Brainstem ischemic lesions on MRI in children with tuberculous meningitis: with diffusion weighted confirmation

Introduction  The Western Cape in South Africa has one of the highest incidences of tuberculous meningitis (TBM) in the world. Despite therapy, the outcome in children with advanced TBM remains dismal. Magnetic resonance imaging (MRI) has been shown to be superior to computed tomography (CT) in demonstrating ischemia in TBM, especially of the brainstem. The objective of this study was to characterize brainstem lesions and association with clinical findings in children with TBM by using MRI. Materials and methods  CT and multiplanar MRI scans were performed in 30 children with proven TBM. From this group, a subgroup with radiological ischemic changes of the brainstem were identified. Radiological findings in these patients were then correlated with severity of disease, motor deficit, and outcome after 6 months. Results  Radiological brainstem abnormalities were identified in 14 out of 30 children. Thirty-eight brainstem lesions were confirmed to be ischemic. The severity of disease at presentation, degree of motor deficit, and developmental outcome after 6 months of the children with ischemic brainstem lesions was poorer compared to those children without brainstem involvement. However, both sensitivity and specificity of the MRI brainstem lesion detection for clinical outcome proved low. Conclusion  A significant percentage of children with TBM have ischemic brainstem lesions. These are poorly visualized on conventional CT. MRI scanning is more sensitive in detecting these lesions and localizing them. There appears to be some association between MRI-detected brainstem lesions and clinical outcome. The exact meaning of these lesions and their implication for the patient's management require further clarification.     

Case of Gerstmann-Str?ussler-Scheinker syndrome (GSS-P102L) mimicking variant Creurtzfeldt-Jakob disease in clinical manifestation and MRI findings]

We reported a 51-year-old woman with Gerstmann-Str?ussler-Scheinker syndrome (GSS P102L) manifesting characteristic MRI findings. At the age of 45, She developed gait disturbance with muscle atrophy in the lower limbs and positive plantar flexor sign. Subsequently, sensory disturbance such as refractory pain in the lower limbs and ataxic gait were developed at the age of 49. Following these clinical symptoms, she finally demonstrated rapid progressive cognitive dysfunction. Just after presenting cognitive dysfunction, cranial MRI was performed. Cranial MRI with diffusion-weighted imaging and FLAIR imaging demonstrated abnormal high intensity lesions in the bilateral pulvinar, caudate nuclei and cerebral cortex. The degree of high signal at the pulvinar was less than those of the cortex and caudate nuclei. A proline-for-leucine substitution at codon 102 of the prion protein gene was demonstrated. These results allowed the diagnosis of GSS (P102L). This is a rare case of GSS (P102L) presenting with high intensity lesions in the bilateral pulvinar on MRI.     

A case of progressive multifocal leukoencephalopathy presenting white matter MRI lesions extending over the cerebral cortex and a marked decrease in cerebral blood flow on SPECT, and associated with HTLV-I infection]

