IS THE “U-SIGN” RADIOLOGIC FEATURE OF A POSTERIOR CRUCIATE LIGAMENT TIBIAL AVULSION FRACTURE?

ABSTRACT Objective: By analyzing our cases of posterior cruciate ligament (PCL) tibial avulsion fracture, we noted that a U-shaped image was present in the anteroposterior plain radiographs view of the affected knee, even in cases where the profile view of the knee had been inconclusive as to tibial PCL avulsion fracture, a “hidden” fracture. Therefore, we aimed to investigate whether there was an anatomical correlation between this radiological U sign and the tibial insertion of the PCL and to ascertain the intra- and inter-rater reliability of this sign in clinical practice. Methods: The data of the widths and heights area of the PCL tibial insertion area, and the U sign area were measured and compared to the largest width of the tibia. Two moreover, the reliability and reproducibility of this imaging were analyzed. Results: The areas height of the U-sign area and the anatomical insertion area of the posterior cruciate ligament showed no difference, and both were topographically located in the two central quarters of the proximal end of the tibia. The radiographic assessment showed excellent Kappa agreement rates between interobserver and intraobserver, with high reliability and reproducibility. Conclusion: The U sign is a radiographic feature of PCL tibial avulsion fracture seen on the radiograph AP view, there is a high association between the ratios of the U-sign area height in the X-ray and the anatomical height of the PCL tibial insertion site MRI with the largest width of the proximal tibia. The radiographic U sign showed excellent rates of interobserver and intraobserver agreement with Kappa values higher than 0.8. Level of Evidence IV; Dignostic Studies - Investigating a Diagnostic Test.

Differential Contribution of the Medial and the Lateral Side of the Joint to Symptoms in Knee Osteoarthritis: A Radiographic and Laboratory Analysis in the Nagahama Study

Objective: This cross-sectional study aimed to explore the differences of the medial and lateral sides of the knee joint and precise radiographic abnormalities in contribution to the knee pain and clinical outcomes. Design: Participants 60 years or older who underwent radiographic evaluation were included. Knee radiography was assessed using grading systems of the Osteoarthritis Research Society International (OARSI) atlas. The Japanese Knee Osteoarthritis Measure (JKOM) was evaluated as clinical outcomes. Serum high-sensitivity C-reactive protein (hsCRP) was used to evaluate systemic inflammation. We divided the participants into normal, medial-, lateral-, and medial & lateral-OA types and compared their JKOM using an analysis of covariance. Furthermore, we analyzed the relationship between the knee pain and stiffness of JKOM and the grading of each radiographic feature using a multiple regression model. Results: Lateral- and medial & lateral-OA groups had a significantly worse symptoms in the total and the pain score, especially in movement subscales, in JKOM score. Lateral-OA groups had higher hsCRP than medial-OA group. Multivariate analysis showed that medial joint space narrowing (JSN), and lateral femoral and tibial osteophytes significantly affected knee pain (adjusted odds ratios: 1.73, 1.28, and 1.55, respectively). The radiographic changes are associated with pain more in JSN in the medial side and osteophytes in the lateral side. Conclusion: Lateral- and medial & lateral-OA groups showed worth symptom. In addition, medial JSN and lateral osteophytes have potent effects on the knee pain.

Gross and radiographic assessment of foot with claw disorders in culled cattle at Nsukka abattoir

