Vertebral Body Length Research Articles

Clinical Characteristics of Spinal Epidural Abscess Accompanied by Bacteremia.

ObjectiveThe treatment of choice for spinal epidural abscess (SEA) generally is urgent surgery in combination with intravenous antibiotic treatment. However, the optimal duration of antibiotic treatment has not been established to date, although 4–8 weeks is generally advised. Moreover, some researchers have reported that bacteremia is a risk factor for failure of antibiotic treatment in SEA. In this study, we investigated the clinical characteristics of SEA accompanied by bacteremia and also determined whether the conventional 4–8 weeks of antibiotic treatment is sufficient. MethodsWe retrospectively reviewed the medical records and radiological data of 23 patients with bacterial SEA who underwent open surgery from March 2010 to April 2020. All patients had bacteremia preoperatively and underwent weeks of perioperative antibiotic treatments based on their identified organisms until all symptoms of infection disappeared. All patients underwent microbiological studies of peripheral blood, specimens from SEA and concomitant infections. The mean follow-up duration was 35.2 months, excluding three patients who died. ResultsThe male : female ratio was 15 : 8, and the mean age was 68.9 years. The SEA most commonly involved the lumbar spinal segment (73.9%), and the mean size was 2.9 vertebral body lengths. Mean time periods of 8.4 days and 16.6 days were required from admission to diagnosis and from admission to surgery, respectively. Concomitant infections more frequently resulted in delayed diagnosis (p=0.032), masking the symptoms of SEA. Methicillin-sensitive Staphylococcus aureus was the most commonly identified pathogen in both blood and surgical specimens. Seventeen patients (73.9%) showed no deficits at the final follow-up. The overall antibiotic treatment duration was a mean of 66.6 days, excluding three patients who died. This duration was longer than the conventionally advised 4–8 weeks (p=0.010), and psoas or paraspinal abscess required prolonged duration of antibiotic treatment (p=0.038). ConclusionSEA accompanied by bacteremia required a longer duration (>8 weeks) of antibiotic treatment. In addition, the diagnosis was more frequently delayed in patients with concomitant infections. The duration of antibiotic treatment should be extended for SEA with bacteremia, and a high index of suspicion is mandatory for early diagnosis, especially in patients with concomitant infections.

Sex Estimation of Typical Adult Vertebrae Morphology in Central China Based on CT Technique

Objective The morphological data of the second thoracic vertebra and the third lumbar vertebra were measured by computerized tomography （CT）. The sex differences were analyzed and the discrimination equation was obtained. Methods The data of 274 adults （203 cases from experimental group and 69 cases from validation group） from central China were collected. Four linear data （maximum transverse length of vertebral body, maximum longitudinal length of vertebral body, maximum transverse length of vertebral foramen, maximum longitudinal length of vertebral foramen）, one angle data （angle between spinous processes） and two area （vertebral foramen area, total cross-sectional area of vertebral body） data of the second thoracic vertebra and the third lumbar vertebra were collected, respectively. Then three ratios ［maximum transverse length/ maximum longitudinal length of vertebral body, maximum transverse length/ maximum longitudinal length of vertebral foramen, vertebral foramen area/ （total cross-sectional area of vertebral body-vertebral foramen area）］ and one angle （angle between spinous processes） were obtained. The discriminant equation was established for sexual discriminant analysis. Results The morphology of the second thoracic vertebra and the third lumbar vertebra was related with gender. Four single index discriminant formulae and eleven multi-index discriminant formulae were established. The 69 validation group samples were substituted into the formula for testing, and the maximum discriminant accuracy rate of the single-index discriminant formula was 75%. The maximum discriminant accuracy rate of multi-index discriminant formula was 83%. Conclusion It is feasible to conduct individual sex analysis by the morphological indexes of second thoracic vertebra and the third lumbar vertebra. The indexes have important application values in practice.

Comparison of Preoperative Pedicle Screw Measurement Between Computed Tomography and Magnet Resonance Imaging.

