Diagnostic accuracy and inter-observer agreement with the CO-RADS lexicon for CT chest reporting in COVID-19.

PURPOSE: To measure the diagnostic accuracy and inter-observer agreement with the use of COVID-19 Reporting and Data System (CO-RADS) for detection of COVID-19 on CT chest imaging. METHODS: This retrospective study included 164 consecutive patients with clinical suspicion of COVID-19 in whom a CT chest examination was performed at a single institution between April 2020 and July 2020. Of them, 101 patients was RT-PCR positive for COVID-19. Six readers with varying radiological experience (two each of chest radiologists, general radiologists, and radiologists in training) independently assigned a CO-RADS assessment category for each CT chest study. The Fleiss' K was used to quantify inter-observer agreement. The inter-observer agreement was also assessed based on the duration of onset of symptoms to CT scan. ROC curve analysis was used to determine the diagnostic accuracy of CO-RADS. The area under curve was calculated to determine the reader accuracy for detection of COVID-19 lung involvement with RT-PCR as reference standards. The data sets were plotted in ROC space, and Youden's J statistic was calculated to determine the threshold cut-off CO-RADS category for COVID-19 positivity. RESULTS: There was overall moderate inter-observer agreement between all readers (Fleiss' K 0.54 [95% CI 0.54, 0.54]), with substantial agreement among chest radiologists (Fleiss' K 0.68 [95% CI 0.67, 0.68]), general radiologists (Fleiss' K 0.61 [95% CI 0.61, 0.61]), and moderate agreement among radiologists-in-training (Fleiss' K 0.56 [95% CI 0.56, 0.56]). There was overall moderate inter-observer agreement in early disease (stages 1 and 2), with cumulative Fleiss' K 0.45 [95% CI 0.45, 0.45]). The overall AUC for CO-RADS lexicon scheme to accurately diagnose COVID-19 yielded 0.92 (95% CI 0.91, 0.94) with strong concordance within and between groups, of chests radiologists with AUC of 0.91 (95% CI 0.88, 0.94), general radiologists with AUC 0.96 (95% CI 0.94, 0.98), and radiologists in training with AUC of 0.90 (95% CI 0.87, 0.94). For detecting COVID-19, ROC curve analysis yielded CO-RADS > 3 as the cut-off threshold with sensitivity 90% (95% CI 0.88, 0.93), and specificity of 87% (95% CI 0.83, 0.91). CONCLUSION: Readers across different levels of experience could accurately identify COVID-19 positive patients using the CO-RADS lexicon with moderate inter-observer agreement and high diagnostic accuracy.

Effects of extremity positioning on radiographic evaluation of femoral tunnel location with digitally reconstructed femoral lateral radiographs after anterior cruciate ligament reconstruction.

BACKGROUND: Radiographic imaging is a valuable tool in clinical practice for quick anatomical assessment. We aimed to radiographically assess (A) the anterior cruciate ligament (ACL) graft tunnel location after anatomic single-bundle (SB) reconstruction and (B) the effects of extremity positioning on the localization of the orifice of the tunnel in the distal femur in comparison with Blumensaat's line (BL). METHODS: Three-dimensional computed tomography (3D CT) scan examinations of 22 knees of 22 subjects were evaluated. The 3D CT scan data was used to digitally reconstruct the true lateral radiographs. Graft tunnel location on the distal femoral shaft along the Blumensaat's line and perpendicular to it were assessed on these radiographs. The femur was digitally rotated to simulate varus, valgus, internal rotation and external rotation in 5-degree increments from 0 to 20-degree. At each incremental rotated position of the femur, position of the ACL graft tunnel was calculated relative to BL and the difference from the true lateral x-ray was estimated. RESULTS: The position of the tunnel in the distal femur was 30.6 (±4.4) % along BL and 33.1 (±5.4) % perpendicular to BL. Ten and more degree of external, internal, valgus and varus rotations significantly affected the estimates of tunnel position (P < 0.05). CONCLUSIONS: Femoral tunnel location can be reliably estimated from lateral radiographs after anatomic SB ACL reconstruction. Although, ten or more degree of rotations can introduce significant inaccuracies in tunnel location estimates, our study suggests that BL is overall reliable for assessing location of the distal femoral tunnel. LEVEL OF EVIDENCE: Level 2b (Retrospective Cohort Study).

