RESUMEN
While the roots of burn care date back several millennia, recognition and treatment of psychiatric trauma has had a more contemporary journey. Our understanding of burn care has evolved largely separately from our understanding of psychiatry; however, proper care of the burn patient relies on the comprehension of both disciplines. Historically, high burn mortality rates have caused clinicians to focus on the physiological causes of burn mortality. As burn care improved in the 20th century, providers began to focus on the long-term health outcomes of burn patients, including mitigating mental health consequences of trauma. This shift coincided with advances in our understanding of psychological sequelae of trauma. Subsequently, an association between burn trauma and mental illness began to emerge. The current standard of care is the result of thousands of years of evolving practices and theories, yet our understanding of the pathophysiology of depression among survivors of severe burn injury is far from complete. By taking measure of the past, we aim to provide context and evidence for our current standards and emphasize areas for future lines of research.
Asunto(s)
Quemaduras , Trastornos por Estrés Postraumático , Humanos , Depresión/etiología , Depresión/psicología , Quemaduras/complicaciones , Sobrevivientes/psicologíaRESUMEN
Thermal injuries have been a phenomenon intertwined with the human condition since the dawn of our species. Autologous skin translocation, also known as skin grafting, has played an important role in burn wound management and has a rich history of its own. In fact, some of the oldest known medical texts describe ancient methods of skin translocation. In this article, we examine how skin grafting has evolved from its origins of necessity in the ancient world to the well-calibrated tool utilized in modern medicine. The popularity of skin grafting has ebbed and flowed multiple times throughout history, often suppressed for cultural, religious, pseudo-scientific, or anecdotal reasons. It was not until the 1800s, that skin grafting was widely accepted as a safe and effective treatment for wound management, and shortly thereafter for burn injuries. In the nineteenth and twentieth centuries skin grafting advanced considerably, accelerated by exponential medical progress and the occurrence of man-made disasters and global warfare. The introduction of surgical instruments specifically designed for skin grafting gave surgeons more control over the depth and consistency of harvested tissues, vastly improving outcomes. The invention of powered surgical instruments, such as the electric dermatome, reduced technical barriers for many surgeons, allowing the practice of skin grafting to be extended ubiquitously from a small group of technically gifted reconstructive surgeons to nearly all interested sub-specialists. The subsequent development of biologic and synthetic skin substitutes have been spurred onward by the clinical challenges unique to burn care: recurrent graft failure, microbial wound colonization, and limited donor site availability. These improvements have laid the framework for more advanced forms of tissue engineering including micrografts, cultured skin grafts, aerosolized skin cell application, and stem-cell impregnated dermal matrices. In this article, we will explore the convoluted journey that modern skin grafting has taken and potential future directions the procedure may yet go.
Asunto(s)
Quemaduras , Trasplante de Piel , Quemaduras/cirugía , Humanos , Piel , Resultado del Tratamiento , Cicatrización de HeridasRESUMEN
Patients with limited English proficiency (LEP) experience reduced pain assessment and treatment, less comprehensive physical exams, and fewer explanations of the next steps in care. These disparities persist in hospitals with staffed professional interpreters, raising questions about interpreter access and the impact on outcomes. A retrospective review of 1133 trauma activations at a single center Level 1 Trauma Center in 2021-2022 was conducted. Demographic, injury, and outcome data were drawn from the institutional trauma registry, and patient-preferred language was pulled from EMR data. Early interpreter use was defined as documentation of professional interpreter use within 24 h of arrival. LOS and ICU LOS were compared between language groups using Cox regression, and mortality was compared using Fischer's exact test. 1114 patients had data available on initial injury severity and preferred language. Of the 70 LEP patients, 62 (88.6 %) required an interpreter, and 41 of those (66.1 %) had evidence of professional interpreter use within 24 h of arrival. LEP patients who lacked early interpreter use had longer hospital stays than both English proficient (EP) patients (HR 0.59, p < 0.05) and LEP patients with early interpreter use (HR 0.51, p < 0.05) when stratified by ISS and controlling for GCS and patient age. There is no difference in LOS between LEP trauma patients who used an interpreter and EP patients, suggesting that early use of an interpreter may improve the length of stay in LEP trauma patients.
