THE HILAR PERIVENOUS HYPERECHOIC TRIANGLE AS A SIGN OF ACUTE SPLENIC TORSION IN DOGS

Diagnosis of acute primary splenic torsion is challenging. The ultrasonographic appearance of this condition has been described, but other splenic diseases, such as diffuse infarction because of thrombosis, can appear very similar. We describe an additional ultrasonographic sign of acute splenic torsion; a triangular hyperechoic area at the hilus between the veins and the splenic parenchyma that is continuous with the hyperechoic mesentery. In a group of animals where acute splenic torsion was part of the ultrasound report differential diagnosis, we compared findings in dogs with torsion with findings in dogs with other splenic conditions. The presence of a hilar hyperechoic perivenous triangle was significantly associated with splenic torsion (P = 0.005). We speculate that this sign is associated with torsion because of the secondary severe, diffuse splenic enlargement. Although not pathognomonic, this sign could be used to more accurately diagnose splenic torsion in light of other findings consistent with this condition.     

Chronic primary splenic torsion with peritoneal adhesions in a dog: case report and literature review

Primary splenic torsion in dogs is uncommon and can occur in acute or chronic form. The chronic form is difficult to diagnose because the clinical signs are vague and sometimes intermittent. A dog with a history of diaphragmatic hernia repair two years previously presented with chronic, vague clinical signs and an abdominal mass. The mass was revealed to be spleen on ultrasonography. On exploratory laparotomy, the dog was found to have a splenic torsion of approximately 180 degrees with mature, fibrous adhesions retaining the spleen in a torsed position. A splenectomy was performed, and the dog recovered uneventfully with complete resolution of prior clinical signs. Prognosis for dogs with splenic torsion is good, although complications are relatively common.     

Use of a vessel sealant device for splenectomy in dogs

Objective: To (1) describe a technique for splenic vessel hemostasis and (2) report complications and outcome after use of bipolar sealant device during splenectomy in dogs. Study Design: Case series. Animals: Dogs (n=27) with naturally occurring splenic disease. Methods: Between January 2006 and March 2008, splenectomy was performed using a vessel sealant device in 27 dogs with naturally occurring splenic disease. Number of sutures needed for splenectomy and complications were recorded. Splenic artery diameter was measured using a caliper. Intraoperative hemostasis, device ease of use, postoperative hemorrhage, and short‐term survival were evaluated. Results: Splenectomy was performed successfully in 27 dogs with the vessel sealant device; none of the dogs required vessel ligation with suture. The splenic artery was dissected and adequately sealed in each dog. One dog was readmitted 4 days after surgery with hemoabdomen. Abdominal exploration revealed splenic pedicle hemorrhage and pancreatitis, the vessel sealant device was used to coagulate splenic pedicle bleeding. The dog was alive at suture removal. Conclusion: In dogs, a vessel sealant device may be used to achieve efficient and safe hemostasis of the splenic vascular pedicle without sutures.     

Radiographic findings and clinical factors in dogs with surgically confirmed or presumed colonic torsion

Colonic torsion is a life‐threatening condition in dogs and radiographic findings for this condition have not been well described. The purpose of this retrospective case series was to describe radiographic findings and clinical signs in a group of dogs with colonic torsion. Inclusion criteria were dogs presenting during the period of 2006 and 2016, and that had abdominal radiography and a surgically confirmed or presumed diagnosis of colonic torsion. For each dog, clinical data were recorded from medical records and imaging findings were recorded from retrieved plain radiographs and positive contrast radiographs in which barium enema was performed. Fourteen dogs met inclusion criteria. Of these, nine dogs had colonic torsion confirmed at surgery, with five dogs having surgical confirmation of colonic congestion or mesenteric torsion. Radiographic findings included segmental distention of the colon (14/14), focal narrowing of the colon (11/14), displacement of cecum (11/14), displacement of descending colon (14/14), and mild to no small intestinal distention (14/14). In cases where barium enema was performed, focal narrowing of the colon and longitudinal striations that course in a helical pattern were identified, termed the “torsion sign.” Vomiting was the most common clinical sign observed (12/14), followed by abdominal pain in a small majority of cases (8/14). Severe abdominal pain and hypovolemic shock were uncommon in the patients reported (3/14). Colonic torsion should be considered as a differential diagnosis for dogs with radiographic segmental colonic distention with displacement of the descending colon and cecum. Barium enema is recommended for more definitive diagnosis.     

