Prospective Cohort Study Comparing Ligament Reconstruction with Tendon Interposition and Suture-Only Suspension Arthroplasty.

BACKGROUND: Basal joint arthritis is a common form of osteoarthritis. There is no consensus procedure for maintenance of trapezial height following trapeziectomy. Suture-only suspension arthroplasty (SSA) is a simple method for stabilizing the thumb metacarpal following trapeziectomy. METHODS: This single-institution, prospective, cohort study compares trapeziectomy followed by either ligament reconstruction with tendon interposition (LRTI) or SSA for the treatment of basal joint arthritis. Patients underwent LRTI or SSA from May of 2018 to December of 2019. Visual analogue scale pain scores; Disabilities of the Arm, Shoulder and Hand questionnaire functional scores; clinical thumb range of motion, pinch, and grip strength data; and patient-reported outcomes were recorded and analyzed preoperatively and at 6 weeks and 6 months postoperatively. RESULTS: Total number of study participants was 45 (LRTI, n = 26; SSA, n = 19). Mean ± SE age was 62.4 ± 1.5 years; 71% were female patients; and 51% underwent surgery on the dominant side. Visual analogue scale scores improved for LRTI and SSA ( P < 0.0001) over 6 months, with no differences between groups at any time point ( P > 0.3). Disabilities of the Arm, Shoulder and Hand questionnaire scores improved for LRTI and SSA over 6 months ( P < 0.0001), with no differences between groups at any time point ( P > 0.3). Following SSA, opposition improved ( P = 0.02), but not as well for LRTI ( P = 0.16). Grip and pinch strength decreased following LRTI and SSA at 6 weeks but recovered similarly for both groups over 6 months. Patient-reported outcomes were generally no different between groups at all time points. CONCLUSION: LRTI and SSA are similar procedures following trapeziectomy relative to pain, function, and strength recovery. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Clinical Evaluation of an Off-the-Shelf Allogeneic Adipose Matrix for Soft Tissue Reconstruction.

Biomaterials derived from human adipose extracellular matrix have shown promise in vitro and in animal studies as an off-the-shelf adipogenic matrix for sustained volume replacement. Herein, we report the results of a randomized prospective study conducted with allograft adipose matrix (AAM) grafted into the pannus of presurgical abdominoplasty patients 3 or 6 months before scheduled surgery. This is the first report of a longitudinal histologic analysis of AAM in clinical use. METHODS: Ten healthy patients undergoing elective abdominoplasty were recruited to receive AAM before surgery. Enrolled subjects were randomized into either a 3-month follow-up cohort or a 6-month follow-up cohort. Subjects were monitored for adverse events associated with AAM grafting in addition to undergoing serial biopsy. Following surgical excision of the pannus, representative samples from the AAM surgical sites were stained and evaluated with hematoxylin and eosin for tissue morphology, Masson's trichrome for collagen, and perilipin for adipocytes. RESULTS: All subjects tolerated AAM with no severe adverse events reported. At 3 months following implantation, AAM remained visible within the confines of the subjects' native surrounding adipose tissue with sparse adipocytes apparent within the matrix. By 6 months, AAM had remodeled and was primarily composed of perilipin-positive adipocytes. Histologic analysis confirmed tissue remodeling (hematoxylin and eosin), adipogenesis (perilipin), and angiogenesis (Masson's trichrome) occurred with the presence of AAM. CONCLUSIONS: AAM is a safe, allogeneic, off-the-shelf regenerative matrix that is adipogenic and noninflammatory and promotes angiogenesis.

Long-gap peripheral nerve repair through sustained release of a neurotrophic factor in nonhuman primates.

