JAMA otolaryngology-- head & neck surgery, May 1, 2013
Importance: Subglottic stenosis (SGS) is a severe, acquired, potentially life-threatening disease... more Importance: Subglottic stenosis (SGS) is a severe, acquired, potentially life-threatening disease that can be caused by endotracheal tube intubation. Newborns and neonates are particularly susceptible to SGS owing to the small caliber of their airway. Objective: To demonstrate optical coherence tomography (OCT) capabilities in detecting injury and scar formation using a rabbit model. Optical coherence tomography may provide a noninvasive, bedside or intensive care unit modality for the identification of early airway trauma with the intention of preventing progression to SGS and can image the upper airway through an existing endotracheal tube coupled with a small fiber-optic probe. Design: Rabbits underwent suspension laryngoscopy with induction of of SGS via epithelial injury. This model was used to test and develop our advanced, high-speed, high-resolution OCT imaging system using a 3-dimensional microelectromechanical systems-based scanning device integrated with a fiber-optic probe to acquire highresolution anatomic images of the subglottic epithelium and lamina propria. Setting: All experiments were performed at the Beckman Laser Institute animal operating room. Intervention or Exposure: Optical coherence tomography and endoscopy was performed with suspension laryngoscopy at 6 different time intervals and compared with conventional digital endoscopic images and histologic sections. Fifteen rabbits were killed at 3, 7, 14, 21, and 42 days after the induction of SGS. The laryngotracheal complexes were serially sectioned for histologic analysis. Main Outcome and Measure: Histologic sections, endoscopic images, and OCT images were compared with one another to determine if OCT could accurately delineate the degree of SGS achieved. Results: The rabbit model was able to reliably and reproducibly achieve grade I SGS. The real-time OCT imaging system was able to (1) identify multiple structures in the airway; (2) delineate different tissue planes, such as the epithelium, basement membrane, lamina propria, and cartilage; and (3) detect changes in each tissue plane produced by trauma. Optical coherence tomography was also able demonstrate a clear picture of airway injury that correlated with the endoscopic and histologic images. With subjective review, 3 patients had high correlation between OCT and histologic images, 10 demonstrated some correlation with histologic images, and 2 showed little to no correlation with histologic images.
Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular mat... more Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular matrix (ECM) components, including collagens, fibrin, fibronectin, proteoglycans, glycosaminoglycans, and matricellular proteins, can be considered potent protagonists of fibroblast survival, migration, and metabolism. Recent Advances: Advances in tissue culture, tissue engineering, and ex vivo models have made the examination and precise measurements of ECM components in wound healing possible. Likewise, the development of specific transgenic animal models has created the opportunity to characterize the role of various ECM molecules in healing wounds. In addition, the recent characterization of new ECM molecules, including matricellular proteins, dermatopontin, and FACIT collagens (Fibril-Associated Collagens with Interrupted Triple helices), further demonstrates our cursory knowledge of the ECM in coordinated wound healing. Critical Issues: The manipulation and augmentation of ECM components in the healing wound is emerging in patient care, as demonstrated by the use of acellular dermal matrices, tissue scaffolds, and wound dressings or topical products bearing ECM proteins such as collagen, hyaluronan (HA), or elastin. Once thought of as neutral structural proteins, these molecules are now known to directly influence many aspects of cellular wound healing. Future Directions: The role that ECM molecules, such as CCN2, osteopontin, and secreted protein, acidic and rich in cysteine, play in signaling homing of fibroblast progenitor cells to sites of injury invites future research as we continue investigating the heterotopic origin of certain populations of fibroblasts in a healing wound. Likewise, research into differently sized fragments of the same polymeric ECM molecule is warranted as we learn that fragments of molecules such as HA and tenascin-C can have opposing effects on dermal fibroblasts.
Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wou... more Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wound healing, delay in treatment, disability, or death. Traditional approach centers on early debridement, fluid resuscitation, and adjunct intravenous antibiotics. These modalities often prove inadequate in burns, where compromised local vasculature limits the tissue penetration of systemic antibiotics. Here, we demonstrate the treatment of infected burns with topical delivery of ultrahigh concentrations of antibiotics. Standardized burns were inoculated with Staphylococcus aureus or Pseudomonas aeruginosa. After debridement, burns were treated with either gentamicin (2 mg/mL) or minocycline (1 mg/mL) at concentrations greater than 1,000 times the minimum inhibitory concentration. Amount of bacteria was quantified in tissue biopsies and wound fluid following treatment. After six days of gentamicin or minocycline treatment, S. aureus counts decreased from 4.2 to 0.31 and 0.72 log CFU/g in tissue, respectively. Similarly, P. aeruginosa counts decreased from 2.5 to 0.0 and 1.5 log CFU/g in tissue, respectively. Counts of both S. aureus and P. aeruginosa remained at a baseline of 0.0 log CFU/mL in wound fluid for both treatment groups. The findings here demonstrate that super-therapeutic concentrations of antibiotics delivered topically can rapidly reduce bacterial counts in infected full-thickness porcine burns. This treatment approach may aid wound bed preparation and accelerate time to grafting.