Gastric ulceration subsequent to partial invagination of the stomach in a dog with gastric dilatation-volvulus

CASE DESCRIPTION-An 8-year-old castrated male German Shepherd Dog was evaluated because of abdominal distension, retching, and vomiting. CLINICAL FINDINGS-Gastric dilatation-volvulus was suspected on the basis of the dog's signalment, history, clinical signs, and results of clinicopathologic analyses and abdominal radiography. Celiotomy was performed, and gastric dilatation-volvulus was confirmed along with splenomegaly. Gastric invagination was performed over an area of gastric necrosis. The dog was reevaluated 21 days later after an episode of collapse. Findings of physical examination and clinicopathologic analyses were suggestive of internal hemorrhage. Abdominal ultrasonography and subsequent celiotomy revealed severe gastric ulceration at the gastric invagination site, splenic torsion, and a focal splenic infarct. TREATMENT AND OUTCOME-Splenectomy and gastrectomy of the necrotic tissue were performed. The dog was discharged from the hospital, and the owner was instructed to administer gastroprotectants and feed the dog a bland diet. The dog was reported to be healthy 3.25 years after surgery. CLINICAL RELEVANCE-Findings suggest that complications associated with the gastric invagination procedure include severe gastric ulceration that may require subsequent surgery. Prolonged treatment with gastroprotectants following gastric invagination surgery may be necessary to avoid gastric ulceration in dogs.     

SONOGRAPHIC AND RADIOGRAPHIC CHANGES ASSOCIATED WITH SPLENIC TORSION IN THE DOG

The clinical, radiographic, and sonographic signs in three dogs with splenic torsion are presented. AH dogs exhibited weight loss, anorexia, and lethargy. Splenomegaly was consistent radiographic finding in two dogs and large ill-defined midabdominal mass was seen in one dog. The spleen was easily imaged sonographically in all dogs. Splenic sonography in two dogs showed diffuse, hypoechoic pattern consistent with splenic congestion. Hilar splenic vessels were enlarged on the sonograms of two dogs.     

Splenic marginal zone lymphoma in 5 dogs (2001-2008)

Background: Splenic marginal zone lymphomas (MZL) in dogs arise from the marginal zone of B‐cell follicles and can progress slowly. Objectives: To describe clinical features, treatment, and outcome of dogs with splenic MZL. Animals: Five dogs with naturally occurring MZL. Methods: Clinical, laboratory, and follow‐up data were retrospectively reviewed. Diagnosis was based on clinical, histopathological, and immunophenotypic features. Results: All dogs had stage IV disease; among them, 2 were symptomatic (substage “b”) because of splenic rupture. Four dogs underwent splenectomy and adjuvant doxorubicin, and 1 dog underwent surgery only. Three out of the 4 dogs treated with surgery and chemotherapy died of causes unrelated to lymphoma, after 760, 939, and 1,825 days, whereas the remaining dog was alive and in complete remission after 445 days. The dog not receiving any adjuvant treatment had recurrence of the tumor after 180 days. Conclusions and Clinical Importance: Splenic MZL appears indolent and can benefit from splenectomy, with or without systemic chemotherapy.     

Splenomegaly in Dogs

Splenomegaly confirmed by surgery or necropsy in 100 dogs was diagnosed histologically as benign neoplasia (n = 1), primary splenic malignancy (n = 59), neoplastic metastases (n = 6), and nonneoplastic disease (n = 34). Dogs with known systemic disease, such as lymphoma and mast cell tumor, that caused splenomegaly were not included in the study. Hemangiosarcoma was the most common splenic disease (43 cases). Overall mean age of the dogs was 10.7 years, the most common breed was German Shepherd dog, and 72 of the dogs weighed more than 21 kg. Dogs with anemia, nucleated red blood cells, abnormal red blood cell morphology, or splenic rupture had a significantly greater chance of having splenic neoplasia (P less than 0.002). A multivariable logistic regression analysis found that the presence of anemia and splenic rupture in dogs with splenomegaly was up to 69% accurate in predicting presence of splenic neoplasia. After splenectomy, the median survival time of dogs with splenic neoplasia was 13 weeks. For dogs with nonneoplastic splenomegaly it was at least 36 weeks.     

