Magnetic resonance imaging findings in central nervous system tuberculosis: A pictorial review.

Central nervous system (CNS) tuberculosis is a post-primary form of tuberculosis. It has high mortality and morbidity rates despite early diagnosis and treatment. CNS tuberculosis can manifest as subacute/chronic meningitis, parenchymal tuberculous lesions, and spinal tuberculosis. Hematogenous spread of tuberculous bacilli to the brain results in the development of so called "rich foci" on the pial surface, ependyma, and grey-white matter junction. Rupture of these "rich foci" into the subarachnoid space triggers an intense granulomatous inflammatory reaction. Tuberculous meningitis can manifest as leptomeningitis or pachymeningitis. Intracranial parenchymal tuberculous lesions may present as tuberculoma, tuberculous abscess, cerebritis, rhombencephalitis, and encephalopathy, with atypical presentations not uncommon. Complications of CNS tuberculosis encompass hydrocephalus, syrinx formation, vasculitis, infarcts, neuritis, and enduring neurological deficits. Post-contrast 3D fluid-attenuated inversion recovery (FLAIR) and post-contrast T1 spin-echo sequences excel in detecting tuberculous meningitis compared to other conventional magnetic resonance imaging (MRI) sequences. In proton magnetic resonance spectroscopy (PMRS), the presence of a lipid peak at 1.3 ppm is indicative of tuberculous lesions. Magnetization transfer (MT) imaging enhances the detection of tuberculous lesions, as the magnetization transfer ratio (MTR) of tuberculous pathologies, owing to their high lipid content, is lower than that in bacterial or fungal pathologies and higher than that in viral pathologies. This review article delves into the various typical and atypical imaging presentations of CNS tuberculosis in MRI, along with recent advances in imaging techniques.

Evaluation of variations of optic nerve course in relation to posterior paranasal sinuses in MDCT in a tertiary care center of Nepal: a retrospective cross-section study.

Background: The proximity of optic nerves to the posterior paranasal sinuses (PNS) is a critical consideration in preventing optic nerve injuries during functional endoscopic sinus surgery. Methods: A retrospective cross-sectional study was conducted on 367 patients aged 13 years and above. Four radiologists, each with 2-6 years of experience, evaluated computed tomography scans of the PNS and the head of these patients. The optic nerves were classified into four types based on DeLano's classification, and their respective prevalence rates were determined. Additionally, the prevalence of optic nerve dehiscence and pneumatization of the anterior clinoid process was assessed. Results: A total of 734 optic nerves were evaluated and categorized into four groups as per DeLano's classification. The most common type was classified as type 1 optic nerve, representing 65.4% of all optic nerves. Types 2, 3, and 4 optic nerves accounted for 16.9, 8.6, and 9.1%, respectively. The prevalence rates of type 1, type 2, type 3, and type 4 optic nerves were 76.6, 24.5, 12.3, and 14.4%, respectively. Optic nerve dehiscence was observed in 14.3% of cases, with a prevalence of 21.2% in the study. Type 3 optic nerves were most commonly associated with dehiscence, with 49.2% of them showing dehiscence in their course through the ethmoid or sphenoid sinus. The prevalence of pneumatization of the anterior clinoid process in the study population was 28.3%, with type 3 optic nerves being the most frequently associated. Conclusion: An understanding of the relationship between optic nerves and posterior PNS, as well as awareness of optic nerve dehiscence, is essential in preventing injuries during sinus surgeries. Type 1 optic nerve predominates among Nepalese patients visiting our hospital.

Delayed presentation of congenital sigmoid colon stenosis: a rare entity.

Congenital sigmoid colon stenosis is a rare entity that can mimic Hirschsprung disease. Presentation of congenital colon stenosis is usually within first few weeks of life. Our case presented with features of distal bowel obstruction at 2 years of age with the history of chronic constipation and progressive abdominal distention from first week of life and bilious vomiting for the last 1 week. Clinical diagnosis of Hirschsprung disease was made. Contrast enhanced CT abdomen showed bowel obstruction with transition point at the level of proximal sigmoid colon. There was a short segment stenosis at the level of proximal sigmoid colon. Contrast enema showed stenosis at proximal sigmoid colon. The bowel distal to stenosis was normal in calibre. Similar findings were seen during surgery. Mesocolon was present in stenosed segment of the bowel. The resected stenotic segment showed adequate ganglion cells in histopathology.

Hashimoto thyroiditis in a lingual thyroid: An interesting case.

Key Clinical Message: Whenever an enlarging mass is seen in throat, possibility of lingual thyroid should be considered. Thyroid function test should be done whenever ectopic thyroid is detected. Imaging (ultrasonography or Tc-99m scintigraphy) is adequate for diagnosis. Conservative treatment with levothyroxine helps in reducing size of lingual thyroid. Abstract: Hashimoto thyroiditis in lingual thyroid results in enlargement of the thyroid gland and oropharyngeal symptoms. Suppression therapy with levothyroxine results in reduction in size of the gland. We present an interesting case of Hashimoto disease in an adolescent female presenting as oropharyngeal mass.

Von Hippel Lindau Disease with central nervous system and multiple visceral manifestations: A case report.

