Osmotic Expanders Research Articles

Clinical evaluation of soft tissue dimension increase by use of osmotic expanders in guided bone regeneration procedures

Clinical evaluation of soft tissue dimension increase by use of osmotic expanders in guided bone regeneration procedures

Second-generation self-inflating tissue expanders: a new dimension in tissue expansion

Objective To study the different uses of second-generation self-inflating tissue expanders regarding the advantages, disadvantages, and the rate of complications. Background Tissue expansion is a valuable technique in soft-tissue reconstruction. Osmotic expanders are self-inflating and obviate the need for repeated injections. They eliminate port-site problems and reduce the potential to introduce infection. The use of such expanders has become more common in recent years. Patients and methods The study included two parts: retrospective part from January to June 2017 and prospective part from August 2017 till January 2019. The study included 40 patients, admitted to the Plastic Surgery at El-Menoufyia University Hospital and Prince Mohammad Bin Abdulaziz National Guard Hospital – Madinah in Saudi Arabia. The patients had post-burn scars, alopecia, and large nevi. A total of 69 second-generation self-inflating tissue expanders were implanted from January 2017 till January 2019, with a follow-up period of 12 months. Results Of the patients, 30 patients were females and 10 were males. The indication was large scar in 30 cases, alopecia in five cases, and giant nevus in five cases. Extrusion occurred in 10 (14.4%) expanders, which occurred in six (15%) patients. The highest percentage of extrusion occurred in the scalp, in which six of 10 expanders extruded. Conclusion The study indicates that self-inflating expanders can be safely and effectively used for various plastic and reconstructive procedures especially in children. The fact that numerous painful and distressing filling sessions are obviated with these expanders is particularly beneficial for those children too young to understand and cooperate. Moreover, this approach minimizes the risk of infection and lowers costs.

Intraoperative Pulsed Expansion of the Skin Using Silicone Urinary Catheter for the Placement of Osmotic Expander.

Intraoperative Pulsed Expansion of the Skin Using Silicone Urinary Catheter for the Placement of Osmotic Expander.

Giant Congenital Melonocytic Nevi of Face-Primary Excision with Reconstruction Using Self-Filling Osmotic Expanders.

Congenital hairy nevi or giant congenital melanocytic nevi (GCMN) especially that of the face pose a great challenge to reconstructive surgeons. These unsightly lesions can be psychologically damaging to both parent and child. A variety of treatment options exist for the management of such cases. In this review article, we present two children who had a GCMN of their face managed with self-inflatable tissue expanders (osmotic tissue expanders [OTEs]) for single stage excision, and reconstruction is presented. The uses of self-inflating tissue expanders are now a regular choice for tissue cover in wide areas and in children.

Worldwide enucleation techniques and materials for treatment of retinoblastoma: an international survey.

PurposeTo investigate the current practice of enucleation with or without orbital implant for retinoblastoma in countries across the world.MethodsA digital survey identifying operation techniques and material used for orbital implants after enucleation in patients with retinoblastoma.ResultsWe received a response of 58 surgeons in 32 different countries. A primary artificial implant is routinely inserted by 42 (72.4%) surgeons. Ten (17.2%) surgeons leave the socket empty, three (5.2%) decide per case. Other surgeons insert a dermis fat graft as a standard primary implant (n=1), or fill the socket in a standard secondary procedure (n=2; one uses dermis fat grafts and one artificial implants). The choice for porous implants was more frequent than for non-porous implants: 27 (58.7%) and 15 (32.6%), respectively. Both porous and non-porous implant types are used by 4 (8.7%) surgeons. Twenty-five surgeons (54.3%) insert bare implants, 11 (23.9%) use separate wrappings, eight (17.4%) use implants with prefab wrapping and two insert implants with and without wrapping depending on type of implant. Attachment of the muscles to the wrapping or implant (at various locations) is done by 31 (53.4%) surgeons. Eleven (19.0%) use a myoconjunctival technique, nine (15.5%) suture the muscles to each other and seven (12.1%) do not reattach the muscles. Measures to improve volume are implant exchange at an older age (n=4), the use of Restylane SQ (n=1) and osmotic expanders (n=1). Pegging is done by two surgeons.ConclusionNo (worldwide) consensus exists about the use of material and techniques for enucleation for the treatment of retinoblastoma. Considerations for the use of different techniques are discussed.

