Ultrasonography and noncontrast computed tomography of medial retropharyngeal lymph nodes in healthy cats

Sarah Nemanic Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.

Search for other papers by Sarah Nemanic in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
and
Nathan C. Nelson Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.
Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.

Search for other papers by Nathan C. Nelson in
Current site
Google Scholar
PubMed
Close
 DVM, MS

Abstract

Objective—To determine various measurements of medial retropharyngeal lymph nodes (MRPLNs) in healthy cats via ultrasonography and CT.

Animals—45 cats (age range, 2 to 8 years).

Procedures—Cats underwent CT of the head and ultrasonography of the cervical region. Various measurements of MRPLNs were obtained, and parenchymal heterogeneity, presence of a hilus, appearance of margins, and attenuation of MRPLNs were determined.

Results—Data for 7 cats were excluded because they did not meet inclusion criteria; data for 38 cats were evaluated. Measurements of left and right MRPLNs were not significantly different. Mean length × rostral height × rostral width dimensions of MRPLNs were 20.7 × 12.4 × 3.7 mm and 20.7 × 13.1 × 4.7 mm in ultrasonographic and CT images, respectively. Maximum MRPLN dimensions were approximately 32 × 20 × 7 mm. Mean attenuation of MRPLNs was 40.2 Hounsfield units. Parenchyma of MRPLNs was mildly (via CT) to moderately (via ultrasonography) heterogeneous. A hilus was identified in 95% (via ultrasonography) and 24% or 92% (via CT [depending on criteria used to define a hilus]) of MPRLNs. Lymph node margins were smooth in CT images and mildly irregular in ultrasonographic images. A negative linear correlation was detected between age of cat and MRPLN volume.

Conclusions and Clinical Relevance—MRPLNs in cats were easily imaged via ultrasonography and CT. Left and right MRPLNs were symmetric, and MRPLNs were larger in young adult cats versus old cats. Data were intended to serve as references for evaluation of MRPLNs in healthy cats.

Abstract

Objective—To determine various measurements of medial retropharyngeal lymph nodes (MRPLNs) in healthy cats via ultrasonography and CT.

Animals—45 cats (age range, 2 to 8 years).

Procedures—Cats underwent CT of the head and ultrasonography of the cervical region. Various measurements of MRPLNs were obtained, and parenchymal heterogeneity, presence of a hilus, appearance of margins, and attenuation of MRPLNs were determined.

Results—Data for 7 cats were excluded because they did not meet inclusion criteria; data for 38 cats were evaluated. Measurements of left and right MRPLNs were not significantly different. Mean length × rostral height × rostral width dimensions of MRPLNs were 20.7 × 12.4 × 3.7 mm and 20.7 × 13.1 × 4.7 mm in ultrasonographic and CT images, respectively. Maximum MRPLN dimensions were approximately 32 × 20 × 7 mm. Mean attenuation of MRPLNs was 40.2 Hounsfield units. Parenchyma of MRPLNs was mildly (via CT) to moderately (via ultrasonography) heterogeneous. A hilus was identified in 95% (via ultrasonography) and 24% or 92% (via CT [depending on criteria used to define a hilus]) of MPRLNs. Lymph node margins were smooth in CT images and mildly irregular in ultrasonographic images. A negative linear correlation was detected between age of cat and MRPLN volume.

Conclusions and Clinical Relevance—MRPLNs in cats were easily imaged via ultrasonography and CT. Left and right MRPLNs were symmetric, and MRPLNs were larger in young adult cats versus old cats. Data were intended to serve as references for evaluation of MRPLNs in healthy cats.

Contributor Notes

Dr Nemanic's present address is Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331.

Supported by the Endowed Research Funds Grant, College of Veterinary Medicine, Michigan State University.

Presented as an oral presentation at the American College of Veterinary Radiology Annual Meeting, Asheville, NC, August 2010.

The authors thank Joseph Hauptman and Greg Habing for assistance with statistical analyses.

Address correspondence to Dr. Nemanic (sarah.nemanic@oregonstate.edu).
  • 1.

    Evans HEMiller ME. Miller's anatomy of the dog. Philadelphia: WB Saunders, 1993:726727.

  • 2.

    Herring ESSmith MMRobertson JL. Lymph node staging of oral and maxillofacial neoplasms in 31 dogs and cats. J Vet Dent 2002; 19:122126.

  • 3.

    Saito HSato TYamashita Y, et al. Topographical analysis of lymphatic pathways from the meso- and hypopharynx based on minute cadaveric dissections: possible application to neck dissection in pharyngeal cancer surgery. Surg Radiol Anat 2002; 24:3849.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 4.

