluation of autologous fat injection on penile girth enhancement

Measurements are expressed as median/mean, (IQR)/±SD.

9.3.2.4.3.2. Grafting procedures (albugineal and peri-cavernosal)

Until more rigorous multi-institutional studies reporting on complications and validated outcomes are known, penile girth enhancement procedures using grafts should be considered experimental (Table 33).

In a study of 69 patients using the porcine dermal acellular matrix graft (InteXen; American Medical Systems, Minnetonka, MN, USA) a 3.2 cm increase in flaccid state and 2.4 cm in erect state was reported at one year following surgery. The procedure was performed with an infrapubic incision, and 68 of 69 patients reported significant satisfaction using the Augmentation Phalloplasty Patient Selection and Satisfaction Inventory. Graft fibrosis has been observed in up to 13% of patients, and a mean reduction in penile length of 0.5 cm has been reported in patients with fibrosis [1319].

Techniques using venous grafts for penile girth enhancement have also been described [1320]. Initial results are encouraging, but better designed RCTs are needed.

Dermal fat grafts are free only grafts composed of deepithelialized dermis and subcutaneous fat. An area of approximately 10 x 5 cm is required for graft harvesting. An increase in penile girth of 1.67 to 2.3 cm has been reported in studies with the dermal fat graft technique. Penile oedema up to 27%, painful erection up to 27%, and curvature due to graft fibrosis up to 9% have been reported. Side effects such as penile hypoesthesia, skin necrosis, and infection were not reported [1250,1321,1322].

Table 33: Published data on evaluation of grafting techniques on penile girth enhancement

9.3.2.4.3.3. Biodegradable scaffolds

This is a technique based on using fibroblasts (harvested from patients’ own scrotum skin and dartos tissue) in tissue cultures and seeding them in microporous biodegradable poly-lacti-co-glycolic acid (PLGA) scaffolds and implanting these scaffolds between Dartos and Buck’s fascia. A limited number of studies have reported girth gain of up to 4.02 cm with implantation of biodegradable scaffolds [1326-1328] (Table 34).

Table 34: Published data on the evaluation of implantation of biodegradable scaffolds

9.3.2.4.3.4. Subcutaneous penile implant (Penuma®)

Recently, a silicone penile implant called “Penuma^®” (International Medical Devices [Beverly Hills, CA, USA]) has been approved and has shown promising results for penile girth enhancement. Penuma^® is a soft silicone subcutaneous implant placed on 3/4 of the penile shaft and fixed to the glans with a polyester mesh [1323]. Studies have reported an average increase in penile circumference of 2 to 5 cm with Penuma^® insertion. According to published data complication rates (usually mild and transient, occur in <5%) and the removal rate (1%) of the implant has been reported to be relatively low [1323,1329].

9.3.2.4.4. Summary of evidence and recommendations for penile girth enhancement

Figure 11: Management of short penile size* Penile length should be measured stretched both from the penopubic skin junction-to-glans tip (STT) and from the pubic bone-to-glans tip (BTT).
# There is a lack of evidence to recommend one treatment over another. 
**Hyaluronic acid (HA), poly-l-lactic acid (PLA), hydroxyethyl methacrylate, polymethylmethacrylate (PMMA), polyacrylamide hydrogel (PAAG) and calcium hydroxyapatite are considered as injectable materials for penile girth enhancement. Although the level of evidence is low, there is more evidence for HA, PLA and PMMA. Do not use silicone, paraffin or Vaseline (Strong evidence against).
The strength of recommendations is depicted between brackets where appropriate.

9.3.2.5. Functional outcomes: sexual function, sensitivity, impact on quality of life and emotional adjustment

Cosmetic treatments, including surgery, help to restore self-esteem, reduce anxiety, social phobia, and depressive mood states regarding body concerns, and increase individuals’ well-being and QoL [1123,1124]. Therefore, we can expect men with genuine short penis to use available resources to adjust the length or girth of their penis as a mean to improve their sense of identity and fit cultural standards regarding penile size and function. Currently, the results of penile augmentation techniques seem mixed. The utilization of fillers led to enhanced genital self-image and self-esteem, as well as reduced symptoms of PDD. However, no effects were observed in terms of self-confidence or satisfaction with sexual relationship [1257]. Likewise, penile lengthening or girth enhancement surgery seem to result in poor satisfaction, poor erectile function and sensitivity in men with normal penis size [1134]. Despite those negative outcomes, cases of increased satisfaction have been registered [1330]. Male genital self-image has been related to IIEF domains: sexual desire, orgasmic and erectile function, intercourse and overall satisfaction [1247]. Similarly, perceived penis size seems to predict erectile function more than objective size [1130]. In addition, reduced penetrative and receptive oral sex is associated with men’s dissatisfaction regarding their penis [1331]. For these reasons, more efforts should be made in order to clarify the impact of penile augmentation treatments on men’s and partners’ well-being and QoL. As for men with BDD, they have shown reduced erectile and orgasmic function, as well as less intercourse satisfaction as compared with controls, while men with SPA revealed reduced satisfaction. Sexual desire seemed untouched in BDD and SPA cases [1257,1332].

9.3.2.6. Final remarks

The complaint of “short penis” is variable in presentation and aetiology. Some patients demonstrate anatomical and pathological conditions while others do not. A vast array of treatments for different aetiologies of “short penis,” both surgical and non-surgical, have been reviewed. If psychopathological symptoms are detected, the patient must be referred for further medical diagnosis. Treatment for short-penis syndrome requires a multi-disciplinary approach, including medical and ethical considerations, and the majority of reported outcomes are based on a paucity of evidence.