Reconstruction of acne keloidalis nuchae using osmotic tissue expanders—a case series

Background Acne keloidalis nuchae (AKN) is a benign condition of keloid-like papules on the occipital scalp area. Treatment for AKN is divided into conservative and surgical. The use of tissue expander enables preservation of the hirsute area and thereby achieves a good cosmetic result. Osmotic tissue expander is a self-filling device, which absorbs tissue fluids in order to increase skin volume gradually. So far, the use of osmotic expander for reconstruction of AKN has not been described. We present our experience with five consecutive cases of tissue reconstruction using osmotic expanders in AKN.

Therapiemöglichkeiten bei funktionslosem Mikrophthalmus und klinischem Anophthalmus

Children suffering from congenital anophthalmos (absence of eyes) or blind microphthalmos (eyes too small without light perception) show significant smaller eyelids, conjunctival sacs and orbital volume due to the lack of intrauterine growth stimulus. Highly hydrophilic osmotic expanders allow prostheses to be fitted in the first year of life to compensate for the volume deficit and the substantial aesthetic disadvantages and to stimulate lid development.

Efficacy of reconstruction for congenital microphthalmos

To investigate the therapeutic procedures and their efficiencies for the treatment of congenital microphthalmos during or after the developing period. It was a retrospective case series study. Eighteen cases with congenital microphthalmos, aged less than 12 years, underwent self inflating osmotic hydrogel expanders. Among them, 11 cases were treated by implantation with sphere self-inflating hydrogel expanders into the retrobulbar space and 5 cases had implantations into the conjunctival socket. The remaining 2 cases were treated with implantation of injectable self-inflating hydrogel pellet expanders. Twenty eight cases with congenital microphthalmos, aged more than 12 years, accompanied with other deformities, were treated with proper reconstruction surgery. Fourteen cases were treated with medial canthoplasty, 12 cases were treated with medial and lateral canthoplasty, 3 cases were treated with ptosis correction and medial or lateral canthoplasty and 2 cases with socket reconstruction. T-test was used for the comparison between groups. Sixteen cases obtained satisfactory results without any complications. In one case, the hydrogel expanders migrated inferiorly in the orbit and underwent adjustment. In another case, although the hydrogel expander prolapsed from the socket, the socket was still expanded. In the developing period, the length of palpebral fissure was (15.83 ± 1.87) mm before the operation, and that made much wider after the operation (18.67 ± 1.74) mm. There were statistically significant differences between them (t = -4.029, P = 0.01). The height of palpebral fissure was (1.33 ± 0.67) mm and (6.00 ± 0.58) mm before and after the operation, respectively, which were statistically significant (t = -5.813, P = 0.00). Patients who aged more than 12 years and underwent eyelids and eye socket reconstruction, also obtained satisfactory appearance. Patients with congenital microphthalmos could obtain the development of orbit and satisfactory appearance by reconstruction treatment according to different period of development.

Biomechanical effect of rapid mucoperiosteal palatal tissue expansion with the use of osmotic expanders

The comparative study was performed to investigate the biomechanical properties (maximum tangential stiffness, maximum tangential modulus and tensile strength) of expanded mucoperiosteal palatal tissue after rapid expansion regimen correlated with histological findings. Rabbit palatal model was used to correlate the non-operated control group, sham-operated control (subperiosteal tissue dissection) groups and 24- and 48-hour tissue expansion groups. There was no observed damage of tissue collagen network in both tissue expansion groups analyzed immediately after expansion, and biomechanical profile was not significantly different from the profile of control groups. However, rapid tissue expansion activates remodeling of mucoperiosteal tissue structure that revealed significant changes in mechanical properties during the 4-week follow-up. The 24-hour expansion induced transient increase of resilience observed 2 weeks after surgery in comparison to the control groups. As a result of maturation of newly created collagen fibers and mucoperiosteum rebuilding, there were no significant differences between any of the analyzed tensile parameters 4 weeks after the 24-hour expansion. Increased and elongated inflammatory response and connective matrix synthesis observed during healing of 48-hour expanded tissue led to a significant decrease of tensile strength value in comparison to the control groups. Even though 4 weeks after surgery, the resilience of 48-hour expanded tissue was similar to the control groups, tissue healing was not completed and limited scar formation might considerably change the final biomechanical tissue profile. These findings provide new information about tensile properties to rapid mucoperiosteal palatal tissue expansion with the use of osmotic expanders for cleft palate repair by tissue augmentation.