Pedicle screw fixation is commonly used in the treatment of spinal pathologies. While the biomechanical factors that affect bone fixation have been frequently described, questions remain as to which imaging modality is the ideal medium for preoperative planning. Due to its perceived superiority in assessing bony changes, computed tomography (CT) scan is assumed to be the gold standard for preparative planning, and we hypothesize that magnetic resonance imaging (MRI) is sufficiently accurate to predict screw length and diameter compared to CT. We retrospectively measured the length and diameter of vertebral bodies in the lumbar region in both MRI and CT and tested for differences between the modalities as well as for confounding effects of age, sex, and the presence of spondyloarthrosis. We found a significant difference in pedicle screw length between CT and MRI measurements for both sides. For the left pedicle, the mean difference was 1.89 mm (95% confidence interval [CI] -3.03 to -0.75; P < .002), while for the right pedicle, the mean difference was 2.05 mm (95% CI -3.27 to -0.84; P = .001). We also found a significant difference in diameter measurements between CT and MRI for the left pedicle (0.53 mm; 95% CI 0.13 to 0.93; P = .011) but not for the right pedicle (0.36 mm; 95% CI -0.06 to 0.78; P = .094). We identified no significant effect of sex, age or spondyloarthrosis on the results (P > .05). Pedicle screw planning measurements were more accurate using CT images compared to MRI images. CT scan remains the gold standard for pedicle screw planning in trauma surgery. When using MRI images, the surgeon should be aware of the differences in screw length and diameter compared to CT in order to avoid intra- and postoperative risks.

P41. Flexion-extension radiographs underestimate instability in patients with single-level lumbar spondylolisthesis. Comparing flexion-supine imaging may be more appropriate

BACKGROUND CONTEXT Most spine surgeons use flexion-extension radiographs in their surgical decision-making for patients with lumbar spondylolisthesis. However, this method may underestimate the instability at a lumbar segment. Unfortunately, insurance companies often use radiology reports of flexion-extension radiographs to determine eligibility for lumbar fusion and often refuse appropriate care based on obsolete criteria. The utility of lateral dynamic films remains controversial in this population. To the authors' knowledge, no prior study has compared Slip Percentage (SP) in standing versus supine positioning. PURPOSE To compare flexion-extension (FE) with standing-supine (SS) and Flexion-Supine (FSu) views in providing an evaluation of segmental lumbar instability for single level spondylolisthesis. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE Adult (>=18 years old) patients with single-level lumbar spondylolisthesis who underwent surgical treatment from 2016 to 2019. OUTCOME MEASURES Slip percentage differences and ventral instability. METHODS Consecutively collected adult (>=18 years old) patients with single-level lumbar spondylolisthesis who underwent surgical treatment from 2016 to 2019 were reviewed from a two-surgeon database. Anterior displacement (A) of a vertebra relative to the caudad vertebra was measured as a percentage of the sagittal length (B) of the caudad vertebral body (Slip Percentage, SP=100xA/B). Ventral instability was defined as an SP difference>8% as used in prior literature. Supine SP was calculated from sagittal Lumbar MRI. Chi-square/Fisher's Exact test and t-test were used for categorical and continuous variables. RESULTS Forty-four patients with lumbar spondylolisthesis who underwent surgery were identified. The cohort had a mean age of 57.3+-16.7 years and 66% of them were female. The majority had a slip grade of either 1 or 2 (Grade 1: 52.2%, Grade 2: 38.6%, Grade 3: 9.1%, Grade 4: 0%) and at the L4-5, 5-1 levels (L3-4: 2.3%, L4-5: 59.1%, L5-S1: 38.6%). The magnitude of change in SP was significantly highest in the FSu (12.7%) and SS (9.2%) groups, both of which were significantly higher compare with the traditional FE group (4.0%, P CONCLUSIONS Routine FE radiographs for lumbar spondylolisthesis may not be necessary and may underreport instability in single-level lumbar spondylolisthesis. SS and FSu parameters provide more sensitive measures of instability and may reduce unnecessary radiation exposure and costs. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

P0895THE RELATIONSHIP OF ARTERIAL CALCIFICATIONS IN CHRONIC KIDNEY DISEASE PATIENTS WITH INDIRECT ANTICOAGULANT INTAKE AND HEART MORBIDITY