Injury to the skin can predispose individuals to invasive infection. The standard of care for inf... more Injury to the skin can predispose individuals to invasive infection. The standard of care for infected wounds is treatment with intravenous antibiotics. However, antibiotics delivered intravenously may have poor tissue penetration and be dose limited by systemic side effects. Topical delivery of antibiotics reduces systemic complications and delivers increased drug concentrations directly to the wound. Porcine full-thickness wounds infected with Staphylococcus aureus were treated with ultrahigh concentrations (over 1000 times the minimum inhibitory concentration) of gentamicin using an incubator-like wound healing platform. The aim of the present study was to evaluate clearance of infection and reduction in inflammation following treatment. Gentamicin cytotoxicity was evaluated by in vitro assays. Application of 2000 μg/ml gentamicin decreased bacterial counts in wound tissue from 7.2 ± 0.3 log colony-forming units/g to 2.6 ± 0.6 log colony-forming units/g in 6 hours, with no reduct...
Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular mat... more Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular matrix (ECM) components, including collagens, fibrin, fibronectin, proteoglycans, glycosaminoglycans, and matricellular proteins, can be considered potent protagonists of fibroblast survival, migration, and metabolism. Recent Advances: Advances in tissue culture, tissue engineering, and ex vivo models have made the examination and precise measurements of ECM components in wound healing possible. Likewise, the development of specific transgenic animal models has created the opportunity to characterize the role of various ECM molecules in healing wounds. In addition, the recent characterization of new ECM molecules, including matricellular proteins, dermatopontin, and FACIT collagens (Fibril-Associated Collagens with Interrupted Triple helices), further demonstrates our cursory knowledge of the ECM in coordinated wound healing. Critical Issues: The manipulation and augmentation of ECM components in the healing wound is emerging in patient care, as demonstrated by the use of acellular dermal matrices, tissue scaffolds, and wound dressings or topical products bearing ECM proteins such as collagen, hyaluronan (HA), or elastin. Once thought of as neutral structural proteins, these molecules are now known to directly influence many aspects of cellular wound healing. Future Directions: The role that ECM molecules, such as CCN2, osteopontin, and secreted protein, acidic and rich in cysteine, play in signaling homing of fibroblast progenitor cells to sites of injury invites future research as we continue investigating the heterotopic origin of certain populations of fibroblasts in a healing wound. Likewise, research into differently sized fragments of the same polymeric ECM molecule is warranted as we learn that fragments of molecules such as HA and tenascin-C can have opposing effects on dermal fibroblasts.
ePlasty: Open Access Journal of Plastic and Reconstructive Surgery, Jun 27, 2014
Electromechanical reshaping (EMR) involves the application of an electrical current to mechanical... more Electromechanical reshaping (EMR) involves the application of an electrical current to mechanically deformed cartilage to create sustained tissue shape change. Although EMR may evolve to become an inexpensive and reliable way of producing shape change in cartilage during reconstructive surgery, the precise mechanism of EMR is unknown. We aim to examine the isolated effect of protonation (pH) on shape change in cartilage. Nasal septal cartilages of rabbits were mechanically deformed and placed in a rigid jig. The deformed cartilages were submerged in isotonic phosphate buffered saline baths (osm = 290 mmol/Kg) with a pH of 3 (N = 51), pH of 7 (N = 51), and a pH of 11 (N = 51) for 15 minutes. Following re-equilibration, specimens were removed from their jig and the angle change from baseline was measured using digital micrometry. Significant shape change was noted in all specimens, with an angle change of 33.6°, 33.3°, and 32.0° experienced by the pH of 3, 7, and 11 groups, respective...
Importance—Subglottic stenosis (SGS) is a severe, acquired, potentially life-threatening disease ... more Importance—Subglottic stenosis (SGS) is a severe, acquired, potentially life-threatening disease that can be caused by endotracheal tube intubation. Newborns and neonates are particularly susceptible to SGS owing to the small caliber of their airway. Objective—To demonstrate optical coherence tomography (OCT) capabilities in detecting injury and scar formation using a rabbit model. Optical coherence tomography may provide a noninvasive, bedside or intensive care unit modality for the identification of early airway trauma with the intention of preventing progression to SGS and can image the upper airway through an existing endotracheal tube coupled with a small fiber-optic probe. Design—Rabbits underwent suspension laryngoscopy with induction of of SGS via epithelial injury. This model was used to test and develop our advanced, high-speed, high-resolution OCT imaging system using a 3-dimensional microelectromechanical systems-based scanning device integrated with a fiber-optic probe ...
