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C o m p a n i o nThe COMPANION is a publication of Veterinary Specialty &

Emergency Center of Levittown and Philadelphia, PA.

If you would like to receive an electronic version of Companion, please send an email to Rebecca Orsher at rkorsher@vsecvet.com.

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Greetings from Dr. Sandy macLeod

Welcome to the latest issue of our 2013 Companion Newsletter Series, the radiology issue. This issue focuses on diagnostic imaging, a service which has developed and grown substantially at VSEC over the past few years. Almost five years ago, VSEC welcomed me as their first full-time radiologist. I joined forces with Dr. Ana Cáceres to make VSEC the first referral center in the region to offer ultrasound appointments by a board-certified radiologist six days a week, a service and availability that remains valuable and unique to this day. Upon our transition to the new building in Levittown, VSEC’s diagnostic imaging capabilities were improved greatly with the addition of an on-site CT scanner and MRI unit. This past January, with the opening of VSEC-Philadelphia, Dr. Lisa Ziemer was hired as our second full-time board-certified radiologist. With three board-certified radiologists between the two facilities, VSEC is able to offer the highest level of diagnostic imaging service throughout the week, including ultrasound service Monday through Saturday and official, expedient review of all in-house and referral radiographs, MRI and CT studies 24-7. Please do not hesitate to contact us to discuss any case or if you have any questions about diagnostic imaging. We hope you enjoy this issue, which is chock-full of interesting cases and concepts from (what we think is) the fascinating and often perplexing field of veterinary diagnostic imaging.

Warm Regards, Sandy MacLeod, DVM, DACVR

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301 Veterans Highway Levittown, PA 19056215.750.7884

1114 South Front StreetPhiladelphia, PA 19147267.800.1950

Ana V Cáceres BS, DVM, Diplomate ACVR

cystocentesis is a common procedure performed to obtain relatively sterile urine in dogs and cats. The idea behind this procedure is to obtain urine directly from the urinary bladder using a needle to prevent contamination of the urine from the urethra and external genitalia. Although this procedure is usually safe, some severe complications can occur under certain circumstances. Hemoperitoneum and sometimes death can be a complication of blind cystocentesis. To understand how this happens let’s

review the anatomy. The urinary bladder is located in the caudo-ventral abdomen and is the most ventral organ cranial to the pelvic canal. The uterus (if present) and colon are located dorsal to the urinary bladder followed by the distal aorta and caudal vena cava located in the sublumbar area (fig. 1)

Typically a blind cystocentesis is performed with the patient in dorsal recumbence and the needle is introduced from the ventral midline. When the urinary bladder is distended it occupies most of the caudo-ventral abdomen, therefore it is less likely to penetrate other abdominal organs. When the urinary bladder is small, it lays closer to the dorsal structures

such as the aorta, caudal vena cava and external iliac vessels particularly in smaller or thin patients increasing the risk of accidentally penetrating deeper structures (fig.2)

During the past several years we have seen a few cases of intra-abdominal hemorrhage due to accidental puncture of the aorta or external iliac artery during blind cystocentesis. These cases were presented with a history of frank blood obtained from the urinary bladder, hematuria, caudal abdominal pain, signs of shock and hemoperitoneum after cystocentesis. Recently a patient was presented to VSEC with a history of severe hematuria, caudal abdominal mass and pain in the caudal abdomen immediately after a cystocentesis. Given the history and clinical signs arterial puncture and bleeding was suspected and an abdominal ultrasound was performed. The ultrasound showed a heterogeneous hypoechoic mass (fig.3) and free echogenic fluid located dorsal and dorsolateral to the urinary bladder tracking to the dorsally located aorta or external iliac vessels. The structure showed no internal blood flow on color Doppler interrogation. Given the history of cystocentesis, the acute clinical signs and the ultrasonographic findings a diagnosis of intra-abdominal hematoma and hemoperitoneum was suspected.

an unusual but dangerous complication of blind cystocentesis

Figure 1: Anatomy of the canine caudal abdomen. Note the location of the urinary bladder (yellow), colon (purple) and aorta (red).

Figure 2: Lateral abdominal radiograph showing the urinary bladder (yellow), Colon and caudal aorta and external iliac vessels. Note the position of the needle in the pre (a) and post cystocentesis (b).

