A Computed Tomographic Study of the Molar Teeth of Babyrousa spp.

A photographic and computed tomography (CT) scanning study was carried out on 295 molar teeth of 18 adult male Babyrousa babyrussa skulls and 8 skulls of Babyrousa celebensis including seven adult males and one adult female. The occlusal morphology of the permanent maxillary and mandibular molar teeth of B. babyrussa was very similar to that of B. celebensis. Most B. babyrussa maxillary molar teeth had six roots, with small numbers of teeth having four, five or seven roots. A similar pattern was suggested in B. celebensis. Mandibular molar teeth had between four and eight roots. Tooth roots of maxillary and mandibular first and second molar teeth were largely tapering, rod-like structures. The roots of the right and left maxillary third molar teeth had a more complex arrangement; some were inserted almost vertically into the maxilla; others were orientated in a more distal direction. The mesial and distal roots were splayed in appearance. The right and left mandibular third molar tooth roots retained elements of the open 'C' shape and were generally orientated distally. The pulp chambers were arched to fit under the main cusps in all molar teeth. Pulp canals were variable in number.

The Role of Femoral Head Size and Femoral Head Coverage in Dogs with and without Hip Dysplasia.

The subject of hip dysplasia in dogs is still current and preoccupies both animal owners and veterinarians. Major factors affecting the development of the disorder are hip laxity and incongruent joints. Many studies on etiology, pathogenesis, and early diagnosis have been performed to reduce prevalence and select healthy dogs for breeding. The purpose of the present study was to investigate a possible relationship between dysplasia and femoral head area (FHA), femoral coverage by the acetabulum (CFH) and cranio-caudal distance of the dorsal acetabular rim (CrCdAR). Radiographs of a total of 264 skeletally mature dogs with similar physical characteristics (German wirehaired pointers (GWP), German shepherd dogs (GSD) and Labrador retrievers (LAB)) presented for routine hip dysplasia screening were recruited for the study. FHA, CFH and CrCdAR were measured and related to dysplasia status. Evaluations of FHA (p = 0.011), CFH (p < 0.001) and CrCdAR length (p = 0.003) measurements revealed significant interactions between breed, sex and FCI scores, so they had to be assessed separately. The results revealed that FHA tends to decrease as the hip dysplasia score worsens. There was no significant relationship between FHA and dysplasia assessment. FHA is breed-specific and is larger in normal and near-normal male (p = 0.001, p = 0.020) and female (p = 0.001, p = 0.013) GWP compared to GSD, respectively. FHA is greater in normal male GWP (p = 0.011) and GSD (p = 0.040) compared to females. There was a significant and strong positive correlation between FHA and CrCdAR in all breeds and sexes. Additionally, FCI scoring had a medium (GWP, GSD) to strong (LAB) negative correlation with CFH.

[Long-term examinations of the lumbal disc and facet joint changes in 5 German Shepard dogs]. / Verlaufsuntersuchung der lumbalen Bandscheiben- und Facettengelenkveränderungen bei 5 Deutschen Schäferhunden.

OBJECT AND PURPOSE: The purpose of this first-time long-term observational study was to evaluate the changes of the caudal lumbar spine at the locations L5/6, L6/7, and L7/S1 in 5 German shepherd dogs over a 6-year time period using computed tomography (CT) and magnetic resonance imaging (MRI). The dogs had a mean age of 26 months at the time of the first examination. In addition, it was evaluated whether a breeding examination, with regard to disc degeneration, is justified in young dog. MATERIAL AND METHODS: The locations L7/S1, L6/7, and L5/6 were examined in more detail with regard to their signal intensity changes, the facet joint angle changes in dorsal (dors) and transverse (trans) planes, and disc surface changes in sagittal (sag) and transverse (trans) reconstruction planes with CT and MRT in 2015 and 2021. All data were collected computer-based and analyzed statistically. Subsequently, the results were compared to the measured signal intensity and to the subjective disc degeneration grading according to Seiler used in practice. RESULTS: Over the period of 6 years a significant loss of the measured signal intensity of the intervertebral discs in the transverse plane and an overall facet joint widening in the transverse plane of 0.54° as well as in the dorsal plane of 1.8° was evident. In addition, there was no evidence of a relationship between the size of the facet joint angle and the degree of disc degeneration. Furthermore, regardless of the initial degree of degeneration, the discs showed low signal intensity and higher Seiler grade during follow-up. CONCLUSION AND CLINICAL RELEVANCE: The results of the present study group indicate that an inconspicuous condition of the lumbar intervertebral discs at the time of the initial breeding examination in the young dog does not allow an accurate prediction of the subsequent degree of degeneration and that there are ongoing remodeling processes at the facet joints even in healthy German shepherd dogs.