    Lurie DMSeguin BSchneider PD, et al. Contrast-assisted ultrasound for sentinel lymph node detection in spontaneously arising canine head and neck tumors. Invest Radiol 2006; 41:415421.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 5.

    Castelijns JAvan den Brekel MW. Imaging of lymphadenopathy in the neck. Eur Radiol 2002; 12:727738.

  • 6.

    Murakami SYamanishi MWAzuma R. Lymph node abscess due to Actinomyces viscosus in a cat. J Vet Med Sci 1997; 59:10791080.

  • 7.

    Steinkamp HJCornehl MHosten N, et al. Cervical lymphadenopathy: ratio of long- to short-axis diameter as a predictor of malignancy. Br J Radiol 1995; 68:266270.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 8.

    Nyman HTKristensen ATSkovgaard IM, et al. Characterization of normal and abnormal canine superficial lymph nodes using greyscale B-mode, color flow mapping, power and spectral Doppler ultrasonography—a multivariate study. Vet Radiol Ultrasound 2005; 46:404410.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 9.

    Nyman HTO'Brien RT. The sonographic evaluation of lymph nodes. Clin Tech Small Anim Pract 2007; 22:128137.

  • 10.

    Nyman HTKristensen ATFlagstad A, et al. A review of the sonographic assessment of tumor metastases in liver and superficial lymph nodes. Vet Radiol Ultrasound 2004; 45:438448.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 11.

    Salwei RMO'Brien RTMatheson JS. Characterization of lymphomatous lymph nodes in dogs using contrast harmonic and power Doppler ultrasound. Vet Radiol Ultrasound 2005; 46:411416.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 12.

    Sato AFSolano M. Ultrasonographic findings in abdominal mast cell disease: a retrospective study of 19 patients. Vet Radiol Ultrasound 2004; 45:5157.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 13.

    Karnik KReichle JKFischetti AJ, et al. Computed tomographic findings of fungal rhinitis and sinusitis in cats. Vet Radiol Ultrasound 2009; 50:6568.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 14.

    Gendler ALewis JRReetz JA, et al. Computed tomographic features of oral squamous cell carcinoma in cats: 18 cases (2002–2008). J Am Vet Med Assoc 2010; 236:319325.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 15.

    Burns GOScrivani PVThompson MS, et al. Relation between age, body weight, and medial retropharyngeal lymph node size in apparently healthy dogs. Vet Radiol Ultrasound 2008; 49:277281.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 16.

    Kneissl SProbst A. Comparison of computed tomographic images of normal cranial and upper cervical lymph nodes with corresponding E12 plastinated-embedded sections in the dog. Vet J 2007; 174:435438.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 17.

    Kneissl SProbst A. Magnetic resonance imaging features of presumed normal head and neck lymph nodes in dogs. Vet Radiol Ultrasound 2006; 47:538541.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 18.

    Wiggs RBLobprise HB. Veterinary dentistry: principles and practice. Philadelphia: Lippincott-Raven Publishers, 1997;196.

  • 19.

    Ying MPang BFS. Three-dimensional ultrasound measurement of cervical lymph node volume. Br J Radiol 2009; 82:617625.

  • 20.

    Doros GLew R. Design based on intra-class correlation coefficients. Am J Biostat 2010; 6:18.

  • 21.

    Kinns JMai W. Association between malignancy and sonographic heterogeneity in canine and feline abdominal lymph nodes. Vet Radiol Ultrasound 2007; 48:565569.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 22.

    Sakai OCurtin HDRomo LV, et al. Radiologic evaluation of the neck lymph node pathology benign proliferative, lymphoma, and metastatic disease. Radiol Clin North Am 2000; 38:979998.

    • Search Google Scholar
    • Export Citation
  • 23.

    Pugh CR. Ultrasonographic examination of abdominal lymph nodes in the dog. Vet Radiol Ultrasound 1994; 35:110115.

  • 24.

    Stander NWagner WMGoddard A, et al. Normal canine pediatric gastrointestinal ultrasonography. Vet Radiol Ultrasound 2010; 51:7578.

  • 25.

    Agthe PCaine ARPosch B, et al. Ultrasonographic appearance of jejunal lymph nodes in dogs without clinical signs of gastrointestinal disease. Vet Radiol Ultrasound 2009; 50:195200.

    • Crossref
    • Search Google Scholar
    • Export Citation

Advertisement