Continued on page 2

Doctor SpotlightGet to know VSEC specialists

Lisa Ziemer, VmD, DaCVRVSEC Philadelphia RadiologistPicture of Dr. Ziemer

Dr. Lisa Ziemer, VSEC Philadelphia’s board-certified radiologist, graduated from the University of Pennsylvania School of Veterinary Medicine. She then completed a post-doctoral fellowship in the radiation oncology research department of the University of Pennsylvania School of Medicine. After the fellowship, Dr. Ziemer completed a three-year residency in diagnostic imaging at the University of Pennsylvania. Dr. Ziemer is available for outpatient and emergency ultrasound appointments Monday through Friday at VSEC Philadelphia.

outside of veterinary medicine, what do you consider yourself to be an expert at?

…moderately good at? …a total mess at?Expert at: According to Malcolm Gladwell’s essay Outliers, it takes 10,000 hours of practice to become an expert at anything. Using his criteria, I would say sleep is the only thing in my life that truly qualifies. Next in line would have to be music; I have played the flute since I was six and have put in my fair share of practice hours.Moderately good: Working out. I love to run and to lift weights. I’m just not very fast.Total mess: Driving the car and finding clothes that match

What is the last book you read or movie you saw (that you enjoyed) and why

was it enjoyable to you?I recently re-read Slaughterhouse Five by Kurt Vonnegut. I love the use of satire, the commentary on the destructiveness of war, and the idea of being disconnected from time. The narrator leaves us all struggling with the concept of free will. It’s a great read; I may read it again very soon!

What would you be doing today or what would you like to be doing today if you

could not have been a veterinarian? Subatomic particle physicist. I would love to work at CERN’s Large Hadron Collider on the French-Swiss border. I’m really sad I wasn’t there the day they discovered the Higg’s Boson.

What’s on the horizon in your specialty of veterinary medicine that most

excites you?In the near future, I would love to acquire a multi slice CT scanner for our new Philadelphia practice. It would allow us to acquire beautiful CT images in just a matter of seconds- we could do a whole body CT with sedation in almost no time.

In the more distant future, I believe that radiology will be moving away from “anatomic” or “structural” imaging–that is, looking at the size, contour, and architecture of structures- and will be moving towards “functional” imaging. Functional imaging uses various tracers to track different metabolic processes, giving us information such as whether a mass is benign or malignant, how much blood flow it has, what its metabolism is like, what drugs it could respond to, and where the exact borders of the mass may be. I believe a revolution in imaging is coming, where we no longer look at shapes and sizes, but rather look at various functional properties.

What’s the best piece of advice you were ever given, and who gave it to you?When I was a kid, my parents taught me the concept of Occam’s razor (lex parsimoniae), which states that the simplest explanations are generally better than more complex ones. This has proven to be a very useful concept to keep in the back of my mind as we try to work through complicated cases.

cardiology Maribeth J. Bossbaly, VMD, DACVIM (Cardiology)

critical care Laura W. Tseng, DVM, DACVECC Melissa A. Java, VMD, DACVECCGarret E. Pachtinger, VMD, DACVECCRebecca S. Syring, DVM, DACVECC

dermatologyIan B. Spiegel, VMD, MHS, DACVDJacqueline B. Watson, DVMdiagnostic imaging Alexander G. MacLeod, DVM, DACVR Ana V. Cáceres, DVM, DACVRLisa S. Ziemer, VMD, DACVR

emergency medicine Kevin J. Attermeier, DVMLaura E. Babcock, DVMCaleb S. Frankel, VMDStephanie N. Harrier, DVMKaren L. Palazzini, DVMLaura Roy-Eitner, DVM

Rosanna Scali, DVM Laura K. Schmitt, VMDLaura G. Tasker, DVM holistic medicine & acupuncture Kendra V. Pope, DVM, CVA, CVCH, CVFT, CVTP

internal medicine Alan R. Klag, DVM, DACVIM Peter S. Chapman, BVetMed (Hons), DECVIM-CA, DACVIM, MRCVSCara R. Horowitz, DVM, DACVIMJamie Lewis Etish, VMD, ResidentMarie E. Buckley, VMD, Resident