Severe injuries to peripheral nerves are challenging to repair. Standard-of-care treatment for nerve gaps >2 to 3 centimeters is autografting; however, autografting can result in neuroma formation, loss of sensory function at the donor site, and increased operative time. To address the need for a synthetic nerve conduit to treat large nerve gaps, we investigated a biodegradable poly(caprolactone) (PCL) conduit with embedded double-walled polymeric microspheres encapsulating glial cell line-derived neurotrophic factor (GDNF) capable of providing a sustained release of GDNF for >50 days in a 5-centimeter nerve defect in a rhesus macaque model. The GDNF-eluting conduit (PCL/GDNF) was compared to a median nerve autograft and a PCL conduit containing empty microspheres (PCL/Empty). Functional testing demonstrated similar functional recovery between the PCL/GDNF-treated group (75.64 ± 10.28%) and the autograft-treated group (77.49 ± 19.28%); both groups were statistically improved compared to PCL/Empty-treated group (44.95 ± 26.94%). Nerve conduction velocity 1 year after surgery was increased in the PCL/GDNF-treated macaques (31.41 ± 15.34 meters/second) compared to autograft (25.45 ± 3.96 meters/second) and PCL/Empty (12.60 ± 3.89 meters/second) treatment. Histological analyses included assessment of Schwann cell presence, myelination of axons, nerve fiber density, and g-ratio. PCL/GDNF group exhibited a statistically greater average area occupied by individual Schwann cells at the distal nerve (11.60 ± 33.01 µm2) compared to autograft (4.62 ± 3.99 µm2) and PCL/Empty (4.52 ± 5.16 µm2) treatment groups. This study demonstrates the efficacious bridging of a long peripheral nerve gap in a nonhuman primate model using an acellular, biodegradable nerve conduit.

Pediatric Upper Extremity Replantation: Courage in the Face of a Life-altering Injury.

BACKGROUND: Pediatric plastic surgeons perform reconstructive surgeries for various congenital, oncologic, and traumatic injuries. METHODS: Our Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center (UPMC) Plastic Surgery team was tasked to care for a young man who suffered a proximal humeral amputation of his dominant upper extremity. RESULTS: A multidisciplinary team collaborated throughout his entire acute care and postoperative course, guiding treatment and care in effort to maximize function of his replanted extremity. CONCLUSIONS: This case report details the patient's unique journey and highlights his determination and courage to return back to a normal life.

Delivery of adipose-derived stem cells in poloxamer hydrogel improves peripheral nerve regeneration.

INTRODUCTION: Peripheral nerve damage is associated with high long-term morbidity. Because of beneficial secretome, immunomodulatory effects, and ease of clinical translation, transplantation with adipose-derived stem cells (ASC) represents a promising therapeutic modality. METHODS: Effect of ASC delivery in poloxamer hydrogel was assessed in a rat sciatic nerve model of critical-sized (1.5 cm) peripheral nerve injury. Nerve/muscle unit regeneration was assessed via immunostaining explanted nerve, quantitative polymerase chain reaction (qPCR), and histological analysis of reinnervating gastrocnemius muscle. RESULTS: On the basis of viability data, 10% poloxamer hydrogel was selected for in vivo study. Six weeks after transection and repair, the group treated with poloxamer delivered ASCs demonstrated longest axonal regrowth. The qPCR results indicated that the inclusion of ASCs appeared to result in expression of factors that aid in reinnervating muscle tissue. DISCUSSION: Delivery of ASCs in poloxamer addresses multiple facets of the complexity of nerve/muscle unit regeneration, representing a promising avenue for further study. Muscle Nerve 58: 251-260, 2018.

Decellularized Matrix and Supplemental Fat Grafting Leads to Regeneration following Traumatic Fingertip Amputation.

Decellularized scaffold materials are capable of regenerating missing tissues when utilized under appropriate conditions. Fat grafting also has reported advantages in revitalizing damaged tissue beds. This report details a case of traumatic fingertip amputation treated with a combination of decellularized materials in conjunction with fat grafting, resulting in a supple and functional reconstruction of the affected digit. After traumatic fingertip amputation, a patient was initially treated with decellularized porcine urinary bladder matrix powder. As a second stage, the healed tip scar tissue was reexcised, and a second application of powder was applied. As a third stage, the tip scar tissue was reexcised and a decellularized bilayer was sewn into the soft tissues of the debrided tip, resulting in an improved soft tissue envelope. As a final stage, the restored fingertip soft tissue envelope was fat grafted for additional bulk. Patient underwent treatment every other day with decellularized porcine urinary bladder matrix (powder and bilayer) and was able to reasonably regenerate the traumatic fingertip soft tissue envelope. This resulted in an envelope that was further enhanced with fat grafting. The resulting digit was sensate with maintained length, and possessed a more normal appearance than would be achieved by healing by secondary intention, or local flap or graft coverage. Decellularized materials can be utilized in conjunction with fat grafting to treat traumatic fingertip amputations in select patients. This combination approach is able to achieve a sensate fingertip and regain length lost in the affected digit. Additionally, we describe a novel technique that can be employed to maximize the amount of soft tissue regenerated by the decellularized products.

