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.     

Successful derotation of a splenic torsion in a racing greyhound

A two-year-old male racing greyhound was presented to the Sydney University Veterinary Hospital with a six-week history of intermittent gastric dilatation. Abdominal radiography and ultrasonography were suggestive of splenic torsion without gastric dilatation. Exploratory ceoliotomy confirmed a 540° clockwise rotation of the spleen. Derotation of the spleen was performed and thrombosis was not present in the splenic vessels. Epinephrine was injected into the splenic parenchyma to aid in splenic contraction. The spleen was left in situ. The greyhound made an uneventful recovery and has won several races in the 10-month follow-up period without further problems.     

Diagnosis of a large splenic tumor in a dog: computed tomography versus magnetic resonance imaging

This study demonstrated magnetic resonance imaging (MRI) and computed tomography for large-sized splenic hemangiosarcoma. Radiography and ultrasonography revealed the presence of a large-sized soft-tissue mass in the cranial abdomen. Computed tomography showed hypoattenuating mass. The mass was located in contact with liver, spleen and stomach, and the origin of the mass remained ambiguous. The mass was T2-hyperintense and T1-hypointense with mild contrast enhancement. MRI allowed a differentiation between large-sized tumor and neighboring normal structure, and the mass was consequently identified as arising from spleen. These results suggested that MRI might be a useful tool to visualize large-sized splenic tumors and improve the accuracy of diagnosis.     

COMPUTED TOMOGRAPHY DIAGNOSIS OF ISOLATED SPLENIC TORSION IN A DOG

Isolated splenic torsion in a dog was diagnosed using computed tomography (CT). The enlarged non enhanced spleen and a twisted soft tissue mass effect represented the rotated pedicle were the main findings. Abdominal radiography and ultrasonography were not conclusive.     

Diagnosis and surgical treatment of a primary splenic torsion in a domestic ferret (Mustela putorius furo)

A 4-year-old female spayed domestic ferret (Mustela putorius furo) presented with a history of vomiting over 24 hours. On physical examination, a significantly enlarged, firm spleen was palpated. Abdominal radiographs and abdominal ultrasound were suggestive of a splenic torsion or splenic infarction. An exploratory laparotomy confirmed the initial diagnosis and splenectomy was performed using a vessel sealing device. Histologic evaluation and culture of the spleen were consistent with primary torsion without evidence of infection or neoplasia. The patient recovered from surgery without complications. Based on a literature search, this is the first report of the clinical diagnosis and successful surgical treatment of a primary splenic torsion in a ferret. Although it appears to be a rare and potentially life-threatening disease in ferrets, splenic torsion should be considered as a differential diagnosis in ferrets that present with non-specific signs and a palpably enlarged spleen.     

Splenic torsion in an alpaca

OBJECTIVE: To describe the clinical signs, diagnostic evaluation and surgical management of an alpaca with splenic torsion. ANIMALS: Six-year-old female alpaca. RESULTS: Splenic torsion and uterine torsion were the inciting cause for persistent abdominal discomfort in this alpaca. Rectal examination, abdominocentesis, and transabdominal ultrasonographic findings were suggestive of a splenic lesion. Surgical management involved splenectomy of a necrotized spleen. CONCLUSIONS: Although rare in occurrence, splenic torsion should be considered as a potential cause of abdominal discomfort in alpacas. Splenectomy is a reasonable and successful method of treatment for a devitalized spleen secondary to splenic torsion in alpacas. CLINICAL RELEVANCE: Splenic torsion causes persistent abdominal discomfort in camelids and may be associated with uterine torsion. Rectal examination, transabdominal ultrasound and abdominocentesis are useful diagnostic tools to differentiate splenic torsion from other causes of abdominal discomfort. Splenectomy is an uncomplicated procedure in camelids and has a favorable prognosis.     

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.     

Laparoscopic Splenectomy for Treatment of Splenic Hemangiosarcoma in a Dog

Objective: To report laparoscopic splenectomy in a dog. Study Design: Clinical report. Animals: Mixed breed dog (n=1). Methods: Hemangiosarcoma was diagnosed by ultrasound‐guided fine‐needle aspiration of a splenic mass in an 11‐year‐old, 30 kg, mixed breed dog. No metastatic disease was identified during complete staging (chest radiographs, echocardiogram, and abdominal ultrasonography); however, cystic calculi were identified. Laparoscopic splenectomy using Ligasure V was performed through 3 portals and the calculi were removed by laparoscopic‐assisted cystoscopy. Results: Total surgical time was 2 hours and for laparoscopic splenectomy, 65 minutes. The celiotomy incision for splenic removal was 7 cm. The dog recovered uneventfully and was ambulatory 2 hours postoperatively. Conclusion: Laparoscopy with Ligasure V facilitated successful removal of a spleen with a 3 cm mass. Clinical Relevance: Laparoscopic splenectomy in dogs is feasible for removal of a normal‐sized spleen with a moderate‐sized mass.     

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.     

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.     

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.     