BACKGROUND Colouterine fistula is one of the rarest complications of diverticulitis, with 23 case... more BACKGROUND Colouterine fistula is one of the rarest complications of diverticulitis, with 23 cases reported in the world literature to our knowledge. Because of its infrequent presentation, there are no standardized diagnostic modalities for this disease, but almost all patients will require surgical treatment. CASE An afebrile, 66-year-old woman with known diverticulitis presented with vaginal bleeding and discharge of 1 day's duration. Based on imaging she was believed to have a complex adnexal mass. However, it was proven intraoperatively to be a colouterine fistula. CONCLUSION Although extremely uncommon, the diagnosis of a colouterine fistula can be made with pelvic examination, diagnostic imaging, or surgical exploration. The surgical treatment of colouterine fistulae varies on the acuity of the patient's diverticular disease and the surgeon's suspicion of malignancy.
Introduction: Electromechanical reshaping (EMR) involves the application of an electrical current... more Introduction: Electromechanical reshaping (EMR) involves the application of an electrical current to mechanically deformed cartilage to create sustained tissue shape change. Although EMR may evolve to become an inexpensive and reliable way of producing shape change in cartilage during reconstructive surgery, the precise mechanism of EMR is unknown. We aim to examine the isolated effect of protonation (pH) on shape change in cartilage. Methods: Nasal septal cartilages of rabbits were mechanically deformed and placed in a rigid jig. The deformed cartilages were submerged in isotonic phosphate buffered saline baths (osm = 290 mmol/Kg) with a pH of 3 (N = 51), pH of 7 (N = 51), and a pH of 11 (N = 51) for 15 minutes. Following re-equilibration, specimens were removed from their jig and the angle change from baseline was measured using digital micrometry. Results: Significant shape change was noted in all specimens, with an angle change of 33.6°, 33.3°, and 32.0° experienced by the pH of...
Colouterine fistula is one of the rarest complications of diverticulitis, with 23 cases reported ... more Colouterine fistula is one of the rarest complications of diverticulitis, with 23 cases reported in the world literature to our knowledge. Because of its infrequent presentation, there are no standardized diagnostic modalities for this disease, but almost all patients will require surgical treatment. An afebrile, 66-year-old woman with known diverticulitis presented with vaginal bleeding and discharge of 1 day's duration. Based on imaging she was believed to have a complex adnexal mass. However, it was proven intraoperatively to be a colouterine fistula. Although extremely uncommon, the diagnosis of a colouterine fistula can be made with pelvic examination, diagnostic imaging, or surgical exploration. The surgical treatment of colouterine fistulae varies on the acuity of the patient's diverticular disease and the surgeon's suspicion of malignancy.
Electromechanical reshaping (EMR) involves the application of an electrical current to mechanical... more Electromechanical reshaping (EMR) involves the application of an electrical current to mechanically deformed cartilage to create sustained tissue shape change. Although EMR may evolve to become an inexpensive and reliable way of producing shape change in cartilage during reconstructive surgery, the precise mechanism of EMR is unknown. We aim to examine the isolated effect of protonation (pH) on shape change in cartilage. Nasal septal cartilages of rabbits were mechanically deformed and placed in a rigid jig. The deformed cartilages were submerged in isotonic phosphate buffered saline baths (osm = 290 mmol/Kg) with a pH of 3 (N = 51), pH of 7 (N = 51), and a pH of 11 (N = 51) for 15 minutes. Following re-equilibration, specimens were removed from their jig and the angle change from baseline was measured using digital micrometry. Significant shape change was noted in all specimens, with an angle change of 33.6°, 33.3°, and 32.0° experienced by the pH of 3, 7, and 11 groups, respectively. Despite a trend toward increased shape change in the acidic treatment, there was no significant difference between groups. Although current evidence indicates that dynamic oxidation-reduction reactions within the extracellular matrix of cartilage may be implicated in EMR-induced shape change, when pH was isolated as a single variable it was not sufficient to produce cartilage shape change.
Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wou... more Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wound healing, delay in treatment, disability, or death. Traditional approach centers on early debridement, fluid resuscitation, and adjunct intravenous antibiotics. These modalities often prove inadequate in burns, where compromised local vasculature limits the tissue penetration of systemic antibiotics. Here, we demonstrate the treatment of infected burns with topical delivery of ultrahigh concentrations of antibiotics. Standardized burns were inoculated with Staphylococcus aureus or Pseudomonas aeruginosa. After debridement, burns were treated with either gentamicin (2 mg/mL) or minocycline (1 mg/mL) at concentrations greater than 1,000 times the minimum inhibitory concentration. Amount of bacteria was quantified in tissue biopsies and wound fluid following treatment. After six days of gentamicin or minocycline treatment, S. aureus counts decreased from 4.2 to 0.31 and 0.72 log CFU/g in tissue, respectively. Similarly, P. aeruginosa counts decreased from 2.5 to 0.0 and 1.5 log CFU/g in tissue, respectively. Counts of both S. aureus and P. aeruginosa remained at a baseline of 0.0 log CFU/mL in wound fluid for both treatment groups. The findings here demonstrate that super-therapeutic concentrations of antibiotics delivered topically can rapidly reduce bacterial counts in infected full-thickness porcine burns. This treatment approach may aid wound bed preparation and accelerate time to grafting. This article is protected by copyright. All rights reserved.
Electromechanical reshaping (EMR) involves the application of an electrical current to mechanical... more Electromechanical reshaping (EMR) involves the application of an electrical current to mechanically deformed cartilage to create sustained tissue shape change. Although EMR may evolve to become an inexpensive and reliable way of producing shape change in cartilage during reconstructive surgery, the precise mechanism of EMR is unknown. We aim to examine the isolated effect of protonation (pH) on shape change in cartilage. Nasal septal cartilages of rabbits were mechanically deformed and placed in a rigid jig. The deformed cartilages were submerged in isotonic phosphate buffered saline baths (osm = 290 mmol/Kg) with a pH of 3 (N = 51), pH of 7 (N = 51), and a pH of 11 (N = 51) for 15 minutes. Following re-equilibration, specimens were removed from their jig and the angle change from baseline was measured using digital micrometry. Significant shape change was noted in all specimens, with an angle change of 33.6°, 33.3°, and 32.0° experienced by the pH of 3, 7, and 11 groups, respective...
Occult submucous cleft palate is a congenital deformity characterized by deficient union of the m... more Occult submucous cleft palate is a congenital deformity characterized by deficient union of the muscles that normally cross the velum and aid in elevation of the soft palate. Despite this insufficient muscle coverage, occult submucous cleft palate by definition lacks clear external anatomic landmarks. This absence of anatomic signs makes diagnosis of occult submucous cleft less obvious, more dependent on ancillary tests, and potentially missed entirely. Current diagnostic methodologies are limited and often are unrevealing in the presurgical patient; however, a missed diagnosis of occult submucous cleft palate can result in velopharyngeal insufficiency and major functional impairment in patients after surgery on the oropharynx. By accurately and easily diagnosing occult submucous cleft palate, it is possible to defer or modify pharyngeal surgical intervention that may further impair velopharyngeal function in susceptible patients. In this report, we introduce transillumination of the soft palate using a transnasal or transoral flexible endoscope as an inexpensive and simple technique for identification of submucous cleft palate. The use of transillumination of an occult submucous cleft palate is illustrated in a patient case and is compared to other current diagnostic methodologies.
Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular mat... more Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular matrix (ECM) components, including collagens, fibrin, fibronectin, proteoglycans, glycosaminoglycans, and matricellular proteins, can be considered potent protagonists of fibroblast survival, migration, and metabolism. Recent Advances: Advances in tissue culture, tissue engineering, and ex vivo models have made the examination and precise measurements of ECM components in wound healing possible. Likewise, the development of specific transgenic animal models has created the opportunity to characterize the role of various ECM molecules in healing wounds. In addition, the recent characterization of new ECM molecules, including matricellular proteins, dermatopontin, and FACIT collagens (Fibril-Associated Collagens with Interrupted Triple helices), further demonstrates our cursory knowledge of the ECM in coordinated wound healing. Critical Issues: The manipulation and augmentation of ECM components in the healing wound is emerging in patient care, as demonstrated by the use of acellular dermal matrices, tissue scaffolds, and wound dressings or topical products bearing ECM proteins such as collagen, hyaluronan (HA), or elastin. Once thought of as neutral structural proteins, these molecules are now known to directly influence many aspects of cellular wound healing. Future Directions: The role that ECM molecules, such as CCN2, osteopontin, and secreted protein, acidic and rich in cysteine, play in signaling homing of fibroblast progenitor cells to sites of injury invites future research as we continue investigating the heterotopic origin of certain populations of fibroblasts in a healing wound. Likewise, research into differently sized fragments of the same polymeric ECM molecule is warranted as we learn that fragments of molecules such as HA and tenascin-C can have opposing effects on dermal fibroblasts.
