Application of local anaesthesia and cryosurgery for eyelid masses in dogs.

BACKGROUND: Eyelid mass removal and cryotherapy application using only local anaesthesia and restraint may benefit patients with high anaesthesia risks. OBJECTIVE: To evaluate and validate cryosurgery application using the CryoPen XL® on palpebral masses under local anaesthesia for patients not suitable for general anaesthesia. METHODS: Thirty patients underwent the procedure between November 2015 and April 2020. The procedure steps were as follows: skin preparation and local anaesthesia of the affected eyelid; debulking by resection and/or squeezing out the inspissated material; cryosurgery and post-operative care using topical medication, antibiotics and anti-inflammatory ointment. The medical records of the patients who underwent the operation were evaluated. Moreover, a telephonic survey with the pet owners was performed to determine recurrence, time to recurrence, survivability and side effects. RESULTS: Among the 30 owners, 29 responded to the survey. Ten (10/38, 26.3%) masses recurred with an average time to recurrence of 6.0 months. The estimated average depths for all, non-recurred, and recurred masses were 1.89, 1.88 and 1.90 mm, respectively. The average recurrence rate and time to recurrence were higher and earlier, respectively, than previously reported values. However, no patient presented intra- or post-operative complications. CONCLUSION: These findings suggest that local anaesthesia and cryosurgery using the CryoPen XL® can be used in patients with eyelid masses who are not suitable for general anaesthesia. Compared with the surgical eyelid mass removal and blepharoplasty procedure, the reported procedure is time- and cost-effective, with the additional benefit of not requiring general anaesthesia.

LIQUID NITROGEN CRYOSURGERY FOR CUTANEOUS AND OCULAR NEOPLASMS IN KOI (CYPRINUS CARPIO) AND GOLDFISH (CARASSIUS AURATUS): EIGHT CASES (2018-2019).

Cryosurgery, also known as cryotherapy and cryoablation, is a promising surgical technique that employs highly localized freezing to destroy damaged and diseased tissue, including benign and malignant neoplasms. This procedure has been reported in the treatment of chromatophoromas, fibromas, and peripheral nerve sheath tumors in piscine patients. This study presents eight clinical cases of cryosurgery on cyprinid pet fish for a wide array of neoplastic masses, including chromatophoromas, squamous cell carcinoma, and sarcomas that were diagnosed by histopathology. Surgical excision of external masses, liquid nitrogen cryotherapy, injectable medications (meloxicam and danofloxacin), and topical medical-grade honey were applied to the patients after biopsy sampling. Five out of seven cutaneous cases and two out of three ocular cases had complete resolution without recurrence for at least three months posttreatment. Treatment was unsuccessful for two of the cutaneous cases in which the cutaneous masses were extremely invasive, resulting in severe ulceration and deep invasion into the coelomic cavity. One of the ocular cases involved a corneal mass that did not change in size and had no complications after treatments, suggesting that the treatment might be useful in limiting growth. The effectiveness of cryotherapy appears to correlate with the tumor type, as well as the stage and progression of tumor invasion.

Células-tronco mesenquimais de origem adiposa na fase de proliferação do processo de cicatrização de queimaduras frias / Adipose-derived stem cells in the proliferation phase of the healing process in cold burns

A criocirurgia tem sido utilizada no tratamento de diferentes enfermidades de sistemas e órgãos. Contudo, são relatados efeitos adversos, como cicatrização lenta, cicatrizes extensas, disfunção estética e funcional. As lesões que ocorrem naturalmente pela exposição ao frio extremo, comumente, resultam em gangrena. O presente trabalho teve como objetivo avaliar a influência das células-tronco mesenquimais de origem adiposa (ADSCs) na fase de proliferação da cicatrização de feridas cutâneas. Por meio da aplicação do nitrogênio líquido pela técnica do spray aberto, realizou-se a indução de uma ferida, de aproximadamente 15mm de diâmetro, na região dorsal de cada rato. A ferida recebeu o tratamento de acordo com o grupo ao qual pertencia: 1) aplicação das ADSCs no 15º dia (grupo tratado); 2) aplicação da solução cloreto de sódio 0,9% no 15º dia (grupo sham); 3) nenhuma intervenção até o momento da eutanásia (grupo controle). O grupo tratado com as ADSCs apresentou as maiores taxas de contração média das feridas e obteve diferença estatisticamente significativa em relação ao grupo sham quanto à neovascularização. A terapia com as ADSCs proporcionou uma relevante evolução clínica das feridas, podendo ser constatada ao final do período de avaliação por cicatrizes mais estreitas e compridas.(AU)