Abstract Background and Aims In patients with chronic kidney disease (CKD), arterial calcification (AC) is a potential mechanism for the progression of cardiovascular disease. AC is common in CKD patients and is a consequence of mineral-bone disorders. Indirect anticoagulants or vitamin K deficiency lead to matrix γ-carboxyglutamate decarboxylation, which may potentiate vascular calcification formation. The impaired renal function and indirect anticoagulants intake may lead to vitamin K deficiency and increased AC. The aim of this study is to determine if oral intake of Acenocoumarol has influence on abdominal aorta calcium score (AACS) and the AC relation with atrial fibrillation (AF) and / or ischemic heart disease (IHD) morbidity. Method We observe 129 patients with CKD (glomerular filtration rate below 44 ml/min/1,73 m2, MDRD formula calculated). X - ray of the lateral abdominal aorta is performed for the AACS assessment according to L. I. Kauppila et al. method. The assessment of calcium score is formed by the involvement grade of each segment on the anterior and posterior wall of the vessel along the first four lumbar vertebrae. Calcification affecting less than 1/3 of the anterior wall of the aorta along the lumbar vertebral body receives 1 score and calcification extending over ½ of the vertebral body length receives 3 scores (total score - 24). The patients are distributed into three groups: I group with calcium score from 0 to 7, II - from 8 to 15 and III group - from 16 to 24. The data from assessed AACS are compared with Acenocoumarol intake and the presence/absence of AF and/or IHD. The results are processed with χ2 statistical analysis. Results One hundred twenty nine patients with CKD (95 males and 34 females) are included in the study. The patients data (mean, percentages, degrees, etc.) are summarized in tabl.1 and tabl. 2. Clinically significant is the correlation between the grades of AACS and Acenocoumarol intake (p &amp;lt; 0,05). With the calcium score increasing, the patients percentage treated with Acenocoumarol also increases (fig. 1). There is a moderate correlation (Cramer’s coefficient is 0,39) between the AACS grades and heart morbidity from AF and / or IHD (p &amp;lt; 0,05). The data shows that the higher calcium score is related with increased patients percentage with AF and / or IHD morbidity (fig. 2). In our study, vascular calcifications are found in the abdominal aorta walls in all of the observed patients. We found that a higher AACS is associated with an Acenocoumarol intake in CKD patients and corresponds to an increased morbidity of AF and / or IHD. Acenocoumarol intake may lead to increased AACS. The higher calcium score is associated with a higher incidence of AF and / or IHD morbidity. Conclusion The study outcome supported the hypothesis that the increased AC formation and cardiovascular morbidity high risk could be a reason for the limited vitamin K antagonists (acenocoumarol) use in CKD patients. Furthermore, vitamin K2 supplementation is reasonable and may reduce the progression of AC.

Effect of durotomy in dogs with thoracolumbar disc herniation and without deep pain perception in the hind limbs.

To determine the effectiveness of durotomy as an adjunct to surgical decompression in dogs with thoracolumbar intervertebral disc herniation (TL-IVDH) and loss of deep pain perception (DPP) in the hind limbs. Retrospective study. Dogs (n = 116) with TL-IVDH and loss of DPP treated with hemilaminectomy. Signalment, surgical site, recovery rate, incidence of progressive myelomalacia (PMM), time elapsed from onset of paraplegia of the hind limbs to surgery (TPS), and the length of area of hyperintensity of the spinal cord on magnetic resonance T2-weighted images compared with L2 vertebral body length (LHT2) were compared between dogs treated with hemilaminectomy alone and those treated with adjunct durotomy. Multivariate logistic regression analyses were used to test the association between outcomes and the external view of the spinal cord parenchyma after durotomy. The percentage of dogs regaining ambulation was greater when durotomy was performed (56.9%) than when dogs were treated with hemilaminectomy alone (38.5%; P = .04). In the hemilaminectomy group, 14 dogs died of suspected PMM, while no PMM was detected in the durotomy group. Durotomy, breed, surgical site, and LHT2 influenced recovery. No association was detected between age, sex, body weight, and TPS and recovery. Performing a durotomy in combination with decompression improved the return to function and prevented PMM in our clinical setting. Surgeons should consider durotomy in dogs with TL-IVDH and loss of DPP in hind limbs to improve surgical outcome.