JAMA otolaryngology-- head & neck surgery, May 1, 2013
Importance: Subglottic stenosis (SGS) is a severe, acquired, potentially life-threatening disease... more Importance: Subglottic stenosis (SGS) is a severe, acquired, potentially life-threatening disease that can be caused by endotracheal tube intubation. Newborns and neonates are particularly susceptible to SGS owing to the small caliber of their airway. Objective: To demonstrate optical coherence tomography (OCT) capabilities in detecting injury and scar formation using a rabbit model. Optical coherence tomography may provide a noninvasive, bedside or intensive care unit modality for the identification of early airway trauma with the intention of preventing progression to SGS and can image the upper airway through an existing endotracheal tube coupled with a small fiber-optic probe. Design: Rabbits underwent suspension laryngoscopy with induction of of SGS via epithelial injury. This model was used to test and develop our advanced, high-speed, high-resolution OCT imaging system using a 3-dimensional microelectromechanical systems-based scanning device integrated with a fiber-optic probe to acquire highresolution anatomic images of the subglottic epithelium and lamina propria. Setting: All experiments were performed at the Beckman Laser Institute animal operating room. Intervention or Exposure: Optical coherence tomography and endoscopy was performed with suspension laryngoscopy at 6 different time intervals and compared with conventional digital endoscopic images and histologic sections. Fifteen rabbits were killed at 3, 7, 14, 21, and 42 days after the induction of SGS. The laryngotracheal complexes were serially sectioned for histologic analysis. Main Outcome and Measure: Histologic sections, endoscopic images, and OCT images were compared with one another to determine if OCT could accurately delineate the degree of SGS achieved. Results: The rabbit model was able to reliably and reproducibly achieve grade I SGS. The real-time OCT imaging system was able to (1) identify multiple structures in the airway; (2) delineate different tissue planes, such as the epithelium, basement membrane, lamina propria, and cartilage; and (3) detect changes in each tissue plane produced by trauma. Optical coherence tomography was also able demonstrate a clear picture of airway injury that correlated with the endoscopic and histologic images. With subjective review, 3 patients had high correlation between OCT and histologic images, 10 demonstrated some correlation with histologic images, and 2 showed little to no correlation with histologic images.
Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular mat... more Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular matrix (ECM) components, including collagens, fibrin, fibronectin, proteoglycans, glycosaminoglycans, and matricellular proteins, can be considered potent protagonists of fibroblast survival, migration, and metabolism. Recent Advances: Advances in tissue culture, tissue engineering, and ex vivo models have made the examination and precise measurements of ECM components in wound healing possible. Likewise, the development of specific transgenic animal models has created the opportunity to characterize the role of various ECM molecules in healing wounds. In addition, the recent characterization of new ECM molecules, including matricellular proteins, dermatopontin, and FACIT collagens (Fibril-Associated Collagens with Interrupted Triple helices), further demonstrates our cursory knowledge of the ECM in coordinated wound healing. Critical Issues: The manipulation and augmentation of ECM components in the healing wound is emerging in patient care, as demonstrated by the use of acellular dermal matrices, tissue scaffolds, and wound dressings or topical products bearing ECM proteins such as collagen, hyaluronan (HA), or elastin. Once thought of as neutral structural proteins, these molecules are now known to directly influence many aspects of cellular wound healing. Future Directions: The role that ECM molecules, such as CCN2, osteopontin, and secreted protein, acidic and rich in cysteine, play in signaling homing of fibroblast progenitor cells to sites of injury invites future research as we continue investigating the heterotopic origin of certain populations of fibroblasts in a healing wound. Likewise, research into differently sized fragments of the same polymeric ECM molecule is warranted as we learn that fragments of molecules such as HA and tenascin-C can have opposing effects on dermal fibroblasts.
Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wou... more Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wound healing, delay in treatment, disability, or death. Traditional approach centers on early debridement, fluid resuscitation, and adjunct intravenous antibiotics. These modalities often prove inadequate in burns, where compromised local vasculature limits the tissue penetration of systemic antibiotics. Here, we demonstrate the treatment of infected burns with topical delivery of ultrahigh concentrations of antibiotics. Standardized burns were inoculated with Staphylococcus aureus or Pseudomonas aeruginosa. After debridement, burns were treated with either gentamicin (2 mg/mL) or minocycline (1 mg/mL) at concentrations greater than 1,000 times the minimum inhibitory concentration. Amount of bacteria was quantified in tissue biopsies and wound fluid following treatment. After six days of gentamicin or minocycline treatment, S. aureus counts decreased from 4.2 to 0.31 and 0.72 log CFU/g in tissue, respectively. Similarly, P. aeruginosa counts decreased from 2.5 to 0.0 and 1.5 log CFU/g in tissue, respectively. Counts of both S. aureus and P. aeruginosa remained at a baseline of 0.0 log CFU/mL in wound fluid for both treatment groups. The findings here demonstrate that super-therapeutic concentrations of antibiotics delivered topically can rapidly reduce bacterial counts in infected full-thickness porcine burns. This treatment approach may aid wound bed preparation and accelerate time to grafting.
