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- Author or Editor: Michelle L. Oblak x
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Abstract
OBJECTIVE
To compare the effect of volume and solution on transit time and fluorescence intensity (FI) using near-infrared fluorescence imaging (NIRF) in a simulated tumor model in cats. Secondarily, to describe SLN mapping with indocyanine green (ICG) NIRF and report any adverse effects of intradermally injected ICG in cats.
ANIMALS
7 healthy purpose-bred domestic shorthaired male cats.
METHODS
Cats were randomly divided into 2 groups (ICG or ICG + methylene blue [MB]). Transit time and FI were determined for 1 or 2 mL solutions injected intradermally in 4 quadrants around a simulated tumor. Following massage, fluorescence intensity was quantified by calculating the corrected total ROI fluorescence using ImageJ software. Cats were monitored for adverse effects up to 4 weeks post-injection.
RESULTS
A larger solution volume had decreased transit times to the SLN (P = .001). There was no significant difference in transit times between ICG and ICG-MB. ICG demonstrated a greater FI (P = .001) in the SLN compared to ICG-MB. Methylene blue did not percutaneously fluoresce under NIRF. The volume of the solution did not significantly affect FI. No adverse reactions were reported.
CLINICAL RELEVANCE
Increased volume of ICG may aid in rapid percutaneous lymphatic tracking from tumor to SLN. Indocyanine green alone may be preferred over ICG-MB for greater visualization of the SLN. Intradermal injections of ICG and ICG-MB were well-tolerated in healthy cats with no significant complications. Clinical evaluation of this technique in an impaired lymphatic system, as seen in cancer patients, should be assessed in future research.
Abstract
OBJECTIVE
To conduct a retrospective multi-institutional study reporting short- and long-term outcomes of adrenalectomy in patients presenting with acute hemorrhage secondary to spontaneous adrenal rupture.
ANIMALS
59 dogs and 3 cats.
METHODS
Medical records of dogs and cats undergoing adrenalectomy between 2000 and 2021 for ruptured adrenal masses were reviewed. Data collected included clinical presentation, preoperative diagnostics, surgical report, anesthesia and hospitalization findings, histopathology, adjuvant treatments, and long-term outcome (recurrence, metastasis, and survival).
RESULTS
Median time from hospital admission to surgery was 3 days, with 34% of surgeries being performed emergently (within 1 day of presentation). Need for intraoperative blood transfusion was significantly associated with emergent surgery and presence of active intraoperative hemorrhage. The short-term (≤ 14 days) complication and mortality rates were 42% and 21%, respectively. Negative prognostic factors for short-term survival included emergent surgery, intraoperative hypotension, and performing additional surgical procedures. Diagnoses included adrenocortical neoplasia (malignant [41%], benign [12%], and undetermined [5%]), pheochromocytoma (38%), a single case of adrenal fibrosis and hemorrhage (2%), and a single case of hemangiosarcoma (2%). Local recurrence and metastasis of adrenocortical carcinoma were confirmed in 1 and 3 cases, respectively. Overall median survival time was 574 days and 900 days when short-term mortality was censored. No significant relationship was found between histopathological diagnosis and survival.
CLINICAL RELEVANCE
Adrenalectomy for ruptured adrenal gland masses was associated with similar short- and long-term outcomes as compared with previously reported nonruptured cases. If hemodynamic stability can be achieved, delaying surgery and limiting additional procedures appear indicated to optimize short-term survival.
Abstract
OBJECTIVE
To compare complications and outcome following unilateral, staged bilateral, and single-stage bilateral ventral bulla osteotomy (VBO) in cats.
ANIMALS
282 client-owned cats treated by VBO at 25 veterinary referral and academic hospitals from 2005 through 2016.
PROCEDURES
Medical records of cats were reviewed to collect information on signalment, clinical signs, diagnostic test results, surgical and postoperative management details, complications (anesthetic, surgical, and postoperative), and outcome. Associations were evaluated among selected variables.