Von Hippel-Lindau (VHL) disease is an autosomal-dominant syndrome caused by mutations in the VHL gene, located on the short arm of chromosome 3. Patients with VHL are likely to manifest with a spectrum of multiple benign and malignant tumors involving various organ systems. We present a case of a 28-year-old female without a remarkable family history who presented with complaints of hematuria and abdominal discomfort. Initial laboratory investigations confirmed hematuria. Subsequent abdominal computed tomography scan revealed heterogeneous enhancing solid mass in bilateral kidneys, avidly enhancing mass in the right adrenal gland, bilateral simple renal cortical cysts, and a pancreatic cyst. With a provisional diagnosis of VHL disease, an MRI of the brain and spine was performed, which showed the presence of a cerebellar hemangioblastoma. Her catecholamine and vanillylmandelic acid levels were in the normal range not in line with pheochromocytoma. The patient then underwent bilateral partial renal nephrectomy and right adrenalectomy. Histopathologic examination reported clear renal cell carcinoma and pheochromocytoma of the right adrenal gland mass. Molecular genetic testing confirmed the presence of VHL disease.

Pituitary stalk interruption syndrome: A case report.

Pituitary stalk interruption syndrome (PSIS) is a rare congenital abnormality. It comprises the triad of thin or interrupted pituitary stalk, aplasia or hypoplasia of anterior pituitary gland, and absent or ectopic posterior pituitary gland. The patient usually presents with a spectrum of symptoms predominantly secondary to anterior pituitary hormonal deficiency. The etiology of this syndrome is not well-established but the genetic cause is considered to be the most common etiology. Early diagnosis is crucial in preventing and reducing morbidity. The prognosis is good if the condition is diagnosed early and the hormonal therapy is started promptly. The diagnosis of PSIS is primarily based on magnetic resonance imaging (MRI) findings.

Acute hydrocephalus caused by colloid cyst of third ventricle: A case report.

Colloid cysts (CCs) of third ventricle are rare benign lesions. They present with acute hydrocephalus and its sequalae like brain herniation, infarcts resulting even death in otherwise healthy individual. We present a case of an acute hydrocephalus caused by CC of third ventricle. A middle age male was airlifted from a remote district of Nepal to our hospital with no accompanying doctor. The patient had headache, multiple episodes of vomiting, abnormal body movement, and loss of consciousness for 24 hours. On examination, vitals were stable; the Glasgow Coma Scale (GCS) score was 7. The patient was intubated in emergency and an MRI brain was done. MRI showed an obstructive lesion in third ventricle with features consistent with CC and an active hydrocephalus. There were multifocal infarcts in the bilateral cerebrum, left part of mid brain and pons, left thalamus and left superior cerebellum. We inserted external ventricular drainage in emergency operation theatre within hours and endoscopic excision of the lesion was done on the next day. In histopathology, the lesion was confirmed to be a CC.

Ischemic Portal Venous Gas and Pneumatosis Intestinalis Managed Conservatively in a Patient with Rheumatic Heart Disease and Warfarin Induced Coagulopathy: A Case Report.

Mesenteric ischemia is a surgical emergency. The presence of hepatic portal venous gas and pneumatosis intestinalis is a frequent finding in computed tomography. Not all hepatic portal venous gas and pneumatosis intestinalis are due to mesenteric ischemia. A 70-year-old female, with a known case of diabetes mellitus, rheumatic heart disease and atrial fibrillation under warfarin presented with diffuse abdominal pain, multiple episodes of vomiting and ecchymosis in bilateral flanks. Evaluation of the coagulation profile suggested warfarin-induced coagulopathy. Portal venous gas was detected during an ultrasound examination. Subsequent contrast-enhanced computed tomography abdomen showed hepatic portal venous gas, pneumatosis intestinalis, paucity of branches of the ileocolic artery, and reduced enhancement of caecum and ascending colon. Mild ascites were present in the pelvis. Arterial blood gas analysis revealed compensated metabolic acidosis. The patient was managed conservatively and discharged after nine days of hospital admission. Conservative approach can be considered for suspected mesenteric ischemia in surgically unfit candidates. Keywords: case reports; mesenteric ischemia; portal vein; rheumatic heart disease; warfarin.

Changes in liver morphology in patients with extrahepatic portal venous obstruction: a retrospective magnetic resonance imaging study.

OBJECTIVE: To investigate the liver parenchymal changes on MRI in patients with extrahepatic portal venous obstruction (EHPVO). METHODS: This was a retrospective evaluation of the MRI studies in patients with EHPVO between January 2016 and April 2018. The diagnosis of EHPVO in each case had been established on the basis of clinical and Doppler parameters. Following findings were recorded on MRI: liver size; outline; overall volume redistribution; volume redistribution of caudate, right and left lobes; signal heterogeneity, intrahepatic biliary radicle dilatation, focal liver lesions, gallstones and ascites. RESULTS: A total of 164 MRI studies were evaluated. Median age was 27 years (range, 6-70). There were 90 (54.9%) males and 74 (45.1%) females. The median liver size was 14 cm (range 5-17). The median spleen size was 15.9 cm (range, 6-28). A spleen size ≥12 cm was seen in 136 (82.9%) patients. The liver outline was nodular in 32 (19.5%) patients. Volume redistribution was seen in 63 (38.4%) patients. Caudate lobe hypertrophy was seen in 49 (29.9%) patients. Right lobe atrophy and hypertrophy was seen in 4 (2.4%) and 1 (0.6%) patients respectively. Left lobe atrophy and hypertrophy was seen in 15 (9.1%) and 10 (6.1%) patients respectively. 30 MRI (18.3%) showed heterogeneous signal intensity. Focal lesions were seen in 22 (13.4%) patients. Intrahepatic biliary radicle dilatation, gallstones and ascites were seen in 120 (73.2%), 54 (32.9%) and 26 (15.9%) patients respectively. CONCLUSION: Liver morphological changes are common in EHPVO. ADVANCES IN KNOWLEDGE: The morphological changes in liver in patients with EHPVO have not been described previously. This information will prevent misdiagnosis of this condition as cirrhosis.