Cryosurgery has been used to treat different diseases of systems and organs, although adverse effects have been reported such as delayed wound healing, large scars, esthetical deformation and functional impairment. Injuries caused naturally by the exposure to extreme cold weather conditions mostly result in gangrene. This study aims to evaluate the influence of adipose-derived stem cells (ADSCs) in the proliferation phase on cutaneous wound healing. Through the application of liquid nitrogen by the spraying technique, a 15 millimeter diameter lesion was produced in the dorsal region of each rat. The wound received treatment according to the group it belonged: 1) ADSCs application on the 15th day (treated group); 2) application of 0.9% sodium chloride solution on the 15th day (sham group); 3) no intervention until euthanasia (control group). The group treated with ADSCs showed the highest wound average contraction rate; this group got a significant statistical difference in relation to the sham group when it refers to neovascularization. The ADSCs therapy provides an important clinical evolution of wounds. This was verified at the end of the evaluation period through narrower and longer scars.(AU)

Short communication: Evaluation of the efficacy of novel disbudding methods for dairy calves.

The objectives of this study were to (1) evaluate whether cryoablation or the administration of clove oil was as efficacious as cautery disbudding at preventing horn growth, and (2) evaluate whether the efficacy of cautery disbudding is affected by removing or leaving the horn bud tissue intact after disbudding of dairy calves. At approximately 4 d of age (4.0 ± 0.88 d of age, mean ± SD), 265 dairy heifer calves from 3 dairy farms (farm 1: n = 129 calves; farm 2: n = 109 calves; farm 3: n = 27 calves) were disbudded. Each calf had 1 of 4 treatments randomly assigned to each horn bud: (1) clove oil (0.5 mL) administered subcutaneously under the horn bud (CLOV, n = 135 buds); (2) a liquid nitrogen-filled probe applied to the horn bud area for 30 s (CRYO, n = 134 buds); (3) cautery disbudding using an electric hot-iron and the horn bud removed (BUDOFF, n = 130); or (4) cautery disbudding and the horn bud tissue left intact (BUDON, n = 131). Calves were assessed for signs of infection at the disbudding site frequently within the first month after disbudding. At approximately 6 mo of age (6 ± 2.2 mo, mean ± SD) calves were assessed for scur or horn growth. The disbudding procedures were considered successful if no scur or horn development was observed. Within the first month, 12% of disbudding wounds showed some indication of infection, such as pus, exudate, or swelling; of the infected buds, 52% were associated with the BUDON treatment, 27% with CLOV, 25% with BUDOFF, and 2% with CRYO treatments. At 6 mo of age, BUDOFF was the most effective method of preventing horn growth and CRYO was the least efficacious [mean percentage of success: BUDOFF: 100% (95% CI: 97.7-100.0); CRYO: 1% (95% CI: 0.2-5.3)]. Injecting clove oil under the horn bud was 87% (95% CI: 80.6-92.5) successful. Not removing the horn bud tissue after cautery disbudding reduced the efficacy of this method by 9% [91% success (95% CI: 83.8-95.7)]; moreover, this method was associated with more infection at the site of disbudding. It appears as though the clove oil treatment could be used as an alternative to cautery disbudding of dairy calves; however, further research is needed to evaluate the tissue damage and associated pain caused by clove oil and to refine this technique (i.e., administration methods to improve efficacy) before it could be considered an alternative to cautery.

Pain sensitivity and injury associated with three methods of disbudding goat kids: Cautery, cryosurgical and caustic paste.

