Analysis of Depth of Ablation,Thermal Damage, Wound Healing, and Wound Contraction With Erbium YAG Laser in a Yorkshire Pig Model.

BACKGROUND AND OBJECTIVES: The erbium YAG laser is commonly used for skin resurfacing. It is known that varying the pulse duration can influence residual thermal damage and wound healing. Our study used a porcine model to evaluate a broad range of settings in a comparison of depth of ablation, depth of residual thermal damage (RTD), and wound contraction employing both a full coverage and fractional hand piece with an erbium YAG laser. MATERIALS AND METHODS: The laser delivered an ablative pulse followed by a heating pulse of variable duration using either the full coverage or fractional hand piece. Pulse durations for specific coagulation depths were selected based on existing heat transfer models. The bilateral flanks of a single Yorkshire pig were irradiated. There were 14 treatment groups. 3 sites were treated per group for a total of 42 sites. Two of the 3 sites were for observational assessments and the 3rd site served as a reservoir for biopsies. Biopsy specimens were collected on days 0, 1, 3, 7, 14, and 28. Bleeding, erythema, wound healing, and wound contraction (in the fractional hand piece groups) were assessed. CONCLUSION: Wound healing is faster for fractional laser skin resurfacing compared with traditional contiguous resurfacing as demonstrated by textural changes and degree of erythema. The laser operator can be confident that the depth of ablation displayed on this system accurately reflects what is occurring in vivo for both confluent and fractional modes. Likewise, the measured degree of coagulation was consistent with panel display settings for the confluent mode. However, the degree of coagulation, as measured by the thickness of residual thermal damage, did not vary significantly between the fractional groups. In other words, the pulse duration of the second (heating) pulse did not impact the degree of coagulation in the fractional mode. There was a 2.3% wound contraction between some groups and a 6.5% wound contraction between other groups. A two way analysis of variance found a statistically significant difference in wound contraction based on ablation depth ( P = 0.012) but the degree of coagulation did not prove to be statistically significant for wound contraction (P = 0.66).

Rare case of acral calcified angioleiomyoma with macroscopic calcium extrusion.

Acral calcified angioleiomyoma is an uncommon tumor that presents as a non-descript papule or subcutaneous nodule, classically on the foot. Biopsy or excision is typically the diagnostic method of choice as well as the treatment for these sometimes painful tumors. We report an uncommon clinical presentation of acral calcified angioleiomyoma with considerable extrusion of calcium perforating through the skin.

Hemochromatosis and fatty liver disease: building evidence for insulin resistance in bottlenose dolphins (Tursiops truncatus).

UNLABELLED: Hemochromatosis in bottlenose dolphins (Tursiops truncatus) is associated with high postprandial plasma insulin levels, suggestive of insulin resistance. In humans, insulin resistance is associated with liver pathologies, including excessive iron deposition and nonalcoholic fatty liver disease. Dolphin liver tissues, in addition to excessive iron storage, were evaluated for other pathologies supportive of underlying insulin resistance. Archived liver tissues collected postmortem during 1985-2010 from 18 dolphins (median age 27.9 yr, range 0.7-51.4) that were part of the Navy Marine Mammal Program's managed collection were assessed for the presence and severity of hemosiderin deposition, fatty liver disease, and hepatitis. Demographics, clinical pathology values, and percentage weight loss were compared among dolphins with and without these changes. Twelve (66.7%) dolphins had mild to moderate hemosiderin deposition, 7 (38.9%) had mild to severe fatty liver disease, and 11 (61.1%) had mild to moderate hepatitis. Of the 12 dolphins with hemosiderosis, deposition occurred in the Kupffer cells among 11 (91.7%). Dolphins with fatty liver disease were more likely to have higher postprandial serum hyperglycemia (>140 mg/dl), leukocytosis (>11,000 cells/microl), and hyperglobulinemia (>3.5 g/dl). Unlike in many nonhuman terrestrial animals, fatty liver disease was not associated with rapid weight loss or hypoglycemia. Interestingly, there were no significant associations among dolphins with hemosiderosis, fatty liver disease, and hepatitis. This study supports that both hemochromatosis and fatty liver disease were present in the dolphin study population, and histopathology and clinical pathology among these animals suggest a nonhereditary, metabolic etiology. KEYWORDS: Bottlenose dolphin, fatty liver disease, hemochromatosis, hemosiderosis, hepatic lipidosis, hepatitis, Tursiops truncatus.

Synchronous onset of multiple cutaneous neuroendocrine (Merkel cell) carcinomas localized to the scalp.

