A 9-month-old 218-kg (480-lb) miniature Hereford show heifer was evaluated at the Iowa State University LVMC for an expansile mass affecting the right inferior eyelid. The owner first noticed a small wart-like mass of unspecified size at that location 3 months prior to examination at the LVMC. At that time, the owner used blunt traction to remove the mass, which was not submitted for histologic evaluation. The heifer received no other treatments prior to its examination at the LVMC.
The heifer had a body condition score of 4/5. Results of the initial physical examination were unremarkable aside from the presence of a firm, ulcerated, pedunculated mass on the right inferior eyelid. The mass measured 10 cm at its maximal vertical limit and 8 cm at its maximal horizonal limit and extended from the medial quarter of the inferior eyelid to beyond the lateral canthus (Figure 1). A complete ophthalmic examination, including slit-lamp biomicroscopy, direct ophthalmoscopy, and fluorescein staining of the cornea, was performed. The base of the mass was ≥ 3 mm ventral to the right inferior eyelid margin, but the mass contacted the corneal surface owing to its large size and pedunculated nature. A fine-shaved woodchip (foreign body) was adhered to the corneal surface in the ventrolateral quadrant of the right eye, trapped between the mass and globe. After gentle removal of the foreign body, a 4-mm superficial corneal ulcer with minor vascularization was identified underneath it. The remainder of the ophthalmic examination was unremarkable for both eyes.
Photographs of the dorsorostral (A) and lateral (B) aspects of a firm, ulcerated, pedunculated mass on the right inferior eyelid of a 9-month-old 218-kg (480-lb) miniature Hereford heifer after four 6-mm punch biopsy specimens were obtained for histologic examination at multiple locations along the periphery and center of the mass. The mass measured 7.4 × 6.7 cm at its base and extended from the medial quarter to beyond the lateral canthus. The surface of the mass was in contact with the ventrolateral quadrant of the cornea. Histologic findings for the biopsy specimens were consistent with fibrosarcoma. Each biopsy site was sutured closed, and the sutures are evident in the photographs.
Citation: Journal of the American Veterinary Medical Association 257, 8; 10.2460/javma.257.8.833
A 6-mm punch biopsy instrument was used to obtain 4 biopsy specimens from multiple locations at the periphery and center of the mass, which were submitted for histologic examination. While waiting for the histologic results of the biopsy specimens, the heifer received meloxicam (1 mg/kg [0.45 mg/lb], PO, once daily) for analgesia, and neomycin-polymyxin B-bacitracin ophthalmic ointment was topically applied to the right eye 3 times daily to prevent secondary infection of the corneal ulcer and provide lubrication to minimize friction between the mass and corneal surface. Histologic findings for the biopsy specimens were consistent with fibrosarcoma.
The decision was made to surgically remove the mass, with care taken to preserve eyelid function. In preparation for surgery, the heifer was administered tulathromycin (2.5 mg/kg [1.1 mg/lb], SC) as a perioperative antimicrobial and butorphanol (0.04 mg/kg [0.018 mg/lb], IV) for sedation and analgesia. Anesthesia was induced with 340 mL of triple drip (50 g of glyceryl guaiacolate, 1 g of ketamine, and 50 mg of xylazine in 1 L of 5% dextrose solution) IV and maintained with isoflurane in oxygen following orotracheal intubation. The heifer was positioned in left lateral recumbency. The area around the eyelid mass was aseptically prepared in a routine manner. The base of the mass, as measured by surgical calipers, was 7.4 × 6.7 cm. It spanned approximately 75% of the length of the inferior eyelid and extended past the lateral canthus. A tissue marker was used to delineate 1- to 1.5-cm margins around the base of the mass, except for the region adjacent to the eyelid margin where 1- to 3-mm margins were delineated, ensuring that there would be at least 2 mm between the surgical margin and the eyelid margin (ie, not crossing the haired-nonhaired junction of the eyelid) to preserve normal eyelid structure and function.