Bolus epidural infusion improves spread compared with continuous infusion in a cadaveric porcine spine model

BackgroundThe administration of epidural anesthesia during labor is a common technique used to reduce the pain of childbirth. We sought to compare standard infusion strategies of continuous epidural infusions (CEI)...

RADIOLOGIC MEASUREMENT AND DETERMINATION OF KIDNEY-TO-VERTEBRA RATIOS AS A METHOD OF ESTIMATING RENAL SIZE IN SERVALS (LEPTAILURUS SERVAL)

Numerous conditions, from acute to chronic renal changes, have the potential to alter the renal size on radiographs. However, current literature does not provide any radiographic reference range for the normal renal size in the serval (Leptailurus serval). This retrospective study includes 13 healthy adult servals, seen between 2004 and 2017 at the UTCVM Veterinary Medical Center, deemed healthy based on physical examination and blood work. Orthogonal radiographs were anonymized, calibrated, and evaluated blindly by three observers of different experience levels. Renal and individual lumbar vertebral body lengths were measured on both orthogonal views, and ratios of kidney length to each lumbar vertebral length were calculated on both views. On the ventro-dorsal projection, the kidney length to L5 vertebra ratio had the lowest standard deviation (SD) with a mean of 1.82, SD of 0.27, and 95% confidence interval (CI) (1.63-2.00). On the lateral view, the kidney length to L3 vertebra ratio had the lowest SD with a mean of 2.03, SD of 0.25, and 95% CI(1.86-2.20). Statistically, all three observers were shown to be in agreement, indicating reproducibility of the measurements among observers with different levels of expertise.

The Optimal Screw Length of Lumbar Pedicle Screws during Minimally Invasive Surgery Fixation: A Computed Tomography-Guided Evaluation of 771 Screws.

Study DesignA retrospective study of radiographic parameters of patients who underwent lumbar spinal pedicle screw insertion.PurposeThe optimal length of pedicle screws is often determined by the lateral radiograph during minimally invasive surgery (MIS). Compared with open techniques, measuring the precise length of screws or assessing the cortical breach is challenging. This study aims to ascertain the optimal pedicle screw lengths on intraoperative lateral radiographs for L1–L5.Overview of LiteratureResearch has revealed that optimal pedicle screw length is essential to optimize fixation, especially in osteoporotic patients; however, it must be balanced against unintentional breach of the anterior cortex, risking injury to adjacent neurovascular structures as demonstrated by case reports.MethodsWe reviewed intra- and postoperative computed tomography scans of 225 patients who underwent lumbar pedicle screw insertion to ascertain which of the inserted screws were ‘optimal screws.’ The corresponding lengths of these screws were analyzed on postoperative lateral radiographs to ascertain the ideal position that a screw should attain (expressed as a percentage of the entire vertebral body length).ResultsWe reviewed 880 screws of which 771 were optimal screws. We noted a decreasing trend in average optimal percentages of insertion into the vertebral body for pedicle screws going from L1 (average=87.60%) to L5 (average=78.87%). The subgroup analysis revealed that there was an increasing percentage of screws directed in a straight trajectory from L1 to L5, compared to a medially directed trajectory.ConclusionsDuring MIS pedicle screw fixation, this study recommends that pedicle screws should not exceed 85% of the vertebral body length on the lateral view for L1, 80% for L2–L4, and 75% for L5; this will minimize the risk of anterior cortical breach yet maximize pedicle screw purchase for fixation stability.

Gross Morphology and Morphometrical Studies on the Vertebral Column of Indian Giant Flying Squirrel (Petaurista philippensis)

The present study was conducted on the gross anatomical features of the vertebral column of Indian giant flying squirrel (Petaurista philippensis). It belongs to the order Rodentia and Sciuridae family. The bones of the vertebral column were collected during the post-mortem examination at Veterinary College, Shivamogga, Karnataka. The vertebral formula was found to be C7, T12, L7, S3, Cy27. The foramen transversarium was noticed in all the cervical vertebrae except in C7. The width and length of the centrum were progressively increased from L1 to L7. Haemal arch and haemal processes were observed in Cy4 to Cy9 and Cy10 to Cy19 respectively. The variations in the neural spine, vertebral body length, and transverse process were observed in all the vertebrae. So, these variations in the vertebral column may be attributed for the specialized movements such as gliding, lifting and balancing the body of Indian giant flying squirrel.

