Experimentally induced fat embolism syndrome: shift from obstruction to toxic effects

Background@#Two hypothetical mechanisms have been proposed for fat embolism syndrome: mechanical obstruction and biochemical reactions. However, it has not been proven whether these mechanisms are correlated. This study aimed to demonstrate the relationship between these two hypothetical mechanisms by observing biochemical and histological changes in animals. @*Methods@#After a preliminary study, 700 mg/kg of triolein was injected via the ear vein into 25 rabbits and hemodynamic changes in triglycerides, lipases, free fatty acids, and albumin over time were observed. Necropsies were immediately conducted on all experimental animals, and the lungs were examined histologically. @*Results@#Eight rabbits died within 1 hour after the injection due to mechanical obstruction. Six rabbits died 7–60 hours after the injection due to diffuse hemorrhage of the lung induced by the toxic biochemical reactions of free fatty acids. Histological examinations of the lungs of the surviving rabbits showed petechiae on the surfaces and evidence of recovery from hemorrhage. Blood levels of free fatty acids increased immediately after the injection of triolein. @*Conclusions@#This study revealed that fat emboli primarily injure the lung via mechanical obstruction. The fat is hydrolyzed into fatty acids and causes secondary damage via biochemical reactions. The present study sheds light on the pathophysiology of fat embolism syndrome, with possible implications for its management and prevention.

Experimentally induced fat embolism syndrome: shift from obstruction to toxic effects

Background@#Two hypothetical mechanisms have been proposed for fat embolism syndrome: mechanical obstruction and biochemical reactions. However, it has not been proven whether these mechanisms are correlated. This study aimed to demonstrate the relationship between these two hypothetical mechanisms by observing biochemical and histological changes in animals. @*Methods@#After a preliminary study, 700 mg/kg of triolein was injected via the ear vein into 25 rabbits and hemodynamic changes in triglycerides, lipases, free fatty acids, and albumin over time were observed. Necropsies were immediately conducted on all experimental animals, and the lungs were examined histologically. @*Results@#Eight rabbits died within 1 hour after the injection due to mechanical obstruction. Six rabbits died 7–60 hours after the injection due to diffuse hemorrhage of the lung induced by the toxic biochemical reactions of free fatty acids. Histological examinations of the lungs of the surviving rabbits showed petechiae on the surfaces and evidence of recovery from hemorrhage. Blood levels of free fatty acids increased immediately after the injection of triolein. @*Conclusions@#This study revealed that fat emboli primarily injure the lung via mechanical obstruction. The fat is hydrolyzed into fatty acids and causes secondary damage via biochemical reactions. The present study sheds light on the pathophysiology of fat embolism syndrome, with possible implications for its management and prevention.

Oncoplastic breast reduction using the short scar periareolar inferior pedicle reduction technique

After a partial mastectomy, large or ptotic breasts can be reconstructed using breast reduction techniques. Wise-pattern reduction is typically used to remove masses in any quadrant of the breast, but this technique leaves a large inverted T-shaped scar. Instead, the short scar periareolar inferior pedicle reduction (SPAIR) technique involves a periareolar line and does not result in a scar along the inframammary fold (IMF). A 49-year-old patient with macromastia and severely ptotic breasts was diagnosed with invasive cancer of the left breast. Her large breasts caused pain in her back, shoulders, and neck. She also expressed concern about postsurgical scarring along the IMF. In light of this concern, we chose the SPAIR technique, and we designed and performed the procedure as described by Hammond. During surgery, we removed 36 g of breast tumor and 380 g of breast parenchyma from the left breast. To establish symmetry, we also removed 410 g of tissue from the right breast. Postoperatively, the patient reported satisfaction regarding the reduction mammaplasty and, in particular, noted decreased back, shoulder, and neck pain. In summary, we used the SPAIR technique to achieve oncologic and aesthetic success in a patient with macromastia and a tumor located lateral to the nipple-areolar complex.