Pain sensitivity and skull/brain injury associated with cautery, cryosurgical and caustic paste disbudding were evaluated in goat kids. Kids (reared for meat; n=280) were randomly assigned to one of four treatments (n=70 per treatment): (1) sham-handling (SHAM) or (2) cautery (CAUT), (3) cryosurgical (CRYO) or (4) caustic paste (CASP) disbudding. A pain sensitivity test was carried out 15min pre-treatment and 1h post-treatment. Skull/brain injury was assessed at post-mortem examination. Kids with evidence of injury to the skull/brain, as well as a random sample of kids (n=15 per treatment) without evidence of skull/brain injury, were selected for histological examination of brain tissue. Average daily gains (ADG) were calculated from body weight measurements taken 10min pre-treatment and then at 2, 7 and 14days post-treatment as a measure of the potential effects of pain or injury on growth. CASP and CRYO kids displayed higher pain sensitivity post-treatment than CAUT or SHAM kids, suggesting that they experienced more acute pain 1h post-treatment. One of 70 CAUT kids had a perforated skull, but there was no histological evidence of brain injury in this animal; a further nine CAUT kids exhibited hyperaemia of the skull. The other treatments did not result in injury to the skull/brain. There was no evidence of a difference in ADG across treatments. Caustic paste and cryosurgical disbudding resulted in greater acute pain sensitivity than cautery disbudding; however, cautery disbudding has the potential to cause skull injury if performed incorrectly.

Combined carbon dioxide laser and cryosurgical ablation of rostral nasal septum squamous cell carcinoma in 10 dogs.

BACKGROUND: Squamous cell carcinoma (SCC) is the most commonly reported neoplasm of the nasal planum and treatment is focused on localized disease. Rostral maxillectomy and/or nasal planectomy are considered standard of care for excision of nasal planum SCC; however, the cosmetic outcome of these procedures can be deemed unacceptable by many pet owners. OBJECTIVES: The study aim was to evaluate the efficacy of combination carbon dioxide (CO2 ) laser surgery and cryosurgery as a palliative treatment modality in dogs with nasal SCCs. ANIMALS: Ten client-owned dogs with nasal SCC were included: seven neutered males, two spayed females and one intact male, with a median age of 12.5 years (range 9-15 years). METHODS AND MATERIALS: Tumour CO2 laser ablation was followed by cryosurgical ablation of the visible tumour, adjacent and subjacent tissue. Three rapid freeze-slow thaw cycles were performed. RESULTS: Eight of 10 dogs were Labrador retrievers. The ages ranged from 9 to 14 years. Overall median survival time was 260 days with two dogs still alive at the time of writing. CONCLUSIONS AND CLINICAL IMPORTANCE: Combined CO2 laser and cryosurgical ablation was practical, cost-effective and provided an excellent aesthetic outcome in dogs with SCCs restricted to the nasal septum, while providing acceptable palliation of local disease.

A novel in vivo porcine model of intervertebral disc degeneration induced by cryoinjury.

PURPOSE: Degenerative disc disease involves sequential events that lead to the loss of cells, a decrease in disc matrix production, disc dehydration, and alteration of its biomechanical properties. The aim of this study was to determine whether cryoinjury of the nucleus pulposus performed through endplate perforation contributes to disc degeneration and to compare this technique with standard methods. METHOD: Under general anesthesia, the lumbar discs of six pigs were exposed and randomly submitted to needle puncture of the annulus fibrosus (NeP), isolated endplate injury (EP), or cryoinjury using a 2.5-J Thompson cryoprobe applied through a single endplate perforation (EP+cryo). The remaining discs served as controls. Animals were sacrificed at two months and the harvested lumbar spines were submitted to CT scan and MRI investigations. Histologic analysis was performed to assess the degree of disc degeneration. RESULTS: CT scan showed that decrease in average disc height was more important after cryoinjury (49.3%) than after endplate perforation (16.9%) (P < 0.0001) or needle puncture (19.4%) (P < 0.0001). On MRI, the dehydration ratio was significantly more important after EP+cryo (60%) than after NP (40%) or EP (30%) (P < 0.0001). After cryoinjury, the histologic score developed for this study was significantly higher than after needle puncture or endplate perforation (P < 0.0001). CONCLUSIONS: Imaging and histological analysis showed that disc cryoinjury applied through endplate perforation was superior to the classical NeP and EP models to induce experimental disc degeneration. This model appears suitable for testing safety and efficacy of novel treatments of intervertebral disc degeneration.

