Sniya Valsa Sudhakar

White Matter Anatomy: What the Radiologist Needs to Know

Diffusion tensor imaging (DTI) has allowed in vivo demonstration of axonal architecture and connectivity. This technique has set the stage for numerous studies on normal and abnormal connectivity and their role in developmental and acquired disorders. Referencing established white matter anatomy, DTI atlases, and neuroanatomical descriptions, this article summarizes the major white matter anatomy and related structures relevant to the clinical neuroradiologist in daily practice.

Calcifying fibrous tumour: an unusual omental lesion

Calcifying fibrous tumour (CFT) is a recently described distinct clinicopathological entity characterized by calcifying lesions usually occurring in soft tissue of the extremities, trunk, axilla, pleura, mediastinum and peritoneum of children and adults. Most reported cases involving the peritoneum have been in adults. We present the imaging, surgical and pathology findings of CFT in a 7-year-old child who presented with an incidental finding of a large omental mass.

Beta Propellar Protein-Associated Neurodegeneration: A Rare Cause of Infantile Autistic Regression and Intracranial Calcification.

Neurodegeneration with brain iron accumulation (NBIA) is a heterogeneous group of single gene disorders with distinguished clinical phenotypes and definitive imaging findings. Beta propeller protein-associated neurodegeneration (BPAN) is a subentity of NBIA with X linked dominant inheritance. In this report, we describe a girl with autistic regression, seizures, intracranial calcification, iron accumulation in substantia nigra, and globi pallidi, and diagnosis of BPAN was established based on the identification of previously described disease causing variant in WD repeat domain 45 (WDR45) gene encoding for β propeller protein. This is the first genetically proven case from India. BPAN is an underrecognized disorder and must be considered as a differential diagnosis in children with atypical Rett features and should be enlisted among the causes for autistic regression and intracranial calcification. Pediatricians must be aware of this rare entity for establishing early diagnosis, prognostication, and genetic counseling. Treatment is usually supportive. More research is needed to explore drugs in the management of BPAN that can facilitate the autophagy and promotes cytoprotection.

Eye of tiger sign mimic in an adolescent boy with mitochondrial membrane protein associated neurodegeneration (MPAN).

Neurodegeneration with brain iron accumulation (NBIA) refers to an inherited heterogeneous group of disorders pathologically characterized by focal brain iron deposition. Clinical phenotype, imaging findings and genotype are variable among the different types of this disorder. In this case report, we describe the imaging finding of an adolescent boy with mitochondrial membrane protein associated neurodegeneration (MPAN), a subentity of NBIA. Magnetic resonance imaging of brain revealed hypointensity of globi pallidi with medial medullary lamina appearing as a hyperintense streak in T2 weighted images. Mild cerebellar atrophy in T2 weighted images and blooming of substantia nigra and globi pallidi in susceptibility weighted images were also observed. Imaging findings in patients with MPAN mimics the eye of tiger appearance in patients with pantothenate kinase associated neurodegeneration. Classical phenotype and eye of tiger sign mimic in imaging of patients with NBIA should raise the suspect for MPAN. Genetic studies helps in the confirmation of diagnosis of this neurodegenerative disorder.

Asymptomatic gastrosplenic fistula in a patient with marginal zonal lymphoma transformed to diffuse large B cell lymphoma—a case report and review of literature

Dear Editor, Gastrosplenic fistula (GSF) is a rare and potentially fatal complication of lymphoma which can occur both spontaneously and after chemotherapy [1–4]. Here, we report a patient with diffuse large B cell lymphoma (DLBCL) who was incidentally diagnosed with a GSF on interim PET-CT after three cycles of chemotherapy. A 57-year-old gentleman, who had no significant past history, presented with intermittent low-grade fever and occasional cough of 2 weeks duration. Clinical examination was insignificant except for a single right axillary lymph node (1 cm×1 cm) and palpable spleen. Imaging studies revealed multiple intra-abdominal lymphadenopathy and splenomegaly of 15 cm with two well-defined hypoechoic lesions. He underwent a right axillary lymph node biopsy which was consistent with marginal zone lymphoma (low MIB-1 proliferation index—20 %). He was started on cyclophosphamide and prednisolone, in view of a low-grade lymphoma, as therapy, and was on regular follow up. Two years after the initial diagnosis, he presented with complaints of weight loss and easy fatigability. Clinical evaluation revealed bilateral inguinal lymphadenopathy and hepatosplenomegaly. Repeat imaging of the abdomen showed multiple intra-abdominal lymph nodes and increase in splenomegaly with welldefined heterogeneous lesion measuring 9×8 cm. A new heterogeneous lesion in the left lobe of the liver measuring 8.5×8 cm was noted. High grade transformation of the initial low-grade lymphoma was suspected and an ultrasoundguided biopsy of the para-aortic lymph node revealed DLBCL with aMIB-1 proliferation index of 60%. Hewas subsequently started on R-CHOP 21 chemotherapy which he tolerated well. Interim PET-CT done after three cycles to assess the disease status revealed persistent splenomegaly with two focal lesions, of which the larger lesion had eroded the stomach wall forming a GSF with surrounding stomach wall thickening. There was persistence of the hepatic lesion and intraabdominal lymphadenopathy. The PET confirmed the GSF to be metabolically active (Fig. 1). He had no abdominal pain or symptoms suggestive of gastrointestinal bleeding and stool was negative for occult blood. Endoscopy of the upper gastrointestinal (GI) tract revealed a big excavated ulcer with erythematous, elevated, and irregular margins in the gastric fundus with an opening noted at one edge of the ulcer with food particles in it. Biopsy from the margins of the ulcer showed features ofHelicobacter pylori associated gastritis with extensive ulceration. The patient was started on triple drug therapy for H. pylori . He remained completely asymptomatic for his incidentally detected GSF. However, in view of an impending bleed, surgery consultation was sought and planned to proceed with a surgical correction, involving a sleeve gastrectomy. However, the patient refused any surgical intervention andwas lost to follow up thereafter. GSF has been described in gastric adenocarcinoma [5], Crohn’s disease [6], splenic abscess [7], and trauma. GSF has also been described in connection to both Hodgkin and non-Hodgkin lymphomas [1], developing spontaneously or after chemotherapy. Splenic lymphomas have a high propensity for invasion of adjacent structures. In one series of ten patients with splenic DLBCL [8], nine showed breach of the splenic capsule and seven invading the structures, of which four involved the stomach. Colonosplenic fistulas have also been described in context to lymphoma [9]. Gastric MALTomas resulting in gastrosplenic, gastrocolic, and J. Senapati (*) :A. J. Devasia :A. Viswabandya Department of Clinical Haematology, Christian Medical College and Hospital, Vellore 632004, Tamil Nadu, India e-mail: jsalwayswins@gmail.com

