1. The document discusses the diagnosis and management of neurocysticercosis (NCC), including laboratory findings, immunological diagnosis, neuroimaging features, and treatment approaches.
2. Key neuroimaging findings for NCC include cystic lesions in the brain parenchyma, ventricles, and subarachnoid space that vary in appearance depending on the stage of cyst evolution.
3. Treatment involves symptomatic therapy with anti-seizure drugs, use of cysticidal drugs like albendazole and praziquantel to destroy cysts, and occasionally surgery for lesions in certain locations.
2. Laboratory findings
• Peripheral eosinophilia - up to 37% of cases
• Ventricular NCC – CSF
• Moderate mononuclear pleocytosis (cell counts rarely exceeding 300
per mm3),
• Moderate increase in CSF protein (50–300 mg/dL)
• CSF glucose levels are usually normal
• Hypoglycorrhachia - poor prognosis
3. Immunologic Diagnosis
• Assess prevalence of cysticercosis in populations
• Exclude or confirm diagnosis – neuroimaging findings inconclusive
• Enzyme-linked immunoelectrotransfer blot assay (EITB)
• detects antibodies to T. solium glycoprotein antigen in serum - lentil
lectin purified glycoprotein antigens (LLGP)
• Only reliable serologic test – specificity up to 100% and sensitivity of
up to 98% for patients with two or more lesions
4. • Major weakness - high rate of false-negative results (up to 50%) – SCG
• Poor sensitivity - calcified cysticerci
• In hospital-based series of SCG, however, the yield of the EITB was
considerably lower, 20% – 80%
5. Neuroimaging
• Objective evidence on the number and topography of lesions
• Burden of infection
• Stage of involution
• Degree of the host’s inflammatory reaction
• MRI - imaging modality of choice - cystic lesions located in the
ventricular system, the brainstem, subarachnoid space
• CT - best screening neuroimaging – suspected NCC - parenchymal
brain calcifications may be sole evidence of the disease
6. PARENCHYMAL
NEUROCYSTICERCOSIS
• Depend on the stage of involution
• Vesicular cysticerci
• small and rounded cysts, well demarcated
• eccentric hyperdense nodule in the interior - scolex
• pathognomonic “hole-with-dot” appearance
• no edema/contrast enhancement
• heavy nonencephalitic form of neurocysticercosis - brain looks like a
‘‘Swiss cheese /Starry sky ,’’ - another imaging finding that is
pathognomonic
7.
8.
9. • Colloidal cysticerci
• ill-defined lesions surrounded by edema
• ring pattern of enhancement
• Scolex - not usually visualized
• diagnostic challenge - tuberculomas, toxoplasma, brain abscesses,
primary or metastatic brain tumors – similar neuroimaging findings
• DWI and ADC maps facilitates the diagnosis - recognition of the scolex
10.
11. • Cysticercotic encephalitis - severe form of the disease
• diffuse brain edema and collapse of the ventricular system without
midline shift
• multiple small ring-like or nodular lesions appear disseminated within
the brain parenchyma
12.
13. • Granular cysticerci / cysticercus granuloma
• CT - discretely hyperdense nodular-enhancing lesion + surrounding
edema
• MRI – hypo onT1- and T2, surrounded by hyperintense rim -
representing gliosis
• Thicker ring or disk enhancement
14.
15. • Calcified (dead) cysticerci
• CT - small hyperdense nodules without perilesional edema or
abnormal enhancement
• Sensitivity of conventional MRI - poor, SWI may enhance the
identification of calcifications
16.
17. Solitary cysticercus granuloma
• Contrast CT - enhancing ring- or disk-shaped lesion
• usually less than 20 mm in diameter
• surrounded by a variable amount of perifocal edema
• eccentric scolex is frequently seen within the ring lesion
• Seen throughout the cerebral hemispheres, parietal and frontal lobes
- most frequent
• Plain CT - irregular white matter hypodensity due to vasogenic edema
• tiny speck of calcification may be seen within the area of hypodensity
18. Radiologic features consistent with a diagnosis of SCG
• A diagnostic and therapeutic scheme for a solitary cysticercus granuloma G. Singh, V. Rajshekhar,
J.M.K. Murthy, et al. Neurology 2010;75;2236
19.