Claw disorders are either infectious or non-infectious which have been found to be the cause of more than 90% of all lameness cases observed in dairy cattle. Against this background, descriptive and cross-sectional study was to determine the common radiographic features of claws with gross disorders using abattoir samples. A total of 40 claws were collected from Nsukka abattoir. The claws were examined for identification of different types of gross lesions. Two radiographic exposures, dorso-plantar and lateral views of each of the claws were taken and evaluated for radiographic changes. White line degeneration (WLD), sole erosion and horn heel erosion were the most prevalent gross lesions with 35%, 30% and 20% prevalent rates respectively. Bulb erosion and claw wall fissure were the least occurred claw disorders with 5% and 5% occurrence. Infectious claw disorders (55%) had a relatively higher occurrence than the non-infectious disorders (45%). The most prominent radiographic abnormalities were noted in the second (PII) and third phalanxes (PIII) region. The radiographic changes were sinking of PIII (10%) subluxation of PII (5%), foreign body penetration (15%), exostoses (5%) of the pastern (PII) bone. Laminitis occurred in 30% of the sampled claws. Concurrent appearance of more than one radiographic feature in a single claw was noted in the claw samples. In conclusion, radiographic examination revealed that typical changes of chronic laminitis were among the most common pathological features recorded. Les troubles des griffes sont soit infectieux, soit non infectieux, ce qui s'est avéré être la cause de plus de 90% de tous les cas de boiterie observés chez les bovins laitiers. Dans ce contexte, une étude descriptive et transversale visait à déterminer les caractéristiques radiographiques communes des griffes présentant des troubles macroscopiques à l'aide d'échantillons d'abattoir. Au total, 40 griffes ont été collectées à l'abattoir de Nsukka. Les griffes ont été examinées pour identifier différents types de lésions macroscopiques. Deux expositions radiographiques, vues dorso-plantaire et latérale de chacune des griffes ont été prises et évaluées pour les changements radiographiques. La dégénérescence de la ligne blanche (le 'WLD'), l'érosion de la sole et l'érosion du talon de la corne étaient les lesions macroscopiques les plus fréquentes avec respectivement 35%, 30% et 20% de taux de prévalence. L'érosion des bulbes et la fissure de la paroi des griffes ont été les moins affectées des griffes avec 5% et 5% d'occurrence. Les troubles infectieux des griffes (55%) avaient une fréquence relativement plus élevée que les troubles non infectieux (45%). Les anomalies radiographiques les plus importantes ont été notées dans la région de la deuxième (le 'PII') et de la troisième phalange (le 'PIII'). Les changements radiographiques étaient la descente de la subluxation 'PIII' (10%) du 'PII' (5%), la pénétration de corps étrangers (15%), les exostoses (5%) du paturon (le 'PII'). Une laminite est survenue dans 30% des griffes échantillonnées. L'apparition simultanée de plus d'une caractéristique radiographique dans une seule griffe a été notée dans les échantillons de griffe. En conclusion, l'examen radiographique a révélé que les changements typiques de la fourbure chronique faisaient partie des caractéristiques pathologiques les plus courantes enregistrées.

Radiological diagnosis of microcolon in a 5-day old neonate: a case report

Microcolon is a radiographic feature of a low intestinal obstruction that result from intrauterine underutilization or what is term unused colon. The finding of microcolon on contrast enema study in newborn with distended abdomen usually suggests jejunoileal obstruction, jejunoileal atresia, meconium ileus, or occasionally totals colonic agangliosis. We are therefore presenting this case to highlight the wonders that imaging will perform in prompt diagnosis and management of this condition.

A false alarm of COVID-19 pneumonia in lung cancer: a case report of anti-PD-1 related pneumonitis and literature review

Background: The fatal toxicity of anti-PD-1/PD-L1 agents is pneumonitis. The diagnosis consists of the history of immunotherapy, clinical symptoms and presentation of computed tomography (CT) imaging. The typical CT findings include ground-glass opacities. Based on the similar radiographic feature with 2019 Novel Coronavirus (COVID-19) pneumonia, clinicians are cautious to evaluate diagnosis especially in COVID-19 epidemic areas. Case presentation: Herein we report a 67-year-old male patient with advanced non-small cell lung cancer developed pneumonitis post Sintilimab injection. The dyspnea appeared at the 15th day of close contact with his son who returned from Wuhan, but not accompanied with fever. The chest CT indicated peripherally subpleural lattice opacities at the inferior right lung lobe and bilateral thoracic infusion. The real-time reverse-transcription polymerase-chain-reaction (RT-PCR) from double swab samples within 72 hours remained negative. The patient was thereafter treated with prednisolone and antibiotics for over two weeks. Thereafter the chest CT demonstrated the former lesion almost absorbed, in line with prominently falling CRP level. The anti-PD-1 related pneumonitis with bacterial infection was diagnosed finally based on the clinical evidence and good response to the prednisolone and antibiotics. Conclusion: Both ani-PD-1 related pneumonitis and COVID-19 pneumonia harbor the common clinical symptom and the varied features of CT imaging. Differential diagnosis was based on the epidemiological and immunotherapy histories, RT-PCR tests. The response to glucocorticoid can indirectly help the diagnosis.

Clinical and Radiographic Findings of Septic Physitis in Foals

The objective of this review is to detail the clinical and radiographic features of septic physitis in foals. Medical records were evaluated from 2008 to 2018 of cases that had septic physitis based on a combination of clinical and radiographic findings. Ten foals were diagnosed with septic physitis. In 8 of 10 foals, presence of a discrete, focal, irregular radiolucency centred on the physis and extending into the epiphysis and metaphysis was present. In the remaining two foals, subtle irregularity and diffuse radiolucency along the length of the physis was present. Three foals were able to later perform athletic function and two were sound but not in training (mean follow-up = 12 months). Overall, a distinguishing radiographic feature of septic physitis in foals is the presence of a focal radiolucency centred on the physis which is associated with the epiphysis and metaphysis consistent with osteolysis.