Video Endoscopy-Guided Intrabronchial Spray Inoculation of Mycobacterium bovis in Goats and Comparative Assessment of Lung Lesions With Various Imaging Methods.

Bovine tuberculosis (bTB) not only poses a zoonotic threat to humans but also has a significant economic impact on livestock production in many areas of the world. Effective vaccines for humans, livestock, and wildlife are highly desirable to control tuberculosis. Suitable large animal models are indispensable for meaningful assessment of vaccine candidates. Here, we describe the refinement of an animal model for bTB in goats. Intrabronchial inoculation procedure via video-guided endoscopy in anesthetized animals, collection of lungs after intratracheal fixation in situ, and imaging of lungs by computed tomography (CT) were established in three goats using barium sulfate as surrogate inoculum. For subsequent infection experiments, four goats were infected with 4.7 × 102 colony-forming units of M. bovis by intrabronchial inoculation using video-guided endoscopy with spray catheters. Defined amounts of inoculum were deposited at five sites per lung. Four age-matched goats were mock-inoculated. None of the goats developed clinical signs until they were euthanized 5 months post infection, but simultaneous skin testing confirmed bTB infection in all goats inoculated with M. bovis. In tissues collected at necropsy, M. bovis was consistently re-isolated from granulomas in lymph nodes, draining the lungs of all the goats infected with M. bovis. Further dissemination was observed in one goat only. Pulmonary lesions were quantified by CT and digital 2D radiography (DR). CT revealed mineralized lesions in all the infected goats ranging from <5 mm to >10 mm in diameter. Small lesions <5 mm predominated. The DR failed to detect small lesions and to determine the exact location of lesions because of overlapping of pulmonary lobes. Relative volume of pulmonary lesions was low in three but high in one goat that also had extensive cavitation. CT lesions could be correlated to gross pathologic findings and histologic granuloma types in representative pulmonary lobes. In conclusion, video-guided intrabronchial inoculation with spray catheters, mimicking the natural way of infection, resulted in pulmonary infection of goats with M. bovis. CT, but not DR, presented as a highly sensitive method to quantify the extent of pulmonary lesions. This goat model of TB may serve as a model for testing TB vaccine efficacy.

Computed Tomography Enhances Diagnostic Accuracy in Challenging Medial Coronoid Disease Cases: An Imaging Study in Dog Breeding Appeal Cases.

OBJECTIVES: The aim of this study was to determine the radiographic sensitivity in detecting medial coronoid disease (MCD), using computed tomography (CT) as reference in dogs presented for an official second opinion, and to compare the medial coronoid process (MCP) in fragmented and fissured MCP as well as those unaffected by MCD. MATERIALS AND METHODS: The data of dogs, presented for official second opinion radiographs and CT, were reviewed by three board-certified observers and in accordance with the International Elbow Working Group guidelines regarding MCD. Radiographic delineation, radiopacity and Hounsfield Units (HU) of the MCP were recorded additionally and the correlation between radiography and CT was investigated. RESULTS: Sensitivity and specificity of radiography compared with CT yielded values of 83.6% for the former and 83.5% for the latter. False-negative grading in radiography correlated significantly (p = 0.0001) with a present fissure line in CT. The mean delineation (p = 0.03) and mean HU of fragmented MCP (p = 0.0045) were significantly reduced compared with fissured MCP and no significant differences in measured HU for fissured MCP were detected in comparison to elbows unaffected by MCD. CONCLUSION: The results of the present study show substantial agreement between radiography and CT in second opinion cases. However, sensitivity is reduced compared with not preselected cases. A present fissure line in CT was significantly associated with a false-negative grading in radiography. Therefore, CT imaging of the elbows is strongly recommended in cases of appeal.

[Computed tomography based elbow joint morphology and incidence of elbow dysplasia in the red fox (Vulpes vulpes)]. / Computertomografische Morphologie des Ellbogengelenks und Vorkommen der Ellbogengelenkdysplasie beim Rotfuchs (Vulpes vulpes).