A CO2 lasera was used to incise the skin and provide hemostasis along the marked margins of the mass. The mass, including 1 fascial plane subjacent to it, was removed en bloc by blunt and sharp dissection with Mayo scissors. The resulting skin wound measured approximately 10 × 8.5 cm (Figure 2). To ablate any remaining neoplastic cells, laser energy was diffusely applied to the exposed wound surface by use of a wide-ablation paintbrush laser tip (beam diameter, 3 mm) attached to the CO2 laser, which was set to deliver 8 to 10 W of power in continuous mode as previously described.1,2 The medial and central portions of the surgical wound underwent primary closure by undermining the surrounding skin and placing walking sutures in the subcutaneous tissue with size-0 polyglactin 910 suture, followed by a simple continuous pattern within the subcutaneous and subcuticular layers with 2-0 polyglactin 910 suture. This left a 4.6 × 2.6-cm open wound at the dorsolateral portion of the surgical site. A lyophilized equine amnion multilayered sheetb was trimmed to fit in the remaining wound, rehydrated in sterile saline (0.9% NaCl) solution for 1 minute, placed within the wound bed, and sutured along the deep edges of the subcutaneous tissue with 4-0 polyglactin 910 suture in a simple continuous pattern. Subsequently, 2 separate sheets of 4-ply porcine SISc were trimmed to fit the wound and rehydrated in sterile saline solution for 1 minute. The first sheet of porcine SIS was placed over the equine amnion graft and sutured to the subcutaneous tissue with 3-0 polyglactin 910 suture in a simple continuous pattern. The second sheet of porcine SIS was placed over the first sheet and sutured to the subcuticular tissue with 3-0 polyglactin 910 suture in a simple continuous pattern.
Intraoperative photographs of the area surrounding the right eye of the heifer of Figure 1 following surgical resection of a fibrosarcoma on the inferior eyelid (A) and after the medial and central portions of the surgical wound underwent primary closure and a lyophilized equine amnion multilayered sheet and 2 separate sheets of 4-ply porcine SIS were sutured in place over the remaining 4.6 × 2.6-cm open wound bed (B). Histologic evaluation of the surgical margins of the mass suggested that the neoplasia was completely extirpated.
Citation: Journal of the American Veterinary Medical Association 257, 8; 10.2460/javma.257.8.833
The heifer recovered from anesthesia with no complications. Postoperative analgesia was achieved with butorphanol (0.05 mg/kg [0.023 mg/lb]), which was administered IV at extubation and then IM every 6 hours for the first 24 hours after surgery. Additionally, the heifer received meloxicam (1 mg/kg, PO, q 48 h) and tulathromycin (2.5 mg/kg, SC, once weekly) for 3 weeks. Neomycin-polymyxin B-bacitracin ophthalmic ointment was topically applied to the right eye and wound surface every 8 hours. To prevent desiccation of the biological graft, artificial tear ointment was topically applied to the surgical wound every 8 hours, 4 hours after each application of the neomycin-polymyxin B-bacitracin ointment. The heifer remained hospitalized for 1 week after surgery to ensure that the surgical wound was kept clean and frequently moistened. The superficial corneal ulcer healed without complication within 1 week after surgery. Following hospital discharge, prescribed treatment included continued alternating topical application of the neomycin-polymyxin B-bacitracin and artificial tear ointments to the surgical wound every 4 hours and application of artificial tear ointment onto the right eye every 8 hours to protect the exposed chemotic conjunctiva (Figure 3).
Photographs of the area surrounding the right eye of the heifer of Figure 1 at various times after complete surgical resection of a large fibrosarcoma from the inferior eyelid. A—At the time of hospital discharge 1 week after surgery, moderate postoperative swelling around the surgery site and chemosis of the inferior palpebral conjunctiva were present. The surgical wound and biological scaffolds were kept moist by alternating topical application of neomycin-polymyxin B-bacitracin and artificial tear ointments every 4 hours. B—Three weeks after surgery, there was a 3.5 × 2-cm firm black eschar over the surgical wound surrounded by normal-appearing skin. The sutures holding the biological scaffold in place appeared to be intact. Mild ectropion at the lateral aspect of the inferior eyelid and mild chemosis of the inferior palpebral conjunctiva were present. C—At 9 weeks after surgery, a residual 2-mm-diameter eschar and minor scar were present near the ventral aspect of the lateral canthus, but the remainder of the surgical wound area was covered with normal-appearing haired skin. Mild ectropion at the lateral aspect of the inferior eyelid was still present, but the palpebral conjunctiva was not inflamed and blinking was not compromised. D—At 8 months after surgery, only a minor scar was present at the surgery site. The ectropion at the lateral aspect of the inferior eyelid appeared to have progressed, but corneal and palpebral conjunctival health and function remained satisfactory.