Simplified Calvarial Reconstruction: Coverage of Bare Skull With GammaGraft Promotes Granulation and Facilitates Skin Grafting.

Repair of scalp defects with exposed calvaria remains a difficult clinical problem. Herein, we present a simple alternative method of scalp reconstruction. Coverage of bare skull with GammaGraft (Promethean LifeSciences, Inc, Pittsburgh, PA) promotes the evolution of granulation tissue and permits subsequent skin grafting without need for burring, drilling, or other manipulation of the outer table of the calvaria. A retrospective review of patients undergoing scalp reconstruction utilizing GammaGraft and subsequent skin grafting was performed at our institution. From our cohort, 5 patients treated with GammaGraft and subsequent skin grafting had both immediate and long-term follow-up available. Indications for scalp reconstruction included erosions of prior skin grafts and direct excision of full-thickness scalp and pericranium. Average time to definitive skin grafting was 3 weeks; repeat application of GammaGraft was required in some patients with reapplication to subsequent smaller wounds as healing occurred. Complications were minor and consisted of ongoing wound drainage. Alternative flap reconstruction was not required in any patient due to treatment failures. No major complications, wound infections, or early reoperations occurred in any of the patients; 1 patient to date has required repeat reconstruction due to recurrent disease. Coverage of bare skull with GammaGraft and subsequent skin grafting provides a simple and elegant solution to an often too difficult clinical problem. Confirmed by results in out limited series, the utilization of GammaGraft in calvarial reconstruction represents an alternative method in surgical care of complex scalp defects with exposed bone.

Clinical Considerations for Vascularized Composite Allotransplantation of the Eye.

Vascularized composite allotransplantation represents a potential shift in approaches to reconstruction of complex defects resulting from congenital differences as well as trauma and other acquired pathology. Given the highly specialized function of the eye and its unique anatomical components, vascularized composite allotransplantation of the eye is an appealing method for restoration, replacement, and reconstruction of the nonfunctioning eye. Herein, we describe conventional treatments for eye restoration and their shortcomings as well as recent research and events that have brought eye transplantation closer to a potential clinical reality. In this article, we outline some potential considerations in patient selection, donor facial tissue procurement, eye tissue implantation, surgical procedure, and potential for functional outcomes.

Diagnosis of Ulnar Nerve Entrapment at the Arcade of Struthers with Electromyography and Ultrasound.

Ulnar neuropathy is caused by compression of the ulnar nerve in the upper extremity, frequently occurring at the level of the elbow or wrist. Rarely, ulnar nerve entrapment may be seen proximal to the elbow. This report details a case of ulnar neuropathy diagnosed and localized to the arcade of Struthers with electromyography (EMG) and ultrasound (US) imaging and confirmed at time of operative release. US imaging and EMG findings were used to preoperatively localize the level of compression in a patient presenting with left ulnar neuropathy. In this case, ulnar entrapment 8 cm proximal to the medial epicondyle was diagnosed. Surgical release was performed and verified the level of entrapment at the arcade of Struthers in the upper arm. Alleviation of symptoms was noted at 8-week follow-up; no complications occurred. US imaging can be used in complement with EMG studies to properly diagnose and localize the level of ulnar nerve entrapment. This facilitates full release of the nerve and may prevent the need for revision surgery.

Ethical Considerations of Whole-Eye Transplantation.

Whole eye transplantation (WET) remains experimental. Long presumed impossible, recent scientific advances regarding WET suggest that it may become a clinical reality. However, the ethical implications of WET as an experimental therapeutic strategy remain largely unexplored. This article evaluates the ethical considerations surrounding WET as an emerging experimental treatment for vision loss. A thorough review of published literature pertaining to WET was performed; ethical issues were identified during review of the articles.

Risk factors for pannus formation in the post-bariatric surgery population.