OBJECTIVE: Elbow dysplasia (ED) is a common developmental disease of the canine elbow joint and one of the most frequent causes of forelimb lameness in domestic dogs (Canis lupus familiaris). ED is predominantly present in medium to large breed dogs, but has also been described in mixed breed dogs and smaller breeds. In the literature, no information is available concerning the existence of ED in wildlife species. The purpose of the present study was to obtain an overview of the elbow joint anatomy of the red fox as well as to demonstrate the incidence of ED in red foxes. Knowledge regarding the elbow conformation in red foxes may help to understand the effect of anatomical difference onto the pathogenesis of developmental elbow disease. MATERIAL AND METHODS: A total 94 elbow joints of 49 red foxes (Vulpes vulpes) were evaluated using computed tomography (CT) and were compared to canine elbow joints. RESULTS: Apart from size differences and minor species-specific variations, the anatomy of the elbow joints of red foxes and domestic dogs proved to be very similar. In the red foxes, the rounded conformation of the medial coronoid process was shown to be present in 76 % of the individuals. Two elbow joints in 2 red foxes exhibited pathological changes of the medial coronoid process in the CT imaging. CONCLUSION: The prevalence of medial coronoid disease in red foxes amounted to 2.1 % in the presented population. This observation is comparable to the prevalence of elbow dysplasia in small breed dogs. The rounded conformation of the medial coronoid process was found in more than three-quarters of the examined red foxes. This leads to the hypothesis that this conformation of the medial coronoid process could be the original, physiological variant. Selective breeding for such a morphological feature may be an approach to reduce the frequency of canine elbow dysplasia. CLINICAL RELEVANCE: The significance of anatomical characteristics in the development of elbow dysplasia is still unknown. Therefore, research concerning the pathogenesis of medial coronoid disease should set its focus not only on elbow joint anatomy, but also on other influencing factors, such as biomechanics, genetics and environmental parameters.

Improved Computed Tomography Accuracy with a 1-mm versus 2- or 3-mm Slice Thickness for the Detection of Medial Coronoid Disease in Dogs.

OBJECTIVE: Computed tomography (CT) is used complementarily to radiography for the evaluation of medial coronoid disease (MCD). We hypothesized that a slice thickness > 2 mm would significantly affect the image quality and detection of fragmentation of the medial coronoid process. This study aimed to assess CT features indicating direct and indirect evidence of MCD in 168 CT studies with slice thicknesses of 1-, 2- and 3 mm. MATERIALS AND METHODS: The CT studies were blinded in terms of CT slice thickness and patient data and randomly assessed by two independent observers. All dogs underwent arthroscopic evaluation of the elbow joints. Both observers were unaware of the arthroscopic findings. RESULTS: Notably, blurring of the bone contour (p = 0.0001) was significantly influenced by slice thickness; here, a 1-mm thickness yielded a predominantly sharp and well-defined bone contour (observer 1, 91%; observer 2, 79%), whereas 2- (observer 1, 39.3%; observer 2, 56.3%) and especially 3-mm slice thicknesses yielded blurred margins with significantly reduced sharpness (observer 1, 0%; observer 2, 12.5%). The 1-mm slice thickness also yielded the highest fragment detection rate (observer 1, 55.4%; observer 2, 60.4%). Furthermore, the detection of fragment positions and of single fragments and fissures differed substantially with slice thickness. CLINICAL RELEVANCE: The findings of this study support the hypothesis that a CT slice thickness of ≥ 2 mm significantly affects fragment detection. In conclusion, a CT slice thickness of at least 1 mm is recommended for the assessment of MCD of the canine elbow.

[Ultrasonography of the lower urethra in male sheep lambs]. / Sonographische Darstellung der distalen Harnröhre beim männlichen Schaflamm.

In male small ruminants, voiding disturbances are not uncommon. A precise knowledge of the underlying disease is essential for prognostic evaluation as well as for a decision concerning the therapeutic approach. Common reasons for voiding disturbances in the male small ruminant are obstructive urolithiasis, traumata of the penis or inflammatory processes within the urethra or urinary bladder. The diagnostic method of choice - in addition to clinical examination - is diagnostic imaging. Because radiology is not always possible under field conditions, the aim of this article is a detailed presentation of ultrasonography of the distal urethra of the male lamb.

Magnetic Resonance Imaging Assessment of Intra-Articular Structures in the Canine Stifle Joint after Implantation of a Titanium Tibial Plateau Levelling Osteotomy Plate.