We report a 47-year-old woman with progressive multifocal leukoencephalopathy (PML). She was a carrier of HTLV-I virus, and developed subacute right hemiparesis and marked motor aphasia. She had a malignant lymphoma in the left neck and basal cell carcinoma in the right inguinal region. Three months after the onset, she became unable to walk because of the right leg weakness or to speak because of motor aphasia. Magnetic resonance imaging (MRI) revealed multifocal T2-high lesions in the white matter of the left frontal lobe, and a brain biopsy revealed demyelinating pathology. A biopsy of the left parotid gland revealed a diffuse pleomorphic type large B cell lymphoma. Although anti-HTLV-I antibody was positive in the serum and cerebrospinal fluid (CSF), no adult T-cell leukemia (ATL) cells were found in the blood or CSF. The patient was then admitted to our hospital. Neurological examinations revealed severe motor aphasia, mild sensory aphasia/cognitive impairment, right hemiplegia, mild right hemihypesthesia, limb-kinetic apraxia in the left hand, idiomotor apraxia, agraphia, perseveration, marked spasticity and brisk tendon reflex in four extremities, and positive bilateral pathological reflexes. MRI showed multifocal T2-high lesions mainly in the cerebral white matter, predominantly in the left hemisphere, and partly in the cerebral cortex. No gadolinium enhancement was found. In addition, 99mTcECD-SPECT showed a broad decrease in cerebral blood flow (CBF) in the cortex. Anti-HTLV-I antibody was positive but anti-HIV antibody was negative in serum. ATL cells were found in 1-3% of the peripheral white blood cells after admission. CSF examination revealed that the cell count (1/microl), protein level (24 mg/dl), and IgG index (0.4) were all normal. However, the myelin basic protein level (321 pg/ml; normal < 102) was increased, JC virus DNA was detected by PCR, and anti-HTLV-I antibody (x 8) was detected in CSF. The regulatory region of the JC virus DNA in the CSF was partly deleted; immunostaining with anti-JC virus protein antibodies revealed the existence of JC virus in biopsied brain specimens, and these findings were consistent with PML. Her symptoms such as motor aphasia, cognitive dysfunction and left hemiparesis were subacutely progressive, and she developed akinetic mutism two weeks after admission. Since the efficacy of cytosine arabinoside for PML has been reported, she was administered 80 mg/day of the drug for five days. After treatment, her communication function was mildly improved but the efficacy was transient. Since it has been reported that HTLV-I, as well as HIV, activates the JC virus promoter and its proliferation, the latent infection of HTLV-I in the central nervous system (CNS) in this case might have stimulated the JC virus proliferation, promoting lesion extension over the cerebral cortex. There have been only a few reports of broad decreases in CBF by SPECT in PML patients. Further MRI and SPECT studies on PML patients are therefore necessary to evaluate the significance of HTLV-I in promoting the JC virus infiltration into the CNS.     

A case of Japanese encephalitis presenting with unilateral lesions in diffusion-weighted MRI]

We report the findings of diffusion-weighted MRI (DWI) taken serially in a patient with Japanese encephalitis (JE). The patient was a 43-year-old woman presenting with headache, high fever and consciousness disturbance. The diagnosis of JE was made based on more than fourfold elevation of serum complement fixation antibody titer for JE virus in the convalescent phase of illness. The DWI on the second day of illness (Day-2) disclosed high-signal intensity lesions in the left thalamus, substantia nigra and frontal lobe cortex. The signal intensity of these lesions on the DWI increased on Day-3 but gradually decreased thereafter and normalized on Day-28. The improvement of the DWI findings was paralleled with that of the consciousness level and the cell number and neuron specific enolase concentration in the CSF, suggesting that DWI is useful for evaluation of the disease activity in JE. The lesions in the brain suffering from Japanese encephalitis are usually bilateral and diffuse. To our knowledge, this is the first report of JE presenting with unilateral lesions on MRI, of which phathomechanism remains to be elucidated.     

A patient with neuroborreliosis presenting gadolinium-enhanced MRI lesions in bilateral facial nerves]

We report a 33-year-old man with bilateral facial paralysis due to neuroborreliosis. About three weeks after rhinorrhea and fever lasting four days, he noticed fatigue in the legs and paresthesia in all four extremities. Another week later, he developed paresthesia in his tongue and bilateral facial muscle weakness, and was admitted to our hospital. On admission, neurological examination revealed moderate bilateral facial muscle weakness, mild paresthesia in the tongue and four extremities, and decreased Achilles tendon reflex bilaterally. Mild pleocytosis and increased protein were found in the cerebrospinal fluid (CSF). IgM antibodies that reacted with the antigens of Borrelia garinii and Borrelia afzelii were found in his serum. Clinically and serologically, he was thus diagnosed as having neuroborreliosis. Brain MRI revealed gadolinium-enhanced lesions of the bilateral facial nerves in the facial nerve canal portion. After three weeks of treatment with 100 mg/day doxycycline and 2 g/day ceftriaxone sodium, his symptoms and CSF abnormalities were rapidly improved. Although facial nerve paralysis is a major symptom of neuroborreliosis, the present report is the first to detect the inflammatory lesions of the facial nerves in the facial nerve canal portion by MRI.     