RESUMEN
Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) exist on a spectrum of autoimmune conditions which cause epidermal detachment and keratinocyte necrosis. Due to the rare incidence of these conditions, a dramatic heterogeneity in treatment algorithms exists. To better appreciate pharmacologic immunosuppressive therapies' impact on survival, the authors queried a multi-institutional data network. Data for this study was extracted from TriNetX Research Network, a platform that contains ICD-9/ICD-10 coding data from a consortium of international healthcare organizations. Seventy-one institutions were queried to identify adult patients diagnosed with SJS, TEN or SJS-TEN Overlap. Cohorts were created based on the therapy received: systemic steroids (SS), diphenhydramine (DH), cyclosporine (CS), intravenous immunoglobulin (IVIG), tumor necrosis factor alpha inhibitors (TNFαi), or a combination of treatments. Cohorts were then propensity matched with patients who received supportive care. Patients who only received one of the above treatments showed no significant reduction in 90-day mortality. Patients who received CS or IVIG as part of their multitherapy showed a significantly increased risk of death when compared to supportive care (CS: RR = 1.583, 95% CI [1.119, 2.240]; IVIG: RR = 2.132, 95% CI [1.485, 3.059]). Despite their frequent utilization, this study's analysis suggests that none of these therapies confer significant 90-day mortality survival over supportive care alone. These results highlight the heterogeneity of therapies and emphasize the need for critical prospective appraisal of their outcomes in SJS and TEN.
Asunto(s)
Quemaduras , Síndrome de Stevens-Johnson , Adulto , Humanos , Síndrome de Stevens-Johnson/tratamiento farmacológico , Síndrome de Stevens-Johnson/etiología , Inmunoglobulinas Intravenosas/uso terapéutico , Estudios Retrospectivos , Estudios Prospectivos , Quemaduras/complicaciones , Ciclosporina/uso terapéutico , Terapia de Inmunosupresión/efectos adversosRESUMEN
BACKGROUND: In the advent of increasing antibiotic resistance, several studies sought to determine antibiotic prescription trends; however, no pattern has been firmly identified particularly for the burned population. We performed a query of burned patients in a large established database to understand differences in antibiotic use related to patient-specific factors. METHODS: Burned patients with systemic antibiotics given within 7 days of injury were identified on the TriNetX database. The patient population was stratified by age, 1-year time intervals of antibiotic prescription from 2004 to 2019, time of antibiotic prescription in 1-day intervals after injury, and % TBSA burned in 10% intervals ranging from < 10% to > 90%. Data were analyzed using χ2 with p < 0.05 considered significant. Pearson coefficients (r2) values were used to correlate differences in antibiotic prescription between age groups and to changes over time. RESULTS: Stratification by age revealed higher use of antibiotics in older burned patients compared to younger patients. Surprisingly, 87.6% of burn patients of those who received antibiotic therapy was on the day of injury. Penicillins and beta-lactam antimicrobials were used most often at a frequency of 64%. No statistically significant differences in rates of antibiotic therapy were observed in burned patients when stratified by %TBSA burned. CONCLUSIONS: The study elucidates current patterns of antibiotic use in burn care in the United States, allowing for improved understanding of both past and present patterns of antibiotic prescription.
Asunto(s)
Quemaduras , Humanos , Estados Unidos , Anciano , Lactante , Quemaduras/tratamiento farmacológico , Antibacterianos/uso terapéutico , Estudios RetrospectivosRESUMEN
INTRODUCTION: Previous analyses of tracheostomy in paediatric burns was hindered by a lack of multi-institution or nationwide analysis. This study aims to explore the effects of tracheostomy in paediatric burn patients in such an analysis. De-identified data was obtained from the TriNetX Research Network database. METHODS: Two cohorts were identified using ICD and CPT codes: paediatric burn patients with tracheostomy (cohort 1) and paediatric burn patients without tracheostomy (cohort 2). Cohorts were matched according to age at diagnosis and pulmonary condition, specifically influenza and pneumonia, respiratory failure, acute upper respiratory infection, and pulmonary collapse. Cohorts were also matched for age at burn diagnosis and surface area burned. Several parameters including infection following a procedure, sepsis, volume depletion, respiratory disorders, laryngeal disorders, pneumonia, and other metrics were also compared. RESULTS: A total of 152 patients were matched according to age and pulmonary condition. Cohort 1 and cohort 2 had a mean age of 4.45 ± 4.06 and 4.39 ± 3.99 years, respectively. Matched patients with tracheostomy had a higher risk for pneumonia, respiratory failure, other respiratory disorders, diseases of the vocal cord and larynx, sepsis, volume depletion, pulmonary edema, and respiratory arrest. The risk ratios for these outcomes were 2.96, 3.5, 3.13, 3.9, 2.5, 2.5, 3.3, and not applicable. Analysis of longitudinal outcomes of paediatric burn patients with tracheostomy vs. those without demonstrated the tracheostomy cohort suffered much worse morbidity and experienced higher health burden across several metrics. CONCLUSION: The potential benefits of tracheostomy in paediatric burn patients should be weighed against these outcomes.
