 Hello everyone, I am Dr. Priyanka, a final year PG resident at Atulbirari Vajpayee Institute of Medical Sciences and Dr. Ramanohar Lohya Hospital, New Delhi. The topic of my paper is CT imaging spectrum of CVJ anomalies, a pictorial essay. The aim of this study is to outline the normal anatomy of the craniovertibular junction and to study the various CVJ anomalies. Craniovertibular junction consists of basal part of occipital bone, atlas and axis vertebra. Being the transit zone between the cranium and spine, it is the most complex and dynamic area of the cervical region. It is related with major neurovascular structures. Congenital malformations associated with this causes serious neurological and vascular deficit and may require surgical intervention. CVJ anomalies are common in all age groups and clinical features are often delayed up to second or third decade. The study was conducted in the Department of Radio Diagnosis at Atulbirari Vajpayee Institute of Medical Sciences and Dr. Ramanohar Lohya Hospital, New Delhi. Between 1st July 2021 to 30th August 2022, in the current study, we screened 60 patients with suspected anomalies of CVJ based on the clinical features from all age group and gender. They were evaluated on 128 sliced CT scanner. The CVJ anomalies were predominantly seen in the male population. Eight types of anomalies were detected in the study. Most of the anomalies were seen in combination. The most common CVJ anomaly in our study was basilar invagination followed by atlantooccipital assimilation. Most of the cases of basilar invagination were seen in combination with atlantooccipital assimilation and atlantodental dislocation. Maximum cases were detected in the age group of 11 to 20 years. The most common symptom were weakness of extremities, neck pain, parasthesia and tauticalis. The stable shows instances of craniovertible junction anomaly in our study. Maximum is of basilar invagination that is 26.6% followed by atlantooccipital assimilation 23.3%. The least cases were of condylar hypoplasia that is 1.6%. The anomalies were occurring in the combination. Maximum were of basilar invagination and atlantooccipital assimilation. The other associated anomalies were C2C3 fusion, cervical rib, cervical hemivortibram, skeletal deformities in the form of scoliosis and kyphosis. Now the cases. This case demonstrates the basilar invagination. In the image A, the tip of odentoid is seen above macrosline. In B, the tip is above chamberlain line, 11 mm above the chamberlain line and in C, it is 12 mm above the McGregor line. These images demonstrate letebasia. The sagittal reformated images, the welcher basal angle measures 143 degree in image 2A and in image 2B, the clivus canal angle measures 131 degree, producing marked letebasia, leading to compression of the cervical medullary junction. These are sagittal reformated images demonstrating atlantooccipital assimilation. In image 3A, both the anterior and the posterior arch of atlas are not separately visualized from the occiput, suggestive of complete assimilation. Whereas in image 3B, only the posterior arch of the atlas is not visualized separately, which means incomplete assimilation, that is posterior arch assimilation. Now the key feature in identifying gross disruption of the normal alignment of the atlantooccipital joint hinges on atlantodental interval. The atlantodental interval of more than 3 mm in adult and more than 2.5 mm in children is suggestive of atlantoexil instability. This image shows increased atlantodental interval measuring 8.8 mm suggestive of atlantoexil instability. This case demonstrates atlas anomaly. These are axial CT images of craniovertebral junction of a 21-year-old male who presented with complain of syncope. In the image 5A, a well-quarticated midline bony defect is seen in the anterior arch of atlas, suggestive of anterior arch anomaly. In the image 5B, there is a unilateral right-sided defect in the posterior arch of atlas, suggestive of posterior arch anomaly, that is hemiatrys. The image 6A and 6B shows a well-quarticated smooth surface round to oval ossicle superior to the dense and posterior to the anterior arch of atlas, suggestive of oosodentoidum. This image shows coronal reformated images of craniovertebral junction in a case of paraperuses. There is flattening of occipital condyle with widening of atlantooccipital joint axis angle. In our case, it is 130.5 degrees. This is associated with other anomaly as well, that is basilar imagination, vertebral segmentation anomaly and scoliosis. This case had vertebral segmentation anomalies. It is a case of 12-year-old male who presented with tauticolus and paraperuses. In this image, there is complete fusion of C2 to C6 vertebral body and C7, T1 and T2 vertebral body forming block vertebra. Now, few skeletal deformities that were seen in the cases. The image 9A shows focal kyphotic deformity in the cervical spine and image 9B shows a lateral curvature of the cervical dorsal spine with convexity to the right suggestive of scoliosis. The vertebral column develops in six separate but overlapping phases. Any interruption in the developmental process leads to congenital anomaly of craniovertebral junction. Hence, understanding embryology is essential for identifying CVJ anomaly. Craniometry plays a vital role in diagnosing the anomalies and their pre-op evaluation. The congenital anomalies are associated with abnormal physical appearance such as head tilt, short neck, low hairline and limited neck movements. The CVJ anomalies constitute an important group of treatable neurological disorders. Thus, it is essential to make a precise diagnosis of CVJ abnormalities, classify them as this information ultimately determines the management of such abnormalities, prognosis and quality of life. Multi-detector CT is the investigation of choice for diagnosing and planning the management. However, dynamic CT can provide additional useful information to diagnose CVJ abnormalities. CT complemented with MRI is recommended for associated neurological involvement. These are my references. Thank you.