Merkel cell carcinoma (MCC) is a rare aggressive neoplasm that typically presents as a solitary nodule or plaque on sun-exposed skin of the elderly. Although multiple MCC have been described, they are rare, and metastases must be excluded. We report a case of a 59-year-old white male who presented with abrupt onset of multiple small bluish papules on his frontal scalp. On low power, the tumor had the overall histological silhouette of a nodular basal cell carcinoma. However, because of the lack of an epithelial connection and the cell's cytomorphological features, a MCC was considered and was subsequently confirmed using immunohistochemical stains. The MCC described in this report is unusual in that it presented as multiple cutaneous lesions that arose synchronously, along with micrometastases to sentinel lymph nodes.

Atypical cutaneous myeloid infiltrate in myelodysplastic syndrome: a case report.

We report the case of a 31-year-old man with an atypical myeloid dermal infiltrate manifested by a 1.5-year history of recurrent erythematous plaques over his body that previously were shown to be culture positive for Staphylococcus aureus and had responded well to oral antibiotic treatment. The ultimate diagnosis was refractory anemia with excess blasts-2 (RAEB-2), a myelodysplastic syndrome (MDS). Whether it is a specific or nonspecific lesion, cutaneous involvement in MDS is a poor prognostic factor. Leukemia cutis (LC), a specific dermal infiltrate of malignant hematopoietic cells, particularly is associated with progression to acute leukemia. However, the pathology of our patient's lesions revealed a more sparse sprinkling of atypical mononuclear cells indicative of an inflammatory recruitment of leukemic cells to the dermis. Nonetheless, the guarded prognosis of this high-risk subtype of MDS mandates continued monitoring for development of LC and progression to leukemia.

Cutaneous squamous cell carcinoma: a comprehensive clinicopathologic classification--part two.

Cutaneous squamous cell carcinoma (SCC) includes many subtypes with widely varying clinical behaviors, ranging from indolent to aggressive tumors with significant metastatic potential. However, the tendency for pathologists and clinicians alike is to refer to all squamoid neoplasms as generic SCC. No definitive, comprehensive clinicopathological system dividing cutaneous SCCs into categories based upon their aggressiveness has yet been promulgated. Therefore, we have proposed the following based upon the malignant potential of SCC variants, separating them into categories of low (< or = 2% metastatic rate), intermediate (3-10%), high (greater than 10%), and indeterminate behavior. Low-risk SCCs include SCC arising in actinic keratosis, HPV-associated SCC, tricholemmal carcinoma, and spindle cell SCC (unassociated with radiation). Intermediate-risk SCCs include adenoid (acantholytic) SCC, intraepidermal epithelioma with invasion, and lymphoepithelioma-like carcinoma of the skin. High-risk subtypes include de novo SCC, SCC arising in association with predisposing factors (radiation, burn scars, and immunosuppression), invasive Bowen's disease, adenosquamous carcinoma, and malignant proliferating pilar tumors. The indeterminate category includes signet ring cell SCC, follicular SCC, papillary SCC, SCC arising in adnexal cysts, squamoid eccrine ductal carcinoma, and clear-cell SCC. Subclassification of SCC into these risk-based categories, along with enumeration of other factors including tumor size, differentiation, depth of invasion, and perineural invasion will provide prognostically relevant information and facilitate the most optimal treatment for patients.

Cutaneous squamous cell carcinoma: a comprehensive clinicopathologic classification. Part one.

Cutaneous squamous cell carcinoma (SCC) includes many subtypes with widely varying clinical behaviors, ranging from indolent to aggressive tumors with significant metastatic potential. However, the tendency for pathologists and clinicians alike is to refer to all squamoid neoplasms as generic SCC. No definitive, comprehensive clinicopathological system dividing cutaneous SCCs into categories based upon their aggressiveness has yet been promulgated. Therefore, we have proposed the following based upon the malignant potential of SCC variants, separating them into categories of low (< or = 2% metastatic rate), intermediate (3-10%), high (greater than 10%), and indeterminate behavior. Low-risk SCCs include SCC arising in actinic keratosis, HPV-associated SCC, tricholemmal carcinoma, and spindle cell SCC (unassociated with radiation). Intermediate-risk SCCs include adenoid (acantholytic) SCC, intraepidermal epithelioma with invasion, and lymphoepithelioma-like carcinoma of the skin. High-risk subtypes include de novo SCC, SCC arising in association with predisposing factors (radiation, burn scars, and immunosuppression), invasive Bowen's disease, adenosquamous carcinoma, and malignant proliferating pilar tumors. The indeterminate category includes signet ring cell SCC, follicular SCC, papillary SCC, SCC arising in adnexal cysts, squamoid eccrine ductal carcinoma, and clear-cell SCC. Subclassification of SCC into these risk-based categories, along with enumeration of other factors including tumor size, differentiation, depth of invasion, and perineural invasion will provide prognostically relevant information and facilitate the most optimal treatment for patients.

Effect of monopolar radiofrequency treatment over soft-tissue fillers in an animal model: part 2.