Asunto(s)
Quemaduras , Neumonía , Insuficiencia Respiratoria , Sepsis , Humanos , Niño , Lactante , Preescolar , Quemaduras/cirugía , Estudios Retrospectivos , Traqueostomía , Neumonía/etiología , Insuficiencia Respiratoria/etiología , Sepsis/etiologíaRESUMEN
BACKGROUND: C-reactive protein (CRP) is an acute-phase protein produced in response to inflammation after traumatic injury. We posit that C-reactive protein (CRP) is reliable in predicting morbidity and mortality following severe burn. In this study, we explored the relationship between serum CRP values and clinical outcomes in the severely burned. METHODS: Using the Research Network within the TriNetX database, we queried de-identified burn patient data across the United States and enrolled 36,556 burn patients with reported CRP values from 2006 to 2020. RESULTS: Circulating CRP levels were elevated significantly in patients ≥60 years as well as in males and African Americans (p < 0.05). CRP levels reached the zenith on the first day after burn, and were highest when burn size reached 60% total body surface area (TBSA). After bisecting the data at 10 mg/L of CRP, we compared clinical findings between patient groups (n = 16,284/18,647 in high/low CRP levels). The risk of patient death doubled in the high CRP group from 4.687% to 9.313%, with higher incidences of sepsis, skin infection, and myocardial infarction (p < 0.05). Moreover, mortality increased from 0.9% to 1.926% in those younger than 20 years when comparing the low and high CRP groups, whereas mortality significantly increased from 8.84% to 15.818% in those ≥60 years old (p < 0.05). Both elderly and paediatric groups had significant increases in the diagnosis of sepsis-associated with increased CRP expression. However, incidences of skin infection, pneumonia, and acute kidney injury increased significantly only in the elderly group (p < 0.05). CONCLUSION: Elevated CRP expression is common in burn patients. The factor of age influenced the association of CRP expression to clinical outcomes.
Asunto(s)
Quemaduras , Sepsis , Masculino , Humanos , Niño , Anciano , Persona de Mediana Edad , Quemaduras/complicaciones , Proteína C-Reactiva/metabolismo , Inflamación , Sepsis/complicaciones , MorbilidadRESUMEN
INTRODUCTION: Skin-related infections are drivers of complications following severe burn, therefore a diverse armamentarium of topical antimicrobial agents have been developed. The last 30 years witnessed dramatic changes in surgical intervention and utilization of topical therapies. AREAS COVERED: We explore well-known topical antimicrobial products used in burn care. First, we investigate how changes in the practice of burn surgery influenced choice of topical therapies used. Then, we examine antimicrobial creams and ointments commonly recognized due to their long use in burn care. Next, we dive into antimicrobial solutions commonly used as adjuncts to surgical intervention. Finally, we explore representative antimicrobial dressings, an ever-advancing roster of products in the next era in burn care. We describe how these new agents relate to already established tools in present-day burn care. EXPERT OPINION: In the current day, though the wisdom of early excision and wound closure remains valid, efforts continue to minimize aggressive wound excision and disfiguring donor tissue collection while securing rapid wound closure. To this end, antimicrobial therapies are titrated to optimize operative outcomes and provide non-operative wound care when appropriate. Antimicrobial agents bridge the gap with the next generation of skin substitute and skin replacement therapies.