Evaluation of the cryosurgery for treatment of squamous cell carcinoma in cats / Avaliação da criocirurgia no tratamento do carcinoma de células escamosas em gatos

The cryosurgery is a very useful therapy for the treatment of a variety of neoplastic and non-neoplastic processes. Nevertheless, it is still poorly described as an option for the treatment of specific cutaneous neoplasms, such as squamous cell carcinoma. The purpose of the present study was to analyze the clinical response of cryosurgery for the treatment of squamous cell carcinoma in cats. For this 13 squamous cell carcinoma lesions were selected in 11 cats, diagnosed through citopathological and/or histopathological examinations. The lesions were frozen using liquid nitrogen spray, and the evaluations were performed in the moment of freeze and approximately every 15 days until the wound was completely healed. The response of cryosurgery was considered complete with tumoral remission on 38.5% of the cats, and partial on 46.1%. The main complications included crusting and nostril stenosis. The presented results suggested that cryosurgery is effective and may be a viable option for the treatment of squamous cell carcinoma in cats. The effectiveness of the therapy; however, depends on the correct selection of the candidates for cryosurgery based on the lesion size, and the attendance to some criteria, such as the freezing time and post-operative care.(AU)

A criocirurgia tem se mostrado uma terapia de grande auxílio no tratamento de uma variedade de processos neoplásicos e não neoplásicos. Apesar disso, ainda é pouco descrita a utilização da criocirurgia como opção de tratamento de neoplasias cutâneas específicas, como o carcinoma de células escamosas. Objetivou-se com o presente estudo analisar a resposta clínica da criocirurgia para o tratamento do carcinoma de células escamosas em gatos. Para isso, foram selecionadas 13 lesões do tipo carcinoma de células escamosas em 11 gatos, diagnosticadas por meio de análise citopatológica e/ou histopatológica. As lesões foram congeladas por meio de nitrogênio líquido na forma de spray, e as avaliações realizadas no momento do congelamento e aproximadamente a cada 15 dias, até a completa cicatrização da ferida. A resposta da criocirurgia foi considerada completa, com remissão tumoral em 38,5% dos gatos e parcial em 46,1% destes. As principais complicações verificadas incluíram a formação de crostas e estenose de narina. Os resultados apresentados no presente estudo sugerem que a criocirurgia é efetiva e pode ser uma opção viável para o tratamento do carcinoma de células escamosas em gatos. O sucesso do tratamento, entretanto, depende da correta seleção dos candidatos à técnica quanto ao tamanho da lesão, e do atendimento a alguns critérios, como o tempo de congelamento e os cuidados pós-operatórios.(AU)

Persistent papilloma treated with cryotherapy in three dogs.

BACKGROUND: Canine papillomaviruses can affect the mucous membranes and skin of young, old and immunocompromised dogs. Most lesions regress spontaneously over a four to eight week interval; however, in some cases the lesions may persist or progress. Cryotherapy is used as a treatment for papillomavirus induced lesions in veterinary practice but there is limited published evidence regarding its use. OBJECTIVES: To describe the history, lesions and treatment outcomes of three dogs with persistent viral papillomas treated with cryotherapy. ANIMALS: Three client owned dogs. METHODS: Canine viral papilloma lesions were treated with five to six freeze-thaw cycles using liquid nitrogen cryotherapy. RESULTS: All lesions in each case resolved with cryotherapy treatment. Two cases required one treatment and one case required two treatment courses. CONCLUSIONS AND CLINICAL IMPORTANCE: The apparent resolution of these papilloma lesions with cryotherapy suggests that this may be a useful treatment intervention for persistent canine papilloma lesions. Spontaneous resolution may still have taken place; consequently, large scale clinical trials are required to demonstrate unequivocally that this mode of therapy, as with other therapeutic modalities, is really effective in the treatment of canine papillomatosis.

Characterization of Normal and Freeze-Thawed Tissues in vitro Through The Ultrasonic Integrated Backscatter.