Rare case of multiple aggressive vertebral hemangiomas.

A case of a 42-year-old man with back pain associated with left radiculopathy and infiltrative mass involving the T12 and L5 vertebrae is described. Magnetic resonance imaging (MRI) and computed tomography indicated aggressive hemangiomas involving the T12 and L5 vertebrae. Three-year follow-up by imaging indicated minimally increased aggressiveness of the L5 lesion without any significant change in appearance of the T12 lesion thus, confirming the initial diagnosis of multiple aggressive vertebral hemangiomas.

Retrospective magnetic resonance imaging evaluation of fatty filum terminale in Kuwaiti population.

OBJECTIVE: Thickened fatty filum terminale (FFT) can cause tethered cord syndrome (TCS) and can be easily diagnosed on magnetic resonance (MR) imaging. We aimed to assess a) the incidence, distribution and clinical significance of the incidentally detected FFT in Kuwaiti population and b) the relationship between degenerative disk disease (DDD) and thickness of the FFT. MATERIALS AND METHODS: A retrospective study was planned at Jaber Al Ahmad Armed Forces Hospital, Kuwait involving 1111 patients. A 1.5T GE machine was used for MR imaging to acquire multiplanar MR sequences. MR images of lumbar spine in 1111 subjects were reviewed and location, size, tightness of FFT, the DDD and clinical details were evaluated. RESULTS: FFT was observed in 43 out of 1111 (3.9%) subjects based on MRI, out of which 11 were females and 32 were males. The mean distance between the tip of conus medullaris and the FFT was 41 mm. The mean diameter of the FFT was 1.74 mm. 40 of 43 patients had DDD of varying severity on MR images and no significant or appreciable slackness of FFT was observed in these cases. There were no clinical symptoms related to FFT associated with degenerated disks. CONCLUSION: FFT is frequently observed in Kuwaiti male population. No significant slackness of FFT was observed in cases with varying severity of DDD. There were no clinical symptoms related to FFT with or without degenerated disks.

A rare case of cleidocranial dysplasia presenting with failure to thrive.

Cleidocranial dysplasia (CCD) is a rare (1:1,000,000) congenital condition secondary to spontaneous mutation (40%) or autosomal dominant inheritance (60%) affecting skeletal and dental systems. Hypomineralization of the hypoplastic clavicles and/or cranium is the major feature observed by prenatal ultrasound. Radiologically clavicles are hypoplastic or absent in chest X-ray. Delayed closure of the fontanelle and the skull sutures in pediatric and adolescent population and increased mobility of shoulders in all age groups (exhibited by the ability to bring shoulders close to each other) are prominent clinical diagnostic features of CCD. The diagnosis of CCD is often missed or significantly delayed. The management of CCD involves a multidisciplinary approach and its early diagnosis is essential to select an optimum plan and therapeutic benefit. We present here a case of CCD in a 17-month-old girl referred to us for investigation of below average weight and height gain; we stress on the usefulness of early diagnosis in the management of CCD and discuss current management concepts.

Computed tomography and magnetic resonance imaging features of a rare case of a primary epidermoid tumor of the jugular foramen.

We present computed tomography (CT) and magnetic resonance imaging (MRI) features of a very rare case of a primary epidermoid tumor of the jugular foramen (JF). A 45-year-old male patient presented with gradually progressive vertigo and tinnitus. CT and MRI scans revealed a 3.5 cm right-sided JF tumor with characteristic bright signal (restricted diffusion) on diffusion-weighted MRI (DWI). DWI may be useful in accurately differentiating the lesion from other cystic neoplasms of the JF. We describe the imaging features of intracranial epidermoid and JF tumors and discuss its differential diagnosis.

Smaller anterior cruciate ligament diameter is a predictor of subjects prone to ligament injuries: an ultrasound study.