Asunto(s)
Antiinfecciosos Locales , Antiinfecciosos , Quemaduras , Enfermedades Transmisibles , Infección de Heridas , Administración Tópica , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Quemaduras/complicaciones , Quemaduras/tratamiento farmacológico , Enfermedades Transmisibles/tratamiento farmacológico , Humanos , Cicatrización de Heridas , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/prevención & controlRESUMEN
BACKGROUND: Rhabdomyolysis is a severe condition responsible for up to 10% of acute kidney injury (AKI) cases. Severely burned patients are susceptible to developing both rhabdomyolysis and acute kidney injury, but whether burned patients with rhabdomyolysis are at greater risk of acute kidney injury compared to non-burned patients with rhabdomyolysis is unclear. METHODS: TriNetX, a clinical research platform, was used to obtain electronic medical record information in 3 patient cohorts over the recent 20-year period. Cohort 1 included burn patients who developed rhabdomyolysis, cohort 2 were those who developed rhabdomyolysis due to non-burn causes, and cohort 3 included burn patients who did not develop rhabdomyolysis. Matching was performed to balance demographics and comorbidities for each cohort. Cohorts were then compared for the development of acute kidney injury and death. RESULTS: We found 84 of 111 patients in cohort 1 (75.676%), 56 of 111 patients in cohort 2 (50.45%), and 18 of 111 patients in cohort 3 (16.216%) developed acute kidney injury within 5 days. The odds ratio for developing acute kidney injury for burned patients compared to non-burned patients with rhabdomyolysis was 3.056 with a 95% confidence interval of 1.726 to 5.41 (P < .05), and between burned patients with and without rhabdomyolysis was 16.074 with a 95% confidence interval of 8.263 to 31.268 (P < .05). The incidence of death within 1 year was also significantly higher in cohort 1 (48%) than the other cohorts (9% and 14%, respectively) (P < .05). CONCLUSION: The risk of acute kidney injury and mortality in severely burned patients with rhabdomyolysis is significantly increased compared to matched non-burn patients with rhabdomyolysis or burned patients without rhabdomyolysis.
Asunto(s)
Lesión Renal Aguda , Quemaduras , Rabdomiólisis , Lesión Renal Aguda/epidemiología , Lesión Renal Aguda/etiología , Quemaduras/complicaciones , Femenino , Humanos , Masculino , Oportunidad Relativa , Estudios Retrospectivos , Rabdomiólisis/complicacionesRESUMEN
The use of high-risk donor livers, which is reflective of the gross national shortage of organs available for transplantation, has gained momentum. Despite the demand, many marginal livers are discarded annually. We evaluated the impact of center volume on survival outcomes associated with liver transplantation using high-donor risk index (DRI) allografts. We queried the Scientific Registry of Transplant Recipients database for deceased donor liver transplants (n = 31,576) performed between 2002 and 2008 for patients who were 18 years old or older, and we excluded partial and multiple liver transplants. A high-DRI cohort (n = 15,668), which was composed of patients receiving grafts with DRIs > 1.90, was analyzed separately. Transplant centers (n = 102) were categorized into tertiles by their annual procedure volumes: high-volume centers (HVCs; 78-215 cases per year), medium-volume centers (MVCs; 49-77 cases per year), and low-volume centers (LVCs; 5-48 cases per year). The endpoints were allograft survival and recipient survival. In comparison with their lower volume counterparts, HVCs used donors with higher mean DRIs (2.07 for HVCs, 2.01 for MVCs, and 1.91 for LVCs), more donors who were 60 years old or older (18.02% for HVCs, 16.85% for MVCs, and 12.39% for LVCs), more donors who died after a stroke (46.52% for HVCs, 43.71% for MVCs, and 43.36% for LVCs), and more donation after cardiac death organs (5.04% for HVCs, 4.45% for MVCs, and 3.51% for LVCs, all P values < 0.001). Multivariate risk-adjusted frailty models showed that increased procedure volume at a transplant center led to decreased risks of allograft failure [hazard ratio (HR) = 0.93, 95% confidence interval (CI) = 0.89-0.98, P = 0.002] and recipient death (HR = 0.90, 95% CI = 0.83-0.97, P = 0.004) for high-DRI liver transplants. In conclusion, HVCs more frequently used higher DRI livers and achieved better risk-adjusted allograft and recipient survival. A greater understanding of the outcomes of transplantation with high-DRI livers may improve their utilization, the postoperative outcomes, and future allocation practices.