Continued from page 1

Dr. Lisa Ziemer

an unusual but dangerous complication of blind cystocentesis

Ultrasonography is a noninvasive, highly skill dependent diagnostic tool use to evaluate soft tissue structures, mainly intra-cavitary structures such as the heart and abdominal organs. Cystocentesis is a safe procedure when perform with caution keeping in mind the complications. Ultrasound is a useful tool to perform cystocentesis because the path of the needle entering the abdomen and urinary bladder is always seen, therefore avoiding the penetration of other structures, particularly the caudal abdominal vessels and colon. Another advantage of the use of ultrasound in complicated cases is that the presence of a mass, stones and urinary bladder wall abnormalities can be easily recognized by a skilled ultrasonographer. The puncture of a bladder mass during cystocentesis is not recommended due to the risk of seeding tumor cells in the abdomen from the needle path. Patients with urinary bladder wall disease such as emphysematous cystitis seen in diabetic patients and severely distended bladder from lower urinary tract obstruction are at high risk for bladder rupture resulting in uroperitoneum from cystocentesis, therefore it should be avoid in these patients.

Understanding the risks and identifying the higher risk patients are ways to prevent an unfortunate complication from this procedure. Ways to prevent puncturing a near vessel is to perform cystocentesis using the lateral approach holding the urinary bladder with one hand or using ultrasound guidance in patients with small urinary bladder, small, thin or large/obese patients or when the urinary bladder cannot be palpated.

Figure 3. Ultrasound image at the level of the urinary bladder. Note the urinary bladder seen as a small hypoechoic structure displaced to the right of the image by a heterogeneous hypoechoic structure (between the cursors). The structure was a peritoneal hematoma secondary to puncture of the left iliac artery during blind cystocentesis.

Kristi Simone, MB, VMD, Diagnostic Imaging Intern

a 2 year old female spayed indoor-only Himalayan was evaluated for increased respiratory effort which was accentuated following exercise. The cat maintained a normal attitude and appetite and no coughing or collapse episodes had been observed by the owners. On physical examination, mild tachypnea was noted and the heart sounds were mildly muffled bilaterally on auscultation. Radiographs of the thorax were obtained for further evaluation. See Figure 1.

The cardiac silhouette is enlarged and has irregular, rounded margins. The caudal border of the cardiac silhouette and the cranioventral diaphragmatic border are adjacent to each other and their borders are not clearly distinguishable. A subtle heterogenous radiopacity is superimposed over the cardiac silhouette. The pulmonary vessels and pulmonary parenchyma are normal. (Incidentally,

What’s Your Diagnosis?

Figure 1 – Right lateral (A) and dorsoventral (B) radiographs of the thorax of a 2-year-old spayed female Himalayan with tachypnea and muffled heart sounds bilaterally.

neurology/neurosurgery Joseph S. Eagleson, DVM, DACVIM (Neurology)

oncology Kathy J. Kazmierski, VMD, MS, DACVIM (Oncology)Rebecca E. Risbon, VMD, DACVIM (Oncology)Siobhan M. Haney, VMD, MS, DACVR (RO)Consultant in Radiation Oncology

ophthalmology Jerome M. Glickstein, VMD

surgeryRobert J. Orsher, VMD, DACVS Catherine A. Popovitch, DVM, DACVS, DECVS Ron Ben-Amotz, DVM, MS, DACVS, DECVSJennifer S. MacLeod, VMD, DACVS Kimberly A. Agnello, DVM, MS, DACVS, Consultant Melissa M. Hobday, VMD

Michelle C. Trappler, VMD, ResidentGeoffrey M. Harriman, DVM, ResidentMicha C. Simons, VMD, ResidentWilliam L. Snell, DVM, ResidentSarah E. Round, DVM, Resident

Using multiple, “Snazzy” imaging tests to diagnose a perplexing lameness

“snazzy” is an 11 year old, male castrated Jack Russell Terrier who presented for lameness of the left front limb. Multiple diagnostics and treatments had been attempted, including radiographs, acupuncture, laser therapy and NSAID therapy. The patient had even been to another referral center in the area where he had a shoulder ultrasound and received steroid injections of the shoulder joint. Despite this thorough workup and multiple treatments, the lameness was progressing to the point of complete non-weightbearing. An MRI of the neck and axillary region was recommended. MRI of the neck revealed no major abnormalities (see Figure 1). The intervertebral disc at C6-7 was hypointense (consistent with dessication) and protruded mildly into the vertebral canal (see arrow), but this did not cause significant spinal cord or spinal nerve compression to account for the lameness.