BACKGROUND AND OBJECTIVE: Monopolar radiofrequency (RF) treatment is used by physicians to heat skin and promote tissue tightening and contouring. Cosmetic fillers are used to soften deep facial lines and wrinkles. Patients who have had dermal fillers implanted may also benefit from or are candidates for monopolar RF skin tightening. This study examined the effect of RF treatment on various dermal filler substances. This is the second part of a two-part study. STUDY DESIGN/MATERIALS AND METHODS: A juvenile farm pig was injected with dermal fillers including cross-linked human collagen (Cosmoplast), polylactic acid (PLA) (Sculptra), liquid injectable silicone (Silikon 1000), calcium hydroxylapatite (CaHA) (Radiesse), and hyaluronic acid (Restylane). Skin injected with dermal fillers was RF-treated using a 1.5-cm2 treatment tip and treatment levels typically used in the clinical setting. Fillers were examined histologically 5 days, 2 weeks, or 1 month after treatment. Histological specimens were scored for inflammatory response, foreign body response, and fibrosis in order to assess the effect of treatment on early filler processes, such as inflammation and encapsulation. RESULTS: Each filler substance produced a characteristic inflammatory response. No immediate thermal effect of RF treatment was observed histologically. RF treatment resulted in statistically significant increases in the inflammatory, foreign body, and fibrotic responses associated with the filler substances. CONCLUSIONS: Monopolar RF treatment levels that are typically used in the clinical setting were employed in this animal study. RF treatment resulted in measurable and statistically significant histological changes associated with the various filler materials. Additional clinical and histological studies are required to determine the optimal timing of monopolar RF treatment and filler placement for maximal potential aesthetic outcome.

Evaluation of single versus multiple cryogen spray cooling spurts on in vitro model human skin.

Many commercially available dermatologic lasers utilize cryogen spray cooling for epidermal protection. A previous tissue culture study demonstrated that single cryogen spurts (SCS) of 80 ms or less were unlikely to cause cryo-injury in light-skinned individuals. More recently, multiple cryogen spurts (MCS) have been incorporated into commercial devices, but the effects of MCS have not been evaluated. The aim was to study an in vitro tissue culture model and the epidermal and dermal effects of SCS vs patterns of shorter MCS with the same preset total cryogen delivery time (Deltat(c)) and provide an explanation for noted differences. Four different spurt patterns were evaluated: SCS: one 40-ms cryogen spurt; MCS2: two 20-ms cryogen spurts; MCS4: four 10-ms cryogen spurts; MCS8: eight 5-ms cryogen spurts. Actual Deltat(c) and total cooling time (Deltat(Total)) were measured for each spurt pattern. RAFT tissue culture specimens were exposed to cryogen spurt patterns and biopsies were taken immediately and at days 3 and 7. Actual Deltat(c) was increased while Deltat(Total) remained relatively constant as the preset Deltat(c) of 40 ms was delivered as shorter MCS. Progressively more epidermal damage was noted with exposure to the MCS patterns. No dermal injury was noted with either SCS or MCS. For a constant preset Deltat(c) of 40 ms, delivering cryogen in patterns of shorter MCS increased the actual Deltat(c) and consequently the observed epidermal cryo-injury as compared to an SCS.

Metaplastic breast carcinoma histologically mimicking cutaneous spindle cell squamous cell carcinoma.

Squamous cell carcinoma is one of the most common primary cutaneous carcinomas but on rare occasion, metastatic squamous cell carcinoma from a distant site or solid organ can present as a cutaneous lesion. Most metastases occur as dermal nodules or involve the dermal lymphatics, but when they are intimately associated with the epidermis, distinguishing the lesion as primary or metastatic may be extremely difficult and usually requires a clinical history or high index of suspicion. A 71-year-old woman presented with multiple eruptive nodules over her chest, flank, and back. Histologically the lesions appeared to be arising from the surface epithelium and consisted of atypical, predominantly spindle cells, some of which streamed off of the epidermis. Following the initial evaluation, a history of breast carcinoma with subsequent radiation therapy and ultimate mastectomy was obtained, and the original breast biopsy and mastectomy material was reviewed. After performing additional studies, it became clear that the origin of the carcinomas was metastatic from an underlying metaplastic breast carcinoma.

Adventitial cystic disease of the axillary artery.

Adventitial cystic disease (ACD) is an extremely rare cause of arterial and venous insufficiency, with only 317 reported cases in the world literature. These lesions have been previously described in the popliteal fossa, external iliac artery, and distal brachial, radial, and ulnar arteries as well as in the proximal saphenous vein at the ankle. We describe here the first reported case of this disease in a proximal vessel, the axillary artery. A 33-year-old man was evaluated for upper extremity arterial insufficiency and was diagnosed with ACD on the basis of physical examination and radiographic findings, which was confirmed by pathological assessment. The patient was treated by excision of the lesion and interposition vein bypass. As this represents the first case of ACD in the proximal vasculature, it demonstrates that these lesions can occur in axial blood vessels.