Asunto(s)
Selección de Donante/estadística & datos numéricos , Supervivencia de Injerto , Hospitales/estadística & datos numéricos , Trasplante de Hígado/efectos adversos , Evaluación de Procesos y Resultados en Atención de Salud/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Donantes de Tejidos/provisión & distribución , Adulto , Distribución de Chi-Cuadrado , Femenino , Humanos , Estimación de Kaplan-Meier , Trasplante de Hígado/mortalidad , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Sistema de Registros , Análisis de Regresión , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: All open and laparoscopic colectomies submitted to the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) were evaluated for trends and improvements in operative outcomes. METHODS: 48,247 adults (≥18 y old) underwent colectomy in ACS NSQIP, as grouped by surgical approach (laparoscopic versus open), urgency (emergent versus elective), and operative year (2005 to 2008). Primary outcomes measured morbidity, mortality, perioperative, and postoperative complications. RESULTS: The proportion of laparoscopic colectomies performed increased annually (26.3% to 34.0%), while open colectomies decreased (73.7% to 66.0%; P < 0.0001). Most emergent colectomies were open procedures (93.5%) representing 24.3% of all open cases. The overall risk-adjusted morbidity and mortality for all colectomy procedures did not show a statistically significant change over time, however, morbidity and mortality increased among open colectomies (r = 0.03) and decreased among laparoscopic colectomies (r = -0.04; P < 0.0001). Postoperative complications reduced significantly including superficial surgical site infections (9.17% to 8.20%, P < 0.004), pneumonia (4.60% to 3.97%, P < 0.0001), and sepsis (4.72%, 2005; 6.81%, 2006; 5.62%, 2007; 5.09%, 2008; P < 0.0002). Perioperative improvements included operative time (169.2 to 160.0 min), PRBC transfusions (0.27 to 0.25 units) and length of stay (10.5 to 6.61 d; P < 0.0001). CONCLUSION: It appears that laparoscopic colectomies are growing in popularity over open colectomies, but the need for emergent open procedures remains unchanged. Across all colectomies, however, key postoperative and perioperative complications have improved over time. Participation in ACS NSQIP demonstrates quality improvement and may encourage greater enrollment.
Asunto(s)
Colectomía/normas , Procedimientos Quirúrgicos Electivos/normas , Laparoscopía/normas , Evaluación de Procesos y Resultados en Atención de Salud/estadística & datos numéricos , Garantía de la Calidad de Atención de Salud , Adulto , Anciano , Anciano de 80 o más Años , Colectomía/mortalidad , Bases de Datos Factuales/estadística & datos numéricos , Procedimientos Quirúrgicos Electivos/mortalidad , Tratamiento de Urgencia/mortalidad , Tratamiento de Urgencia/normas , Femenino , Humanos , Laparoscopía/mortalidad , Masculino , Persona de Mediana Edad , Morbilidad , Complicaciones Posoperatorias/mortalidad , Estudios Retrospectivos , Factores de Riesgo , Adulto JovenRESUMEN
BACKGROUND: A growth in the utilization of high-risk allografts is reflective of a critical national shortage and the increasing waiting list mortality. Using risk-adjusted models, the aim of the present study was to determine whether a volume-outcome relationship existed among liver transplants at high risk for allograft failure. METHODS: From 2002 to 2008, the Scientific Registry of Transplant Recipients (SRTR) database for all adult deceased donor liver transplants (n = 31 587) was queried. Transplant centres (n = 102) were categorized by volume into tertiles: low (LVC; 31 cases/year), medium (MVC: 64 cases/year) and high (HVC: 102 cases/year). Donor risk comparison groups were stratified by quartiles of the Donor Risk Index (DRI) spectrum: low risk (DRI ≤ 1.63), moderate risk (1.64 > DRI > 1.90), high risk (1.91 > DRI > 2.26) and very high risk (DRI ≥ 2.27). RESULTS: HVC more frequently used higher-risk livers (median DRI: LVC: 1.82, MVC: 1.90, HVC: 1.97; P < 0.0001) and achieved better risk adjusted allograft survival outcomes compared with LVC (HR: 0.90, 95%CI: 0.85-0.95). For high and very high risk groups, transplantation at a HVC did contribute to improved graft survival [high risk: hazard ratio (HR): 0.85, 95% confidence interval (CI): 0.76-0.96; Very High Risk: HR: 0.88, 95%CI: 0.78-0.99]. CONCLUSION: While DRI remains an important aspect of allograft survival prediction models, liver transplantation at a HVC appears to result in improved allograft survival with high and very high risk DRI organs compared with LVC.