Further imaging of the shoulder and axillary region was recommended. This revealed a tubular abnormal soft tissue structure in the region of the left brachial plexus (see arrow, Figure 2).

As this lesion was not palpable, an ultrasound of the axilla was performed to confirm a suspected nerve-based mass.

These imaging findings supported a diagnosis of a peripheral nerve sheath tumor of the brachial plexus. Peripheral nerve sheath tumors are a category of tumor that includes neurofibromas, schwannnomas and other classifications. Dogs with this condition present

with unilateral thoracic limb lameness, muscle atrophy and pain. When these tumors grow large enough they may be palpable upon deep palpation of

the axilla. This particular tumor could not be felt even once diagnosed. Radiography is poorly sensitive for detecting brachial plexus tumors, but contrast-enhanced CT, MRI and ultrasound have proven essential to make this diagnosis. In this case, we used ultrasound to confirm a lesion identified on MRI. Ultrasound can also be used as a screening tool for this disease in patients with the appropriate clinical signs. However, ultrasound cannot always image the full extent of the lesion, particularly if it advances into the vertebral canal and spinal cord. Therefore, a combination of imaging modalities such as ultrasound and MRI is often necessary to fully define the extent of the disease process.

The diagnosis in this case was challenging and was only made due to a collaborative effort between different specialists and prudent employment of synergetic diagnostic imaging capabilities. Our goal at VSEC is to work together as an efficient team to make an accurate diagnosis, determine the best treatment options and prognosis for our patients, and effectively communicate our findings and recommendations to the client and referring veterinarian. With the opening of our Philadelphia practice, this philosophy is now in effect between two major referral centers in the region, and the resources and staff of both practices work together to maintain the highest standard of veterinary care.

Reference:Rose S, Long C, Knipe M, Hornof B. Ultrasonographic evaluation of brachial plexus tumors in five dogs. Veterinary Radiology and Ultrasound, Vol 46, No. 6, 2005, pp 514-517.

Alexander G. MacLeod, DVM, DACVR

Figure 1. Sagittal T2 image of the cervical vertebral column and spinal cord. Cranial is to the left, dorsal is toward the top. The arrow is pointing at a dessicated, mildly protruding intervertebral disc at C6-7.

Figure 2. Coronal proton-density MR image of the brachial plexus region. There is an asymmetric hyperintense tubular structure on the left (arrow).

Figure 3. Doppler ultrasound of the left axillary region. There is a hypoechoic tubular shaped mass lesion in the region of the axillary nerve. Doppler ultrasound was used to document the absence of blood flow in this structure, as it could be confused for a blood vessel.

L1 is a transitional veterbra with 2 extra ribs.) On the basis of these findings, a peritoneopericardial diaphragmatic hernia (PPDH) was suspected. Differential diagnoses considered much less likely were pericardial effusion and/or cardiomegly. See Figure 2.

Echocardiography confirmed the presence of a portion of the liver within the pericardial space. See Figure 3. Heart chamber size and wall thickness were found to be within reference range. An abdominal exploratory surgery revealed a communication between the peritoneal cavity and the pericardial sac; the right medial liver lobe was herniated into the pericardial sac as was a portion of falciform fat. The falciform fat was resected and the liver lobe was replaced within the abdomen. The edges of the diaphragmatic defect were debrided and sutured in a simple continuous pattern. The cat recovered uneventfully from surgery.

A diagnosis of PPDH is made when abdominal viscera herniates into the pericardial sac though a congenital hiatus. PPDH is the most common congenital

Figure 2 – Same radiographs as in Figure 1. Notice that the caudal border of the cardiac silhouette is indistinguishable from the cranioventral diaphragm (white arrows). There are inhomegenous radiopacities in the region of the cardiac silhouette (black arrows) which are more clearly visible on the lateral radiograph.

diaphragmatic defect in the dog and cat and is attributed to a faulty development of the tendinous ventral portion of the diaphragm. More than one theory for how this occurs has been proposed: 1. the septum transversum (the embryologic structure that forms the ventral portion of the diaphragm) fails to close, or 2. the septum transversum fails to fuse with the pleuroperitoneal folds (the embryologic structures that

form the dorsolateral portion of the diaphragm) (Evans, 1980). This malformation creates an abnormal communication between the peritoneum and pericardial sac. PPDH has been reported to occur in littermates and affected animals may have other congenital abnormalities including sternal anomalies (i.e. pectus excavatum, absent sternebra) and heart murmurs. Breed predilection has been documented and includes Weimaraners, domestic longhair cats, and Himalayans.