The torg ratio of C3-C7 in African Americans and European Americans: A skeletal study.

The ratio between the sagittal diameter of the spinal canal and the sagittal diameter of the vertebral body, known as the "Torg ratio", is often used to test for spinal canal narrowing. Here, we investigate this ratio in a large population, consisting of two ethnicities, both sexes and three age groups. Measurements were taken on the dry cervical verterbrae (C3-C7) of 277 individuals using a digital apparatus allowing for the recording of 3D coordinates of a set of landmarks on the vertebral body. Vertebral body and vertebral foramen lengths were compared across the different subgroups. Vertebral body and vertebral foramen lengths differ significantly between males and females and between African Americans and European Americans. With age, the vertebral body length increases while the foramen length does not undergo significant changes. These anatomical differences are reflected in differences in the Torg ratio calculated for the different subgroups. In conclusion, our findings suggest that a hard cutoff on the Torg ratio used to define a pathological narrowing of the cervical spine should be adapted to the population the patients come from. Clin. Anat. 32: 84-89, 2019. © 2018 Wiley Periodicals, Inc.

A radiographic measurement of left atrial size in dogs

BackgroundThe dimensions of the left atrium in cases with mitral regurgitation are an indirect measurement of its severity. The objective of this study was to evaluate the value of a new radiographic measurement, the radiographic left atrial dimension (RLAD), for detecting left atrial enlargement (LAE) in dogs. Thirty one dogs without LAE and 46 dogs with LAE were recruited in a prospective fashion. Reference left atrium dimension was measured by standard left atrium to aorta ratio (LA/Ao) by 2D echocardiography. LAE was considered if LA/Ao > 1.6. Left atrium dimension was then quantified on lateral radiographs by measuring RLAD. Vertebral heart size (VHS) was measured and RLAD was obtained by drawing a line bisecting the 90 degrees angle defined by the long and short cardiac axes lines of the VHS, up to the dorsal edge of the left atrium and comparing its length to T4’s vertebral body length. The correlation of VHS and RLAD methods with LA/Ao was estimated, as well as their sensitivity and specificity for detecting LAE. Receiver Operating Characteristic (ROC) curves were used to estimate the optimal decision criteria for each method.ResultsA positive correlation was observed between RLAD and LA/Ao (r = 0.82). RLAD’s sensitivity and specificity for detecting LAE when evaluated at the optimal cut-off value, 1.8 vertebrae, were 93.5 and 96.8% respectively. RLAD showed high reproducibility and repeatability.ConclusionRLAD appears to be a clinically useful radiographic measurement for evaluating left atrial dimensions. RLAD would provide clinicians with a simple and cost-effective tool for evaluating and monitoring LAE.

Lumbar Schmorl's Nodes and Their Correlation with Spine Configuration and Degeneration.

The aim of this study was to reveal whether demographic aspect, vertebral morphometry, and spine degeneration are associated with lumbar Schmorl's nodes (SNs). A retrospective cross-sectional study was performed using data from the Department of Radiology (Carmel, Medical Center, Israel) for 180 individuals: age range between 40 and 99 years; 90 males and 90 females. All participants had undergone high-resolution CT scans for abdominal diagnostic purposes in the same supine position prior to our study, which enabled the processing of the scans in all planes and allowed a 3D reconstruction of the lower lumbar region. Eighty individuals (44.4%) had at least one SN along the lumbar spine, particularly at L3-4 level (30%). Vertebral body length (L1 to L3) and width (L1 and L4) were significantly greater in the SNs group compared to non-SNs group. On contrast, disc height (L3-4 and L4-5) was significantly lesser in SNs group than non-SNs group. SNs was significantly associated with smoking (X2= 4.436, P=0.02) and degenerative lumbar spinal stenosis (X2= 5.197, P=0.038). Moreover, the prevalence of SN was significantly greater in individuals with vacuum phenomenon and osteophytes formation (L1-2 to L4-5 levels). This study indicates that vacuum phenomenon on L3-4 (OR: 4.7, P=0.034), smoking habit (OR: 3.2, P=0.003), disc height loss of L4-5 (OR: 0.798, P=0.008), vertebral body length of L1 (OR: 1.37, P<0.001), and age (OR: 1.05, P=0.002) increase the probability of developing lumbar SNs.