Resolution of severe thrombocytopenia in two standard Poodles with surgical correction of splenic torsion

Objective: To describe the diagnosis and treatment of 2 cases of severe thrombocytopenia associated with splenic torsion and to discuss the pathophysiologic mechanisms underlying the thrombocytopenia. Summary: We report 2 cases of severe thrombocytopenia associated with splenic torsion. Each dog presented with non‐specific clinical signs, radiographic evidence of an intra‐abdominal mass, and platelet counts of less than 25,000 platelets/μL. The diagnosis of splenic torsion was made with abdominal ultrasonography and was confirmed during exploratory laparotomy. Both dogs recovered rapidly following splenectomy. The cause of thrombocytopenia associated with splenic torsion is not fully elucidated, but may be because of either platelet sequestration within the torsed spleen, platelet consumption in disseminated intravascular coagulation, or a combination of both. New information provided: This report provides previously unreported evidence that the degree of thrombocytopenia associated with splenic torsion may be of a severity at which primary hemostasis is compromised, and resolution of thrombocytopenia occurs after splenectomy.     

CT characteristics of primary splenic torsion in eight dogs

Splenic torsion is a rare potentially life‐threatening condition characterized by rotation of the spleen around the gastrosplenic and phrenosplenic ligaments leading to occlusion of venous drainage and arterial supply. This retrospective study describes the CT characteristics for dogs with surgically confirmed splenic torsion from 2013 to 2018 using the submissions to a large multinational teleradiology database. Eight dogs had the splenic torsion confirmed with surgery. Seven of eight cases had histology confirming congestion, hemorrhage, and necrosis, and one had concurrent myelolipoma infiltration. The CT characteristics included an enlarged (8/8), rounded (7/8), folded C‐shaped spleen (8/8) with a difference of median parenchymal attenuation between pre‐ and postcontrast of +1.15 HU (Hounsfield units). Other common features included a mainly homogeneous parenchyma on pre‐ and post‐contrast images (6/8), lack of subjective and objective vascular and parenchymal contrast enhancement (6/8) and free peritoneal fluid (6/8). A “whirl sign” was seen in the majority of cases (7/8) alongside a strongly hyperattenuating center (95‐416 HU) on the precontrast images (5/7), which has not been previously described in the veterinary literature. Gastric position was normal in all cases. More variable CT characteristics of the confirmed torsions were attributable to suspected partial torsion and myelolipomatous infiltration. Overall, primary splenic torsion confirmed with surgery showed consistent characteristics on CT.     

CT findings in five dogs with surgically confirmed colonic torsion

Colonic torsion is a life‐threatening condition that results in colonic ischemia, necrosis, perforation, sepsis, and eventual death. The aim of this multicenter, retrospective case series study was to describe the CT findings in dogs with surgically confirmed colonic torsion. Medical records were searched for dogs with surgically confirmed colonic torsion following abdominal CT. Five dogs met the inclusion criteria. Three had a history of chronic intermittent diarrhea prior to presentation. Two dogs presented with acute vomiting, diarrhea, and abdominal pain and one dog presented with acute vomiting and lethargy. Computed tomographic findings in all dogs with surgically confirmed colonic torsion include: “whirl sign,” displacement and distension of the cecum and colon, focal narrowing of the colon, and distension of the mesenteric vasculature in all dogs (5/5); streaky peritoneal fat and peritoneal effusion (4/5), pneumatosis coli (2/5), small intestinal distension (2/5), portal vein thrombosis (1/5), and reduced colonic wall contrast enhancement (1/5). In all dogs (5/5), the torsion site was the descending colon and demonstrated an anticlockwise rotation. At surgery, three of the five dogs had a partial colonic torsion with hyperemia at the site of obstruction and two of the five dogs had a complete torsion with marked necrosis of the colonic wall. Displacement of the colon and cecum, segmental distension and focal narrowing of the colon, the presence of a “whirl sign” and distension of the mesenteric vasculature are CT findings highly suggestive of colonic torsion.     