RESULTS
Unilateral, staged bilateral, and single-stage bilateral VBO was performed in 211, 7, and 64 cats, respectively, representing 289 separate procedures. Eighteen (9%), 2 (29%), and 30 (47%) of these cats, respectively, had postoperative respiratory complications. Cats treated with single-stage bilateral VBO were significantly more likely to have severe respiratory complications and surgery-related death than cats treated with other VBO procedures. Overall, 68.2% (n = 197) of the 289 procedures were associated with Horner syndrome (19.4% permanently), 30.1% (87) with head tilt (22.1% permanently), 13.5% (39) with facial nerve paralysis (8.0% permanently), and 6.2% (18) with local disease recurrence. Cats with (vs without) Horner syndrome, head tilt, and facial nerve paralysis before VBO had 2.6, 3.3, and 5.6 times the odds, respectively, of having these conditions permanently.
CONCLUSIONS AND CLINICAL RELEVANCE
Findings suggested that staged bilateral VBO should be recommended over single-stage bilateral VBO for cats with bilateral middle ear disease. Cats with Horner syndrome, head tilt, and facial nerve paralysis before surgery were more likely to have these conditions permanently following surgery than were cats without these conditions.
Abstract
OBJECTIVE
To determine whether conservative lateral surgical margins (equal to tumor diameter for tumors < 2 cm in diameter or 2 cm for larger tumors) were noninferior to wide (3-cm) lateral surgical margins for achieving tumor-free histologic margins following excision of grade I and II cutaneous mast cell tumors (MCTs) in dogs.
ANIMALS
83 grade I and II MCTs excised with a deep surgical fascial margin and requisite lateral surgical margins from 68 dogs from 2007 to 2017. Tumors representing scar revision or local recurrence were excluded.
PROCEDURES
A pathology department database was searched to identify qualifying MCTs, and medical records were cross-referenced to obtain data regarding patients and tumors. Outcome (complete vs incomplete excision as histologically determined) was compared between conservative- and wide-margin groups. A noninferiority margin of ≥ 0.9 was used for the risk ratio (probability of complete excision for the conservative- vs wide-margin group), implying that noninferiority would be established if the data indicated that the true risk of complete excision with the conservative-margin approach was at worst 90% of that for the wide-margin approach.
RESULTS
The proportion of excised MCTs with tumor-free histologic margins was similar between the conservative- (43/46 [93%]) and wide- (34/37 [92%]) margin groups. There were no differences in tumor diameter or location between treatment groups. The risk ratio (1.02; 95% confidence interval, 0.89 to 1.19) met the criterion for noninferiority.
CONCLUSIONS AND CLINICAL RELEVANCE
The conservative-margin approach appeared to be noninferior to the wide-margin approach for achieving tumor-free histologic margins in the dogs of this study, and its use could potentially reduce the risk of postoperative complications. (J Am Vet Med Assoc 2020;256:567-572
Abstract
OBJECTIVE
To report the perioperative characteristics and outcomes of dogs undergoing laparoscopic-assisted splenectomy (LAS).
ANIMALS
136 client-owned dogs.
PROCEDURES
Multicentric retrospective study. Medical records of dogs undergoing LAS for treatment of naturally occurring splenic disease from January 1, 2014, to July 31, 2020, were reviewed. History, signalment, physical examination and preoperative diagnostic test results, procedural information, complications, duration of hospitalization, histopathologic diagnosis, and perioperative outcomes were recorded. Perioperative complications were defined using the Veterinary Cooperative Oncology Group – Common Terminology Criteria for Adverse Events (VCOG-CTCAE v2) guidelines.
RESULTS
LAS was performed for treatment of a splenic mass (124/136 [91%]), immune-mediated disease (7/136 [5%]), splenomegaly (4/136 [3%]), or immune-mediated disease in conjunction with a splenic mass (1/136 [1%]). Median splenic mass size was 1.3 cm3/kg body weight. Conversion to open laparotomy occurred in 5.9% (8/136) of dogs. Complications occurred in 78 dogs, with all being grade 2 or lower. Median surgical time was 47 minutes, and median postoperative hospital stay was 28 hours. All but 1 dog survived to discharge, the exception being postoperative death due to a suspected portal vein thrombus.
CLINICAL RELEVANCE
In the dogs of this report, LAS was associated with low rates of major complications, morbidity, and mortality when performed for a variety of splenic pathologies. Minimally invasive surgeons can consider the LAS technique to perform total splenectomy in dogs without hemoabdomen and with spleens with modest-sized splenic masses up to 55.2 cm3/kg, with minimal rates of complications, morbidity, and mortality.