A case of cerebral venous thrombosis with reversible brain parenchymal lesions: usefulness of diffusion weighted imaging and measurement of apparent diffusion coefficient]

A 47-year-old man with a history of thrombophlebitis of his left leg for several years presented with a mild left hemiparesis and ipsilateral hypesthesia. Magnetic resonance imaging showed subacute thrombosis of the superior sagittal sinus and a cortical vein of the right cerebral hemisphere. A linear hyperintense area was found in the white matter of the right postcentral gyrus on T 2- and diffusion weighted axial imagings on the 7 days after the onset. The patient was treated conservatively, and his clinical course was uneventful. His neurological dysfunctions recovered within approximately three weeks after the onset. The white matter lesion in the right postcentral gyrus also disappeared one month later. The apparent diffusion coefficients (ADCs) in the white matter of the pre- and postcentral gyrus were measured bilaterally on the ADC mapping imaging. In the subacute stage, the ADC values in the white matter of the right pre- and postcentral gyrus were 0.50 x 10(-3) mm2/sec and 0.91 x 10(-3) mm2/sec, respectively. The %ADC indicating the ratio of ADC value of the lesion to that of the contralateral brain tissue was calculated. The %ADCs in the white matter of the pre- and postcentral gyrus were 64.9% and 124.5% respectively. In the chronic stage, the ADC values in the white matter of the right pre- and postcentral gyrus were 0.96 x 10(-3) mm2/sec and 0.99 x 10(-3) mm2/sec, and the %ADCs improved to 106.7% and 106.5% respectively. The lesions in the white matter of the right pre- and postcentral gyrus were reversible. The former was thought to be mainly ascribed to cellular edema and the latter was vasogenic edema. The present case showed when %ADC of the ischemic lesion in cerebral venous thrombosis was higher than 60%-70%, conservative therapy alone is sufficient effective for the improvement of neurological deficits.     

A case of non-herpetic acute encephalitis presenting high intensity lesion at unilateral temparal cortex on MR FLAIR image]

We reported a case of non-herpetic acute encephalitis with unilateral temporal cortex lesion revealed by MR imaging and SPECT study. The patient was an eighteen years old woman who developed tonic-clonic seizure after common cold symptom. She was healthy before this episode. Neurological abnormality was only a single convulsion at onset and there was no other abnormal physical and neurological signs except for low grade fever. Electroencephalogram showed spike and slow wave complex of 2 Hz focused on a right posteriotemporal point (T 6) and an MR FLAIR (fluid-attenuated inversion recovery) image revealed a high signal intensity area at right temporal cortex. There was a decrease of cerebral blood flow in the same portion on SPECT study. This lesion was obscure on T1 and T2 MR images. Cerebrospinal fluid showed pleocytosis with normal glucose level and protein concentration. Bacterial and fungal cultures of CSF were negative and a detection of tubercule bacillus by PCR hybridization method was also negative. Although CSF findings suggested viral infection of CNS, virological study could not demonstrate infections of herpes simplex virus type 1, type 2, varicella-zoster virus, cytomegalovirus, measles virus, mumps virus, Japanese encephalitis virus, and influenza virus type A and B. After infusion of acyclovir and antibiotics, the patient was discharged from our hospital without sequelae of encephalitis. EEG was normal at this point and a high intensity area of MR FLAIR image disappeared two months later. SPECT findings were normalized six months later. The encephalitis presenting unilateral temporal cortex lesion without the infection of herpes simplex virus is thought to be very rare. Our case was distinguished from non-herpetic acute limbic encephalitis by an extent of the lesion and clinical manifestations. MR FLAIR image was useful for the detection of the lesion in this case.     

Herpes simplex encephalitis with expanded cerebral cortex lesions on T1-weighted MRI after clinical improvement: a case report]