Intestinal Entrapment and Strangulation Caused by Rupture of the Duodenocolic Ligament in Four Dogs

Objective — The purpose of this study was to describe four dogs with intestinal entrapment and strangulation caused by a rupture of the duodenocolic ligament.
Study Design — This case series documents historical findings, physical examination findings, diagnostic workup, surgical intervention, and outcome of four dogs confirmed at surgery with duodenocolic ligament rupture.
Results — Three of four dogs were German shepherds, and two of three German shepherds were intact males. The history, clinical signs, and physical examination findings were not specific for intestinal entrapment. The clinical signs in three of four dogs included chronic vomiting, diarrhea, anorexia, and lethargy. In the remaining dog, the clinical signs were vomiting and peracute collapse. This dog rapidly deteriorated over a few hours because of strangulation of the entrapped intestines. In two of four dogs, abdominal radiographs showed a distended colon displaced to the right side of the abdominal cavity. Surgery involved transection of the remaining ventral remnant of the duodenocolic ligament and replacing the colon into its normal anatomic position. The three dogs with chronic clinical signs were either still alive, or were euthanatized for unrelated problems. The dog with strangulation of the entrapped intestines was euthanatized at the time of surgery.
Conclusions and Clinical Relevance — Duodenocolic ligament rupture with secondary bowel entrapment can occur in dogs. The prognosis for these animals is favorable provided there is no vascular compromise of the entrapped bowel segments. The peracute history, progression of the disease process, and outcome of the fourth dog in this study indicate that surgery should be performed as an emergency procedure.     

Use of an ultrasonically activated scalpel for splenectomy in 10 dogs with naturally occurring splenic disease

OBJECTIVE:To evaluate the safety and efficacy of an ultrasonically activated scalpel for performing splenectomy, with minimal ligation, in dogs. STUDY DESIGN: Prospective clinical study. ANIMALS: Dogs (10) with naturally occurring splenic disease. METHODS: Between October 2003 and February 2004, splenectomy was performed using an ultrasonically activated scalpel and a double seal method, in 10 dogs with naturally occurring splenic disease. Time for splenectomy and number of ligatures required were recorded. Intraoperative hemostasis, device ease of use, postoperative hemorrhage, and short-term survival were evaluated. RESULTS: Mean operative time for splenectomy, exclusive of celiotomy and closure, was 18 minutes (range, 8-25 minutes). The mean number of ligatures needed to perform splenectomy was 1 (range, 0-2 ligatures). One dog hemorrhaged from the splenic vein after ultrasonic scalpel transection of a vessel >5-mm diameter and required a ligature. The ultrasonic scalpel was easy to use, with a minimal learning curve. None of the dogs had postoperative abdominal hemorrhage; 9 dogs were discharged and 1 dog was euthanatized because of septicemia. CONCLUSION: Ultrasonic activated scalpel may be used to achieve efficient and safe hemostasis of the splenic vascular pedicle in dogs with minimal need for vascular ligation. CLINICAL RELEVANCE: Ultrasonic scalpels can be used to perform splenectomy in dogs with naturally occurring splenic disease.     

Lung lobe torsion in dogs: 22 cases (1981-1999)

OBJECTIVE: To identify breed disposition, postoperative complications, and outcome in dogs with lung lobe torsion. DESIGN: Retrospective study. ANIMALS: 22 client-owned dogs. PROCEDURE: Information on signalment; history; clinical findings; results of clinicopathologic testing, diagnostic imaging, and pleural fluid analysis; surgical treatment; intra- and postoperative complications; histologic findings; and outcome were obtained from medical records. RESULTS: All 22 dogs had pleural effusion; dyspnea was the most common reason for examination. Fifteen dogs were large deep-chested breeds; 5 were toy breeds. Afghan Hounds were overrepresented, compared with the hospital population. One dog was euthanatized without treatment; the remaining dogs underwent exploratory thoracotomy and lung lobectomy. Eleven dogs recovered from surgery without complications, but 3 of these later died of thoracic disease. Four dogs survived to discharge but had clinically important complications within 2 months, including chylothorax, mediastinal mesothelioma, gastric dilatation, and a second lung lobe torsion. Six dogs died or were euthanatized within 2 weeks after surgery because of acute respiratory distress syndrome, pneumonia, septic shock, pneumothorax, or chylothorax. Chylothorax was diagnosed in 8 of the 22 dogs, including 4 Afghan Hounds. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that lung lobe torsion is rare in dogs and develops most frequently in large deep-chested dogs, particularly Afghan Hounds. Other predisposing causes were not identified, but an association with chylothorax was evident, especially in Afghan Hounds. Prognosis for dogs with lung lobe torsion was fair to guarded.     

