HI ALL, Havent share some info in a while, stumbled onto this, it\'s wordy but a good read for anyone considering PMMA, has some cool long term information.
Tolerability and Efficacy of Newly Developed Penile Injection of Cross-linked Dextran and Polymethylmethacrylate Mixture on Penile Enhancement
AbstractCross-linked dextran and polymethylmethacrylate mixture (Lipen-10) is newly developed tissue filler. The purpose of this study was to evaluate tolerability and efficacy of Lipen-10 on penile enhancement. Twenty adult males were included in this study. Lipen-10 was injected into the subcutaneous tissue of the penile shaft. The penile girth and length were measured in the flaccid state, before and 1, 3 and 6 months after the injection. The circumference increased by 3.7'1.2 cm (50.8%, P<0.0001) at penile base, 4.2'0.9 cm (59.0%, P<0.001) at mid-shaft, and 3.8'1.0 cm (53.2%, P<0.0001) at distal shaft and the length increased by 2.3'1.4 cm (63.2%, P<0.001). There was, however, no significant difference between 3 and 6 months post-treatment in girth and length (P-values: 0.796, 0.498, 0.600 and 0.084 for penile base, mid- and distal-shaft and length, respectively). The complications were only one mild asymmetry of penile shape and one 5-mm-sized nodule in the injected site. There were no clinically significant adverse events in all subjects. Penile injection of Lipen-10 led to a significant increase in penile size, showed a good durability and was well-tolerated, without serious adverse events. These results suggest that penile injection of Lipen-10 may be a new effective method for penile enhancement.IntroductionPenis size has been a source of anxiety for men throughout history, and men often feel the need to enlarge their penises in order either to improve their self-esteem or to satisfy and impress their partners. A variety of cross-cultural references to penile enhancement exist. However, there have been reported various adverse events such as re-contracture and shortening after suspensory ligament dissection and graft tissue necrosis, as well as donor site scar after dermal fat graft.Currently, as the need for safer, effective and less invasive procedures are increasing, penile enhancement procedures using injectable products are in high demand. There are several types of injection materials for penile enhancement. However, most of them are not approved yet by the professional societies, and are performed in private settings, leading to medico-legal implications and paucity of scientific data. Dextran is a complex with branched glucan, and is generally used as antithrombotic agent or volume expander. It has been recently used as bulking material for the treatment of vesicoureteral reflux. Polymethylmethacrylate (PMMA) consists of 32'120-?m-sized microspheres with smooth surface. The injected PMMA is not absorbable, and its esthetic effects have endured for >10 years.[5,6] In 2006, it was approved for the treatment of nasolabial folds in USA, and has been widely used to fill lines and wrinkles in the face.Cross-linked dextran and PMMA mixture (Lipen-10; Chungwha Medipower Corporation, Seoul, Korea) is newly developed dermal filler for soft-tissue augmentation. Both of these substances have neocollagenetic properties, and are replaced by the body\'s own tissue after dermal injection.[3,6] Cross-linked dextran and PMMA are easy to mix and do not affect each other physicochemically.In this study, we evaluated the efficacy and tolerability of cross-linked dextran and PMMA mixture on penile enhancement during a follow-up period of 6-months after injection.
aterials and MethodsSubjectsAdult male subjects aged 20'70 (mean age; 44.4 years), who wanted penile enhancement, were recruited in this study. Before procedure, all subjects were evaluated on history and physical examination, especially on anatomical features of the genitalia and on psychological details. The subjects signed an informed consent form, after the study design and possible complications of the penile injection were explained. Men with the following conditions were excluded from the study: psychological/psychiatric history, including major depression; congenital or acquired malformation of the penis; previous penile plastic surgery; phimosis; and any chronic major systemic disease, such as cancer or diabetes.Finally, 20 subjects were recruited to this study in two medical institutions, each of them having 10 subjects. Approvals for the study were obtained from the respective Institutional Review Boards of the two institutions (No. 09-113).Injection MaterialThe filler (Lipen-10) is newly developed dermal filler for soft-tissue augmentation, and is a commercially available product approved by the Korean Food and Drug Administration in 2010.Lipen-10 consisted of cross-linked dextran in 75% and PMMA in 15%. Cross-linked dextran and PMMA are microspheres with diameters of 45'120 ?m and 32'120 ?m, respectively. These microspheres (90% by volume) are suspended in hypromellose solution (10% by volume), therefore, there is no physical or chemical interaction between them. Once injected, the smooth, electrically uncharged PMMA microspheres become encapsulated by endogenously derived connective tissue, which prevents migration of the microspheres. The PMMA microspheres resist phagocytosis and are not degraded by enzymatic digestion. Cross-linked dextran, another component of the mixture, is derived from dextran used as volume expander. The positive surface charges of dextran apparently attract macrophages. In turn, the macrophages release TGF-? and interleukins, which stimulate fibroblasts to