BACKGROUND: Previous studies describe a relationship between pannus mass and panniculectomy-related complication rates. Patient management may be improved by elucidating the key factors influencing pannus formation. METHODS: A retrospective review was conducted of 135 patients who had undergone laparoscopic Roux-en-Y gastric bypass from 1996 to 2010 and subsequent panniculectomy. Outcome measures included age, sex, body mass index, time of surgery, resected pannus mass, comorbidities, and panniculectomy-related complications. Nonparametric continuous and nominal variables were assessed using Spearman rank-correlation and Mann-Whitney U tests, respectively. RESULTS: One hundred thirty-five patients (123 women and 12 men; mean age, 44.7 years) were included in analysis. All patients had body contouring surgery more than 1 year after bariatric surgery (median time interval, 2.1 years). Median body mass index at the time of bypass, 1 year after bypass, and at the time of body contouring surgery was 48.7, 30.0, and 29.4 kg/m, respectively. Median pannus mass was 2.2 kg. Larger pannus mass was associated with greater age at gastric bypass surgery (p = 0.034), higher pre-gastric bypass body mass index (p = 0.031), higher prepanniculectomy body mass index (p < 0.001), and longer time interval between gastric bypass and panniculectomy (p = 0.046). Female patients requiring blood transfusions had a significantly larger pannus mass than those who did not (p = 0.048). CONCLUSION: Performing bariatric surgery on patients at a younger age or having patients reduce body mass index as much as possible before bariatric surgery may be useful for minimizing symptomatic pannus formation and in turn may decrease rates of panniculectomy-related complications. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Particle size in fat graft retention: A review on the impact of harvesting technique in lipofilling surgical outcomes.

Fat grafting popularity continues to rise among plastic surgeons. As a soft tissue filler, adipose tissue had many desirable attributes: it is easy to obtain, autologous, and may reintegrate into recipient sites. However, fat grafting is clinically plagued by unpredictable resorption rates, thus there is much interest in optimizing the procedure of fat grafting for consistent graft volumes. Fat harvesting, a part of fat transfer surgery, involves the removal of adipose tissue from the donor site. Different harvest procedures, such as whole fat excision or liposuction cannulas, result in a range of fat particle volumes, which may play a role in the cellular stability of grafts. The ideal harvesting technique and fat particle diameter is not currently known. This study aims to review the literature on the impact of fat particle size and clinical fat grafting outcomes, to present overarching conclusions, and to provide future directions for study. Current evidence supports excisional methods and larger bore cannulas to minimize cellular damage, preserve the native architecture, and maximize the number of cells within fat particles.

Management of failed alveolar bone grafts: improved outcomes and decreased morbidity with allograft alone.

BACKGROUND: This study demonstrates the safety and efficacy of allograft alone in revision alveolar bone graft surgery. METHODS: A retrospective review of the authors' institution's alveolar bone graft experience (from 2004 to 2012) with open iliac crest bone graft, minimal-access iliac crest bone graft plus supplemental allograft, and revision allograft alone was performed. All patients (n = 47) were treated with alveolar fistula repair with primary closure. RESULTS: Group 1 patients (12 male, 10 female; average age, 10 years) received iliac crest bone graft alone; 17 had unilateral and five had bilateral clefts. Group 2 (eight male, six female; average age, 9 years) received an iliac crest bone graft plus allograft; six clefts were unilateral and eight were bilateral. Group 3 (six male, five female; average age, 13 years) received revision allograft alone; seven clefts were unilateral and four were bilateral. Average operative time/alveolus was shortest in group 3 compared with groups 1 and 2 (p < 0.0005). Average engraftment was better in group 3 than in group 1 (p < 0.001) and similar to that in group 2 (p < 0.079). Revision alveolar bone graft with allograft alone improved Enemark scores from 3.7 preoperatively to 1.0 postoperatively (p < 0.0001). Hospital stay was shortest in group 3 compared with groups 1 and 2 (p < 0.0001). Bone graft extrusion occurred in six patients (27.3 percent) in group 1, no complications occurred in group 2, and a single necrotic central incisor was lost at the time of revision bone grafting in group 3 (9.1 percent). CONCLUSION: Allograft alone is safe and effective and provides a reliable alternative when traditional alveolar bone graft with iliac crest bone graft has failed. CLINICAL QUESTIONS/LEVEL OF EVIDENCE: Therapeutic, III.

The role of chondroitinase as an adjuvant to peripheral nerve repair.