B-MODE AND DOPPLER ULTRASOUND IMAGING OF THE SPLEEN WITH CANINE SPLENIC TORSION: A RETROSPECTIVE EVALUATION

The ultrasonographic appearance of splenic torsion has been described; the splenic parenchyma can be normal, hypoechoic or anechoic with interspersed linear echoes (coarse/"lacy" appearance). The ultrasonographic parenchymal appearance of 15 dogs in this report with splenic torsion varied: mottled hypoechoic regions (n=2), diffusely hypoechoic (n=11) and normal (n=2). Because splenic torsion causes vascular congestion due to splenic vein compression and eventual thrombosis, visible splenic vein intraluminal echogenicities compatible with thrombi were seen in 13 dogs using B-mode. Using spectral Doppler and color Doppler imaging of the splenic veins, no measurable flow velocities were detected in any of the 15 dogs. The varied B-mode ultrasonographic appearance of the splenic veins for intraluminal echoes and spectral or color Doppler evaluation for absent velocity flow.     

Splenic Infarction in 16 Dogs: A Retrospective Study

Sixteen dogs with splenic infarction due to causes other than splenic torsion were identified. Dogs with splenic infarction often had multiple concurrent diseases, and surgical management of splenic infarction was associated with high mortality. Splenic infarction occurred in dogs with hypercoagulable conditions associated with liver disease, renal disease, and hyperadrenocorticism, or as a consequence of uniform splenomegaly, neoplasia, or thrombosis associated with cardiovascular disease. Clinical signs and common laboratory findings generally reflected the underlying disease process. A variety of splenic abnormalities were detected by abdominal ultrasound in 15 dogs, with the ventral extremity of the spleen being most often abnormal. Four dogs were euthanized or died because of the presence of severe systemic disease, whereas 12 dogs underwent laparotomy. Complete splenectomy was performed in 9 dogs and partial splenectomy was performed in 2 dogs. Seven dogs died in the immediate postoperative period, 3 required chronic veterinary care, and 2 had uncomplicated long-term recoveries. Splenic infarction should be regarded as a sign of altered blood flow and coagulation, rather than as a primary disease, and surgical management should be reserved for patients with life-threatening complications such as hemoabdomen or sepsis.     

Fundic gastropexy for prevention of recurrence of gastric volvulus

After non-surgical primary treatment (aspiration) of gastric torsion 189 dogs underwent fundupexy to prevent recurrence. The fundic surface of the stomach was subjected to diathermy spot coagulation after which the fundus was fixed in its normal position against the diaphragm using non-absorbable sutures in several rows. Of the 189 dogs operated on two died from intercurrent disease within eight days. Of the 187 dogs which were discharged from the clinic 144 (77 per cent) were available for follow-up. The median follow-up period was 31 months and 28 dogs had a follow-up of between five and eight years. Two of the dogs were destroyed within a year postoperatively because of recurring tympanism and a third dog after one-and-a-half years because of recurrent diarrhoea. The general condition was unaffected in the remaining 141 dogs.     

Ventricular Arrhythmias in Dogs Undergoing Splenectomy: A Prospective Study

Fifty dogs undergoing splenectomy for splenic masses (n = 40), torsion of the splenic pedicle (n = 5), and immune-mediated disease (n = 5) were evaluated preoperatively and postoperatively for ventricular arrhythmias and the relationship between ventricular arrythmia and splenic disease. The ability of 1 -minute electrocardiograms recorded every 6 hours (ECGs/q6hr) to detect ventricular arrythmia was compared with continuous 48-hour Holter monitoring. Based on continuous Holter monitoring, splenectomized dogs had a high incidence (22 of 50) of rapid ventricular tachycardia. The incidence of rapid ventricular tachycardia was significantly higher in dogs with ruptured splenic masses (16 of 23) than without rupture (1 of 17) ( P < .001). When the results of ECG/q6hr were compared with the results of continuous Holter monitoring, ECG/q6hr was normal in 29% (4 of 14) of dogs with rapid ventricular tachycardia at > 3,000 ventricular extrasystoles (VE)/hr; 50% (4 of 8) of dogs with rapid ventricular tachycardia at 1,000 to 3,000 VE/hr and 100% (6 of 6) of dogs with 10 to 300 VE/hr without rapid ventricular tachycardia. Although dogs undergoing splenectomy had a high incidence of ventricular arrythmias, one-minute ECGs/q6h were unreliable for detection of ventricular arrythmias even when high-frequency extrasystoles occurred.