The success of PD reconstruction is defined by a postoperative penile curvature of less than 20 degrees, preservation of erectile function, and the ability to engage in sexual intercourse [6]. However, reduced penile length and discomfort or pain caused by extensive plaque may present additional functional challenges in PD, requiring specific surgical strategies. Two potential surgical strategies for penile lengthening in severe PD cases include (1) PIG or PEG without PPI implantation and (2) PPI with or without simultaneous TA incision and grafting [4, 8].

Various grafts have been used to close the tunica albuginea defect following plaque incision or partial plaque excision, including autologous grafts, allografts/xenografts (tissue engineering grafts), and synthetic grafts. An ideal graft should be readily available, resistant to infections, promote hemostasis, minimize postoperative contracture, and be cost-effective [10, 16]. Most synthetic grafts have been discarded due to fibrotic tissue reactions, graft contracture, allergic reactions, and an increased risk of infection [5]. Xenografts are preferred because they offer better outcomes, lack donor site morbidity, and require less operating time than autografts [16]. Currently, the small intestine submucosa is one of the most frequently used xenografts in PD surgery [6].

A technique involving partial plaque excision and grafting with collagen fleece coated with tissue sealant (TachoSil; Mycomed; Konstanz, Germany) has been described [15]. The collagen fleece includes a fibrin glue coating, which precludes the need for fixation or suturing and provides a hemostatic effect. Grafting with collagen fleece requires less operating time because fixation is not necessary. However, more extensive incisional techniques to the tunica albuginea, the application of the patch without fixation, and the mobilization of the NVB for PIG/PEG are surgical aspects that might influence the perioperative and postoperative course of the patients. This raises the question of whether the technique should be reserved for cases with curvatures > 60°, given that the usually less invasive plication procedures are recommended for curvatures < 60° by most guidelines.

Our study identified a significant association between DM and severe curvature; the number of patients with DM was significantly higher in the severe curvature subgroup (> 60°). However, both subgroups were similar in terms of age, hospital stay, operative time, early results, and complications. In addition, we found no significant differences in operating time or early postoperative complications between the two subgroups with curvatures > 60° and < 60°, indicating that the technique can be applied with the same risk profile regardless of the degree of deviation.

After performing PEG and CFG in 63 men, Hatzichristodoulou and collaborators reported [15] that 84% achieved complete penile straightening during immediate follow-up in a previous study. The mean dorsal curvature was 67° (ranging from 30° to 100°), with an average operating time of 94 min (ranging from 65 to 165 min). Notably, 17% of these patients experienced a mild residual curvature of less than ten degrees. An analysis of outcomes from 52 PD patients who underwent CFG after PIG/PEG revealed a 92.3% success in achieving complete curvature correction. Furthermore, 80.8% of patients did not experience significant penile shortening after a 6-month follow-up [17]. The efficacy of this technique has been described in patients with dorsal, dorsolateral, or ventral curvatures [13, 15, 17, 18].

Studies on CFG patch grafting have reported penile straightening rates ranging from 83% to 93.7% [13, 15, 19]. In a retrospective study, Horstmann et al. [13] compared 32 patients undergoing plication (Nesbit or Essed‒Schroeder technique) versus 43 patients who underwent CFG. They reported similar perioperative and postoperative complications in both groups. Satisfaction rates did not differ between the study groups. Overall, 21 patients (66%) with plication and 36 patients (84%) with GFG had a straight or almost straight penis postoperatively. However, patients treated with plication reported better outcomes regarding erectile function, penile length, and sensation. Notably, around 60% of patients expressed their willingness to choose the same intervention again.

Compared to the less invasive character of plication techniques for PD, a decrease in penile sensation (penile hypoesthesia, glans numbness) has been reported in 3% to 31% of the cases with PD after surgery, which can lead to sexual dysfunction [5]. The mobilization of the NVB is often attributed to this typically transient decrease in sensation, with complete resolution reported within 12 months post-surgery in up to 100% of cases [6]. In our study, a decrease in penile sensation was noted in 9% of the patients, with no discernible variance between the different surgical subgroups.

The occurrence of postoperative hematoma, bleeding, and infection remained generally low (2–4.5%). However, one patient experienced postoperative glans necrosis. While this complication has not been reported following plication procedures, it has been documented in up to 2.4% of cases after grafting procedures [6]. Another potential advantage of CFG over other xenografts is its presumed reduced risk of postoperative hematoma due to its hemostatic properties [4, 5, 11].

Recently, Falcone and colleagues compared CFG and porcine small intestine submucosa grafts in patients undergoing plaque incision with grafting and penile prosthesis. After a mean follow-up of 35 months, there were no significant differences in postoperative outcomes. However, the use of CFG was associated with significantly shorter mean operating time (128.8 for TachoSil grafting versus 148.8 for SIS, p < 0.0001) and lower costs [20]. The reduced operating time with CFG was linked to a decreased risk of infections [11]. It is important to note that intraoperative assessment of residual penile curvature at maximum erection with intracavernous saline injection is not feasible with CFG due to the risk of graft detachment [4, 17]

Some limitations of the current study need to be acknowledged. The study design was retrospective, thereby constrained by the data routinely collected. Moreover, only early postoperative follow-up assessments were taken into account. Detailed postoperative evaluation of erectile function based on preoperative scores was not documented. The postoperative assessment of erectile function using the IIEF-5 score was not documented for all patients. In addition, patients who received preoperatively PDE5i or intracavernous injections were included, which could introduce confounding factors. The medium-term and long-term outcomes remain undisclosed in our study, potentially revealing significant subgroup disparities in functional outcomes or delayed complications.