Carcinoma de células escamosas corneal em um cão - uso da Mitomicina C 0, 02% como adjuvante no tratamento / Corneal squamous cell carcinoma in a dog - use of Mitomycin C 0. 02% as an adjuvant therapy

Background: Although Squamous Cell Carcinoma (SCC) is most commonly seen in the epidermis, this malignant neoplasm can manifest in various other tissues. A wide range of factors may be related to the development of SCC in the cornea, with continuous exposure to ultraviolet radiation and chronic friction to the ocular surface being the most accepted theories. In addition to surgical procedures, the use of mitomycin C in the topical treatment of corneal SCC has shown good results in therapeutic management. Thus, the objective of the current work is to report the satisfactory response observed in the use of mitomycin C in a case of SCC in the cornea of a dog. Case: A 9-year-old male Pug dog was attended by the Veterinary Ophthalmology and Microsurgery Sector (SOMVET) of the University Veterinary Hospital (HVU) of the Federal University of Santa Maria (UFSM) with Squamous Cell Carcinoma (SCC) in the cornea of the left eye, which had recurred after a previous surgical intervention. Secretion and discomfort in the left eye were noted during clinical examination. In addition, both eyes presented pigmentary keratitis in the medial corner. Surgical excision of the neoplasm was performed using the surgical technique of anterior lamellar keratectomy. In the immediate postoperative period, topical therapy was started with eye drops based on mitomycin C at 0.02%, for a period of 28 consecutive days. The use of this chemotherapy drug in the topical form was intended to minimize the chances of recurrence of the clinical condition, since the patient is predisposed to this alteration. In addition, supportive therapy was implemented to improve patient comfort, consisting of the use of tobramycin-based eye drops (6 times a day, for 14 days), atropine 1% eye drops (BID, for 3 days), lubricating eye drops based on sodium hyaluronate (3 times a day, for continuous use), and immunomodulatory eye drops based on tacrolimus 0.02% (twice a day, for continuous use). The patient was evaluated 7, 14, 21, and 28 days after surgery, when good results were observed. One year after treatment, the dog was still showing no signs of recurrence of the treated clinical condition. Discussion: It is known that chronic friction on the surface of the cornea predisposes to the diagnosis of corneal SCC. Accordingly, in the clinical examination of the patient in this report, the presence of bilateral pigmentary keratitis was observed, an alteration that leads to a framework of chronic aggression to the cornea. Surgical treatment is recommended to remove the tumor mass in the ocular region. However, in cases of corneal SCC, the literature highlights that recurrence after surgical excision is a common factor. As the patient in this study arrived at the clinic with a history of recurrence, topical therapy with mitomycin C associated with surgical treatment was instituted. This chemotherapy drug has shown encouraging results in the treatment of some neoplasms, especially SCC. Its use in this case supported previous findings, pointing to a satisfactory result in which the patient had no recurrences after one year of follow-up. In addition, the concentration and frequency used of the active ingredient did not lead to adverse effects in the short or medium term.

Persistência do vítreo primário hiperplásico e catarata em cão / Persistence of hyperplastic primary vitreous and cataract in a dog