Bone haemangio-sarcoma in a young Belgian malinois

Bone haemangiosarcoma in a young Belgian malinois initially presented as an abscess involving the Tight 10th rib. The dog responded promptly to abscess drainage and antibiotics. Anaemia and thrombocytopenia began one week later and ultrasonography revealed splenic and liver lesions. Exploratory surgery identified tumour masses in the spleen, liver, lung and rib. Histopathological diagnosis was hemangiosarcoma, possibly of bone origin.     

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.     

Abdominal CT evaluation of the liver and spleen for staging mast cell tumors in dogs yields nonspecific results

Canine mast cell tumor staging is commonly performed using abdominal ultrasonography and fine‐needle aspiration cytology of masses, lymph nodes, and hepatic and splenic parenchyma. Computed tomography is used for abdominal, thoracic, or whole body imaging in staging mast cell tumors in the authors’ institution enabling evaluation of multiple body areas in one examination. The aim of this study was to compare the CT examinations acquired for staging of mast cell disease to their subsequent liver and spleen cytology findings. Medical records of dogs with primary mast cell tumors that underwent abdominal CT and concurrent liver and spleen aspirates were reviewed. The CT examinations were evaluated for attenuation, size, and margination of the liver and spleen. The relationship between CT findings and cytology results was analyzed. Forty‐nine dogs matched the inclusion criteria: five of forty‐nine dogs with cutaneous mast cell tumors were positive for metastasis from liver and/or spleen aspirates. Of the five dogs with cytological evidence of liver or spleen metastasis, four had normal CT liver attenuation and size, one dog had concurrent primary hepatocellular neoplasia, four dogs had abnormal splenic parenchyma (two nodular and two diffuse heterogeneity), and one dog had a normal attenuation of the spleen. In four dogs, the spleen was subjectively enlarged. Computed tomographic evaluation of the liver showed no consistent pattern associated with mast cell metastasis and did not predict cytology results. Multifocal splenic hypoattenuating lesions more commonly coincided with mast cell metastasis. Sampling of the liver and spleen remains to be considered in the absence of abnormal CT findings for full staging.     

Radiographic signs of isolated splenic torsion in dogs: eight cases (1980-1987)

Abdominal radiographs of 8 dogs with confirmed isolated splenic torsions were evaluated retrospectively. Radiographic signs included suboptimal abdominal detail, displacement of other abdominal organs, loss of visualization of the body of the spleen in its normal position (in the left cranial portion of the abdomen) on the ventrodorsal radiographic view, identification of the spleen in an abnormal location or shape, splenomegaly, and splenic gas. When the spleen location and shape could be identified as abnormal (3 dogs), the spleen appeared folded into a C shape in the central portion of the abdomen on the lateral radiographic view.     

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.     

QUANTITATIVE CONTRAST-ENHANCED ULTRASONOGRAPHY OF CANINE SPLEEN

Contrast-enhanced ultrasonography has an important role in the detection of tumors in humans. The second-generation contrast agent Sonazoid has the ability of real-time contrast imaging along with parenchymal imaging. The purposes of this study were to determine the effect and duration of Sonazoid on the changes in gray-scale enhancement of canine spleen and to establish an appropriate protocol for contrast-enhanced ultrasonography of canine spleen. Six healthy beagles were injected with an intravenous bolus of Sonazoid. In the spleen parenchyma, the enhancement was maintained up to 30 min after injection. Moreover, for 5–22 s after injection, gray-scale enhancement of splenic arteries afforded arterial imaging. Perfusion of the kidney may be investigated from 3.6 s to 3.5 min after injection of Sonazoid. These results suggest that Sonazoid is applicable to canine spleen parenchymal imaging and that the optimal time for the parenchymal imaging is 7–30 min after injection. The findings of this quantitative study should prove useful in the evaluation of diffuse or focal splenic and renal diseases in dogs.     

USE OF TRANSSPLENIC INJECTION OF AGITATED SALINE AND HEPARINIZED BLOOD FOR THE ULTRASONOGRAPHIC DIAGNOSIS OF MACROSCOPIC PORTOSYSTEMIC SHUNTS IN DOGS

We describe the use of ultrasonography‐guided percutaneous splenic injection of agitated saline and heparinized blood for the diagnosis of portosystemic shunts (PSS) in 34 dogs. Agitated saline mixed with 1 ml of heparinized autologous blood was injected into the spleen of 34 sedated dogs under sonographic guidance. The transducer was then sequentially repositioned to visualize the portal vein, the caudal vena cava, and the right atrium through different acoustic windows. It was possible to differentiate between intrahepatic and extrahepatic shunts depending on the entry point of the microbubbles into the caudal vena cava. Portoazygos shunts and portocaval shunts could be differentiated based on the presence of microbubbles in the caudal vena cava and/or the right atrium. In one dog, collateral circulation due to portal hypertension was identified. In dogs with a single extrahepatic shunt, the microbubbles helped identify the shunting vessel. The technique was also used postoperatively to assess the efficacy of shunt closure. All abnormal vessels were confirmed by exploratory laparotomy or with ultrasonographic identification of the shunting vessel. Ultrasound‐guided transsplenic injection of agitated saline with heparinized blood should be considered as a valuable technique for the diagnosis of PSS; it is easy to perform, safe, and the results are easily reproducible.