20. DD of SCG
• small intracranial tuberculoma
• Tuberculomas - greater than 20 mm in size, irregular in outline, may
be associated with a midline shift
• Cysticercus granulomas - less than 20 mm in size, regular in outline,
not associated with a midline shift
• Visualization of the scolex as eccentric dot – characteristic, appears as
a hyperintense nodule within the live cyst, this gives a characteristic
hole-with dot appearance
21. • Earlier, ‘target sign’ (central nidus of calcification surrounded by a
ring of enhancement) was pathognomonic for tuberculoma
• In HIV - imaging picture resembling ‘the eccentric target sign’ -
suggestive of toxoplasmosis, eccentric core is produced by the leash
of inflamed leaky vessels entering through a sulcus into the lesion
• Mets - target’ lesion with a central core of calcification
• ‘target sign’ - nonspecific neuroimaging finding and is not specific for
NCC
22. • MRS in cysticercosis - elevated levels of lactate, alanine, succinate
and choline and reduced levels of N-acetyl aspartate and creatine.
• MRS in tuberculoma shows a high peak of lipids, more choline and
less N-acetylaspartate and creatine.
• The choline/creatine ratio was greater than 1 in all tuberculomas
23.
24. Radiologic resolution of SCG
• Majority - resolve by 1 year
• Natural historymay take one of the following paths:
• lesion may completely resolve
• lesion may resolve by leaving behind a punctuate calcific residue
25. Neuroimaging - Recommendations
• The initial imaging evaluation of SCG may be either contrast CT or
MRI
• Once CT demonstrates a single enhancing lesion consistent with a
diagnosis of SCG, further evaluation with MRI may not be required
•A diagnostic and therapeutic scheme for a solitary cysticercus granuloma G. Singh, V. Rajshekhar,
J.M.K. Murthy, et al. Neurology 2010;75;2236
26. Appropriate timing and modality of
follow-up imaging
• Follow-up imaging (either contrast-enhanced CT or MRI) should be
undertaken at 6 months following initial symptomatic presentation in
all individuals with SCG
• Earlier CT might be useful in order to identify those lesions that
enlarge or change morphology - suggesting an alternative etiology
(e.g., neoplasm, tuberculoma, or fungal granuloma)
27. SUBARACHNOID
NEUROCYSTICERCOSIS
• Most common neuroimaging finding - hydrocephalus
• inflammatory occlusion of Luschka and Magendie foramina
• fibrous arachnoiditis - responsible for hydrocephalus, seen as
abnormal basal leptomeningeal enhancement
• Cystic subarachnoid lesions
• Small - located within cortical sulci,
• Large - Sylvian fissure or within the basal cisterns
• Multilobulated appearance - racemose form, displace neighboring
structures, and behave as SOL
28.
29. VENTRICULAR
NEUROCYSTICERCOSIS
• CT – Ventricular cysts are isodense with CSF; cannot be directly
visualized
• Appear as hypodense lesions that distort the ventricular system,
causing asymmetric obstructive hydrocephalus
• MRI - ventricular cysts are readily visualized because the signal
properties of the cystic fluid or the scolex differ from those of the CSF
• Cyst mobility within the ventricular cavities in response to
movements of the head - ventricular migration sign
30.
31. SPINAL CORD
NEUROCYSTICERCOSIS
• MRI - imaging modality of choice - suspected cysticercosis of the
spinal cord or the spinal subarachnoid space
• Intramedullary cysticerci - rounded or septated lesions that may have
an eccentric hyperintense nodule representing the scolex
• If scolex is not identified - difficult to differentiate from spinal tumors
• Leptomeningeal cysts - freely mobile within the spinal subarachnoid
space and change their position according to movements of the
patient on the exploration table
32.
33. Diagnostic criteria
• Diagnosis - challenge in many patients
• Clinical manifestations are nonspecific
• Neuroimaging findings are most often not pathognomonic
• Serologic tests - relatively poor specificity and sensitivity
• Histologic demonstration of the parasite is not possible in most cases
• Diagnostic criteria based on the objective evaluation of clinical,
radiologic, immunologic and epidemiologic data has been proposed
34. Diagnostic Criteria for Neurocysticercosis
• Del Brutto OH, Rajshekhar V, White AC Jr et al. (2001). Proposed diagnostic criteria for neurocysticercosis. Neurology 57: 177–183
35. Revised diagnostic criteria of neurocysticercosis applicable to poor countries
• Garg RK. Diagnostic criteria for neurocysticercosis: some modifications are needed for Indian patients. Neurol. India 52(2), 171–177 (2004).
36. Diagnostic criteria for solitary cysticercus granuloma
• Rajshekhar V, Chandy MJ. Validation of diagnostic criteria for solitary cerebral cysticercus granuloma in patients
presenting with seizures. Acta Neurol. Scand. 96(2), 76–81 (1997).