Asunto(s)
Supervivencia de Injerto , Trasplante de Hígado/estadística & datos numéricos , Trasplantes/estadística & datos numéricos , Listas de Espera/mortalidad , Adulto , Femenino , Departamentos de Hospitales/estadística & datos numéricos , Humanos , Trasplante de Hígado/mortalidad , Masculino , Factores de Riesgo , Trasplante Homólogo , Estados UnidosRESUMEN
OBJECTIVES: The campaign against tobacco addiction and smoking continues to play an important role in public health. However, referrals to outpatient tobacco cessation programs by emergency physicians are rarely pursued by patients following discharge. This study explored cost as a barrier to follow-up. METHODS: The study was performed at a large urban hospital emergency department (ED) in Camden, New Jersey. Enrollment included adults who reported tobacco use in the past 30 days. Study participants were informed about a "Stop Smoking Clinic" affiliated with the hospital and, depending on enrollment date, cost of treatment was advertised as $150 (standard fee), $20 (reduced fee), or $0 (no fee). Monitoring of patient inquiries and visits to the clinic was performed for 6 months following enrollment of the last study subject. RESULTS: The analyzed sample consisted of 577 tobacco users. There were no statistically significant demographic differences between treatment groups (p > 0.05). Two-hundred forty-seven (43%) participants reported "very much" interest in smoking cessation. However, there was no significant difference in initiating treatment with the Stop Smoking Clinic across experimental condition. Only a single subject, enrolled in the no-fee phase, initiated treatment with the clinic. CONCLUSIONS: Cost is unlikely to be the only barrier to pursing outpatient tobacco treatment after an ED visit. Further research is needed to determine the critical components of counseling and referral that maximize postdischarge treatment initiation.
Asunto(s)
Servicio de Urgencia en Hospital , Servicio Ambulatorio en Hospital/economía , Derivación y Consulta/estadística & datos numéricos , Cese del Hábito de Fumar/economía , Cese del Hábito de Fumar/estadística & datos numéricos , Adulto , Atención Ambulatoria/economía , Atención Ambulatoria/estadística & datos numéricos , Femenino , Hospitales Urbanos , Humanos , Masculino , Persona de Mediana Edad , New JerseyRESUMEN
OBJECTIVE: The objective of this study is to describe the imaging features of non-neoplastic masses suspected of being tumor recurrences adjacent to allografts. The allografts were utilized for the treatment of various musculoskeletal tumors. MATERIALS AND METHODS: We reviewed the medical records and imaging studies of 56 patients who were suspected of having recurrent tumors following surgical resection and allograft replacement treatment for a variety of musculoskeletal neoplasms. The imaging modalities included radiographs, CT, and MRI. RESULTS: There were 47 cases of recurrent tumors. All tumor recurrences were in the soft tissues of the surgical bed (41 patients), or in the native bone adjacent to the host/allograft junction (6 patients). None of the recurrences originated in the allografts. Nine patients suspected of having recurrences were discovered to have non-neoplastic masses. Five of these were very closely related to the allograft, wrapping around parts of the allograft, and the other 4 were in the surgical bed, 2 of which were abscesses and two were seromas. CONCLUSION: Most masses arising in the vicinity of allografts implanted following resection of musculoskeletal tumors represent recurrent neoplasms. A minority are reactive processes or abscesses or fluid collections. These "pseudoneoplasms," specifically those closely related to the allografts, have specific imaging characteristics that help distinguish them from recurrent tumors.