Composite Implants in Oculoplastic Surgery

Composite devices containing two or more different material components or phases are seen with increasing frequency in oculoplastic, orbital, and lacrimal surgery. These combinations aim to improve mechanical and biological properties such as expansion, malleability, and strength in ways that have not been achieved with solitary material designs. Herein we review a variety of these new generation implants, including distensible orbital tissue expanders, hydrophilic osmotic expanders, titanium and polyethylene rigid fixation devices, non-expandable hydrogels, laminated porcine intestine, and polyethylene-coated glass that likely herald a trend to more complex implantable devices in the future.

A New Technique of Expanding the Underdeveloped Scrotum

Sir: Absence of testis often leads to underdevelopment of the scrotum. Tissue expanders1 stretch the underdeveloped scrotum to accommodate a testicular prosthesis. Disadvantages are the need for a second operation, the use of an implant with the risk of infection, the inflation time, repeated visits, and punctures to inflate the expander. A self-inflatable device overcomes these disadvantages. In 1982,2 a self-inflating model was introduced based on a silicone balloon filled with a hyperosmotic fluid, later replaced by hydrogel in 2000,3 commercialized as the OSMED expander (OSMED GmbH, Hartheim, Germany). The expander absorbs body fluids, leading to gradual swelling, providing a predetermined volume and size. The use of an osmotic expander for this indication has never been described before. A 17-year-old boy with bilateral cryptorchidism was treated earlier with bilateral orchidopexy and later with orchidectomy on the right side and scrotal fixation on the left side. The left testis atrophied. Placement of a testicular prosthesis failed. At examination, the testicular implant was fixed in the right inguinal region, with an underdeveloped scrotum without palpable testis (Fig. 1).Fig. 1.: Preoperative situation: migrated testicular prosthesis on the right side and shriveled underdeveloped empty scrotum.A large pocket was created under general anesthesia by an incision high on the scrotal sac. The OSMED rectangular expander with a final volume of 200 ml was inserted. The pocket was closed using a purse-string suture to prevent migration. Drains were not used. The migrated testicular prosthesis was removed. The patient was discharged to home on the first postoperative day. No infection or wound dehiscence, discomfort, or pain was observed at follow-up. Maximum expansion was achieved after 4 weeks, with explantation after 40 days. Two 5-cm testicular implants were fixed at the bottom of the pouch. A 4-month follow-up showed no adverse effects, with a satisfactory result (Fig. 2).Fig. 2.: Satisfactory result after 4 months.By expanding the scrotal tissue, additional scarring from multiple procedures in the past was overcome, providing adequate scrotal soft-tissue coverage. Tissue expansion does not alter the contractility or expansion of the scrotal wall in response to ejaculation, cold, or warmth. Disadvantages of traditional expanders are implant leakage, because of the great mobility of the scrotum, and the need for fillings, risking iatrogenic infections.4 The position of the valve can be troublesome because of the great mobility and limited space. Osmotic expanders overcome many of these disadvantages. The small size of the device reduces operative time, requiring a short incision.5 The final volume of the osmotic expander is defined accurately, facilitating surgical planning. The inflation process is uncontrollable, which can be troublesome in causing, for example, skin ischemia or pain. In our patient, the inflation progress was gradual, without pain or discomfort even at full expansion. At 4-month follow-up, no adverse effects were observed. The testicular prosthesis did not migrate or override and had an aesthetically pleasing result. Scrotal tissues responded well with contraction to cold and relaxation after warm stimuli. In conclusion, we can say that the use of an osmotic expander for expanding the underdeveloped scrotum is a safe, reliable, and easy technique that brings important advantages over the use of traditional expanders. DISCLOSURE The authors have no financial interest to declare in relation to the content of this article. Gregory P. A. Van Eeckhout, M.D. Bert Vanmierlo, M.D. Marc Kioe A. Sen, M.D. Paul Wylock, M.D. Department of Plastic, Reconstructive, and Aesthetic Surgery Johan Braeckman, M.D. Department of Urology Universitair Ziekenhuis Brussel Brussels, Belgium

The osmotic tissue expander: A 5-year experience

Tissue expansion is a valuable technique in soft tissue reconstruction. Osmotic expanders are self-inflating and obviate the need for repeated injections. In doing so, they eliminate port site problems and may reduce the potential to introduce infection. The use of such expanders has become more common in recent years. We report on our experience with the Osmed™ osmotic expanders over the last 5-years.