Chondroitin sulfate proteoglycans (CSPGs) are potent inhibitors of neural regeneration in the peripheral nervous system. Following nerve injury, inhibitory CSPGs accumulate within the endoneurium and Schwann cell basal lamina of the distal nerve stump. The utilization of chondroitinase ABC (chABC) has led to a marked increase in the ability of injured axons to regenerate across gaps through the CSPG-laden extracellular matrix. Experimental models have repeatedly shown chABC to be capable of degrading the CSPGs that hinder neurite outgrowth. In this article, the characterization of CSPGs, their upregulation following peripheral nerve injury, and potential mechanisms behind their growth and inhibition are described. To date, the literature supports that the adjunct use of chABC may be beneficial to peripheral nerve repair in digesting inhibitory CSPGs. chABC has also shown some indication of synergism with other therapies, such as stem cell transplantation. Evidence supporting the use of chondroitinase as a treatment modality in nerve repair, either alone or in combination with other agents, is reviewed within. Finally, several shortcomings of chABC are addressed, notably its thermal stability and physiologic longevity - both hindering its widespread clinical adoption. Future studies are warranted in order to optimize the therapeutic benefits of the chondroitinase enzyme.

Assessing the impact of antibiotic prophylaxis in outpatient elective hand surgery: a single-center, retrospective review of 8,850 cases.

PURPOSE: Prophylactic antibiotics have been shown to prevent surgical site infection (SSI) after some gastrointestinal, orthopedic, and plastic surgical procedures, but their efficacy in clean, elective hand surgery is unclear. Our aims were to assess the efficacy of preoperative antibiotics in preventing SSI after clean, elective hand surgery, and to identify potential risk factors for SSI. METHODS: We queried the database from an outpatient surgical center by Current Procedural Terminology code to identify patients who underwent elective hand surgery. For each medical record, we collected patient demographics and characteristics along with preoperative, intraoperative, and postoperative management details. The primary outcome of this study was SSI, and secondary outcomes were wound dehiscence and suture granuloma. RESULTS: From October 2000 through October 2008, 8,850 patient records met our inclusion criteria. The overall SSI rate was 0.35%, with an average patient follow-up duration of 79 days. The SSI rates did not significantly differ between patients receiving antibiotics (0.54%; 2,755 patients) and those who did not (0.26%; 6,095 patients). Surgical site infection was associated with smoking status, diabetes mellitus, and longer procedure length irrespective of antibiotic use. Subgroup analysis revealed that prophylactic antibiotics did not prevent SSI in male patients, smokers, or diabetics, or for procedure length less than 30 minutes, 30 to 60 minutes, and greater than 60 minutes. CONCLUSIONS: Prophylactic antibiotic administration does not reduce the incidence of SSI after clean, elective hand surgery in an outpatient population. Moreover, subgroup analysis revealed that prophylactic antibiotics did not reduce the frequency of SSI among patients who were found to be at higher risk in this study. We identified 3 factors associated with the development of SSI in our study: diabetes mellitus status, procedure length, and smoking status. Given the potential harmful complications associated with antibiotic use and the lack of evidence that prophylactic antibiotics prevent SSIs, we conclude that antibiotics should not be routinely administered to patients who undergo clean, elective hand surgery. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

Incorporation of ionic ligands accelerates drug release from LDI-glycerol polyurethanes.

This study seeks to determine the effect of ionic ligands on the drug delivery characteristics of biodegradable polyurethane materials synthesized from lysine diisocyanate (LDI) and glycerol. Two naturally occurring, structurally related ionic species, choline chloride (CC) and isethionic acid (ISE), along with 3,3-dimethyl-butanol (DMB), their neutral carbon analog, were covalently incorporated into LDI-glycerol polyurethane materials. Selected organometallic and tertiary amine catalysts were used to fashion films and foams, respectively. The potent anticancer compound DB-67, a fluorescent camptothecin derivative, was also covalently linked to the polyurethane constructs. It was first determined that the sulfonate functional group on ISE does not react to a significant degree with isocyanate. The morphological characteristics of the polyurethane films and foams were assessed via scanning electron microscopy, showing significant differences related to the ionic ligands. The ionic materials displayed increased swelling in aqueous media over the neutral control materials. Differences in the distribution of DB-67 throughout the films and foams were then detected by fluorescence microscopy. The drug delivery characteristics of the materials were then evaluated in vitro, revealing accelerated release from ionic materials. The results of this study demonstrate the unique effects that incorporation of ionic ligands into LDI-glycerol polyurethanes have on the morphology and drug distribution of the materials. These differences have a significant impact on the drug delivery characteristics of the materials, and this information should prove useful in the design and synthesis of biodegradable controlled release systems.

Simultaneous drug release at different rates from biodegradable polyurethane foams.