produce collagen fibers. After extensive resorption, dextran is replaced by the body\'s own tissue.Injection MethodA single surgeon performed the procedure at each institute. The procedures were carried out in an office setting with the patient in the supine position. The penile skin was cleansed with povidone-iodine topical antiseptics, and a penile block was induced by injecting 2 ml 0.2% lidocaine into the penis root.After the anesthesia had taken effect, the filler was injected into the subcutaneous tissue of the penile shaft, between dartos fascia and Buck\'s fascia by the fanning technique using a syringe with 20-gauge needle. The needle was directed posteriorly and laterally, parallel or tangential to the corpus cavernosum, distributing the material as uniformly as possible from the penile root to the distal shaft, by a continuous back and forth movement, while constantly pressing the syringe plunger. Injected material did not cover ventral part of the penis, to avoid urethral injury or compression. During the procedure, the penis was maintained in the stretched state. Mean injected volume was 23.73 ml (range 17'30 ml), and 4'6 needle punctures were performed during the procedure. The injected surface was thoroughly massaged in order to redistribute the filler as uniformly as possible, without leaving palpable nodules.After injection, an elastic penile support bandage was applied, to support uniform fixation of the injected material and to avoid penile edema. The patients were instructed to construct bandage by himself not to compress too tightly, to avoid squeezing the injected material out of the injected place or voiding difficulty.EvaluationBefore injection of the filler, penile girth and length were measured for all subjects. With the penis in the flaccid state, the penile girth was measured without tension, with a caliper at the base, mid-shaft and distal shaft. The penile length was measured from the pubic-penile skin junction to the coronal sulcus of the penis, and did not include the penile glans, while penis was perpendicular to the body without stretching. The prepubic fat pad was pushed to the bone at the maximum. All measurements were performed in supine position at stable environment. These measurements were repeated at 1, 3 and 6 months after penile injection. The primary end-point of this study was increase in penile girth by 2 cm or more in the flaccid state at 6 months post-treatment. Another end point was increase in flaccid penile length by 1 cm or more. Mathematically, if we consider that the penis as a cylinder and that injected materials are not absorbed or migrated, the increase in girth is 1.97 cm after injection of 18 ml of filling materials. The lengthening effect of penile injection is difficult to calculate mathematically, owing to physiologic contraction and relaxation of penis. Therefore, on the basis of previous results from methods using the same principle, such as autologous fat transplantation, the cutoff point for increase of penile length was decided.Changes in the penile girth and length were analyzed at 1, 3 and 6 months post-treatment. The adverse events, defined as an undesirable medical condition that was not observed before penile injection, were evaluated. Differences in the results between institutes were also analyzed for all parameters.Statistics The changes in the penile girth and length were analyzed at 1, 3 and 6 months post-treatment, using the Student\'s t-test and paired t-test. Adverse events were analyzed with McNemar test. Statistical Package for the Social Science version 19.0 (SPSS, Chicago, IL, USA) was used for all statistical assessments. The P-values for changes of penile girth and length before and 6 months after penile injection were one-sided, whereas the other P-values were two-sided. A P<0.005 was considered as statistically significant for all analyses.
ResultsOut of 20 subjects who finished baseline evaluation and injection, one subject dropped out of the study because of the withdrawal of consent. Finally, a total of 19 subjects were analyzed.The fillers were uniformly distributed in appearance at 6 months post-treatment and did not migrate from the injected surface (Figure 1). On magnetic resonance imaging, the fillers were well-circumscribed between Buck\'s fascia and dartos fascia (Figure 2). (Enlarge Image)Figure 1. Representative figure of injection for penile enhancement. Grossly, materials were uniformly distributed, and the penis at 6 months after injection (right) was more larger than before (left). (Enlarge Image)Figure 2. Coronal view of penis on magnetic resonance imaging at 6 months after penile injection. Materials were well-circumscribed between Buck\'s fascia and dartos fascia, and not migrated. Injected materials were shown inside of dotted line. The penile girth at 6 months post-treatment increased by 2 cm or more in all subjects (100%). The mean circumferences of penile base, mid-shaft and distal shaft before treatment and at 6 months post-treatment were 7.2'0.8 and 10.9'1.1 cm with a mean increase of 3.7'1.2 cm (50.8%, P<0.0001), 7.1'0.8 and 11.3'0.9 cm with a mean increase of 4.2'0.9 cm (59.0%, P<0.0001) and 7.1'0.8 and 10.8'1.1 cm with a mean increase of 3.8'1.0 cm (53.2%, P<0.0001), respectively (Figure 3). There were no significant differences in the girth between 3 and 6 months post-treatment (P-value for comparison at penile base=0.796, mid-shaft=0.498 and distal shaft=0.600, Figure 4). (Enlarge Image)Figure 3. Mean Penile sizes before (black color) and 6 months after penile injection (gray color). All P-values were <0.001. Circumf, circumference. (Enlarge