OBJECTIVES: To determine the effectiveness of magnetic resonance imaging (MRI) in the evaluation of anatomical stifle structures with respect to implant positioning after tibial plateau levelling osteotomy (TPLO) using a titanium plate. METHODS: Selected sagittal and dorsal sequences of pre- and postoperative MRI (1.0 T scanner) of 13 paired (n = 26) sound cadaveric stifle joints were evaluated. The effect of susceptibility artifact on adjacent anatomical stifle structures was graded from 0 to 5. The impact of implant positioning regarding assessment score was calculated using Spearman's rank correlation coefficient. RESULTS: Sagittal turbo spin echo (TSE)-acquired images enabled interpretation of most soft tissue, osseous and cartilage structures without detrimental effect of susceptibility artifact distortions. In T2-weighted TSE images, the cranial cruciate ligament and caudal horn of the medial meniscus could be evaluated, independent of implant position, without any susceptibility artifact in all specimens. T2-weighted fast field echo, water selective, balanced fast field echo and short tau inversion recovery were most markedly affected by susceptibility artifact. CLINICAL SIGNIFICANCE: In selected TSE sequences, MRI allows evaluation of critical intra-articular structures after titanium TPLO plate implantation. Further investigations with confirmed stifle pathologies in dogs are required, to evaluate the accuracy of MRI after TPLO in clinical cases in this context.

Measurement of the normal feline pituitary gland in brachycephalic and mesocephalic cats.

Objectives The purpose of this study was to determine differences in normal feline pituitary dimensions in brachycephalic and mesocephalic cats as a basis for establishing cryohypophysectomy in cats. Methods Measurements were performed on sagittal T2-weighted and transverse post-gadolinium T1-weighted or T1 3D fast field echo-weighted MRI images. A total of 32 brachycephalic and 27 mesocephalic cats were examined. Inter-observer reproducibility was assessed by t-test and Bland-Altman analysis. Results The cats were 0.6-15.9 years of age with a body weight range of 1.84-6.60 kg. For brachycephalic cats, the mean pituitary gland sagittal height was 2.15 ± 0.15 mm, pituitary gland transverse height was 2.42 ± 0.21 mm, pituitary gland transverse width was 4.44 ± 0.27 mm and pituitary gland sagittal length was 3.14 ± 0.30 mm. In mesocephalic cats, the pituitary gland dimensions were 2.94 ± 0.16 mm, 3.09 ± 0.26 mm, 4.73 ± 0.31 mm and 4.88 ± 0.30 mm for pituitary gland sagittal height, transverse height, transverse width and sagittal length, respectively. There was a highly significant correlation between brachycephalic and mesocephalic cats and pituitary gland height and length ( P <0.0001), respectively. Sex also had an effect on pituitary gland measurements. Neutering status had no significant effect on hypophyseal measurements. Age had a significant influence on pituitary gland height, width and length in the brachycephalic population. Inter-observer reproducibility was good to excellent. Conclusions and relevance The different pituitary measurements in brachycephalic and mesocephalic cats has to be considered if surgery comes into question. There are ranges in pituitary gland sizes, even among the mesocephalic cat population. Thus, exact measuring of the pituitary gland is crucial before any surgical intervention.

Correlation between Preoperative Ultrasonographic Findings and Clinical, Intraoperative, Cytopathological, and Histopathological Diagnosis of Acute Abdomen Syndrome in 50 Dogs and Cats.

Acute abdomen syndrome is an emergency in small animal practice that requires rapid diagnosis to determine the appropriate treatment. No studies have correlated the preoperative abdominal ultrasonography (US) findings with the clinical, surgical, cytopathologic, and histopathologic findings. This retrospective study was designed to evaluate abdominal US in the diagnosis of acute abdomen syndrome using surgery as a "criterion standard". The most frequently misinterpreted lesions with US were also identified. The study included 50 dogs and cats with physical examination, an US diagnosis, US guided fine-needle aspiration cytology, intraoperative findings, and histopathology. Intraoperatively, 49 primary and 43 secondary lesions were identified. The sensitivity, specificity, and positive and negative predictive values for US were calculated. There was a good agreement between the US diagnosis and intraoperative findings of 86.9% (80/92), for both primary and secondary lesions (p < 0.0001). Cytology and histopathology examinations corroborated the US in 86.4% (n = 64/74) of primary and 66.2% of secondary (n = 49/79) lesions. Using US as the "criterion standard", the sensitivity of abdominal palpation for identification of ascites and masses was 32.4% and 43.7%, respectively, while the specificity was 93.7% and 94.4%, respectively. Abdominal US is a useful preoperative modality for diagnosing acute abdominal diseases in dogs and cats. Care should be taken with interpretation of gastrointestinal perforation, omental tumors, and common bile duct rupture, as these lesions are frequently misinterpreted with US.