In the dog and cat, the most commonly herniated organs are the liver and gallbladder followed by the small intestine, spleen, stomach, and occasionally mesentery, omentum, and falciform ligament (Reimer, 2004). Passage of these organs into the pericardial sac may result in compromised function of the respiratory tract, gastrointestinal tract obstruction, gallbladder torsion, splenic or hepatic entrapment, and occasionally cardiac tamponade.

Although PPDH is typically diagnosed in young animals, it can be found in dogs and cats of any age. Clinical signs are highly variable and range from completely asymptomatic to sudden death (attributable to cardiac tamponade). A PPDH should be considered as a differential diagnosis in animals of any age that are presented

Figure 3 – Echocardiography revealed liver (white arrow) within the pericardial sac immediately adjacent to the heart (black arrow).

Continued on page 4

301 Veterans HighwayLevittown, PA 19056215.750.7884

www.vsecvet.com

if you would like to receive an electronic version of Companion, please send an email to rebecca orsher at rkorsher@vsecvet.com.

Please RSVP to: rkorsher@vsecvet.com or 215.809.2656

Upcoming VSEC Continuing Education Lectures Vsec philadelphia lecture seriesLectures will be held at Mekong River – 1120 South Front Street, Philadelphia, PA 19147

VETERINARIAN LECTURE Wednesday, May 22, 6:30pm-9pmWound Management: Should you Vac it or Wrap It?Hip Dysplasia: Diagnosis, Evaluation, Treatment Planning and Postoperative Management

Vsec leVittoWn lecture seriesLectures will be held at VSEC: 301 Veterans Hwy, Levittown, PA 19056

TECHNICIAN LECTUREMonday, June 3, 7pm-9pmAnesthetic Monitoring of the Surgical Patient: Stayin’ Alive, Stayin’ Alive!Sarah Round, DVM, Surgery ResidentAmy Meenan, CVT, Assistant Nurse Manager – Surgery.

These programs have been submitted (but not yet approved) for 2.0 hours of continuing education credit in jurisdictions which recognize AAVSB RACE approval; however participants should be aware that some boards have limitations on the number of hours accepted in certain categories and/or restrictions on certain methods of delivery of continuing education. Call Rebecca Orsher at 215-750-7884 for further information. All lectures are given in a classroom setting and no registration fee is required. VSEC RACE Provider #513.

with a chronic history of moderate to severe cardio or respiratory distress with or without gastrointestinal tract dysfunction when there is no evidence or history of pervious trauma. Diagnosis is typically made on radiographs; findings indicative of PPDH may include a large, rounded cardiac silhouette, abdominal organs identified in the pericardial sac (presence of gas, ingesta, or structures of soft tissue opacity), and an indistinguishable border of the ventral thoracic diaphragmatic surface and the caudoventral cardiac silhouette (Thrall, 2013). In cases where PPDH is suspected, a thoracic ultrasound should be considered for further assessment. Animals with overt clinical signs attributable to PPDH are candidates for surgical intervention. Animals that are asymptomatic do not necessarily require treatment.

refrences:Burns, CG, MS Bergh, MA McLoughlin. Surgical and nonsurgical treatment of

peritoneopericardial diaphragmatic hernia in dogs and cats: 58 cases (1999-2008). JAVMA, Vol 242, No 5., March 2013.

Evans, SM, DN Biery. Congenital Peritoneopericardial Diaphragmatic Hernia in the Dog and Cat: A Literature Review and 17 additional case histories. Veterinary Radiology, Vol 21, No 3, 1980: p108-116.

Reimer, SB, AE Kyles, DE Filipowicz, CR Gregory. Long-term outcome of cats treated conservatively or surgically for peritoneopericardial diaphragmatic hernia: 66 cases (1987-2002). JAVMA, Vol 224, No 5, March 2004.

Thrall, Donald E., Textbook of Veterinary Diagnostic Radiology, 6th Edition. Saunders, 2013.

What’s Your Diagnosis? Continued from page 3