Image)Figure 4. Changes of penile size between, before and 6 months after penile injection. There were no significant differences between penile sizes at 3 months after penile injection and that at 6 months (all P-vlaues>0.05). Circumf, circumference. With regard to the penile lengthening, 16 subjects (84.2%) showed increases of 1 cm or more at 6 months after the penile injection. The mean penile length before treatment and at 6 months post-treatment was 3.6'1.8 and 5.8'1.5 cm with a mean increase of 2.3'1.4 cm (63.2%, P<0.0001, Figure 3). When comparing between 3 and 6 months post-treatment, there was no significant difference (P-value=0.084, Figure 4). All subjects experienced mild and transient penile edema after the bandage was unwrapped. However, in almost all subjects, the penile edema spontaneously subsided within 2 weeks, and there was no case of penile edema lasting for 4 weeks. At follow-up of 1 month after the penile injection, one subject presented mild asymmetry of penile shape that was corrected by an additional injection. At 6 months post-treatment, one subject showed a nodule of about 5 mm on the injected site. This nodule was caused in separately injected site not by a cyst or granuloma. Both cases were mild, and resulted from technical mistakes, rather than drug-induced side effects. There were no abnormal texture, firmness or feeling of the penis in all subjects. Any subjects did not complain about problems associated with the penile erection state, such as distortion, loss of length, or restriction of erect penis, during the study period.There were no statistical differences in the results between the two institutes (P-values for penile base, 0.518; mid-shaft, 0.887; distal shaft, 0.821; and penile length, 0.435).
DiscussionMany different types of penile enhancement surgery are performed all over the world, although there are medicolegal issues and paucity of scientific data. Currently, as the need for safer, effective and less-invasive procedures are increasing, penile enhancement procedures using injectable products are in high demand. Injectable soft-tissue substitutes provide an affordable, nonsurgical alternative for correcting contour defects and soft-tissue augmentation. Several penile injection materials have been used for penile enhancement, including autologous fat, silicone, collagen and hyaluronic acid (HA).[6,8'11]The injection of autologous fat was initially thought to be a promising technique. However, during the injection process, a significant number of adipocytes are ruptured or reabsorbed, and probably the final result leaves only 10% of the fat cells intact. Results for autologous fat injections are considered unpredictable, because of the lack of adequate blood supply to the injected fat and because the plane into which the adipocytes are injected has not been determined. Small amount (up to 0.75 ml) of silicone injection has been commonly used for cosmetic purposes, with satisfactory results and relative safety, mainly in cases of soft-tissue augmentation and restoration of damaged skin. However, in order to achieve penile enhancement, larger volumes of silicone, ranging from 100'150 ml, are required. Therefore, the silicone injection has not been recommended, because of the development of severe complications. Some of the complications were related to the large volumes injected, and others were due to drifting and distant migration, swelling, penile distortion and idiosyncratic and late granulomatous reactions.[2,13] In addition, injection of silicone into the penis increases the likelihood of damaging blood vessels and nerves, thereby causing loss of sensation anderectile dysfunction.[14,15] The collagen products were the first injectable fillers used for esthetic improvement, because endogenous collagen functions as the structural base for the skin, providing strength and support. However, the collagen caused rapid degradation, required frequent reinjection and produced infrequent but significant hypersensitivity reactions.Unlike the aforementioned products, cross-linked dextran and PMMA mixture was well-tolerated, did not cause serious adverse events and provided a significant penile enhancement in this study. All of 19 subjects (100%) fulfilled the criteria for primary end point of penile girth enhancement. Interestingly, 16 of 19 subjects (84.2%) fulfilled the criteria for primary end point of penile length enhancement, and the mean increase of flaccid penile length after 6 months was 2.3'1.4 cm (63.2%). There are only few studies showing an increase in penile length after penile injection using any materials One of the hypotheses is the splint effect of cross-linked dextran and PMMA mixture. As the mixture of cross-linked dextran and PMMA is evenly distributed between Buck\'s fascia and dartos fascia, it prevents the physiologic contraction of the penis and leads to the lengthening effect. From the viewpoint of adverse events, cross-linked dextran and PMMA mixture was superior to the aforementioned products. There were only a few mild adverse reactions, possibly caused by technical mistakes during injection, rather than drug-induced side effects.Lipen-10, cross-linked dextran and PMMA mixture, is newly developed dermal filler for soft-tissue augmentation, and is a commercially available product approved by the Korean Food and Drug Administration in 2010. PMMA-based dermal filler was approved in USA in 2006 for the treatment of nasolabial folds.Once injected, the smooth, electrically uncharged PMMA microspheres are encapsulated by endogenously derived connective tissue, preventing migration