Imaging in Pediatric Demyelinating and Inflammatory Diseases of the Brain- Part 1.

Imaging plays an important role in the diagnosis, management, prognostication and follow up of pediatric demyelinating and inflammatory diseases of the brain and forms an integral part of the diagnostic criteria. Conventional and advanced MR imaging is the first and only reliable imaging modality. This article reviews the typical and atypical imaging features of common and some uncommon demyelinating and inflammatory diseases with emphasis on the criteria for categorization. Imaging protocols and the role of advanced imaging techniques are also covered appropriately.

Clinical, imaging and histopathological features of isolated CNS lymphomatoid granulomatosis.

Lymphomatoid granulomatosis is a rare systemic angiocentric/angiodestructive, B cell lymphoproliferative disorder. Central nervous system involvement occurs as part of systemic disease. Isolated central nervous system disease is rare with only few case reports. A 53-year-old male presented with progressive cognitive decline, extrapyramidal features, and altered sensorium with seizures over the last 4 years. His magnetic resonance imaging (MRI) of brain showed multiple small enhancing nodules in subependymal/ependymal regions and along the vessels. Brain biopsy showed atypical lymphohistiocytic infiltrate suggestive of lymphomatoid granulomatosis. There was no evidence of systemic disease; thus, isolated central nervous system lymphomatoid granulomatosis was diagnosed.

Acute necrotising encephalopathy in a child with H1N1 influenza infection: a clinicoradiological diagnosis and follow-up.

Acute necrotising encephalopathy of childhood (ANEC) is a fulminant disorder with rapid progressive encephalopathy, seizures and poor outcome. It has been reported in association with various viral infections. We describe the clinicoradiological findings and short-term follow-up in a child with H1N1 influenza-associated ANEC. Laminar, target or tricolour pattern of involvement of the thalami was seen on apparent diffusion coefficient images. Our patient had significant morbidity at discharge despite early diagnosis and management with oseltamivir and immunoglobulin. Repeat imaging after 3 months had shown significant resolution of thalamic swelling, but there was persistence of cytotoxic oedema involving bilateral thalami. She was pulsed with intravenous steroids and maintained on a tapering schedule of oral steroids. This report emphasises the need for a high index of suspicion to establish early diagnosis, promotion of widespread immunisation strategies to prevent influenza outbreak, and more research to establish standard treatment protocols for this under-recognised entity.

Cerebrotendinous xanthomatosis: Possibility of founder mutation in CYP27A1 gene (c.526delG) in Eastern Indian and Surinamese population

Cerebrotendinous xanthomatosis is a lipid storage disease characterized by diarrhea, cataract, tendon xanthoma and neurological regression if untreated. CYP27A1 is the only gene in which mutations are known to cause Cerebrotendinous xanthomatosis. We report two Indian families from different regions of India who underwent molecular testing of CYP27A1. The first family from Eastern India consisting of two affected individuals was found to have the c.526delG homozygous mutation in exon 3, previously reported from our laboratory, also in a patient from Eastern India. However the second affected individual from Southern India that we studied and two previously reported cases from Northern India have different mutations. Interestingly the only previous report of c.526delG mutation was in a Surinamese individual from the Netherlands. To date most of the pathogenic mutations for Cerebrotendinous xanthomatosis have been confined to single population except for R362C mutation which was reported from the Netherlands and the USA (Black). To our knowledge this is the second causal mutation for Cerebrotendinous xanthomatosis which has been reported in two different populations. As human trading was prevalent from Eastern India to Surinam by the Dutch settlers this mutation might suggest a common founder mutation in these populations.

Hypomyelination, Hypodontia, Hypogonadotropic Hypogonadism (4H) Syndrome With Vertebral Anomalies: A Novel Association.

Hypomyelination, hypodontia, hypogonadotropic hypogonadism (4H) syndrome is a rare hypomyelination disorder with around 40 cases reported worldwide. Children with hypomyelination, hypodontia, hypogonadotropic hypogonadism syndrome present with varying degrees of developmental delay with a spastic ataxic syndrome with delayed eruption of teeth along with disruption in the eruption sequence, hypogonadotropic hypogonadism, and a fluctuating clinical course with intercurrent infections and varying periods of stability. The disorder is caused by mutations in POL3A and POL3B genes and is collectively termed as pol III–related leukodystrophies. Here we describe 2 children with hypomyelination, hypodontia, hypogonadotropic, hypogonadism syndrome and the association of multiple vertebral fusion anomalies in one of them, which has not been previously described in the literature. We conclude that the spectrum of the disorder is not limited to brain parenchyma alone and involves all the structures arising from neural ectoderm, and this needs further research.