Abstract
OBJECTIVE
To provide updated information on the distribution of histopathologic types of primary pulmonary neoplasia in dogs and evaluate the effect of postoperative adjuvant chemotherapy in dogs with pulmonary carcinoma.
ANIMALS
340 dogs.
PROCEDURES
Medical records of dogs that underwent lung lobectomy for removal of a primary pulmonary mass were reviewed, and histopathologic type of lesions was determined. The canine lung carcinoma stage classification system was used to determine clinical stage for dogs with pulmonary carcinoma.
RESULTS
Pulmonary carcinoma was the most frequently encountered tumor type (296/340 [87.1%]), followed by sarcoma (26 [7.6%]), adenoma (11 [3.2%]), and pulmonary neuroendocrine tumor (5 [1.5%]); there was also 1 plasmacytoma and 1 carcinosarcoma. Twenty (5.9%) sarcomas were classified as primary pulmonary histiocytic sarcoma. There was a significant difference in median survival time between dogs with pulmonary carcinomas (399 days), dogs with histiocytic sarcomas (300 days), and dogs with neuroendocrine tumors (498 days). When dogs with pulmonary carcinomas were grouped on the basis of clinical stage, there were no significant differences in median survival time between dogs that did and did not receive adjuvant chemotherapy.
CLINICAL RELEVANCE
Results indicated that pulmonary carcinoma is the most common cause of primary pulmonary neoplasia in dogs; however, nonepithelial tumors can occur. Survival times were significantly different between dogs with pulmonary carcinoma, histiocytic sarcoma, and neuroendocrine tumor, emphasizing the importance of recognizing the relative incidence of these various histologic diagnoses. The therapeutic effect of adjuvant chemotherapy in dogs with pulmonary carcinoma remains unclear and warrants further investigation.
Abstract
OBJECTIVE
To assess histologic evaluation of mandibular lymph nodes (MLNs) and medial retropharyngeal lymph nodes (MRLNs) for metastatic disease during tumor staging for dogs with oral malignant melanoma (OMM) and oral squamous cell carcinoma (OSCC).
DESIGN
Retrospective multi-institutional study.
ANIMALS
27 dogs with OMM and 21 dogs with OSCC.
PROCEDURES
Medical record databases of 8 institutions were searched to identify dogs with OMM or OSCC that underwent unilateral or bilateral extirpation of the MLNs and MRLNs during the same procedure between January 2004 and April 2016. Information extracted from the records included signalment, primary mass location and size, diagnostic imaging results, histologic results for the primary tumor and all lymph nodes evaluated, and whether distant metastasis developed.
RESULTS
Prevalence of lymph node metastasis did not differ significantly between dogs with OMM (10/27 [37%]) and dogs with OSCC (6/21 [29%]). Distant metastasis was identified in 11 (41%) dogs with OMM and was suspected in 1 dog with OSCC. The MRLN was affected in 13 of 16 dogs with lymph node metastasis, and 3 of those dogs had metastasis to the MRLN without concurrent metastasis to an MLN. Metastasis was identified in lymph nodes contralateral to the primary tumor in 4 of 17 dogs that underwent contralateral lymph node removal.
CONCLUSIONS AND CLINICAL RELEVANCE
Results indicated histologic evaluation of only 1 MLN was insufficient to definitively rule out lymph node metastasis in dogs with OMM or OSCC; therefore, bilateral lymphadenectomy of the MLN and MRLN lymphocentra is recommended for such dogs.
Abstract
OBJECTIVE To describe the operative technique and perioperative outcome for laparoscopic-assisted splenectomy (LAS) in dogs.
DESIGN Retrospective case series.
ANIMALS 18 client-owned dogs.
PROCEDURES Medical records of dogs with naturally occurring disease of the spleen treated by means of LAS between 2012 and 2014 were reviewed. History, signalment, results of physical examination, results of preoperative diagnostic testing, details of surgical technique, intraoperative findings including results of abdominal exploration and staging, concurrent surgical procedures, complications, histopathologic diagnoses, duration of postoperative hospitalization, and perioperative outcome were recorded. The perioperative period was defined as the time from hospital admission for LAS until discharge or death (within the same visit).