PURPOSE: To test if diameter of normal anterior cruciate ligament (ACL) can be measured by ultrasound (US), to see if there is a relationship between smaller ACL diameter and ACL injury, and to assess agreement between radiologists in measuring ACL diameter in cases and matched controls. MATERIALS AND METHODS: In this ethics committee-approved study, maximum diameter of ACL near tibial insertion site was measured by static and dynamic US study in 25 normal contralateral knees of subjects who suffered noncontact ACL injury and in 25 matched control subjects. RESULTS: ACL was visualized as a thick linear hypoechoic band inserted approximately 11 mm caudal to the tibial plateau and the intercondylar eminence. Maximum diameter of contralateral ACL near tibial insertion site among injured subjects was significantly smaller than in noninjured subjects (0.62 ± 0.07 cm versus 0.81 ± 0.06 cm; P < 0.0001). In the regression analysis, the diameter of ACL near tibial insertion site was found significantly proportional to body weight and not significantly associated to height, gender, and age. CONCLUSION: Diameter of normal ACL near tibial insertion site can be measured by US and the maximum diameter is significantly smaller among subjects with noncontact ACL injury. US is a promising modality that can be used as an excellent screening test to detect subjects especially aspiring athletes prone to ACL injury. Very strong agreement was observed between radiologists in measuring ACL diameter.

First Report of Preoperative Imaging Diagnosis of a Surgically Confirmed Case of Valentino's Syndrome.

Perforation of a duodenal ulcer (DU) into the retroperitoneal space presenting with clinical features of acute appendicitis is known as Valentino's syndrome. Post duodenal perforation, the gastric and duodenal fluids tend to settle in the right paracolic gutter causing peritonitis and clinically mimicking acute appendicitis. Only three cases of Valentino's syndrome have been reported till date in the published literature and there is only one previous report of its preoperative imaging diagnosis. To our knowledge, this is the first reported case of preoperative imaging diagnosis in a surgically confirmed case of Valentino's syndrome. In most cases, patients with undiagnosed Valentino's syndrome are operated for acute appendicitis, and on finding a normal appendix, search is made for the cause of peritonitis, which then leads to retroperitoneal perforation of duodenum. The diagnosis of Valentino's syndrome by computed tomography (CT) imaging is easy and can help in avoiding the surgery or directing the surgeon directly to the repair of the duodenal perforation. It is, therefore, essential for emergency physicians, surgeons, and radiologists to know about this entity and consider it in the differential diagnosis.

Rare case of reversible acute symmetrical lesions of the bilateral Basal Ganglia associated with diabetic nephropathy and chronic renal failure.

Reversible acute symmetrical basal ganglial lesion on magnetic resonance imaging and/or computed tomography in cases of diabetic nephropathy and chronic renal failure exhibiting acute onset of movement abnormalities like chorea is a very rare entity. It has characteristic clinical and imaging features. Only 29 cases are described in the literature, including the current one. These cases are predominantly Asian patients from the Far East and only one Asian Indian patient has been described. We report the second Asian Indian case of this condition and describe its various clinical and imaging features. Our aim is to educate the clinicians and radiologists about this condition, so that more such cases can be detected.

Magnetic resonance imaging features of brain and spinal cord injury in a fatal case of isopropanol intoxication.

A 60-year-old man presented with headache, dizziness, and disorientation one day after consumption of isopropanol along with ethanol. Computed tomography (CT) of the brain performed immediately was unremarkable. The patient collapsed within the hospital 30 minutes after the CT scan was done, and remained comatose until death, showing no improvement with symptomatic treatment. Magnetic resonance imaging of the brain and spine done 6 days after admission revealed bilaterally symmetrical hyperintensities involving the cerebral and cerebellar cortex and white matter, basal ganglia, thalami, and brainstem on T2-weighted, fluid attenuated inversion recovery and diffusion weighted images; similar hyperintensities were seen involving the swollen and edematous cervical spinal cord and cerebellar tonsillar herniation compressing the proximal cervical cord. Petechial hemorrhages were also noted within the brainstem. These features are compatible with toxic injury to the brain and cervical spinal cord. To our knowledge, the magnetic resonance imaging features of brain and spinal cord injury and cerebellar tonsillar herniation, secondary to isopropanol intoxication have not been reported in the published literature before.