Citation: Journal of the American Veterinary Medical Association 257, 8; 10.2460/javma.257.8.833
Histologic examination of the mass confirmed that clean surgical margins (ie, complete surgical excision) were achieved. However, there was scarce normal tissue between the neoplastic cells and surgical margin at the dorsal aspect of the mass adjacent to the eyelid margin.
The heifer was reevaluated 3 weeks after surgery. A firm black eschar was present over the surgical wound bed, and the sutures holding the biological scaffolds appeared to be intact (Figure 3). The eschar was 3.5 × 2 cm in size and surrounded with normal-appearing skin. There was mild ectropion at the lateral aspect of the inferior eyelid and mild chemosis of the palpebral conjunctiva of the right eye; however, the cornea was completely covered with each blink of the eyelids. All medications were discontinued at that time.
Reevaluation of the heifer 9 weeks after surgery revealed a residual 2-mm-diameter eschar and minor scar near the lateral canthus of the right eye; otherwise, the surgical wound was covered with normal-appearing haired skin (Figure 3). Mild ectropion at the lateral aspect of the right inferior eyelid was still present, but it did not appear to be compromising the health of the cornea or palpebral conjunctiva.
Eight months after surgery, the ectropion of the right inferior eyelid had progressed, but the eyelids remained functional with no clinical signs (eg, ocular discharge, conjunctivitis, or exposure keratitis) associated with the ectropion. Acceptable cosmesis had been achieved (Figure 3). Surgery to correct the ectropion was offered to the owner but was declined owing to the lack of clinical signs associated with the condition, owner's satisfaction with the cosmetic outcome, and the fact that the heifer had successfully returned to a show career. The owner was contacted by telephone 21 months after surgery and reported no change in the heifer's status or evidence of mass recurrence.
Discussion
The aim of any blepharoplasty procedure is to create or preserve an eyelid with a smooth hairless margin capable of functional blinking with minimal scarring or distortion of the face,3,4 and the aim of any neoplastic resection is to obtain adequate surgical margins without compromising function. Although eyelid masses are often observed in cattle and other species, the veterinary literature contains few descriptions for surgical excision of eyelid neoplasia in bovid species. Descriptions for surgical resection of eyelid neoplasia in cattle are limited to 2- and 4-sided wedge resections, H-blepharoplasty, and the Cutler-Beard (bucket handle) full-thickness graft.5–9 In 1 case series,6 12 of 14 cattle with squamous cell carcinoma or papilloma masses that affected 5 to 6 cm of an eyelid margin had satisfactory eyelid function following tumor resection by H-blepharoplasty. In other species, additional reconstructive blepharoplasty procedures described for resection of eyelid masses that involve a third or greater proportion of an eyelid margin include the Mustardé rotational skin graft (ie, semicircular flap), Landlot sliding outer eyelid margin graft, Whittaker lip-to-eyelid rotational flap (ie, subdermal plexus flap), Huber free tarsomarginal autograft (dogs and cats),3–5,10 and Blanchard rhomboid blepharoplasty (horses).11 Some modifications of those procedures have also been described and vary depending on the size and location of the mass.12,13
For the heifer of the present report, although a sliding or rotational skin graft without preservation of the natural eyelid margin was an option for resection of the inferior eyelid mass, we chose to resect the mass and use a combination of primary closure and 2 different types of ECM scaffolds (ie, lyophilized equine amnion multilayered sheet and 4-ply porcine SIS grafts) for secondary wound healing because it precluded the need for extensive tissue dissection to create a large skin flap. Compared with the facial skin of many small animal species, the facial skin of cattle, horses, and other large animal species is fairly immobile, inelastic, and tightly adhered to the underlying fascia, which limits donor tissue availability for closing eyelid defects and increases the risk of graft dehiscence secondary to tension.5 For example, use of an H-blepharoplasty for the heifer of this report would have required extensive dissection of tightly adhered skin around the right eye to mobilize a large section of tissue for closure of the eyelid defect. Additionally, the overall time required for the blepharoplasty procedure described for the heifer of this report was less than that required for skin grafts, some of which require 2 separate surgical procedures.3,4 The use of ECM scaffolds to assist with secondary healing of the large surgical wound in the heifer of this report allowed us to achieve adequate surgical margins around the tumor while preserving the integrity of the eyelid margin in a single fairly simple surgical procedure.