Sonography of the distal urethra in lambs.

Sonography is a convenient, non-invasive diagnostic modality in small ruminants, often used in reproductive management, internal medicine, and surgery. Pregnancy diagnostics and imaging anatomy and pathology of organs, such as neoplasia, are major applications. Urolithiasis is one of the most common causes of death in male sheep and goats, for which sonography is the diagnostic modality of choice. Although ultrasound-imaging techniques for kidneys, ureters, and urinary bladder in small ruminants have been described previously, this study focuses on reporting the imaging technique of the extra-pelvic portion of the urethra, as nearly all the cases of obstructive urolithiasis result from urinary stones in this part. Thirty-three Lacaune-crossbred lambs were examined using a 12 MHz linear probe in laterally recumbent animals. Using this technique, the urethral lumen could be visualised through its entire course in all lambs.

[Nasopharyngeal cyst of the respiratory epithelium in a 9-year-old Yorkshire terrier]. / Nasopharyngeale Zyste des respiratorischen Epithels bei einem 9 Jahre alten Yorkshire Terrier.

In a 9-year-old Yorkshire terrier a cyst of the respiratory epithelium of the nasopharynx was diagnosed. A complete obstruction of the nasopharynx leading to dyspnea was detected by computed tomography and endoscopy. A minimally invasive ablation of the cystic wall was performed under endoscopic guidance, followed by a pathohistological examination. Immediately after resection of the cyst, the clinical symptoms resolved. The follow-up endoscopical examination 3 months postoperatively was unremarkable. In the presented case the minimally invasive endoscopic ablation of the cystic wall was a successful treatment method.

[Spinal nephroblastoma at an uncommon localization in a dog]. / Spinales Nephroblastom in ungewöhnlicher Lokalisation bei einem Hund.

A 7-month-old intact male Otterhound was presented for diagnosis of progressive hindlimb paresis. The neurological examination revealed a severe ambulatory paraparesis localised to the left-sided region of the lower motor neuron (L4-S1). Magnetic resonance imaging was suggestive for an intradural-extramedullary neoplasia at the fifth lumbar vertebra. Surgical exploration demonstrated an intradural-extramedullary mass, which partially invaded the spinal cord. The mass was removed with the exception of the intramedullar part, and the diagnosis of a nephroblastoma was made histopathologically. Following radiation therapy, the dog fully recovered and displayed no signs of neurological dysfunction 9 months after surgery.

Behaviour of adipose-derived canine mesenchymal stem cells after superparamagnetic iron oxide nanoparticles labelling for magnetic resonance imaging.

BACKGROUND: Therapy with mesenchymal stem cells (MSCs) has been reported to provide beneficial effects in the treatment of neurological and orthopaedic disorders in dogs. The exact mechanism of action is poorly understood. Magnetic resonance imaging (MRI) gives the opportunity to observe MSCs after clinical administration. To visualise MSCs with the help of MRI, labelling with an MRI contrast agent is necessary. However, it must be clarified whether there is any negative influence on cell function and viability after labelling prior to clinical administration. RESULTS: For the purpose of the study, seven samples with canine adipose-derived stem cells were incubated with superparamagnetic iron oxide nanoparticles (SPIO: 319.2 µg/mL Fe) for 24 h. The internalisation of the iron particles occurred via endocytosis. SPIO particles were localized as free clusters in the cytoplasm or within lysosomes depending on the time of investigation. The efficiency of the labelling was investigated using Prussian blue staining and MACS assay. After 3 weeks the percentage of SPIO labelled canine stem cells decreased. Phalloidin staining showed no negative effect on the cytoskeleton. Labelled cells underwent osteogenic and adipogenic differentiation. Chondrogenic differentiation occurred to a lesser extent compared with a control sample. MTT-Test and wound healing assay showed no influence of labelling on the proliferation. The duration of SPIO labelling was assessed using a 1 Tesla clinical MRI scanner and T2 weighted turbo spin echo and T2 weighted gradient echo MRI sequences 1, 2 and 3 weeks after labelling. The hypointensity caused by SPIO lasted for 3 weeks in both sequences. CONCLUSIONS: An Endorem labelling concentration of 319.2 µg/mL Fe (448 µg/mL SPIO) had no adverse effects on the viability of canine ASCs. Therefore, this contrast agent could be used as a model for iron oxide labelling agents. However, the tracking ability in vivo has to be evaluated in further studies.