Rare case of pneumorrhachis, pneumomediastinum, pneumothorax, and surgical emphysema secondary to bronchial asthma.

Air localized within the spinal canal is called pneumorrhachis. In the case of pneumorrhachis, air can be present in the extradural, the intradural, or the subarachnoid space of the spinal canal. The air within the soft tissue of the posterior mediastinum may dissect along fascial planes, through the intervertebral neural foramina, and into the extradural or the subarachnoid space. Nontraumatic pneumorrhachis is a rare presentation. Most of the time, pneumorrhachis is asymptomatic, remains localized, and resolves spontaneously. There are very few reports of combined presence of pneumomediastinum and extradural pneumorrhachis not associated with thoracic injury in the published literature. We report a rare case of pneumorrhachis, pneumomediastinum, pneumothorax, and surgical emphysema in an adult female patient developed after a bout of violent cough related to bronchial asthma.

First report of MRI findings in a case of an autoamputated wandering calcified ovary.

An autoamputated wandering calcified ovary (AWCO) is an extremely rare cause of abdominal calcification in the pediatric population. We present the magnetic resonance imaging (MRI) features of AWCO in a child. To our knowledge, the MRI features of AWCO have not been previously described in the published literature. Our case report indicates that the MRI findings are characteristic in the diagnosis of an AWCO and can completely obviate the need for invasive procedures in this mostly benign disease. An AWCO should be considered in all cases of mobile calcific opacities on radiographs in female patients. We advise that MRI be conducted in all suspected cases of AWCO for accurate and noninvasive diagnosis, and regular follow-up should be performed with ultrasound. The findings in our case report have the potential to change the course of investigations and management in suspected cases.

A Rare Case of Near Complete Regression of a Large Cervical Disc Herniation without Any Intervention Demonstrated on MRI.

There are very few reported cases of regression of large cervical disc herniation without any intervention-the so-called spontaneous regression, demonstrated using MRI. We report a rare and interesting case of MRI that demonstrated near complete regression of a large herniated cervical intervertebral disc, without any surgical treatment.

A unique case of left second supernumerary and left third bifid intrathoracic ribs with block vertebrae and hypoplastic left lung.

Intrathoracic rib (IR) is a very rare anomaly in which a normal, an accessory, or a bifid rib lies within the chest cavity and may originate from a vertebra or a rib. It is more commonly present on the right side, and sometimes it may be associated with vertebral anomalies. Only 50 cases have been reported to date in the literature. In most cases, the IR is an isolated finding; it is incidentally detected and is asymptomatic. The IR can be easily missed on a chest radiograph and can be mistaken initially for a pleural lesion, lung consolidation, other peripheral lung parenchymal lesions, or a bony lesion. It is, therefore, essential for physicians and radiologists to know about this entity and consider it in the differential diagnosis, to avoid further evaluation and unnecessary investigations. We present a unique case of three intrathoracic ribs, a left second supernumerary rib, left third depressed normonumerary rib, and bifid arm of the left third rib, with block vertebrae and hypoplastic left lung. To our knowledge, this is the first such case presentation in the published literature.

A Rare Case of Pericallosal Lipoma Associated with Bilaterally Symmetrical Lateral Ventricular Choroid Plexus Lipomas without Corpus Callosal Anomalies.

Lipomas constitute less than 5% of primary brain tumors. Pericallosal lipomas (PCLp) constitute almost half of all intracranial lipomas. Corpus callosal anomalies commonly occur in cases with PCLps. Although PCLp is often described as corpus callosal lipoma, it is most often pericallosal in location. PCLps may have calcification in the periphery and may continue into lateral ventricles, which is a very rare presentation. We observed a case of PCLp with peripheral calcifications associated with PCLp continuing as bilaterally symmetrical lateral ventricular choroid plexus lipomas (CPLp) without any corpus callosal or other central nervous system anomalies, and as this is not been previously reported, we are presenting it. The appearance of PCLp in this case does not correspond to the descriptions of any of the existing morphological types (anterior and posterior) of classification of PCLps; it is rather mixed, where PCLp occupies both anterior and posterior locations around the corpus callosum.