37. Clinical and radiologic features consistent with a diagnosis of SCG
• A diagnostic and therapeutic scheme for a solitary cysticercus granuloma G. Singh, V. Rajshekhar,
J.M.K. Murthy, et al. Neurology 2010;75;2236
38. Clinical and radiologic features consistent with a diagnosis of SCG
• A diagnostic and therapeutic scheme for a solitary cysticercus granuloma G. Singh, V. Rajshekhar,
J.M.K. Murthy, et al. Neurology 2010;75;2236
39. TREATMENT
• Accurate characterization of disease - important for a rational therapy
• viability of cysts
• degree of the host’s immune response to the parasites
• location of the lesions
• Therapeutic approaches - include a combination of
• Symptomatic therapy
• Cysticidal drugs
• Surgical resection of lesions
• Placement of ventricular shunts
43. Parenchymal brain calcifications
• Represent sequelae of previous infections
• should not be treated with cysticidal drugs
• may be an incidental finding on neuroimaging – endemic areas
• prophylactic AED therapy - not justified
• AEDs - advised when associated with seizures
• Neuroimaging studies performed immediately after seizure relapse -
focal edema and abnormal contrast enhancement around previously
inert calcifications
44. Symptomatic therapy
• AEDs - adequate control of seizures - respond well to first-line AEDs
• Risk of seizure recurrence remains high as long as the granuloma is
visible on imaging as an enhancing lesion
• Outcome improves following resolution of SCG
• Seizure relapses are associated with the presence of residual
calcification
45. • Optimal length of antiepileptic drug therapy - has not been settled
• Should receive AED therapy for at least 2 years after the last seizure,
followed by gradual withdrawal
• Withdrawal is not recommended in patients with multicystic disease
– will end up with calcified lesions, and a substantial proportion will
have further seizure relapses
46. SCG - Recommendations
• Risk of seizure recurrence - related to the persistence of the
enhancement
• Currently used AEDs effectively prevent seizure recurrence
• Appropriate to continue AEDs until such time that the lesion is
actively degenerating - appears as an enhancing lesion on imaging
studies
• AED may be withdrawn once complete resolution of the granuloma is
demonstrated on follow-up imaging studies
47. • Risk of seizure recurrence - remains high if the granuloma resolves
leaving behind a calcific residue, longer duration of AED should be
considered
• Any AED may be used, newer non-enzyme-inducing AED might be
considered for the period of time that antihelminthic treatment is
administered - Both phenytoin and carbamazepine were shown to
increase metabolism of praziquantel and albendazole
A diagnostic and therapeutic scheme for a solitary cysticercus granuloma G.
Singh, V. Rajshekhar, J.M.K. Murthy, et al. Neurology 2010;75;2236
48. Cysticidal drugs - Albendazole
• Initially administered at doses of 15 mg/kg/day for 1 month
• Further studies - length of therapy could be shortened to 1 week
without lessening the efficacy of the drug
• usual dose 15 mg/kg per day for 2 weeks
• even to 3 days if the patient has SCG
• Albendazole destroys 70–80% of parenchymal brain cysts
• superior to praziquantel in trials comparing the efficacy
• Another advantage - also destroys subarachnoid and ventricular cysts
due to its different mechanism of action
49. Cysticidal drugs - Praziquantel
• destroys 60–70% of parenchymal brain cysticerci
• usual dose 50 mg/kg per day for 2 weeks
• single-day course – SCG - three individual doses of 25–30 mg/kg at 2
hour intervals
50. Vesicular cysts
• Reached a state of immune tolerance with the host
• may remain for years in the brain parenchyma
• only way to destroy these cysts is by the use of a cysticidal drug
• evidence favors the use of cysticidal drugs - provides clinical
improvement and resolution of lesions
• Single cyst: Albendazole 15 mg/kg/d for 3 days or praziquantel 30
mg/kg in three divided doses every 2 hours
51. Antihelminthics in SCG
• Two recent meta-analyses of randomized trials have evaluated the
effect of cysticidal drugs on neuroimaging and clinical outcomes of
patients with neurocysticercosis
• Better resolution of both colloidal and vesicular cysticerci
• Lower risk of seizure recurrence in patients with colloidal cysticerci,
and a reduction in the rate of generalized seizures in patients with
vesicular cysticerci
• Del Brutto OH, Roos KL, Coffey CS, Garcia HH. Metaanalysis: cysticidal drugs for
neurocysticercosis: albendazole and praziquantel. Ann Intern Med 2006
52. Seizure freedom with anthelminthic treatment
• Otte WM, Singla M, Sander JW, Singh G. Drug therapy for solitary cysticercus granuloma: a systematic review and meta-
analysis. Neurology. 2013 Jan 8;80(2):152-62
53. Granuloma resolution with anthelminthic treatment