The cost of the ECM scaffolds used in the heifer of the present report represented 10% of the overall bill. Thus, the use of ECM scaffolds may be cost prohibitive for some patients. However, for this patient, we believed that the cost of the ECM scaffolds was equal to or less than the additional anesthesia and surgery costs that would been incurred had a longer sliding or rotating graft procedure been performed.
We also believed that the use of ECM scaffolds would reduce the risk for anesthesia-related morbidity and minimize tissue trauma.
Fibrosarcomas tend to be locally invasive; therefore, surgical margins of 2 to 3 cm are typically recommended during resection.14 For the heifer in this report, given the location of the tumor and limited mobility of the tissue surrounding it, our goal was to have surgical margins of at least 1 cm, which, unfortunately, could not be achieved along the dorsal border of the mass, adjacent to the inferior eyelid margin. A risk associated with narrow surgical margins during resection of a fibrosarcoma is incomplete removal of neoplastic cells resulting in tumor recurrence and the need for additional surgery. Because we were unable to ascertain the completeness of the surgical margins achieved during the intraoperative period, adjunct laser therapy was applied to the surgical wound to destroy or prevent the spread of any remaining neoplastic cells. The CO2 laser emits light that is absorbed by tissues and converted to heat energy. The paintbrush laser tip used facilitates coagulation of blood and seals small capillaries and lymphatics, which is believed to prevent tumor cells from spreading.2 However, judicious use of laser therapy is recommended because excessive thermal tissue damage can delay healing.2 Although the potential for tumor recurrence in the absence of adjunct laser therapy was unknown for the heifer of the present report, the fact that the tumor did not recur suggested that laser therapy might have assisted in the control of focal micrometastases.
Extracellular matrices have been used in many clinical applications to repair and reconstruct tissue, such as fascia, bladder, blood vessels, tendons, cornea, and skin. Multiple sources of ECMs have been used for corneal reconstruction in veterinary patients, including porcine SIS, bladder submucosa, and equine amnion.15–17 Most reports18–20 describing the use of ECM scaffolds for skin wounds in veterinary medicine are limited to experimental models of wound healing in dogs. However, in a case series21 of 4 birds, use of porcine SIS grafts to repair skin defects resulted in return to function and regrowth of feathers with minimal wound management in all 4 birds, similar to the healing with haired skin in the heifer of this report. A porcine SIS graft has also been successfully used for eyelid reconstruction in a horse.d
Advantages associated with the use of ECM scaffolds as a regenerative approach to wound closure include off-the-shelf availability, inherent antibacterial properties, and a potential reduction in surgery time, improved wound healing, and cost effectiveness relative to other procedures for wound management.22,23 One of the authors (GBS) of this report has years of clinical experience working with both equine amnion and porcine SIS grafts and believed that, for the heifer of the present report, use of an equine amnion graft in combination with porcine SIS grafts would result in superior wound healing, compared with the use of either type of graft alone. Amnion is rich in growth factors, with lyophilized amnion containing 57 proteins specifically for the regulation of inflammation, angiogenesis, and tissue regeneration.24 Amnion promotes angiogenesis, modulates inflammation and reconstruction of organized tissue,24,25 and decreases fibrosis through suppression of activated fibroblast proliferation and dedifferentiation of previously differentiated myofibroblasts responsible for wound contraction back to fibroblasts.26 The multi-layered lyophilized equine amnion graft used in this report was only 9 μm thick when dehydratede and provided little structural support for the large wound. Compared with the equine amnion graft, each 4-ply sheet of porcine SIS graft was 200 μm thick.27 Porcine SIS has also been reported to release a similar array of growth factors as amnion, which may help with wound healing.22 The placement of 2 sheets of 4-ply porcine SIS superficial to the equine amnion graft provided an external dressing to protect the thin and fragile amnion from damage and desiccation. Additionally, porcine SIS contains high concentrations of collagen type I, making it an excellent framework for organized tissue regeneration, and the use of multiple layers of porcine SIS increases the durability of the wound closure and slows graft decay,27 all of which were considered beneficial for closure of the large surgical wound in the heifer of the present report.