Retrospective review of 108 breast reconstructions using the round block technique after breast-conserving surgery: Indications, complications, and outcomes

Background@#Several oncoplastic approaches have been implemented in recent years to enhance cosmetic results and to reduce complications. The round block technique is a volume displacement technique for breast reconstruction after breast-conserving surgery (BCS). However, its indications are currently limited according to tumor location, and its cosmetic results and complications have not been clearly established. We hypothesized that the round block technique could produce favorable cosmetic results without major complications regardless of tumor location or nipple-tumor distance, below a certain resected tumor volume and tumor-breast volume ratio. @*Methods@#All breast reconstructions using the round block technique after BCS were included in this analysis. Patients’ data were reviewed retrospectively to investigate complications during follow-up, and clinical photos were used to evaluate cosmetic results. The relationships of tumor location, nipple-tumor distance, tumor volume, and the tumor-breast volume ratio with cosmetic results were investigated. @*Results@#In total, 108 breasts were reconstructed. The mean resected tumor volume was 30.2±15.0 mL. The cosmetic score was 4.5±0.6 out of 5. Tumor location, nipple-tumor distance, tumor volume, tumor-breast volume ratio, radiotherapy, and chemotherapy had no significant effects on cosmetic results or complications. There were no major complications requiring reoperation. @*Conclusions@#Breast reconstruction using the round block technique after BCS can lead to good cosmetic results without major complications regardless of the tumor location, nipple-tumor distance, radiotherapy, or chemotherapy. Below the maximum tumor volume (79.2 mL) and the maximum tumor-breast volume ratio (14%), favorable results were consistently obtained.

Malignant Hepatic Solitary Fibrous Tumor

Hepatic solitary fibrous tumors (SFTs) are mostly benign and rare because of information regarding the clinical symptoms, treatment, and prognosis of their malignant forms is currently lacking. A literature review concerning malignant SFTs revealed that there were a few cases where patients experienced abdominal right upper quadrant (RUQ) pain as their first clinical symptom, and metastases were found after being diagnosed with hepatic SFT. Here, we report a patient who was previously healthy without any clinical symptoms such as RUQ pain or weight loss, but had the appearance of a metastatic mass as the first clinical presentation before a primary hepatic SFT was detected.

Factors affecting mastectomy specimen density in direct-to-implant breast reconstruction

BACKGROUND: Direct-to-implant breast reconstruction following nipple-sparing mastectomy is becoming increasingly common. The weight of the breast specimen informs implant selection. However, specimens of the same weight may have different volume. Therefore, identifying the factors affecting the density of breast specimens may facilitate the selection of implants with an appropriate volume. METHODS: From December 2015 to May 2018, 108 patients underwent direct-to-implant reconstruction following nipple-sparing mastectomy. The weight of the breast specimens was measured using an electronic scale in the operating room. Furthermore, the volume of specimens was measured using the water displacement technique. Multiple regression analysis was performed on factors that can affect breast density, such as menopause, neoadjuvant chemotherapy (CTx), age, body mass index, and diabetes mellitus. RESULTS: The average density of breast specimens in patients older than 50 years (n=36) was 0.96±0.04 g/mL, which was significantly lower than the 1.01±0.08 g/mL observed in patients younger than 50 years (n=72) (P=0.007). The mean density of breast specimens in patients who underwent neoadjuvant CTx (n=25) was 0.96±0.06 g/mL, which was significantly lower than the value of 1.00±0.08 g/mL in those who did not (n=83). CONCLUSIONS: It is advisable to select an implant slightly larger than the mastectomy specimen weight in patients older than 50 years or in those who have undergone neoadjuvant CTx.

Treatment of post-traumatic chin deformities using bilateral botulinum toxin injections

Post-traumatic hematoma formation is a common complication of contusion. If the hematoma is large enough to aspirate or drain, it can be treated quickly and appropriately. However, if the hematoma is small or concealed by local swelling, it may be overlooked and left untreated. In most cases, a hematoma will resolve following conservative treatment; however, associated infection or muscle fibrosis can occur. Herein, we present the case of a patient with a chin deformity caused by a post-traumatic hematoma. The deformity was treated using botulinum toxin and triamcinolone acetonide injections as minimally invasive treatments. The course of treatment was good.