Magnetic resonance imaging and clinical findings in carbon monoxide intoxication in dogs. A case series. / Magnetresonanztomographische und klinische Befunde von drei Hunden nach Kohlenmonoxidvergiftung. Eine Fallserie.

This paper presents magnetic resonance imaging (MRI) findings of three dogs after carbon monoxide intoxication. In the first and second cases, MRI changes were confined to both caudate nuclei and in the first case also to the putamen as bilaterally symmetric diffuse homogenous T2 and FLAIR hyperintense, T1 hypointense lesions. No contrast enhancement was seen. In the third case MRI revealed multiple areas of hyperintensity bilaterally on T2 and FLAIR as well as ill-defined areas within the frontal, parietal and occipital grey matter. The caudal colliculi, globus pallidus, substantia nigra and central area of the thalamus showed bilaterally hyperintense lesions on T2w and FLAIR with moderate enhancement after intravenous contrast administration.

Clinical, radiographic, and magnetic resonance imaging findings of gastrocnemius musculotendinopathy in various dog breeds.

OBJECTIVES: To describe clinical, radiographic, and magnetic resonance imaging (MRI) findings in 16 dogs diagnosed with gastrocnemius musculotendinopathy. METHODS: Retrospective evaluation of medical records, radiographs, and MRI results, as well as follow-up completed by telephone questionnaire. RESULTS: Most dogs had chronic hindlimb lameness with no history of trauma or athletic activities. Clinical examination revealed signs of pain on palpation without stifle joint instability. Seven dogs had radiographic signs of osteophyte formation on the lateral fabella. Magnetic resonance imaging revealed T2 hyperintensity and uptake of contrast agent in the region of the origin of the gastrocnemius muscle. Changes were found in the lateral and medial heads of the gastrocnemius. Conservative treatment resulted in return to full function in 11 dogs. Two dogs showed partial restoration of normal function, one dog showed no improvement. Two dogs were lost to follow-up. CLINICAL SIGNIFICANCE: Gastrocnemius musculotendinopathy is a potential cause of chronic hindlimb lameness in medium to large breed dogs. A history of athletic activity must not necessarily be present. Magnetic resonance imaging shows signal changes and uptake of contrast agent in the region of the origin of the gastrocnemius muscle. A combination of T1 pre- and post-contrast administration and T2 weighted sequences completed by a fat-suppressed sequence in the sagittal plane are well-suited for diagnosis. Conservative treatment generally results in return to normal function.

Magnetic resonance imaging features of esthesioneuroblastoma in three dogs and one cat.

OBJECTIVE: Esthesioneuroblastoma is a rare malignant intranasal tumor that originates from the olfactory neuroepithelium of the upper nasal cavity, and can destroy the cribriform plate and expand into the neurocranium. Descriptions of the magnetic resonance features of esthesioneuroblastomas in animals are scarce. The objectives of this study were to report the magnetic resonance imaging features of esthesioneuroblastomas in order to determine distinct imaging characteristics that may help distinguish it from other intracranial tumor types. MATERIAL AND METHODS: Magnetic resonance images of four patients with confirmed esthesioneuroblastomas were reviewed and compared with previously reported cases. RESULTS: The esthesioneuroblastomas appeared as oval-shaped, solitary lesions in the caudal nasal cavity that caused osteolysis of the cribriform plate and extended into the brain in all cases. Signal intensity was variable. Contrast enhancement was mild and varied from homogeneous to heterogeneous. A peripheral cystic component was found in two patients and was reported in only one previous case. Mass effect and white matter edema were marked to severe. Osteolysis of facial bones and extension into the facial soft tissues or retrobulbar space were not present in any of the cases, although this has been reported in the literature. CONCLUSION: A definitive diagnosis of esthesioneuroblastoma based on signal intensity or contrast behavior was not possible. Nevertheless, the presence of a mass in the caudal nasal cavity with extension into the neurocranium seems to be a feature highly suspicious of esthesioneuroblastoma. In contrast to other extra-cranial lesions, the extra-cranial mass was relatively small and destruction of facial bones seems to be rare.