In this study, we present an approach for the simultaneous release of multiple drug compounds at different rates from single-phase polyurethane foams constructed from lysine diisocyanate (LDI) and glycerol. The anti-cancer compounds DB-67 and doxorubicin were covalently incorporated into polyurethane foams, whereby drug release can then occur in concert with material degradation. To begin, the reactions of DB-67 and doxorubicin with LDI in the presence of a tertiary amine catalyst were monitored with infrared spectroscopy; each compound formed urethane linkages with LDI. Fluorescent spectra of DB-67 and doxorubicin were then recorded in phosphate-buffered saline, pH 7.4 (PBS), to ensure that each anti-cancer compound could be quantitatively detected alone and in combination. Doxorubicin and DB-67 were then incorporated into a series of degradable LDI-glycerol polyurethane foams alone and in combination with one another. The sol content, average porosity and drug distribution throughout each foam sample was measured and found to be similar amongst all foam samples. The stability of DB-67 and doxorubicin's fluorescent signal was then assessed over a 2-week period at 70 degrees C. Release rates of the compounds from the foams were assessed over a 10-week period at 4, 22, 37 and 70 degrees C by way of fluorescence spectroscopy. Release was found to be temperature-dependent, with rates related to the chemical structure of the incorporated drug. This study demonstrates that differential release of covalently bound drugs is possible from simple single-phase, degradable polyurethane foams.

LDI-glycerol polyurethane implants exhibit controlled release of DB-67 and anti-tumor activity in vitro against malignant gliomas.

The purpose of the present study was to develop a biodegradable and biocompatible polyurethane drug delivery system based on lysine diisocyanate (LDI) and glycerol for the controlled release of 7-tert-butyldimethylsilyl-10-hydroxy-camptothecin (DB-67). DB-67 has yet to be implemented in any clinical therapies due to the inability to delivered it in sufficient quantities to impact tumor growth and disease progression. To remedy this, DB-67 was covalently incorporated into our delivery system by way of an organometallic urethane catalyst and was found to be dispersed evenly throughout the LDI-glycerol polyurethane discs. Scanning electron micrographs indicate that the LDI-glycerol discs are uniform and possess a pore distribution typical of the non-solvent casting technique used to prepare them. The release rates of DB-67 from the LDI-glycerol discs were found to vary with both time and temperature and were shown capable of delivering therapeutic concentrations of DB-67 in vitro. Cellular proliferation assays demonstrate that empty LDI-glycerol discs alone do not significantly alter the growth of malignant human glioma cell lines (U87, T98G, LN229 and SG388). DB-67-loaded LDI-glycerol polyurethane discs were found to inhibit cellular proliferation by 50% on average in all the malignant glioma cell lines tested. These results clearly demonstrate the long-term, slow release of DB-67 from LDI-glycerol polyurethane discs and their potential for postoperative intracranial chemotherapy of cancers.

Catalyst-dependent drug loading of LDI-glycerol polyurethane foams leads to differing controlled release profiles.

The purpose of the present study was to develop biodegradable and biocompatible polyurethane foams based on lysine diisocyanate (LDI) and glycerol to be used as drug-delivery systems for the controlled release of 7-tert-butyldimethylsilyl-10-hydroxy-camptothecin (DB-67). The impact of urethane catalysts on cellular proliferation was assessed in an attempt to enhance the biocompatibility of our polyurethane materials. DB-67, a potent camptothecin analog, was then incorporated into LDI-glycerol polyurethane foams with two different amine urethane catalysts: 1,4-diazobicyclo[2.2.2]-octane (DABCO) and 4,4'-(oxydi-2,1-ethane-diyl)bismorpholine (DMDEE). The material morphologies of the polyurethane foams were analyzed via scanning electron microscopy, and DB-67 distribution was assessed by way of fluorescence microscopy. Both foam morphology and drug distribution were found to correlate to the amine catalyst used. Hydrolytic release rates of DB-67 from the polyurethane foams were catalyst dependent and also demonstrated greater drug loads being released at higher temperatures. The foams were capable of delivering therapeutic concentrations of DB-67 in vitro over an 11week test period. Cellular proliferation assays demonstrate that empty LDI-glycerol foams did not significantly alter the growth of malignant human glioma cell lines (P<0.05). DB-67 loaded LDI-glycerol polyurethane foams were found to inhibit cellular proliferation by at least 75% in all the malignant glioma cell lines tested (P<1.0x10(-8)). These results clearly demonstrate the long-term, catalyst-dependent release of DB-67 from LDI-glycerol polyurethane foams, indicating their potential for use in implantable drug-delivery devices.