Injury to the skin can predispose individuals to invasive infection. The standard of care for inf... more Injury to the skin can predispose individuals to invasive infection. The standard of care for infected wounds is treatment with intravenous antibiotics. However, antibiotics delivered intravenously may have poor tissue penetration and be dose limited by systemic side effects. Topical delivery of antibiotics reduces systemic complications and delivers increased drug concentrations directly to the wound. Porcine full-thickness wounds infected with Staphylococcus aureus were treated with ultrahigh concentrations (over 1000 times the minimum inhibitory concentration) of gentamicin using an incubator-like wound healing platform. The aim of the present study was to evaluate clearance of infection and reduction in inflammation following treatment. Gentamicin cytotoxicity was evaluated by in vitro assays. Application of 2000 μg/ml gentamicin decreased bacterial counts in wound tissue from 7.2 ± 0.3 log colony-forming units/g to 2.6 ± 0.6 log colony-forming units/g in 6 hours, with no reduct...
Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular mat... more Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular matrix (ECM) components, including collagens, fibrin, fibronectin, proteoglycans, glycosaminoglycans, and matricellular proteins, can be considered potent protagonists of fibroblast survival, migration, and metabolism. Recent Advances: Advances in tissue culture, tissue engineering, and ex vivo models have made the examination and precise measurements of ECM components in wound healing possible. Likewise, the development of specific transgenic animal models has created the opportunity to characterize the role of various ECM molecules in healing wounds. In addition, the recent characterization of new ECM molecules, including matricellular proteins, dermatopontin, and FACIT collagens (Fibril-Associated Collagens with Interrupted Triple helices), further demonstrates our cursory knowledge of the ECM in coordinated wound healing. Critical Issues: The manipulation and augmentation of ECM components in the healing wound is emerging in patient care, as demonstrated by the use of acellular dermal matrices, tissue scaffolds, and wound dressings or topical products bearing ECM proteins such as collagen, hyaluronan (HA), or elastin. Once thought of as neutral structural proteins, these molecules are now known to directly influence many aspects of cellular wound healing. Future Directions: The role that ECM molecules, such as CCN2, osteopontin, and secreted protein, acidic and rich in cysteine, play in signaling homing of fibroblast progenitor cells to sites of injury invites future research as we continue investigating the heterotopic origin of certain populations of fibroblasts in a healing wound. Likewise, research into differently sized fragments of the same polymeric ECM molecule is warranted as we learn that fragments of molecules such as HA and tenascin-C can have opposing effects on dermal fibroblasts.
ePlasty: Open Access Journal of Plastic and Reconstructive Surgery, Jun 27, 2014
Electromechanical reshaping (EMR) involves the application of an electrical current to mechanical... more Electromechanical reshaping (EMR) involves the application of an electrical current to mechanically deformed cartilage to create sustained tissue shape change. Although EMR may evolve to become an inexpensive and reliable way of producing shape change in cartilage during reconstructive surgery, the precise mechanism of EMR is unknown. We aim to examine the isolated effect of protonation (pH) on shape change in cartilage. Nasal septal cartilages of rabbits were mechanically deformed and placed in a rigid jig. The deformed cartilages were submerged in isotonic phosphate buffered saline baths (osm = 290 mmol/Kg) with a pH of 3 (N = 51), pH of 7 (N = 51), and a pH of 11 (N = 51) for 15 minutes. Following re-equilibration, specimens were removed from their jig and the angle change from baseline was measured using digital micrometry. Significant shape change was noted in all specimens, with an angle change of 33.6°, 33.3°, and 32.0° experienced by the pH of 3, 7, and 11 groups, respective...
Importance—Subglottic stenosis (SGS) is a severe, acquired, potentially life-threatening disease ... more Importance—Subglottic stenosis (SGS) is a severe, acquired, potentially life-threatening disease that can be caused by endotracheal tube intubation. Newborns and neonates are particularly susceptible to SGS owing to the small caliber of their airway. Objective—To demonstrate optical coherence tomography (OCT) capabilities in detecting injury and scar formation using a rabbit model. Optical coherence tomography may provide a noninvasive, bedside or intensive care unit modality for the identification of early airway trauma with the intention of preventing progression to SGS and can image the upper airway through an existing endotracheal tube coupled with a small fiber-optic probe. Design—Rabbits underwent suspension laryngoscopy with induction of of SGS via epithelial injury. This model was used to test and develop our advanced, high-speed, high-resolution OCT imaging system using a 3-dimensional microelectromechanical systems-based scanning device integrated with a fiber-optic probe ...
