case_images: PMC9247579_01
case_images: Right lateral projection of the abdomen. An ovoid-shaped, soft-tissue opacity mass (asterisk) caudodorsal to the urinary bladder was noted, causing a narrowing of the descending colonic lumen (dotted line).
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case_images: F1
case_images: Toshiba, Tochigi, Japan) of the right lateral, left lateral, and ventrodorsal projections was performed while the cat was awake, and a large, well-defined, ovoid-shaped, soft tissue opacity mass was observed caudodorsal to the urinary bladder at the sixth lumbar vertebra to the sacrum level, causing dorsal displacement, and narrowing of the descending colon (Figure 1). The mass was approximately 3.1 cm in height and 3.6 cm in length in the right lateral abdominal projection.
case_images: (A) Transverse plane ultrasound image of the descending colon. A hyperechoic mass (asterisk) with heteroechogenicity between the submucosal and muscular layers of the descending colon was seen. (B) Sagittal plane ultrasound image of the colonic lymph nodes (0.6 cm in thickness and 0.9 cm in length). The colonic lymph nodes (arrow) adjacent to the mass (asterisk) appeared enlarged and hypoechogenic. (C) Follow-up sagittal plane ultrasound image of the descending colon 2 weeks after surgical evacuation. No mass effect was noted at the affected site. The intestinal layering (arrow) was relatively normal, with a thickened and corrugated mucosal layer. (D) Follow-up sagittal plane ultrasound image of colonic lymph nodes 2 weeks after surgical evacuation. The colonic lymph nodes (arrows) were smaller (0.4 cm in thickness and 0.7 cm in length) and with homogeneous echogenicity.
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case_images: F2
case_images: Considering the location and echogenicity of the mass, colonic intramural neoplasia with regional colonic lymphadenopathy was mainly suspected, whereas abscess and hematoma could not be completely excluded (Figures 2A,B). Ann Animal Hospital revealed that the affected colon appeared to display normal layering with thickened and corrugated mucosa. The colonic lymph nodes showed homogeneous echogenicity and smaller size than before (0.4 cm in thickness and 0.7 cm in length; Figures 2C,D). A follow-up CT (Aquilion, Toshiba Medical Systems Corporation, Tochigi, Japan) (Figures 3C,D), colonoscopy (Figure 4C), and laboratory examination were performed 1 month later, and showed no mass effect or abnormality during the examinations, while globulin content returned to normal levels and blood coagulation was normal.
case_images: (A) Transverse and (B) dorsal plane CT images revealed intramural masses (arrows) in the descending colon. Hyperattenuating contents accumulated on the gravity-dependent side of the mass, exhibiting two different layers within the mass with a clear interface. The whole descending colon was deviated to the right on the pre-treatment CT images. (C)Transverse and (D) dorsal plane CT images obtained 1-month post-treatment. Normal colonic intestinal layering was noted, while the colonic lymph nodes (not shown) appeared normal in size and attenuation. The descending colon was located in the left caudal abdominal cavity. The patient's right side is shown on the left image.
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case_images: F3
case_images: Unit, HU) accumulating on the gravity-dependent side and lower attenuating contents (30-40 HU) on the upper side (Figures 3A,B). Ultrasound-guided fine-needle aspiration was performed, and ~8 ml of non-agglutinated blood was drained. Ann Animal Hospital revealed that the affected colon appeared to display normal layering with thickened and corrugated mucosa. The colonic lymph nodes showed homogeneous echogenicity and smaller size than before (0.4 cm in thickness and 0.7 cm in length; Figures 2C,D). A follow-up CT (Aquilion, Toshiba Medical Systems Corporation, Tochigi, Japan) (Figures 3C,D), colonoscopy (Figure 4C), and laboratory examination were performed 1 month later, and showed no mass effect or abnormality during the examinations, while globulin content returned to normal levels and blood coagulation was normal.
case_images: A colonoscopy was performed after a CT examination. (A) A round submucosal mass (arrow) with an intact mucosa was noticed at the descending colon, causing narrowing of the colonic lumen. (B) The colonoscopic image obtained after surgical evacuation of the contents in the mass: the incision wound (arrow) was kept open for drainage of the remaining blood clots. (C) Image of a follow-up colonoscopy 1 month after evacuation: the incision wound was well-healed, and no recurrence was seen. (D) Pathology of the colonic specimen showed chronic proctitis and lymphoid hyperplasia of the colon. A small number of lymphocytes and plasma cells with fewer neutrophils are noted multifocally in the lamina propria of colon (H&E stain, bar = 50 mum, 400x).
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case_images: F4
case_images: Animal Hospital, and a mass with an intact mucosal surface and spotty oozing blood was observed (Figure 4A). Colonoscopy was reperformed to ensure that there was no active bleeding after surgical evacuation and biopsy (Figure 4B). The patient was diagnosed as chronic proctitis with lymphoid hyperplasia (Figure 4D). Ann Animal Hospital revealed that the affected colon appeared to display normal layering with thickened and corrugated mucosa. The colonic lymph nodes showed homogeneous echogenicity and smaller size than before (0.4 cm in thickness and 0.7 cm in length; Figures 2C,D). A follow-up CT (Aquilion, Toshiba Medical Systems Corporation, Tochigi, Japan) (Figures 3C,D), colonoscopy (Figure 4C), and laboratory examination were performed 1 month later, and showed no mass effect or abnormality during the examinations, while globulin content returned to normal levels and blood coagulation was normal.
case_images: A brief timeline of the medicine intervention in the cat. Clinical signs presented 3 days prior to first visit. Radiography, ultrasonography, and CT examination were performed on the same day of the first visit. Palliative medication was administrated for 7 days. The surgical intervention was performed 7 days later. Post-operative medicine was administrated for 2 weeks. The patient revisited on day 22. A follow-up CT scan and colonoscopy were conducted 1 month later. After 14 months, a final telephone interview was conducted.
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case_images: F5
case_images: The timeline of medical interventions is illustrated in Figure 5.