51  yr old male presented with abnormal behaviour.

51 yr old male presented with abnormal behaviour.

  • 51 yr old male presented with abnormal behaviour.
  • A. Hydrocephalus with transependymal seepage of CSF.
  • B. Parenchymal calcification.
  • C and D. Multiple multiloculated CSF intensity lesions in bilateral sylvian fissures and suprasellar cisterns with no post contrast enhancement.

RACEMOSE NEUROCYSTCERCOSIS

DISCUSSION

Racemose neurocysticercosis

  • Invasive parasitic infection of the central nervous system caused by the larval stage of the tapeworm Taenia solium.
  • Most frequent cause of acquired epilepsy in the developing countries.
  • Parasitic infestation is endemic to South and Central America, Southeast Asia, China, and Sub-Saharan Africa.
  • Depending on the site of involvement, they are classified into intraparenchymal, extra parenchymal (subarachnoid-cisternal, meningeal, intraventricular) and mixed types.
  • The racemose variant of extraparenchymal NCC  is characterized by the presence of multilobulated confluent cysts within the basal subarachnoid space that appear “grape-like” both radiographically and pathologically.
  • Clinical presentation can be variable.

Clinical manifestations of Racemose NCC

RADIOLOGICAL INVESTIGATIONS

Computed tomography (CT)

  • Sensitivity and specificity of more than 95% in the diagnosis of the parenchymatous form of neurocysticercosis.
  • Lower sensitivity and specificity for diagnosing the ventricular and cisternal forms.
  • Helpful in detecting calcifications.

MRI

  • The cisternal or ventricular forms of neurocysticercosis are readily visualized in MRI.
  • The cysts are usually larger than in the parenchymal forms and have a multilocular appearance, tend to displace neighboring structures, and behave as lesions with a mass effect.
  • The signal intensity is similar to that of the cerebrospinal fluid.
  • Normally do not show significant contrast enhancement; may show peripheral enhancement
  • Cysticerci usually do not contain scolices. If a scolex is seen, it is almost diagnostic/pathognomonic.
  • Conventional MR sequences such as T1- and T2-weighted images and fluid-attenuated inversion recovery images may miss intraventricular/cisternal neurocysticercosis cysts.
  • Three-dimensional (3D), very heavily T2-weighted sequences, such as constructive interference in steady state or fast imaging employing steady-state acquisition, are good sequences for evaluating intraventricular cysts.
  • Another MR sequence that is also useful is the 3D spoiled gradient recalled echo sequence, which provides T1 information.

DIFFERENTIAL DIAGNOSIS

  • Arachnoid cysts
  • Porencephaly
  • Hydatid disease
  • Cystic astrocytoma
  • Colloid cyst of third ventricle

Diagnosis

  • Positive hydatid serology will further be supporting evidence.
  • Serological tests (enzyme-linked immunoelectrotransfer blot assay, enzyme-linked immunosorbent assay) that detect anticysticercal antibodies in serum or CSF inherently lack specificity or sensitivity, thereby precluding their reliability in isolation.
  • MRI is the primary diagnostic modality used for the detection of cysticercus lesions and their secondary complications.

Treatment

  • Medical management with cysticidal agents, corticosteroids, and antiepileptic drugs
  • Surgical management to remove the cyst or to insert a shunt to treat hydrocephalus.

REFERENCES

  • Mahale RR, Mehta A, Rangasetty S. Extraparenchymal (Racemose) Neurocysticercosis and Its Multitude Manifestations: A Comprehensive Review. J Clin Neurol. 2015 Jul;11(3):203-211. https://doi.org/10.3988/jcn.2015.11.3.203
  • Sharma S, Singh A, Mani VE, Mishra SC, Chaturvedi P, Jain S, Kumar S, Jain N. Racemose neurocysticercosis: a case series. BJR Case Rep. 2024 Jan 19;10(1):uaae001. doi: 10.1093/bjrcr/uaae001. PMID: 38352260; PMCID: PMC10860505.
  • Krupa K, Krupa K, Pisculli ML, Athas DM, Farrell CJ. Racemose neurocysticercosis. Surg Neurol Int. 2016 Feb 5;7:12. doi: 10.4103/2152-7806.175881. PMID: 26958418; PMCID: PMC4766808.
  • https://www.ajnr.org/ajnr-case-collections-diagnosis/racemose-neurocysticercosis.

Dr. HARSHA CHADAGA
SENIOR CONSULTANT RADIOLOGIST AND HOD OF RADIOLOGY
MANIPAL HOSPITAL , YESHWANTHPUR, BENGALURU

Dr. VINEETH BABY
FELLOW IN CROSS SECTIONAL IMAGING
MANIPAL HOSPITAL , YESHWANTHPUR, BENGALURU