Cervical Intervertebral Disk to Vertebral Body Ratios of Different Dog Breeds Based on Sagittal Magnetic Resonance Imaging.

Objective: To establish sagittal area and length reference values and ratios between apparently normal canine cervical vertebrae and intervertebral disks using magnetic resonance imaging.Sample: Retrospective evaluation of cervical vertebral column magnetic resonance imaging studies of 44 dogs representing 5 different breeds (Labrador Retriever, n = 10; French Bulldog, n = 10; Great Dane, n = 9; Chihuahua, n = 10; Dachshund, n = 5).Procedures: Mid-sagittal measurements of vertebral body and disk areas were obtained from C3 through C7 vertebrae and C2/C3 through C6/C7 intervertebral disks. Disk to vertebra area ratios were calculated and compared among dog breeds. Additionally, sagittal vertebral body and disk length measurements were obtained and disk to vertebra length ratios calculated. Inter and intra observer variability was assessed.Results: There were significant differences for disk to vertebral body area and length ratios between evaluated dog breeds and cervical vertebral locations (p < 0.001). Mean area ratio of Chihuahuas was significantly larger than all other breeds, while results from Dachshunds were only significantly different than Chihuahuas and Labrador Retrievers. Mean area ratios were statistically different between the cranial and caudal cervical vertebral locations. Regarding length ratios, results from Chihuahuas were significantly different than all breeds except Dachshunds. Mean length ratios were statistically different between all cervical locations, except C2/C3 compared to C3/C4. Intra- and interobserver variability was very good to excellent.Conclusion and Clinical Relevance: There are significant differences in area and length ratios between dog breeds. Differences also exist in area and length ratios between the cranial and caudal cervical vertebral column. These differences may play a role in the development of vertebral column diseases including intervertebral disk disease.

Transcranial magnetic motor evoked potentials and magnetic resonance imaging findings in paraplegic dogs with recovery of motor function.

BackgroundTranscranial magnetic motor evoked potentials (TMMEP) are associated with severity of clinical signs and magnetic resonance imaging (MRI) findings in dogs with spinal cord disease.HypothesisThat in initially paraplegic dogs with thoracolumbar intervertebral disc herniation (IVDH), MRI findings before surgery and TMMEPs obtained after decompressive surgery are associated with long‐term neurological status and correlate with each other.AnimalsSeventeen client‐owned paraplegic dogs with acute thoracolumbar IVDH.MethodsProspective observational study. TMMEPs were obtained from pelvic limbs and MRI (3T) of the spinal cord was performed at initial clinical presentation. Follow‐up studies were performed ≤ 2 days after reappearance of motor function and 3 months later. Ratios of compression length, intramedullary hyperintensities' length (T2‐weighted hyperintensity length ratio [T2WLR]), and lesion extension (T2‐weighted‐lesion extension ratio) in relation to the length of the 2nd lumbar vertebral body were calculated.ResultsTMMEPs could be elicited in 10/17 (59%) dogs at 1st and in 16/17 (94%) dogs at 2nd follow‐up. Comparison of TMMEPs of 1st and 2nd follow‐up showed significantly increased amplitudes (median from 0.19 to 0.45 mV) and decreased latencies (from 69.38 to 40.26 ms; P = .01 and .001, respectively). At 2nd follow‐up latencies were significantly associated with ambulatory status (P = .024). T2WLR obtained before surgery correlated with latencies at 2nd follow‐up (P = .04).ConclusionsTMMEP reflect motor function recovery after severe spinal cord injury.