BACKGROUND: The ultrasound guidance of cryotherapy could be improved if changes of tissue characterization parameters during freezing could be used to monitor freezing patterns and estimate the postoperative effects after surgery. OBJECTIVE: The ultrasonic integrated backscatter analysis holds promise as an effective method for signal analysis and characterization of thawed tissues. MATERIALS AND METHODS: The ultrasonic integrated backscatter has been found to be an important parameter for describing the ultrasonic scattering and characterization of biological tissues. However, its potential values in the evaluation of cryosurgical effects of tissues reserved unclear so far. Here, we investigated the power spectrum of acoustic signal to estimate the ultrasound integrated backscatter in normal and freeze-thawed tissues on porcine livers in vitro. RESULTS: The experimental results carried out at 10 MHz using weakly focused pulse-echo signal element transducer indicated that the ultrasonic integrated backscatter in normal liver tissues is 31.3±4.6 whereas it is 44.2±6.5 in several pre-frozen and then thawed tissues. CONCLUSION: These results disclosed the good correlation between the ultrasonic integrated backscatter and microstructures of the normal or thawed tissues, and hence demonstrated that the power spectrum holds promise to be used as an effective method for the characterization of thawed tissues ultrasonic integrated backscatter, which might offer a potential pragmatic prospect for the practice of monitoring transition zone between frozen and unfrozen tissues during the surgical therapy, and evaluating postoperative effects.

Cryosurgery in association with itraconazole for the treatment of feline sporotrichosis.

OBJECTIVES: We evaluated the efficacy of cryosurgery in association with itraconazole for the treatment of feline sporotrichosis. We also compared the length of treatment protocol with others reported in the literature. METHODS: Cats naturally infected with fungi of the Sporothrix schenckii complex were evaluated. Diagnosis was confirmed by cytology and fungal culture. Prior to the cryosurgical procedure, every animal was receiving itraconazole 10 mg/kg/day PO, for different time periods. The same protocol was maintained until 4 weeks after complete healing of the lesions. RESULTS: Eleven of 13 cats were considered clinically cured. The treatment duration ranged from 14-64 weeks (median 32 weeks). CONCLUSIONS AND RELEVANCE: The combination of cryosurgery and itraconazole was effective in treating cases of feline sporotrichosis and decreased the treatment length compared with protocols using only medication.

Local photodynamic therapy delays recurrence of equine periocular squamous cell carcinoma compared to cryotherapy.

OBJECTIVE: (i) To report the successful treatment of 10 cases of equine periocular squamous cell carcinoma (PSCC) with surgical excision and photodynamic therapy (PDT) using verteporfin. (ii) To evaluate time to first tumor recurrence between PDT-treated horses and horses treated with surgical excision and cryotherapy. METHODS: A total of 24 equine PSCC cases were included: group 1 (n = 14) had excision and cryotherapy (1993­2003), group 2 (n = 10), excision and local PDT (2006­2010). Evaluated data: signalment, treatment method, tumor location, size, and time to first recurrence. Groups were compared via chi-square test for categorical variables and Wilcoxon rank-sum test for numeric variables. Time to tumor recurrence was examined using Kaplan­Meier product-limit survival analysis. RESULTS: Of 24 cases, nine breeds were affected. Mean age at treatment in years: 14 (range 5­24) in group 1; 11 (range 8­18) in group 2. Median tumor size: 163 mm2 (range 20­625 mm2) in group 1; 195 mm2 (range 45­775 mm2) in group 2. Signalment, tumor laterality, and size were not significantly different between groups. Time to recurrence was significantly different between groups (Logrank test, P = 0.0006). In group 1, 11/14 horses had tumor regrowth with median time to recurrence in months: 10 (range 1­44). In group 2 (minimum follow-up of 25 months; range 25­50), no horse demonstrated tumor recurrence after one treatment with excision and PDT. CONCLUSIONS: This represents the first report of local PDT using verteporfin for treatment of equine PSCC. Following surgery, the likelihood of tumor recurrence was significantly reduced with local PDT compared with cryotherapy.

Image-guided transnasal cryoablation of a recurrent nasal adenocarcinoma in a dog.

An eight-year-old female spayed Airedale terrier with rapid recurrence of a nasal adenocarcinoma following image-guided intensity-modulated radiation therapy was treated with transnasal, image-guided cryotherapy. Ice ball size and location were monitored real-time with computed tomography-fluoroscopy to verify that the entire tumour was enveloped in ice. Serial computed tomography scans demonstrated reduction in and subsequent resolution of the primary tumour volume corresponding visually with the ice ball imaged during the ablation procedure. Re-imaging demonstrated focallysis of the cribriform plate following ablation that spontaneously resolved by 13 months. While mild chronic nasal discharge developed following cryoablation, no other clinical signs of local nasal neoplasia were present. Twenty-one months after nasal tumour cryoablation the dog was euthanased as a result of acute haemoabdomen. Image-guided cryotherapy may warrant further investigation for the management of focal residual or recurrent tumours in dogs, especially in regions where critical structures preclude surgical intervention.