Reconstruction of a large scalp defect by the sequential use of dermal substitute, self-filling osmotic tissue expander and rotational flap

Large scalp defects pose a challenge for the surgeon. Here, we present a 31-year-old male patient with a soft tissue defect on the temple with exposed bone. To allow reconstruction, we placed a self-filling osmotic expander in the subgaleal pocket for 12 weeks. The final volume of the tissue expander was 300 mL. In the last step, a rotational flap was created after removal of the tissue expander from its pocket. Thereby, a tension-free suturing was possible. The post-surgical healing was uncomplicated. Osmotic tissue expanders are a valuable tool for the closure of large tissue defects without the necessity of repeated filling procedures.

Periosteal expansion of rabbit mandible with an osmotic self-inflatable expander

We aimed to evaluate a new technique for intraoral expansion of soft tissue with a self-inflatable expander in rabbits. We placed a self-inflatable soft tissue expander bilaterally in eight rabbits under the periosteum of the mandible through an extraoral approach. The expander was left to self-inflate for two weeks, after which the animals were killed and specimens collected for histological examination. The self-inflatable soft tissue expanders expanded the periosteum. There were no dehiscences or infections. Histological observations showed no signs of any inflammatory reaction and there was no evidence of bony resorption. New bone had formed at the edges of the expanded periosteum. In the control area no new bone had formed. The osmotic soft tissue expander model for intraoral soft tissue and periosteal expansion suggests a promising way of creating a surplus of soft tissue that can be used to cover bone grafts.

The osmotic tissue expander: a three-year clinical experience

Closure of defects after trauma or excision of neoplasms is a basic skill in plastic surgery. Local, regional and distant flaps lead to additional scars. Skin recruitment by serial excision or skin expansion is a less damaging option for defects that must be closed. Advantages of tissue expansion include good colour and texture match. Disadvantages are the need for a second operation, use of an implant with the attendant risk of infection, time needed for inflation of the device, repeat visits to the clinic, and punctures to inflate the expander. To overcome the last disadvantage, an osmotic expander was developed in Germany in 1999 by OSMED GmbH (Ilmenau).

Investigation of the Expansion Properties of Osmotic Expanders with and without Silicone Shell in Animals

Particularly in clinical studies, it has been found that rapid swelling of tissue expanders leads to high-pressure peaks that can cause hypoxia in the tissue and thus also skin damage. For this reason, the present study in animals investigated whether an osmotic expander with silicone shell is capable of expanding in tissue and bringing about useful tissue expansion without complications. It was also examined whether and what quantitative and qualitative differences there are between conventional osmotic expanders and the new expanders with silicone shell. The expansion of osmotic expanders with silicone shell was compared with that of osmotic expanders without silicone shell in four mini pigs. The expander type used was an M1 rectangle with an initial volume of 6 ml. Five expanders were implanted in each pig, meaning that 20 expanders were measured. The volume of the expanders was measured directly after explantation. Indirect volume determination was performed by producing plaster casts for subsequent laser optical measurement. Comparison of the two curve profiles showed a much flatter profile for the expanders with silicone shell. The absolute values for the volumes of the expanders with silicone shell were likewise substantially lower. Controlled skin expansion is a technique of providing localized donor tissue for reconstructive surgery. The new expanders could be in a position to lower the rate of complications in tissue expansion.

Cleft palate repair with the use of osmotic expanders: a preliminary report

A new method of cleft palate repair by expansion of tissue by means of osmotic expanders implanted in the first stage of treatment is described. Self-expanding expanders manufactured by OSMED (Ilmenau, Germany) were implanted under the mucoperiosteal layer of the hard palate, on purpose to generate more tissue and provide facility for palate repair performed 24-48h later. Nineteen children aged from 2 to 3 years were operated from January 2004 to 15 April 2005. In clefts<10mm, tissue repair was possible without relaxing incisions. In 11 patients with clefts>10mm, cleft palate repair was more difficult and the outcomes were less favourable. Despite more generous dissection of the neurovascular bundles and other adjunctive measures such as mucosal V-Y plasty [Bardach J, Salyer K. Surgical techniques in cleft lip and palate. Chicago, London: Year Book Medical Publishers, Inc.; 1987.] and suturing of the mucosal grafts at the border of the hard and soft palate, seven 2-4mm fistulae were noted, however. Concluding, in spite of some shortcomings and unacceptable rate of fistula in wide clefts, the above-presented method seems to be an attractive concept. Despite some technical problems related mostly to still tested optimal filling phase, tissue expansion makes palate repair easier, probably without relaxing incisions and bone denudation. Consequently, some adverse effects on facial growth may be reduced. So far, there is no evidence for it, however, and since this is a preliminary report, there is a need for longer observations and larger material.