of the microspheres. The PMMA microspheres resist phagocytosis and are not degraded by enzymatic digestion. Histological studies indicate that each microsphere is encapsulated by a thin layer of collagen, macrophages and fibroblasts by as early as 1 month. Cross-linked dextran, the other component of mixture, is derived from dextran used as a volume expander, and consists of microspheres similar to PMMA. The positive surface charges of dextran apparently attract macrophages. In turn, the macrophages release TGF-? and interleukins, which stimulate fibroblasts to produce collagen fibers. After being extensively reabsorbed, dextran is replaced by the body\'s own tissue.Jang et al.  studied both the bio-safety and the volume-related effect of Lipen-10, as soft tissue filler in the rat model for 13 weeks. During the experimental period, there were no dead rats and scratching behavior which is a most common symptom when rejecting foreign body was observed. The volume of injected mixture was maintained sufficiently. Complete blood count finding indicated that there were no significant differences in the number of inflammatory cells between control and experimental group. In addition, the parameters of hepatic toxicity (aspartate aminotransferase, alanine transaminase, alkaline phosphatase, ?-glutamyl transpeptidase, lactate dehydrogenase), renal toxicity (creatinine, blood urea nitrogen, cholesterol, albumin, phosphorus), and other organ toxicity (calcium, triglyceride, and creatine phosphokinase) using serum biochemical analysis did not show the significant differences between the control and experimental group, suggesting that systemic toxicity was not found. Histopathological findings indicated that the subcutaneous tissue had red color microsphere which capsulated by collagen near the injection site. Furthermore, the infiltration of inflammatory cells was not observed in the injected sites of all experimental groups. They concluded the Lipen-10 could be a safe substance for soft-tissue augmentation maintaining tissue volume. Our prospective study was designed based on their results.Among the different kinds of PMMA-based dermal fillers, Artefill (Artes Medical, San Diego, CA, USA) consisting of PMMA microspheres with 3.5% bovine collagen and 0.3% lidocaine, is well-known and widely used. The safety and effect of this filler was approved in USA in 2006, although there is no study on penile enhancement. However, one of the major drawbacks is its potential for hypersensitivity reactions, because of the presence of bovine collagen. Artefill requires that all subjects undergo appropriate skin testing several weeks in advance of their planned procedure.[5,19,20] Unlike Artefill, the injection mixture used in this study contained cross-linked dextran instead of bovine collagen. Dextran is widely used in the treatment of vesicoureteral reflux, is safe enough to be recommended in children, and allergy test is not needed. HA-based dermal filler is widely used for penile enhancement. From both biocompatibility and immune viewpoints, as HAs are naturally occurring hygroscopic polysaccharides found in the extracellular matrix, they seem to be an ideal filling substance for soft-tissue augmentation. However, the duration of effect for HA-based dermal fillers as a group ranges from 3'12 months, making this class of temporary fillers intermediate in duration of effect, whereas PMMA-bssed dermal fillers are regarded as permanent or semi-permanent fillers. Recently, Lim et al. studied PMMA- and HA-based filler as an injection laryngoplasty material in canine model for 9 months. They reported that both PMMA and HA were safe and relatively durable as fillers for the vocal folds. They also reported that up to 30% of the HA was gradually reabsorbed over time, while the dimension of the augmented region after 9 months was similar to that achieved in the PMMA group after only 1 month. More recently, Jang et al.  studied the volume effect of cross-linked dextran and PMMA mixture (Lipen-10) in the rat model, compared with HA-based dermal filler. At 13 weeks after injection, although the volume of the HA-based filler was significantly decreased, the volume of cross-linked dextran and PMMA mixture was maintained sufficiently.There were a few limitations to this study. First, the duration of follow-up was not enough to confirm the long-term effect of cross-linked dextran and PMMA mixture. A longer term follow-up over a year is needed for the clinical use. Also, there was no control group in this study. Lastly, evaluation of patient satisfaction and partner\'s response should be followed. In conclusion, penile injection of cross-linked dextran and PMMA mixture showed a significant enhancement of penile girth, good durability at 6 months post-treatment, and was well-tolerated, without serious adverse events. Penile injection of cross-linked dextran and PMMA mixture may be a new effective tool for penile enhancement. Long-term follow-up for tolerability and efficacy should be needed to confirm its value in penile enhancement. www.medscape.com/viewarticle/805309_4
Dragon shark out!
This is Lipen-10 Information, not specifically PMMA information (e.g. Metacril, Linnea Safe, Artefill). I will change the title accordingly. There are some ongoing conversations on this subject matter throughout the forum. Thanks for adding some of the information here in the databases.
I posted a link to this article a few days ago:
It seems a few members on this board have had Lipen-10 but it doesn\'t appear to have any advantage over PMMA.
Do a search on: \"lipen\", \"dextran\" etc to find posts.