Ultrasonographically determined renal values and comparisons to serum biochemistry renal variables in aged semi-captive cheetahs (Acinonyx jubatus)

BackgroundCheetahs in captivity have a high prevalence of chronic renal diseases. We ultrasonographically evaluated the renal volumes, a variety of renal dimensions, interarcuate artery resistive indices (RI) as well as aortic diameters and the length of the ventral aspect of the 6th lumbar vertebrae in 27 aged semi-captive anesthetized cheetahs. Renal size, dimensions and ratios were compared to urine specific gravity, serum creatinine and urea values.ResultsThere were minimal differences for all values between left and right kidneys. Mean kidney length was 65.1 mm (range 55.2–76.9) with left kidney length ratios to L6 length being 1.60 (range 1.27–2.06) and to the aortic diameter 7.69 (range 4.54–10.72). Significant correlations between left renal length as well as length:L6 ratio to creatinine values were found ((r − 0.66) and (r − 0.60) respectively). The mean RI values of the different sedation/anesthetic protocols ranged from 0.46–0.55.ConclusionsLeft renal length and L6 ventral vertebral body length as well as left kidney RI values should be routinely measured in all cheetah abdominal ultrasound examinations. These measurements, together with serum creatinine, urea and urine specific gravity values may be relatively sensitive indicators of early renal pathology in the absence of gross ultrasonographic changes.

Relationship between basivertebral foramen and retropulsed bone fragment in thoracolumbar burst fracture

Objective To clarify the relationship between the basivertebral foramen (BF) and the retropulsed bone fragment (RBF) in thoracolumbar burst fracture (TLBF) and further explain the mechanism of RBF formation. Methods From June 2013 to June 2016, Sixty-two patients suffering from TLBF with RBF were collected. The characteristics of RBF as well as the parameters of vertebral body were studied using CT reconstruction imaging. In the transverse images, the lengths of RBF (RL) and vertebral body (VL) were measured. In median sagittal images, the heights and widths of RBF (RH, RW) and vertebral body (VH, VW) were also obtained. The ratios of different parameters of RBF and vertebral body (RL/VL, RW/VW, RH/VH) were calculated, and then defined the location relationship of RBF and BF. Eight frozen cadaveric spine were selected and evaluated by Micro-CT scans. Each vertebral body was divided into three layers (Superior, Middle, Inferior). Each layer was further divided into 9 regions (R1-R9), named as SR1-SR9, MR1-MR9, IR1-IR9. Microarchitecture parameters of each region in each layer, including bone volume fraction (BV/TV), bone mineral density (BMD), trabecular connectivity (Conn.D), and trabecular number (Tb.N) and thickness (Tb.Th) were calculated, and their differences were also analyzed to see if the trabecular bone distribution would be affected by BF. In vitro study, burst fractures were simulated on cadaveric spines by using bursting fracture simulator, aiming to observe the RBF morphology and imaging findings to future investigate the relationship between RBF and BF. Results The length and height of RBF were close to half of vertebral body length and height (RL/VL: 0.497±0.059, RH/VH: 0.485±0.036). The width of RBF was usually one-third of vertebral body width (RW/VW: 0.319±0.025), which indicated that the fracture block was often located in the posterior of vertebral body above the BF. BV/TV, Tb.N in the MR2 and MR5 regions were lowest than other regions and the SMI of MR2 and MR5 was largest than others. SR5 was the lowest region in superior lawyer that was corresponded to regions most affected by burst fracture. In simulated burst fractures, the fracture line of RBF went across the vertex or upper surface of the BF and the lower boundaries of RBF were also the upper bound of the BF. Moreover, the damage sites of posterior longitudinal ligament were mainly located at the edge of the BF. Conclusion At the bone defect region, the BF is the weakest area in the vertebral body which may affect the distribution of trabecular bone surrounding it. When subjected to vertical violence, these regions undergo fracture first which impact the anterior and lower boundaries of RBF. Ultimately, RBF was produced upon the BF, involving all or part of the upper bound of the BF. Key words: Thoracic vertebrae; Lumbar vertebrae; Fractures, bone; Tomography, spiral computed

Determination of sex-related differences based on 3D reconstruction of the chinchilla (Chinchilla lanigera) vertebral column from MDCT scans

