Muscular and brain cysticercosis

A previously healthy 45-year-old woman presented with seizures. Computed tomography and subsequent magnetic resonance imaging (MRI) revealed calcified brain lesions (Figure 1).

MRI revealed multiple cerebral ring-enhancing lesions with cystic components, a scolex, and vasogenic edema (Figure 1).

FIGURE 1:
(A) Axial computed tomography reveals multiple sub-centimeter calcified lesions (arrows) predominantly throughout the supratentorial brain. (B) Axial susceptibility-weighted imaging (SWI) demonstrates multiple round hypointense foci, consistent with calcifications (arrows). (C) Axial contrast-enhanced T1-weighted image (WI) reveals a cystic ring-enhancing lesion (arrow) with perilesional edema in the left putamen. (D) Axial diffusion-weighed imaging (b=1000) reveals a hyperintense eccentric dot (scolex, arrow) indicative of neurocysticercosis in the colloidal vesicular stage.

Fast imaging, employing a steady-state acquisition MRI sequence also revealed lesions in the fourth ventricle, indicating the racemose form of extra-parenchymal neurocysticercosis (NCC) (Figure 2). The racemose form, which requires prolonged treatment, is associated with increased morbidity and mortality and may lead to cerebrovascular complications^1,2. NCC was considered the cause for the epilepsy, being among the most common causes of structural epilepsy³.

FIGURE 2:
Sagittal and axial fast imaging, employing steady-state acquisition images (A and B) demonstrate an isointense lesion in the lower portion of the roof of the fourth ventricle (arrow). Steady-state free precession sequences help identify intraventricular cysts.

Rice-like ovoid calcifications resembling a starry sky were identified in the muscles (Figure 3), suggestive of cysticercosis⁴. The muscular form of cysticercosis is generally asymptomatic. However, three distinct types of manifestations may be observed: the myalgic, myopathic type; the nodular or mass-like type; and the rare pseudohypertrophy type⁵.

FIGURE 3:
Coronal (A and B) non-contrast-enhanced computed tomography with maximum intensity projection reveals multiple elongated and oval-shaped calcified lesions within the hip and thigh muscles.

If rice- or starry sky-like muscular calcifications are detected, cysticercosis must be suspected⁶. Even in patients without systemic or neurological manifestations, this finding is indicative of this diagnosis.

This case highlights the association of NCC with the muscular form of cysticercosis and its peculiar imaging findings in a patient with epilepsy beginning in adult life.

ACKNOWLEDGMENTS

We offer our deepest thanks to the institutions that provided technical support for the development and implementation of this study.

REFERENCES

• ¹
  Yacoub VRD, Ramos MC, Reis F. High-resolution vessel wall magnetic resonance imaging for the diagnosis of neurocysticercosis vasculitis. Rev Soc Bras Med Trop. 2022;55:e0203.
• ²
  Garcia HH, Gonzalez AE, Gilman RH. Taenia solium cysticercosis and its impact in neurological disease. Clin Microbiol Rev. 2020;33(3):e00085-19.
• ³
  Miyoshi IC, de Toledo AHN, Pereira FV, Villarinho LL, Dalaqua M, de Ávila Duarte J, et al. Infectious Myelitis. Semin Ultrasound CT MR. 2023;44(5):424-35.
• ⁴
  Yamashita P, Kelsey J, Hendeerson SO. Subcutaneous cysticercosis [clinical communications]. J Emerg Med. 1998;16(4):583-6.
• ⁵
  Asrani A, Morani A. Primary sonographic diagnosis of disseminated muscular cysticercosis. J Ultrasound Med. 2004;23(9):1245-8.
• ⁶
  Liu H, Juan YH, Wang W, Liang C, Zhou H, Ghonge NP, et al. Intramuscular cysticercosis: starry sky appearance. QJM. 2014;107(6):459-61.

• Financial Support: There are no funding sources.

Publication Dates

• Publication in this collection
  20 Oct 2023
• Date of issue
  2023

History

• Received
  12 Sept 2023
• Accepted
  22 Sept 2023