BACKGROUND Colouterine fistula is one of the rarest complications of diverticulitis, with 23 case... more BACKGROUND Colouterine fistula is one of the rarest complications of diverticulitis, with 23 cases reported in the world literature to our knowledge. Because of its infrequent presentation, there are no standardized diagnostic modalities for this disease, but almost all patients will require surgical treatment. CASE An afebrile, 66-year-old woman with known diverticulitis presented with vaginal bleeding and discharge of 1 day's duration. Based on imaging she was believed to have a complex adnexal mass. However, it was proven intraoperatively to be a colouterine fistula. CONCLUSION Although extremely uncommon, the diagnosis of a colouterine fistula can be made with pelvic examination, diagnostic imaging, or surgical exploration. The surgical treatment of colouterine fistulae varies on the acuity of the patient's diverticular disease and the surgeon's suspicion of malignancy.
Introduction: Electromechanical reshaping (EMR) involves the application of an electrical current... more Introduction: Electromechanical reshaping (EMR) involves the application of an electrical current to mechanically deformed cartilage to create sustained tissue shape change. Although EMR may evolve to become an inexpensive and reliable way of producing shape change in cartilage during reconstructive surgery, the precise mechanism of EMR is unknown. We aim to examine the isolated effect of protonation (pH) on shape change in cartilage. Methods: Nasal septal cartilages of rabbits were mechanically deformed and placed in a rigid jig. The deformed cartilages were submerged in isotonic phosphate buffered saline baths (osm = 290 mmol/Kg) with a pH of 3 (N = 51), pH of 7 (N = 51), and a pH of 11 (N = 51) for 15 minutes. Following re-equilibration, specimens were removed from their jig and the angle change from baseline was measured using digital micrometry. Results: Significant shape change was noted in all specimens, with an angle change of 33.6°, 33.3°, and 32.0° experienced by the pH of...
Colouterine fistula is one of the rarest complications of diverticulitis, with 23 cases reported ... more Colouterine fistula is one of the rarest complications of diverticulitis, with 23 cases reported in the world literature to our knowledge. Because of its infrequent presentation, there are no standardized diagnostic modalities for this disease, but almost all patients will require surgical treatment. An afebrile, 66-year-old woman with known diverticulitis presented with vaginal bleeding and discharge of 1 day's duration. Based on imaging she was believed to have a complex adnexal mass. However, it was proven intraoperatively to be a colouterine fistula. Although extremely uncommon, the diagnosis of a colouterine fistula can be made with pelvic examination, diagnostic imaging, or surgical exploration. The surgical treatment of colouterine fistulae varies on the acuity of the patient's diverticular disease and the surgeon's suspicion of malignancy.
Electromechanical reshaping (EMR) involves the application of an electrical current to mechanical... more Electromechanical reshaping (EMR) involves the application of an electrical current to mechanically deformed cartilage to create sustained tissue shape change. Although EMR may evolve to become an inexpensive and reliable way of producing shape change in cartilage during reconstructive surgery, the precise mechanism of EMR is unknown. We aim to examine the isolated effect of protonation (pH) on shape change in cartilage. Nasal septal cartilages of rabbits were mechanically deformed and placed in a rigid jig. The deformed cartilages were submerged in isotonic phosphate buffered saline baths (osm = 290 mmol/Kg) with a pH of 3 (N = 51), pH of 7 (N = 51), and a pH of 11 (N = 51) for 15 minutes. Following re-equilibration, specimens were removed from their jig and the angle change from baseline was measured using digital micrometry. Significant shape change was noted in all specimens, with an angle change of 33.6°, 33.3°, and 32.0° experienced by the pH of 3, 7, and 11 groups, respectively. Despite a trend toward increased shape change in the acidic treatment, there was no significant difference between groups. Although current evidence indicates that dynamic oxidation-reduction reactions within the extracellular matrix of cartilage may be implicated in EMR-induced shape change, when pH was isolated as a single variable it was not sufficient to produce cartilage shape change.
Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wou... more Burn and blast injuries are frequently complicated by invasive infections, which lead to poor wound healing, delay in treatment, disability, or death. Traditional approach centers on early debridement, fluid resuscitation, and adjunct intravenous antibiotics. These modalities often prove inadequate in burns, where compromised local vasculature limits the tissue penetration of systemic antibiotics. Here, we demonstrate the treatment of infected burns with topical delivery of ultrahigh concentrations of antibiotics. Standardized burns were inoculated with Staphylococcus aureus or Pseudomonas aeruginosa. After debridement, burns were treated with either gentamicin (2 mg/mL) or minocycline (1 mg/mL) at concentrations greater than 1,000 times the minimum inhibitory concentration. Amount of bacteria was quantified in tissue biopsies and wound fluid following treatment. After six days of gentamicin or minocycline treatment, S. aureus counts decreased from 4.2 to 0.31 and 0.72 log CFU/g in tissue, respectively. Similarly, P. aeruginosa counts decreased from 2.5 to 0.0 and 1.5 log CFU/g in tissue, respectively. Counts of both S. aureus and P. aeruginosa remained at a baseline of 0.0 log CFU/mL in wound fluid for both treatment groups. The findings here demonstrate that super-therapeutic concentrations of antibiotics delivered topically can rapidly reduce bacterial counts in infected full-thickness porcine burns. This treatment approach may aid wound bed preparation and accelerate time to grafting. This article is protected by copyright. All rights reserved.
Electromechanical reshaping (EMR) involves the application of an electrical current to mechanical... more Electromechanical reshaping (EMR) involves the application of an electrical current to mechanically deformed cartilage to create sustained tissue shape change. Although EMR may evolve to become an inexpensive and reliable way of producing shape change in cartilage during reconstructive surgery, the precise mechanism of EMR is unknown. We aim to examine the isolated effect of protonation (pH) on shape change in cartilage. Nasal septal cartilages of rabbits were mechanically deformed and placed in a rigid jig. The deformed cartilages were submerged in isotonic phosphate buffered saline baths (osm = 290 mmol/Kg) with a pH of 3 (N = 51), pH of 7 (N = 51), and a pH of 11 (N = 51) for 15 minutes. Following re-equilibration, specimens were removed from their jig and the angle change from baseline was measured using digital micrometry. Significant shape change was noted in all specimens, with an angle change of 33.6°, 33.3°, and 32.0° experienced by the pH of 3, 7, and 11 groups, respective...
Occult submucous cleft palate is a congenital deformity characterized by deficient union of the m... more Occult submucous cleft palate is a congenital deformity characterized by deficient union of the muscles that normally cross the velum and aid in elevation of the soft palate. Despite this insufficient muscle coverage, occult submucous cleft palate by definition lacks clear external anatomic landmarks. This absence of anatomic signs makes diagnosis of occult submucous cleft less obvious, more dependent on ancillary tests, and potentially missed entirely. Current diagnostic methodologies are limited and often are unrevealing in the presurgical patient; however, a missed diagnosis of occult submucous cleft palate can result in velopharyngeal insufficiency and major functional impairment in patients after surgery on the oropharynx. By accurately and easily diagnosing occult submucous cleft palate, it is possible to defer or modify pharyngeal surgical intervention that may further impair velopharyngeal function in susceptible patients. In this report, we introduce transillumination of the soft palate using a transnasal or transoral flexible endoscope as an inexpensive and simple technique for identification of submucous cleft palate. The use of transillumination of an occult submucous cleft palate is illustrated in a patient case and is compared to other current diagnostic methodologies.
Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular mat... more Significance: Fibroblasts play a critical role in normal wound healing. Various extracellular matrix (ECM) components, including collagens, fibrin, fibronectin, proteoglycans, glycosaminoglycans, and matricellular proteins, can be considered potent protagonists of fibroblast survival, migration, and metabolism. Recent Advances: Advances in tissue culture, tissue engineering, and ex vivo models have made the examination and precise measurements of ECM components in wound healing possible. Likewise, the development of specific transgenic animal models has created the opportunity to characterize the role of various ECM molecules in healing wounds. In addition, the recent characterization of new ECM molecules, including matricellular proteins, dermatopontin, and FACIT collagens (Fibril-Associated Collagens with Interrupted Triple helices), further demonstrates our cursory knowledge of the ECM in coordinated wound healing. Critical Issues: The manipulation and augmentation of ECM components in the healing wound is emerging in patient care, as demonstrated by the use of acellular dermal matrices, tissue scaffolds, and wound dressings or topical products bearing ECM proteins such as collagen, hyaluronan (HA), or elastin. Once thought of as neutral structural proteins, these molecules are now known to directly influence many aspects of cellular wound healing. Future Directions: The role that ECM molecules, such as CCN2, osteopontin, and secreted protein, acidic and rich in cysteine, play in signaling homing of fibroblast progenitor cells to sites of injury invites future research as we continue investigating the heterotopic origin of certain populations of fibroblasts in a healing wound. Likewise, research into differently sized fragments of the same polymeric ECM molecule is warranted as we learn that fragments of molecules such as HA and tenascin-C can have opposing effects on dermal fibroblasts.
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Papers by Lauren Tracy