This study was undertaken to obtain and analyse, on the basis of sex, three-dimensional (3D) reconstructions obtained by a 3D computer program from two-dimensional (2D) vertebral column sections taken by multidetector computed tomography (MDCT) images, in the chinchilla. A total of 16 adult chinchillas (Chinchilla lanigera) of both sexes were used. The MDCT images were taken under general anaesthesia, and were then transferred to a personal computer on which 3D reconstructions were carried out using a 3D modelling program (Mimics 13.1). The volume, surface area and vertebral body length of each vertebra (except caudal region) forming the vertebral column were measured from the 3D models created. The ratios (in percentage) of the measurements of each vertebra (except the sacral ones) forming the vertebral column region (cervical part, thoracic part, lumbar part) were determined for statistical analysis. We detected significant differences (P &amp;lt; 0.05) between sexes in all vertebrae forming the vertebral column of the chinchilla with respect to volume, surface area and vertebral body length, except for C6 and L1. This study is the first to carry out 3D reconstructions of data obtained from CT images in the chinchilla and the obtained results contribute to a more detailed understanding of the anatomy of this species. Our strategy may also be useful for the design of experiments exploring the vertebral column in domestic mammals and humans.

SINGLE-SHOT TURBO SPIN ECHO PULSE SEQUENCE FINDINGS IN DOGS WITH AND WITHOUT PROGRESSIVE MYELOMALACIA.

Progressive myelomalacia is an uncommon type of ischemic, hemorrhagic spinal cord infarction. Diagnosis can be difficult, but prompt recognition is important. We hypothesized that cerebrospinal fluid signal attenuation on magnetic resonance (MR) images would be more extensive in dogs that developed progressive myelomalacia vs. control dogs. A retrospective analytic cohort study was designed. Dogs were included if they presented for acute paraplegia and loss of deep pain perception and had undergone MR imaging using both sagittal single-shot turbo spin echo (SSTSE) and standard sagittal T2-weighted fast spin echo (T2W) pulse sequences. Dogs were divided into progressive myelomalacia and control groups for comparisons. All MR examinations were evaluated by three reviewers blinded to patient outcome. Length of cerebrospinal fluid attenuation was recorded as a ratio to the length of the L2 vertebral body in SSTSE and T2W sequences (CSF:L2SSTSE and CSF:L2T2 , respectively). Length of intramedullary spinal cord hyperintensity was recorded as a ratio to the length of the L2 vertebral body in T2W sequences. A total of 21 dogs were included (five in the progressive myelomalacia group and 16 in the control group). The mean CSF:L2SSTSE attenuation value was significantly higher in dogs that developed progressive myelomalacia (CSF:L2SSTSE = 10.7) compared to controls (CSF:L2SSTSE = 5.4; P = 0.015). A cut off ratio of attenuation >7.4 provided optimal differentiation between groups in this study. Findings supported the conclusion that dogs with CSF:L2SSTSE ≤ 7.4 are unlikely to develop progressive myelomalacia while dogs with CSF:L2SSTSE > 7.4 are indeterminate for progressive myelomalacia.

RADIOGRAPHIC THORACIC ANATOMY OF THE RED PANDA (AILURUS FULGENS)

The red panda ( Ailurus fulgens ) is classified as an endangered species by the International Union for Conservation of Nature and Natural Resources. The natural distribution of the red panda is in the Himalayas and southern China. Thoracic diseases such as dirofilariasis, hypertrophic cardiomyopathy, tracheal obstruction, lung worm infestation, and pneumonia have been reported in the red panda. The aim of this study was to describe the normal radiographic thoracic anatomy of captive red pandas as a species-specific reference for routine health examinations and clinical cases. Right lateral (RL) and dorsoventral (DV) inspiratory phase views of the thorax were obtained in 11 adult captive red pandas. Measurements were made and ratios calculated to establish reference ranges for the mean vertebral heart score on the RL (8.34 ± 0.25) and DV (8.78 ± 0.34) views and the mean ratios of the caudal vena cava diameter to the vertebral body length above tracheal bifurcation (0.67 ± 0.05) and tracheal diameter to the width of the third rib (2.75 ± 0.24). The majority of animals (10/11) had 14 thoracic vertebrae, except for one animal that had 15 thoracic vertebrae. Rudimentary clavicles were seen in 3/11 animals. The ovoid, oblique cardiac silhouette was more horizontally positioned and elongated in older animals. A redundant aortic arch was seen in the oldest animal. The trachea was seen with mineralized cartilage rings in all animals. The carina was clearly seen in the majority of animals (10/11). Variations exist in the normal radiographic thoracic anatomy of different species. Knowledge of the normal radiographic thoracic anatomy of the red panda should prove useful for routine health examinations and in the diagnosis of thoracic diseases.