• Otte WM, Singla M, Sander JW, Singh G. Drug therapy for solitary cysticercus granuloma: a systematic review and meta-
analysis. Neurology. 2013 Jan 8;80(2):152-62
54. Conclusion on Antihelminthics
• Conclusively established the benefit of anthelminthic treatment
• Significantly improved resolution rate of the granuloma
• Better seizure-freedom rates
• Anthelminthics might hasten the involution of the granuloma as well
as offer the clinical benefit of improved possibility of being seizure-
free
• No evidence, however, for either an increased or decreased risk of
residual calcification associated with anthelminthic treatment
55. Role of corticosteroids - SCG
• Administration of a short course of corticosteroids in conjunction
with anthelminthic treatment - to control edema and symptoms due
to the host inflammatory response - common practice
• Many variations of steroidal drugs, doses, and lengths of treatment
have been used
• most common regimen is 0·1 mg/kg per day of dexamethasone given
1 day before antiparasitic therapy commences and maintained for 1
or 2 weeks, followed by a slow taper
• Anecdotal observations of the benefits of corticosteroid treatment
regarding amelioration of certain manifestations (including seizures
and headache) - attributable to the inflammatory degeneration of
SCG
56. Seizure freedom with corticosteroid treatment
• Otte WM, Singla M, Sander JW, Singh G. Drug therapy for solitary cysticercus granuloma: a systematic review and meta-
analysis. Neurology. 2013 Jan 8;80(2):152-62
57. Granuloma resolution with corticosteroid treatment
• Otte WM, Singla M, Sander JW, Singh G. Drug therapy for solitary cysticercus granuloma: a systematic review and meta-
analysis. Neurology. 2013 Jan 8;80(2):152-62
58. Conclusion on corticosteriods
• No overall significant difference between the corticosteroid-treated
and control subjects -
• rates of seizure freedom
• granuloma resolution
• residual calcification
• Lack of benefit of corticosteroid treatment on various outcomes -
important finding in guiding treatment policies for SCG
59. • Corticosteroids are useful in the management of inflammatory
symptoms in multiple neurocysticercosis
60. Cysticercotic encephalitis
• Cysticidal drugs must not be used, may exacerbate the inflammatory
response within the brain parenchyma
• High doses of corticosteroids and osmotic diuretics are advised as the
first therapeutic measures - to reduce the severity of brain edema
• Should be prolonged for 2 to 3 weeks until the edema subsides.
• Refractory cases – decompressive craniotomies - to avoid the life-
threatening risk of intracranial hypertension
62. Subarachnoid cysts
• Medical treatment of small subarachnoid cysts localised to the
convexity of the cerebral hemispheres - similar parenchymal brain
cysts
• only difference - albendazole is the preferred drug because it
penetrates the subarachnoid space better and reaches higher
concentrations in the CSF
• Treatment of giant cysts in the Sylvian fissure is controversial - some
authors recommend surgical resection, others suggest medical
therapy with albendazole and corticosteroids might be an equally
effective but less aggressive approach
63. Hydrocephalus
• Intracranial hypertension – cysticercotic arachnoiditis, mass effect of
cysts located in basal subarachnoideal cisterns, or the obstruction of
CSF pathway by ventricular cysts.
• due to cysticercotic arachnoiditis - Immediate CSF drainage or shunt
placement
• high dose corticosteroids (dexamethasone, 16 mg/kg per day or
more) - frequently lead to temporary control of hydrocephalus
64. Ventricular cysts and ependymitis
• Could be treated by surgical resection or by antiparasitic treatment
• Consensus guidelines favour surgical
• Possible exception - small cysts located in lateral ventricle
• Favoured surgical approach –
• endoscopic removal of cysts in the lateral and third ventricles with a
flexible ventriculoscope
• Posterior approach for removal of fourth ventricular cysts
• Absence of ependymitis, permanent shunt placing is not necessary
• Shunt placement should follow or even precede the excision of
ventricular cysts associated with ependymitis
65. References
• Garcia HH, Nash TE, Del Brutto OH. Clinical symptoms, diagnosis, and
treatment of neurocysticercosis. Lancet Neurol. 2014 Dec
• Del Brutto OH. Neurocysticercosis. Handb Clin Neurol. 2014
• Singh G, Rajshekhar V, Murthy JM, Prabhakar S, Modi M, Khandelwal
N, Garcia HH. A diagnostic and therapeutic scheme for a solitary
cysticercus granuloma. Neurology. 2010 Dec 14
• Otte WM, Singla M, Sander JW, Singh G. Drug therapy for solitary
cysticercus granuloma: a systematic review and meta-analysis.
Neurology. 2013 Jan
• Del Brutto OH, Roos KL, Coffey CS, García HH. Meta-analysis:
Cysticidal drugs for neurocysticercosis: albendazole and praziquantel.