Multiple eyelid apocrine hidrocystoma in a domestic short-haired cat.

A 12-year-old domestic short-haired cat was referred for evaluation of periocular masses. The tail had similar masses and was amputated previously by the referring veterinarian. On examination, multiple pigmented nodules, 3-15 mm in diameter, were found in the periocular skin, primarily involving the palpebral eyelid margin. A wedge excisional biopsy revealed small cuboidal cells forming multiple tubular and cystic structures indicative of apocrine cystadenomas, similar to apocrine hidrocystomas described in humans. The nodules were lanced followed by liquid nitrogen cryofreezing.

Clinical study of cryosurgery efficacy in the treatment of skin and subcutaneous tumors in dogs and cats.

OBJECTIVE: To evaluate the efficacy of cryosurgery for treatment of skin and subcutaneous tumors in dogs and cats. STUDY DESIGN: Prospective study. ANIMALS: Dogs (n=20), cats (10). METHODS: Cutaneous or subcutaneous tumors were treated by liquid nitrogen cryosurgical spray (1 cm from target tissue at 90 degrees until a 5-mm halo of frozen tissue was achieved) for 15-60 seconds. Malignant lesions had 3 freeze-thaw cycles benign tumors, 2 cycles. The second or third freeze cycle was performed after complete thaw of the preceding freeze. Wounds healed by second intention. Follow-up was weekly for 1 month and then twice monthly until wounds healed, and final outcome was determined by telephone interview of owners. RESULTS: Tumor size ranged from 0.3 to 11 cm diameter with 28 (60%) being 0.3-1 cm; 8 (17%) 1.1-3 cm, and 11 (23%) >3.4 cm. Complications included edema, erythema and for extremity lesions, pain and lameness. Treated lesions (n=47) had an overall remission of 98% (mean follow-up, 345+/-172.02 days [range, 150-750 days]). One malignant peripheral nerve sheath tumor recurred 7 months after cryosurgical treatment. CONCLUSION: Cryosurgery is an efficient method for treatment of skin and subcutaneous tumors in dogs and cats. CLINICAL RELEVANCE: Cryosurgical ablation is an effective means of treating small cutaneous or subcutaneous tumors in dogs and cats, especially in older animals where wound closure or cosmetic outcome might limit surgical excision alone.

Cryohypophysectomy used in the treatment of a case of feline acromegaly.

A 10-year-old female spayed cat was diagnosed with acromegaly secondary to a pituitary tumour. At the time of diagnosis, the cat had insulin-resistant diabetes mellitus and its insulin-like growth factor-I levels were elevated. Clinical signs included polyuria, polydipsia and weight gain. Persistent hyperglycaemia and glucosuria were identified, and fructosamine levels remained elevated. Magnetic resonance imaging of the brain showed a pituitary tumour. Transsphenoidal cryohypophysectomy was used to treat the pituitary tumour. Postoperatively, the serum insulin-like growth factor-I levels decreased and the diabetes mellitus was controlled with routine levels of insulin. To the authors' knowledge, this is the second reported case of acromegaly treated with cryohypophysectomy, and the first that reports a favourable long-term outcome. Cryohypophysectomy may be a safe and effective treatment for cats with a pituitary mass resulting in acromegaly.

Squamous cell carcinoma of the nasal planum in cats and dogs.

The purpose of this article is to review the therapeutic options available for the treatment of squamous cell carcinoma of the nasal planum in cats and dogs. The techniques of complete and partial nasal planum resection in the cat are described in detail. Surgical treatment offers the greatest chance of cure, although several options are available for early, less invasive lesions.

Superficial keratectomy and cryosurgery as therapy for limbal neoplasms in 13 horses.