Expansion of the Socket and Orbit for Congenital Clinical Anophthalmia

Congenital clinical anophthalmia requires fitting an artificial eye, achieving a pleasing aspect of the palpebral apparatus, and stimulating growth of the orbit, as well as of the entire midface. Out of 25 patients with clinical anophthalmia, 22 were treated according to a new protocol (first described by Wiese et al. in 1999) and followed for up to 6 years. In 10 patients, anophthalmia was bilateral, in nine patients, it was on the right side only and in three it was on the left side only. Treatment consisted of implantation of an osmotic expander to first stimulate growth of the conjunctival sac and eyelids followed by serial implantation of osmotic expanders to stimulate growth of the orbit (and thus of the midface). The material used was a copolymer of methylmethacrylate and N-vinylpyrrolidone. Fitting of an artificial eye was without any problem within the first year of life for the most part. Growth of the orbit was stimulated by more than 65 percent of a healthy one. Aesthetically, the results were very largely pleasing. Complications were encountered, especially when the wrong expander sizes had been implanted. Using osmotic expanders of this type, through a staged therapy of minor operations, promises to achieve all goals before the child enters school.

Use of self-expanding, hydrophilic osmotic expanders (hydrogel) in the reconstruction of congenital clinical anophthalmos

Rehabilitation of the congenitally anophthalmic orbit is frustrating to both the parents and physician. Traditional methods involve using progressively enlarging static acrylic conformers to expand the conjunctival socket, followed by placement of conventional static spherical orbital implants, dermis-fat grafts, or inflatable balloon expanders for orbital enlargement. Limitations of these methods typically result in less-than-optimal cosmetic outcomes, with retardation of bony orbital and overlying soft tissue growth adversely affecting midfacial growth and symmetry. Recent advances in tissue expansion technology may offer additional, novel alternatives to conventional therapies. Hydrogel tissue expanders were recently adapted for use in congenital anophthalmia. The expanders are placed in their dry, contracted states, and expand gradually to their full size via osmosis of surrounding tissue fluid, with up to a 10-fold increase in volume. Offering the benefit of predictable and controllable self-expansion, hydrogel expanders may offer yet another alternative or adjunctive therapy to the early rehabilitation of the contracted socket. Separate appliances are used for conjunctival and orbital reconstruction. Initial results appear promising. Tempering the enthusiasm for their use, however-particularly in terms of implanted orbital expanders-is the recent spate of long-term complications reported from previous uses of hydrogels as scleral buckling material. Self-expanding hydrogel tissue expanders appear to offer an intriguing reconstructive alternative to the frustrating condition of congenital anophthalmia. Long-term safety of the material as an orbital implant has not yet been demonstrated, but early results are promising.

Is Laser Therapy an Adequate Treatment for Giant Congenital Melanocytic Nevi?

Summary Treatment of congenital and acquired nevi nevocellulares is still controversial because of the possibility of incomplete destruction of deeper situated nevi cells and the possibility of masking a melanoma. Giant congenital melanocytic nevi (GCMN) are rare disfiguring potentially malignant lesions. The approach towards these patients is based on two main considerations: attempt to minimize the risk of malignancy, and obtain an acceptable cosmetic result. Sometimes they are too large to be removed by multiple surgical excision or by use of osmotic expander. The objective of the treatment of giant congenital nevi is to obtain ablation without side effects and aesthetic after-effects. At this time, however, such treatment does not exist. Treatment of GCMN with laser is not an alternative to surgery. Lasers should only be regarded as a treatment option for GCMN that cannot be surgically excised. For the moment laser therapy of GCMN should be restricted to well controlled studies or to individual patients in whom surgical procedure is not possible or where unacceptable scarring would otherwise result. Today ultrashort high energy pulsed CO2 laser and the normal mode ruby laser are the two lasers available. But their results are too unforeseeable, and painful. The combined use of different lasers cannot give us a better solution. In the future new picosecond Q-switched laser can perhaps provide us with another form of treatment, with less pain, and no scars.