Comparison of Photochemical Crosslinking Versus Sutures for Bonding Conjunctival Grafts
LASERS IN SURGERY AND MEDICINE
Authors: Wang, Yan; Zhu, Lu; Zhu, Jingyin; Shen, Nianci; Yao, Min; Yu, Yan
Background and Objectives To explore whether Rose Bengal-induced photochemical crosslinking (RB-PCL) can be a replacement for sutures in conjunctival autograft bonding, we compared the safety, operating time, postoperative ocular signs, and inflammatory responses of RB-PCL versus nylon suturing for sealing conjunctival autografts in rabbits. Study Design/Materials and Methods Thirty-six New Zealand White rabbits underwent limbal conjunctival autografting using either sutures or RB-PCL to attach conjunctival autografts to the bare sclera. Animals were randomized to one of two groups (18 per group): the suture group or RB-PCL group. Photochemical crosslinking with a wavelength of 532 nm green light with an illumination intensity of 0.6 W/cm(2) for 250 seconds (150 J/cm(2)) or suturing was performed followed by light examination at 3, 7, 28 days after surgery to evaluate the healing condition. Rabbits in each group were euthanized on day 3 (n = 6), 7 (n = 6), or 28 (n = 6) postoperatively, and the graft tissues from the surgical site were processed to evaluate inflammatory response by assessing protein levels of tumor necrosis factor alpha (TNF-alpha), and interleukin 6 (IL-6) as well as histological examination. Cell viability was evaluated by counting both total and dead cells on hematoxylin and eosin (H&E) stained tissue samples from both groups at 3 and 7 days after surgery. The surgery procedure time was recorded and the graft surface temperatures were measured before and after illumination. Results Photochemical crosslinking effectively secured the limbal conjunctival autograft over an ocular conjunctival defect with no significant difference from the suture group. The time required for this light activated bonding method was similar to 550 seconds in comparison with the suture method of half hour. The differences of measured temperature on the graft surface before and after RB-PCL treatment were 2.98 +/- 0.11 degrees C. The induction of IL-6 and TNF-alpha protein was remarkably reduced in the RB-PCL group compared with the suture group at 3 and 7 days after surgery. Histology revealed less infiltrated neutrophils were observed in the RB-PCL group than in the suture group at 3 and 7 days postoperatively. Furthermore, the RB-PCL group showed a better healing process with less eye discharge and mild conjunctival congestion. No significant difference in percent dead cells was observed between RB-PCL and suture groups at 3 and 7 days after surgery. Conclusions RB-PCL is a promising alternative for bonding the conjunctival autograft with shorter operation time, less inflammation and better healing outcomes compared to conventional suture. Thermal damage and phototoxicity were not observed using the RB-PCL method in bonding conjunctival grafts. Lasers Surg. Med. (c) 2019 Wiley Periodicals, Inc.
Pityriasis rosea and other infectious eruptions during pregnancy: Possible life-threatening health conditions for the fetus
CLINICS IN DERMATOLOGY
Authors: Rebora, Alfredo; Ciccarese, Giulia; Herzum, Astrid; Parodi, Aurora; Drago, Francesco
Any infectious illness presenting with an eruption in a pregnant patient may be associated with an increased risk of fetal loss. The viruses that can infect the placenta during maternal infection and can be transmitted to the fetus and cause congenital disease include the rubella virus, the measles virus, the varicella zoster virus, parvovirus B19, human cytomegalovirus, arboviruses, and hepatitis E virus type 1. In addition, some bacteria responsible for exanthematous diseases, like Treponema pallidum, can be transmitted during pregnancy from the mother to the fetus and cause fetal loss. All these infectious agents can cause typical and/or atypical exanthems whose etiologic diagnosis is sometimes difficult but important to determine, especially in pregnant women because of the potential risk to the fetus. In the last 20 years, we have extensively studied pityriasis rosea from the clinical and laboratory perspectives, demonstrating the pathogenic role of human herpesvirus (HHV)-6 and -7. We synthesize the available evidence that PR may be associated with active HHV-6/7 infection and therefore with complications during pregnancy and fetal loss. We have also summarized the emerging infectious illnesses of dermatologic interest that may represent life-threatening health conditions for the fetus: measles, rubella, arbovirus infection, and syphilis. (C) 2019 Elsevier Inc. All rights reserved.