Lighting the Way for Necrosis Excision Through Indocyanine Green Fluorescence-Guided Surgery.

BACKGROUND: No objective technique exists to distinguish necrotic from viable tissue, risking over-excision in burns and loss of wound healing potential. Second window indocyanine green (SWIG) is a novel fluorescence-imaging modality being studied to identify residual solid tumors during oncological surgery. SWIG has also been shown to have avidity for necrosis in animal models, but translation of these findings to humans is lacking. The objective of this study was to evaluate SWIG in the identification of burn wound necrosis and compare it with previously published indocyanine green angiography (ICGA) techniques. STUDY DESIGN: This study used mouse, human skin xenograft and human patient burn models. Brightfield and SWIG near-infrared imaging were performed on macroscopic tissue samples, which were then cryopreserved, sectioned, and analyzed for microscopic fluorescence. SWIG fluorescence findings were correlated to visual assessment of the burn wound as well as histological markers of necrosis using hematoxylin and eosin and lactate dehydrogenase stains. RESULTS: We found that SWIG identified burn necrosis in a manner dependent on the dose and timing of indocyanine green (ICG) administration and had an inverse fluorescence signal compared with ICGA. Furthermore, SWIG fluorescence identified the interface of viable and nonviable tissue. CONCLUSION: Our study confirmed that ICGA is an inconsistent and nonstandardized modality to evaluate burn injuries. In contrast, SWIG imaging is a potential imaging modality to objectively prognosticate burn wound healing potential and guide intraoperative burn excision. Further studies are needed to define ratios of fluorescence intensity values to guide surgical decision-making in burn excision and to better define how ICG is retained in necrotic tissue to enhance utility of SWIG in other disease processes.

Dental Topics for Plastic Surgeons, Part Three: Infection and Trauma of the Dentition.

ABSTRACT: Conditions that affect dental and periodontal structures receive sparse coverage in the plastic surgery literature, yet a working knowledge of this subject matter is important in certain areas of clinical practice and a fundamental understanding is part of plastic surgery competency tested on the in-service and written board examinations. This 4-part series written to provide plastic surgeons with a working knowledge of dental topics that may be relevant to their clinical practice. This section, Part III, covers inflammatory and infectious conditions of the dentition and related structures, as well as dentoalveolar trauma.

Dental Topics for Plastic Surgeons, Part Two: Abnormal Tooth Development, Conditions, and Treatment.

Conditions that affect dental and periodontal structures receive sparse coverage in the plastic surgery literature, yet a working knowledge of this subject matter is important in certain areas of clinical practice and a fundamental understanding is part of plastic surgery competency tested on the in-service and written board examinations. This four-part series written to provide plastic surgeons with a working knowledge of dental topics that may be relevant to their clinical practice. This section, Part II, covers abnormal tooth development and related conditions.

Dental Topics for Plastic Surgeons, Part One: Normal Anatomy, Growth and Development.

Normal and abnormal conditions affecting the dentition and the periodontal structures receive sparse coverage in the plastic surgery literature, textbooks, and training programs. Nevertheless, a working knowledge of this subject matter is important in certain areas of clinical practice, and a fundamental understanding is often part of plastic surgery competency tested for in the In-service and written board examinations. This four-part series is written to provide plastic surgeons with a working knowledge of relevant dental topics. Part 1 covers fundamental aspects of normal dental embryology, growth and anatomy.

Neonatal Compartment Syndrome as a Result of Thromboembolic Event.

Neonatal compartment syndrome is a rare condition characterized by progressive limb ischemia and tissue necrosis manifesting at birth or in the immediate postpartum period. Early recognition of clinical features and immediate surgical intervention offer the best prognosis, but unfamiliarity with this uncommon entity often results in delayed diagnosis and catastrophic consequences, including limb amputation. We present a case in a preterm neonate who developed a proximal arterial thrombus after sustaining limb ischemia in utero. This case demonstrated that even delayed treatment with appropriate therapy can result in salvage of the limb. Clinicians should be aware of the characteristic skin findings and institute appropriate measures to determine the presence or absence of compartment syndrome.

The roles of αV integrins in lens EMT and posterior capsular opacification.

Posterior capsular opacification (PCO) is the major complication arising after cataract treatment. PCO occurs when the lens epithelial cells remaining following surgery (LCs) undergo a wound healing response producing a mixture of α-smooth muscle actin (α-SMA)-expressing myofibroblasts and lens fibre cells, which impair vision. Prior investigations have proposed that integrins play a central role in PCO and we found that, in a mouse fibre cell removal model of cataract surgery, expression of αV integrin and its interacting ß-subunits ß1, ß5, ß6, ß8 are up-regulated concomitant with α-SMA in LCs following surgery. To test the hypothesis that αV integrins are functionally important in PCO pathogenesis, we created mice lacking the αV integrin subunit in all lens cells. Adult lenses lacking αV integrins are transparent and show no apparent morphological abnormalities when compared with control lenses. However, following surgical fibre cell removal, the LCs in control eyes increased cell proliferation, and up-regulated the expression of α-SMA, ß1-integrin, fibronectin, tenascin-C and transforming growth factor beta (TGF-ß)-induced protein within 48 hrs, while LCs lacking αV integrins exhibited much less cell proliferation and little to no up-regulation of any of the fibrotic markers tested. This effect appears to result from the known roles of αV integrins in latent TGF-ß activation as αV integrin null lenses do not exhibit detectable SMAD-3 phosphorylation after surgery, while this occurs robustly in control lenses, consistent with the known roles for TGF-ß in fibrotic PCO. These data suggest that therapeutics antagonizing αV integrin function could be used to prevent fibrotic PCO following cataract surgery.