Potential complications associated with the use of ECM scaffolds for dermal applications include wound contraction, infection, delayed vascularization, fluid accumulation under the graft, and scarring.28 Minimizing wound contraction is desirable for optimal cosmesis and to maintain function. For the heifer of this report, minimal wound contraction was observed during the initial healing phases, but contraction increased as the wound continued to remodel, which increased the extent of ectropion in the inferior eyelid. Results from experimental studies19,20,29,30 of wound healing in animals indicate that use of amnion or SIS scaffolds generally leads to less contracture of full-thickness dermal wounds than does second-intention wound healing alone, which is desirable in some anatomic locations and following certain surgical procedures, such as blepharoplasties. Given the size of the surgical wound for the heifer of the present report, we believed that the use of ECM scaffolds resulted in less wound contracture than would have occurred had the wound been allowed to heal by second intention alone. However, further assessment of the use of ECM grafts for similar applications is necessary to validate that theory. The reason for the delayed tissue contracture observed for the heifer of this report was unknown.
For the heifer of the present report, the color of the ECM graft darkened over time and took on the appearance of an eschar. A similar phenomenon was observed in birds treated with porcine SIS grafts21 and was suspected to be a consequence of coagulated blood and serum within and under the graft matrix. The change in the outer appearance of the ECM grafts was not associated with any complications and did not appear to delay healing. Although fluid accumulation underneath or within the ECM grafts did not appear excessive for the heifer of the present report or the birds of the other report,21 further investigation is warranted to determine whether placement of fenestrations in ECM grafts might be beneficial for minimizing excessive postoperative fluid accumulation, as has been described in a previous experimental study.18
The exact duration required for complete healing of the surgical wound was unknown for the patient in this report because the heifer was not evaluated between 3 and 9 weeks after surgery owing to geographic and financial constraints. The apparent healing rate of the surgical wound for the heifer of this report (up to 9 weeks) was similar to that observed in birds in which porcine SIS grafts were used to repair skin defects (6 weeks).21 The healing rate for large wounds (2 to 4 cm in diameter) treated with SIS grafts may be slower than that for wounds allowed to heal by second intention alone owing to a decrease in wound contracture,20,29 but no difference between wound healing rate and contracture has been observed with small wounds (< 8 mm in diameter).18 For wounds treated with ECM scaffolds, regardless of the healing rate, the ECM scaffold is generally replaced with well-organized host tissue and the quality of the wound repair is considered more than adequate.22,31
Although human patients have reportedly developed immunogenic reactions to ECM grafts, the risk of immunogenic responses to ECM grafts following decellularization is low because collagen is a highly conserved protein across species.32–34 There are various ways to decellularize and sterilize ECM products, and some ECM products used in human medicine appear to be more immunogenic than others because of variable amounts of DNA remaining in those products.34,35 Comparable studies have not been performed for veterinary species. No gross evidence of rejection was observed in the heifer of this report, but histologic evaluation for immunogenic reactions or rejection was not performed.
For the heifer of the present report, healing of a large (10 × 8.5-cm) surgical wound resulting from resection of a fibrosarcoma from the right inferior eyelid was successfully achieved with a combination of primary wound closure and use of 2 different types of ECM grafts to facilitate second-intention healing. On the basis of results for the heifer of this report and other clinical reports involving birds21 and a horse,d as well as our previous clinical experience, we believe that ECM grafts represent a promising modality for closure of large dermal wounds by facilitating growth of healthy tissue and decreasing skin contracture and fibrosis. To our knowledge, the present report was the first to describe the use of a combination of lyophilized equine amnion and porcine SIS grafts to repair a large skin defect. The surgical technique described obviated the need for an extensive skin flap and may be particularly beneficial for blepharoplasty procedures where preservation of an eyelid margin is desired. Further studies including multiple animals of various species are necessary to validate the viability of a combined ECM approach for wound healing and blepharoplasty procedures in veterinary medicine.
Acknowledgments
No third-party funding or input were received in connection with surgical planning or the writing or publication of this report. The authors declare that there were no conflicts of interest.
Anicell Biotech, Chandler, Ariz, provided the lyophilized equine amnion graft material used for this heifer.
ABBREVIATIONS
| ECM | Extracellular matrix |
| LVMC | Lloyd Veterinary Medical Center |
| SIS | Small intestinal submucosa |
Footnotes
LuxarCare, Aesculight, Woodinville, Wash.
EquusCell StemWrap, Anicell Biotech, Chandler, Ariz.
BioSIS Bioscaffold multilayer, Vetrix Plus, Cumming, Ga.
Leiva M, Pena M. Major eyelid reconstruction in horses: techniques and outcome (abstr), in Proceedings. Dorothy Havemeyer Found Equine Ophthalmol Symp 2011; 14.
Ames B, Anicell Biotech, Chandler, Ariz: Personal communication, 2019.
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