RESULTS All dogs underwent initial abdominal exploration and staging via multiple 5-mm laparoscopic ports (n = 2) or a single commercially available multichannel port (16), followed by minilaparotomy with insertion of a wound retraction device, progressive exteriorization of the spleen, sealing of hilar vessels, and splenectomy. Splenectomy was performed for treatment of a splenic mass (n = 15), suspected neoplasia (2), or refractory immune-mediated disease (1). Median size (width × length) of splenic masses was 5 × 5 cm (range, 1.6 to 11.0 cm × 1.5 to 14.5 cm). Complications were limited to minor intraoperative hemorrhage in 1 dog; no patient required conversion to open laparotomy.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that LAS was technically feasible in dogs and not associated with major complications. Further evaluation is required; however, in appropriately selected patients, LAS may offer the benefits of a minimally invasive technique, including a smaller incision and improved illumination and magnification during exploration and staging.
Abstract
OBJECTIVE
To compare the long-term outcomes of a ventral versus lateral surgical approach for mandibular and sublingual sialoadenectomy in dogs with a unilateral sialocele.
ANIMALS
46 client-owned dogs.
PROCEDURES
Medical records of dogs that underwent unilateral sialoadenectomy between 1999 and 2019 were retrospectively reviewed, and information was collected regarding signalment, clinical signs, historical treatment, swelling location, diagnostic imaging findings, sialoadenectomy approach, adjunctive treatments, intraoperative complications, hospitalization time, postoperative complications, recurrence, and contralateral sialocele development.
RESULTS
There were no significant differences in incidences of intraoperative complications, recurrence, or postoperative complications between dogs in which a lateral versus ventral approach was used. Clinically important intraoperative complications included iatrogenic tears in the oral mucosa, ligature slippage from the duct end, hemorrhage, and possible lingual nerve transection. Surgical experience was associated with the likelihood that intraoperative complications would develop. Suspected recurrence was reported in 2 of 26 (8%) dogs that underwent a lateral approach and 2 of 12 (17%) dogs that underwent a ventral approach. Hospitalization time was significantly shorter with the lateral approach than with the ventral approach. Postoperative complications had a short-term onset and occurred in 4 of 25 (16%) dogs that underwent a lateral approach and 3 of 12 (25%) dogs that underwent a ventral approach. Age and presence of a pharyngeal sialocele were associated with development of postoperative complications.
CLINICAL RELEVANCE
Long-term outcomes for ventral and lateral approaches to sialoadenectomy were favorable and appeared to be comparable. Further prospective study into potential associations of sialoadenectomy approach, age, and pharyngeal sialoceles on outcome is needed.
Abstract
OBJECTIVE To compare perioperative characteristics of dogs with cystic calculi treated via open versus laparoscopic-assisted cystotomy (LAC).
DESIGN Retrospective case series.
ANIMALS 89 client-owned dogs that underwent open cystotomy (n = 39) or LAC (50).
PROCEDURES Medical records of dogs that underwent cystotomy between 2011 and 2015 were reviewed. History, signalment, surgery date, results of physical examination, results of preoperative diagnostic testing, details of surgical treatment, duration of surgery, perioperative complications, treatment costs, and duration of hospitalization were recorded.
RESULTS 5 of 50 (10%) dogs required conversion from LAC to open cystotomy (OC). There was no significant difference between the LAC (1/50) and OC (2/39) groups with regard to percentage of patients with incomplete removal of calculi. Duration of surgery was not significantly different between the LAC (median, 80 min; range, 35 to 145 min) and OC (median, 70 min; range, 45 to 120 min) groups. Postoperative duration of hospitalization was significantly shorter for dogs that underwent LAC (median, 24 hours; range, 12 to 48 hours) versus OC (median, 26 hours; range, 12 to 63 hours). Surgical and total procedural costs were significantly higher for patients undergoing LAC.
CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that LAC may be an acceptable minimally invasive technique for treatment of cystic calculi in dogs. Surgery times were similar to those for dogs undergoing OC; however, surgical and total procedural costs were higher. Further investigation is suggested to determine which patients may benefit from LAC versus traditional OC.