OBJECTIVE: To determine the usefulness and clinical outcome of a combined procedure of superficial keratectomy and cryosurgery as a treatment for limbal neoplasms in horses. STUDY DESIGN: Retrospective study. ANIMALS: Thirteen horses with 14 limbal tumors. METHODS: Medical records of all patients with limbal tumors, referred to the Department of Equine Sciences of Utrecht University between 1995 and 2002, were retrieved. Patient data were analyzed with respect to signalment, tumor surface area and histologic diagnosis. Surgery, performed under general anesthesia, included surgical debulking of the tumor followed by cryosurgery. Long-term follow-up information was obtained by re-evaluation in the clinic, by the referring veterinarian, and/or by telephone enquiry. RESULTS: Therapy was successful in 9 out of 14 eyes after the first attempt (64%); one eye needed retreatment (7%), and four eyes were eventually enucleated (29%). The mean follow-up period was 4.8 years. The initial surface area of the tumor significantly influenced outcome (P < 0.01). Squamous cell carcinoma was the most predominant tumor type (79%). Haflinger horses accounted for 69% of the cases whereas their occurrence in the overall hospital population is approximately 5%. CONCLUSIONS AND CLINICAL RELEVANCE: The described technique of superficial keratectomy and cryosurgery is a simple procedure for the treatment of limbal tumors in equine patients that does not require sophisticated equipment. Nor is it tampered by legal restriction, and appears to be effective in tumors with a small surface area (< 2 cm2). Haflinger horses seem to be predisposed for the development of ocular squamous cell carcinoma.

Sarcoids in captive zebras (Equus burchellii): association with bovine papillomavirus type 1 infection.

Sarcoids were diagnosed in two captive zebras from different facilities. Zebra 1 (Equus burchellii boehmi) was a 4.5-yr-old, captive-born male that presented with a 9- by 7-cm inguinal mass. Seven months after surgical excision of the inguinal mass, the zebra presented with a similar lesion in the right upper eyelid that has relapsed repeatedly and has not responded to treatment including local cisplatin injections and cryosurgery. Zebra 2 (of undetermined taxon) was housed at a private wild animal farm. The zebra presented with a single, raised, 2.5- by 2.0- by 2.0-cm, ulcerated mass on the nose, and surgical excision was curative. Histologically, the three masses consisted of a dermal, compact, nonencapsulated, poorly demarcated neoplasm composed of well-differentiated spindle cells arranged in streams and whorls and accompanied by moderate epidermal hyperplasia with long rete pegs. On the basis of the morphologic resemblance to the unique equine cutaneous neoplasm, "sarcoid" was diagnosed. This is the first description of sarcoids in captive zebras. Association with bovine papillomavirus (BPV) type 1, as it occurs in horses, was demonstrated by polymerase chain reaction, nucleic acid sequencing, and in situ hybridization (ISH) on paraffin-embedded tissues from the inguinal mass of zebra 1. Sequencing revealed 98% identity of the 244-bp fragment with BPV type 1. The ISH for BPV type 1 DNA intensely stained the nuclei of neoplastic mesenchymal spindle cells. The sites and the clinical behavior of the sarcoids in these zebras are similar to those described in horses.

Comparison of systemic responses of radiofrequency ablation, cryotherapy, and surgical resection in a porcine liver model.

BACKGROUND: The degree of systemic response after hepatic radiofrequency ablation (RFA) has not been well investigated. METHODS: An in vivo study was conducted on 23 domestic swine. Different hepatic procedures (RFA, cryotherapy, hepatic pedicle ligation, and hepatectomy) were performed on the medial lobe of the liver (30% of the liver volume). Systemic responses in terms of systemic inflammatory marker changes and end-organ functions were determined. RESULTS: During the early postoperative period, the systemic inflammatory marker concentrations (tumor necrosis factor-alpha and interleukin-1beta) in the RFA group were significantly lower than in the cryotherapy group but significantly higher than in the control group. The corresponding concentrations in the hepatectomy group remained similar to those in the control group. The pattern of changes of serum inflammatory marker concentrations in the pedicle ligation group followed the pattern in the RFA group. The serum intracellular content concentrations (lactate dehydrogenase and urate) of the cryotherapy group peaked at 6 hours after operation, which was significantly later than in the other groups. Liver function, renal function, and coagulation profiles remained normal in the RFA group. However, the renal function deteriorated in the cryotherapy group on day 1. Both platelet count and activated clotting time showed significant derangement in the cryotherapy group compared with the control group. There was more severe interstitial pneumonitic change of the porcine lung after cryotherapy than after RFA. CONCLUSIONS: The systemic responses of RFA were significantly less severe than those of cryotherapy in this porcine model. However, the increase in serum inflammatory markers and pneumonitis after RFA was substantial when compared with hepatectomy.