SAT-143 Missed Pituitary Apoplexy in a HIV Patient

Background: Pituitary hemorrhage has a prevalence of up to 25% in macroadenomas. In apoplectic hemorrhage, loss of pituitary function is associated with significant mortality. Sudden hemorrhagic enlargement of a preexisting adenoma compresses surrounding structures; ophthalmoplegia, mydriasis and ptosis occur when cranial nerves in the cavernous sinus are affected. The classic clinical syndrome of headache, visual deficits, altered mental status and hypopituitarism, combined with imaging, confirms the diagnosis of pituitary apoplexy. Clinical Case: A 73 year-old smoker with a history of transsphenoidal surgery 20 years ago for a pituitary adenoma, HIV (CD4 928), hypertension, diabetes, coronary artery disease presented with two days of altered mental status, lethargy and headaches. Patient was febrile to 104.1°F on arrival. Head CT was done prior to a lumbar puncture, which showed a 1.7 x 2.1 x 2.2 cm pituitary mass. CSF analysis was positive for xanthochromia, and revealed 220 RBCs, 275 WBCs, glucose 143 mg/dL, protein 154 mg/dL and an opening pressure of 9 mm H20. Meropenem and vancomycin were started for presumed meningitis. A hypopituitary state was found on labs: prolactin 1.9 ng/mL (4.6–21.4 ng/mL), ACTH 3.2 pg/mL (7.2–63.3 pg/mL), cortisol 3.6 ug/dL, TSH 0.164 uIU/mL (0.27–4.0 uIU/mL), free T4 0.6 ng/dL (0.7–1.5 ng/dL), T3 0.3 ng/mL (0.6–1.6 ng/mL), IGF-1 33 ng/mL (41–179 ng/mL), total testosterone 4 ng/dL (193–740 ng/dL), LH 0.3 mIU/mL and FSH 1.2 mIU/mL. Subsequent MRI showed a 2.2 x 2.4 x 2.9 cm pituitary macroadenoma extending into the suprasellar region with mass effect on the optic chiasm and lateral displacement of the cavernous sinus segment of internal carotid arteries bilaterally. An ophthalmologic exam could not be performed due to altered mentation. Endocrinology recommended cosyntropin testing to assess for adrenal insufficiency. The following day, the patient developed a fixed and dilated right pupil, and was taken to the OR for emergent decompression. IV dexamethasone and levothyroxine were started post-operatively. Conclusion: Differential diagnoses of pituitary apoplexy include bacterial meningitis and subarachnoid hemorrhage with aneurysmal rupture. A nonpupil-sparing third nerve palsy suggests a mass lesion. Given his symptoms and xanthochromia, this patient likely presented with pituitary apoplexy that was overlooked on initial scans. Hemorrhage that is iso-dense to normal brain tissue would not have the typical “pituitary ring sign”, a radiographic feature of peripheral enhancement around a non-enhancing infarcted center. Predisposing factors include hypertension, diabetes mellitus, pituitary dynamic testing, bromocriptine, estrogens or radiotherapy. This patient had multiple comorbidities. A lumbar puncture possibly worsened preexisting pituitary apoplexy, acutely expanding the area of hemorrhage and causing compressive symptoms.

Unusual Imaging Features of Dentigerous Cyst: A Case Report

Dentigerous cysts (DC) are cystic lesions radiographically represented by a well-defined unilocular radiolucent area involving an impacted tooth crown. We present an unusual radiographic feature of dentigerous cyst related to the impacted mandibular right second molar, in a 16-year-old patient, which suggested an ameloblastoma or odontogenic keratocyst (OKC) because of its multilocular appearance seen on the panoramic radiography. A multi-slice computed tomography (MSCT), however, revealed a unilocular lesion without septations, with an attenuation coefficient from 3.9 to 22.9 HU suggesting a cystic lesion. Due to its extension, a marsupialization was performed together with the histopathological analysis of the fragment removed which suggested a dentigerous cyst. Nine months later, the lesion was reduced in size and then totally excised. The impacted mandibular right second molar was also extracted. Histopathological examination confirmed the diagnosis of a dentigerous cyst. One year later, the panoramic radiography showed a complete mandible bone healing. Large dentigerous cysts can sometimes suggest other more aggressive pathologies. Precise diagnosis is important to avoid mistakes since DC, OKC and ameloblastoma require different treatments. Histological examination is, therefore, essential to establish a definitive diagnosis. In our case, MSCT and the tissue attenuation coefficient analysis contributed to guide the diagnosis and management of the dentigerous cyst.