Background: Persistent hyperplastic primary vitreous is a rare ocular condition that is usually unilateral, formed when normal regression of the hyaloid vascular system does not occur. Diagnosis is possible through ultrasonography, by obtaining images that provide information and also serve as a differential diagnosis. Clinically the condition presents with signs of leukocoria, microphthalmia, and cataracts, and it can be further classified into 6 degrees according to the evolution. The objective of this work is to describe the case and treatment of a canine of the Pointer breed that presented opacity in both eyes, with diagnosis confirmed through ocular ultrasonography. Case: A 6-year-old male pointer dog, weighing 27 kg, was referred to the Veterinary Medical Teaching Hospital of the Federal University of Santa Maria (UFRGS), Santa Maria, RS - Brazil with a history of blindness. According to the owner, the animal's right eye has always been "white", since it was a puppy and the left eye began to present the same characteristic a short time ago. On ophthalmological examination, neither eye showed signs of ocular discomfort, the Schirmer's tear test was within the range expected for the species, fluorescein and threat tests were negative, and a positive pupillary reflex was observed in the left eye. The right eye had total corneal opacity associated with a chronic lesion and the presence of pigment cells in the medial portion of the eyeball, the opacity making it impossible to visualize the other internal structures of the eyeball. The left eye presented lens opacity. In the ultrasound of the right eye, there were several alterations, the presence of a triangular-shaped hyperechogenic structure in the vitreous chamber, a decrease in the depth of the anterior chamber, and the presence of abnormality in the development of the lens. The findings are compatible with and confirmed the diagnosis of PHPV. In the left eye, the ultrasound images indicated hyperechogenicity of the posterior and anterior poles of the lens, findings compatible with cataracts. Through the animal's history, complete ophthalmic examination, and use of ocular ultrasonography, it was possible to diagnose and differentiate the causes of the white eye in the patient. The preoperative screening was continued with an electroretinography examination, which showed a satisfactory electrical response for the retina of the left eye and an unsatisfactory electrical response for the retina of the right eye. Phacoemulsification surgery was performed to remove the cataract in the left eye with intraocular lens implantation. The positive threat reflex returned in this eye, with a return of visual acuity. Discussion: Persistent hyperplastic tunica lentis and persistent hyperplastic primary vitreous (PHTVL/PHPV) are congenital anomalies caused by a failure to regress the fetal hyaloid vasculature. These conditions are not common, but occur sporadically in dogs. The PHPV classification can be classified into degrees, based on the morphological aspect of the lesion. Following this classification scheme, the PHPV of the animal in question refers to the 6th degree of evolution. The total opacity of the cornea in the right eye was associated with the presence of a hyperplastic primary vitreous and the leukocoria in the left eye was due to the presence of a mature cataract. The conclusion of the diagnosis was only possible through ocular ultrasonography, which is very useful to differentiate the causes of ocular opacity and leukocoria, in addition to allowing complete evaluation of the intraocular structures and being considered an essential exam to confirm the diagnosis of PHPV.

Pseudopterígio em coelho - tratamento com tracolimus / Pseudopterygium in a rabbit - treatment with tracolimus

Background: Pseudopterygium, also known as aberrant conjunctival growth, is poorly described in the literature, althoughit is known that this abnormality is uncommon and affects dwarf rabbits and their crossbreeds. The etiology of this diseaseis unknown, but there are hypotheses that the conjunctival growth cause may have its origins in immunological factors,inflammation, traumatic conditions, or cartilage dysplasias. Thus, this study reports the treatment efficacy applied in arabbit, through the continuous use of tracolimus eye drops, after surgical procedure of conjunctival fold resection, as away of controlling the pseudopterygium in rabbits.Case: This case report discusses the positive results from the surgical and therapeutic conduct of a clinical case attended bythe Ophthalmology and Microsurgical Veterinary Service at the Hospital Veterinário Universitário (HVU) of the UFSM. Thepatient was a male rabbit, sterilized, approximately 2-year-old, crossed with a dwarf rabbit. The owner’s main complaintwas the change in the aspect of the left eye, with progressive worsening in the previous four weeks. In the ophthalmologicalexamination, the animal did not present impaired vision or discomfort, however, a vascularized pink membrane was noted,which consisted of a fold of the bulbar conjunctiva, that grew centripetally and covered 90% of the cornea in 360 degrees.The diagnosis was confirmed through visual inspection and the patient’s history. The eye alteration had a characteristicaspect, described as proliferation of the bulbar conjunctiva over the cornea, in a centripetal manner and without signs ofinflammation. In addition, other ophthalmological alterations were ruled out during the patient’s physical and specificexamination. The patient was referred for anesthetic evaluation and, in addition, pre-surgical blood tests were performed,which were normal, according to the expected ranges for the species...

Pseudopterígio em coelho - tratamento com tracolimus / Pseudopterygium in a rabbit - treatment with tracolimus

Background: Pseudopterygium, also known as aberrant conjunctival growth, is poorly described in the literature, althoughit is known that this abnormality is uncommon and affects dwarf rabbits and their crossbreeds. The etiology of this diseaseis unknown, but there are hypotheses that the conjunctival growth cause may have its origins in immunological factors,inflammation, traumatic conditions, or cartilage dysplasias. Thus, this study reports the treatment efficacy applied in arabbit, through the continuous use of tracolimus eye drops, after surgical procedure of conjunctival fold resection, as away of controlling the pseudopterygium in rabbits.Case: This case report discusses the positive results from the surgical and therapeutic conduct of a clinical case attended bythe Ophthalmology and Microsurgical Veterinary Service at the Hospital Veterinário Universitário (HVU) of the UFSM. Thepatient was a male rabbit, sterilized, approximately 2-year-old, crossed with a dwarf rabbit. The owners main complaintwas the change in the aspect of the left eye, with progressive worsening in the previous four weeks. In the ophthalmologicalexamination, the animal did not present impaired vision or discomfort, however, a vascularized pink membrane was noted,which consisted of a fold of the bulbar conjunctiva, that grew centripetally and covered 90% of the cornea in 360 degrees.The diagnosis was confirmed through visual inspection and the patients history. The eye alteration had a characteristicaspect, described as proliferation of the bulbar conjunctiva over the cornea, in a centripetal manner and without signs ofinflammation. In addition, other ophthalmological alterations were ruled out during the patients physical and specificexamination. The patient was referred for anesthetic evaluation and, in addition, pre-surgical blood tests were performed,which were normal, according to the expected ranges for the species...(AU)

Fluconazol intra-estromal - eficácia na cirurgia de abscesso estromal em equino / Intrastromal fluconazole - effectiveness in the surgery of stromal abscess in a horse

Background: Due to its ocular microflora, the equine species is predisposed to develop mycotic ulcers which, when notproperly treated, can lead to the formation of a stromal abscess. A stromal abscess occurs through the introduction ofmicroorganisms into the corneal stroma. During re-epithelialization, the foreign body is encapsulated, thus creating abarrier that protects bacteria or fungi from treatment with antimicrobial medication. This framework can end up resultingin blindness due to chronic iridocyclitis, putting the animal’s vision at risk. The current work aims to report a case of corrective surgery for stromal abscess in a mare with the administration of intraoperative intrastromal fluconazole, in orderto corroborate the effectiveness of the technique.Case: A 9-year-old mare was evaluated, with the complaint that her right eye was closed and “yellowish” and that she hadalready been treated with intramuscular injectable anti-inflammatory drugs based on flunexin meglumine (Banamine® -50 mg) for 15 days, referring to a possible ulcer in the right eye. Ophthalmic screening resulted in a negative direct reflexand no threat response in the right eye. Examination of the conjunctiva showed congestion and chemosis. Examination ofthe cornea of the right eye was negative for Fluorescein and Green Lissamine tests, and opacity and corneal neovascularization were noted. The final diagnosis was a corneal abscess of probable fungal origin secondary to a keratomycosis. Afterthe consultation, complementary blood and biochemical tests were performed, which showed normal results for the speciesin question, and treatment was started with eye drops based on atropine 1% (Fagra® - 20 mL), ciprofloxacin antimicrobialeye drops (Ciprovet Colirio® - 5 mL), and antifungal eye drops based on ketoconazole...

Cirurgia corretiva para coloboma palpebral em um felino através da técnica de transposição da comissura labial / Corrective surgery for palpebral coloboma in a feline using the technique of transposition of the lip commissure

Background: Eyelid coloboma is considered a disease caused by failure in eye development during the first semester of pregnancy. In felines, its prevalence occurs in the upper eyelids, temporal region, and bilaterally. Coloboma, whether to a large or small extent, can lead to keratoconjunctivitis sicca and trichiasis, situations that can give rise to secondary ulcerative keratitis. The only corrective method is blepharoplasty. The current work aims to report the case of corrective surgery for eyelid coloboma in a feline with a successful postoperative period, in order to corroborate the effectiveness of the technique. We also report a finding of persistent pupillary membrane. Case: A 7-month-old male feline, no defined breed, was analyzed with a purulent mucus secretion and signs of discomfort in the right eye. After the ophthalmic screening, the presence of a coloboma was identified, which occupied approximately 50% of the size of the upper eyelid, in the temporal-dorsal region of the right eye. The cat had already undergone an enucleation of the left eye due to a perforation arising from ulcerative keratitis. Together with coloboma, the presence of blepharospasm, trichiasis, keratoconjunctivitis sicca, and secondary ulcerative keratitis were diagnosed. The presence of persistent pupillary membrane was also observed, a rare condition in the feline species. To confirm the ulcer, the fluorescein test was applied and treatment with antibiotic eye drops and lacrimomimetics (tear film replacements) drops was administered until the day of surgery, one week later. Concomitant with the institution of treatment prior to surgery, blood was collected for complementary pre-surgical tests such as blood count and biochemistry, which demonstrated satisfactory results. Corrective surgery was then instituted by the technique of transposing the labial commissure...