We described a 58-year-old woman with herpes simplex encephalitis (HSE), who initially had fever and developed impaired consciousness. Cerebrospinal fluid (CSF) examination showed mononuclear pleocytosis and the existence of herpes simplex virus (HSV) DNA. The first T1-weighted MR image showed symmetrical swelling and low signal intensity lesions in the medial temporal lobes and hippocampus. T2-weighted MR image showed high signal intensity lesions in the medial temporal lobes, the amygdala, the hippocampus, the insula and the cingulate gyri bilaterally. After the treatment with intravenous acyclovir and betamethasone, impaired consciousness and recent memory disturbance gradually improved. On the second T1-weighted MR image examination, eighteen days after the onset, high signal intensity lesions were demonstrated in the right medial temporal lobe, the right hippocampus, the left insula and the bilateral cingulate gyri. Although the clinical symptoms had improved significantly over three months, the high signal intense lesions on T1-weighted MR images were also detected in the left medial temporal lobe, the right insula, and the straight gyrus. Brain CT did not demonstrate any abnormalities. The repeated CSF examinations showed negative HSV DNA and a decreased number of WBC. However, oligoclonal IgG bands were continuously positive. Myelin basic protein level and IgG index increased in parallel with the expansion of the cerebral lesions on T1-weighted MR images. In the present case, the abnormality of T1-weighted MRI was thought to indicate hemorrhagic inflammatory lesions that could not be detected by CT. The increased level of myelin basic protein, the elevated IgG index and the continuous positive oligoclonal IgG indicated continuous immunologic response against HSV in these lesions.     

A case of portal-systemic shunt encephalopathy due to congenital portal vein hypoplasia presenting with abnormal cerebral white matter lesions on the MRI]

A 49-year-old woman, without any past history of liver diseases and blood transfusion, was admitted to our service because of somnolence, and flapping tremor. Neurologically, she was drowsy and disoriented. She had bilateral pyramidal tract signs and flapping tremor. Although the laboratory examination showed marked hyperammonemia (217 micrograms/dl), neither abdominal CT nor liver biopsy showed any evidence of liver cirrhosis. An abdominal angiography showed portal vein hypoplasia associated with the portal-systemic shunt. A T2-weighted MRI showed the high intensity areas in the bilateral deep cerebral white matter, and the posterior limbs of the bilateral internal capsules. This is a rare case of portal-systemic shunt encephalopathy due to congenital portal vein hypoplasia presenting with abnormal cerebral white matter lesions on the MRI.     

Two case mimicking cerebral tuberculoma in MRI diffusion weighted-images with difficult preoperative diagnosis]

Two cases with a high signal intensity core with laminar structure based on diffusion weighed-images (DWI) mimicking intracerebral tuberculoma were herein reported. Both patients were suspected to have pulmonary tuberculosis in their past history and/or based on chest X-ray findings. DWI demonstrated a high signal intensity core with laminar structure, thus suggesting the presence of an intracerebral tuberculoma. As initial therapy, both patients received anti-tuberculous drugs, however, their symptoms did not improve, and the lesions were observed to have increased in MRI. As a result, a biopsy was carried out to clarify the nature of the disease. A pathological examination showed the former to be a brain abscess while the latter was metastatic carcinoma. In such cases mimicking intracerbral tuberculoma based on DWI, anti-tuberculous drugs are first treatment of choice, however, a biopsy should be performed as early as possible if the medication dose not show a significant response.     

A case of Kearns-Sayre-Shy syndrome with abnormal signal intensity on MRI in cerebral white matter and brainstem

A 42-year-old woman was admitted for complaining of gait disturbance lasting for 2 years. She had a past history of hearing loss and bilateral ocular ptosis since her age of 21 years. Neurological examinations revealed severe external ophthalmoplegia, ptosis and muscular weakness of neck and extremities, but no dementia. Laboratory examinations showed high level of serum CK and slight elevations of CSF protein, lactate and pyruvate. The QT interval on ECG was prolonged. The EEG finding was slightly abnormal. The neurogenic pattern on EMG was noted. Muscle biopsy was performed at the quadriceps muscle. Its specimens demonstrated mixed changes of muscular atrophy and ragged red fibers. From these findings, Kearns-Sayre-Shy syndrome was diagnosed. It was noted in this case that brain MRI (T2-weighted image) revealed bilateral diffuse high signal intensity areas on cerebral white matter and brainstem. It seems that the lesions of central nervous system may progress subclinically for many years in cases of KSS, as our case shows.     

Case of X-linked lymphoproliferative syndrome (XLP) with multiple nodular lesions in the brain]

We reported a case of X-linked lymphoproliferative syndrome (XLP) with multiple nodular lesions in the brain and lungs. A 21-year-old man was admitted because of one month history of low grade fever, headache, nausea, and amnesia. He developed agammaglobulinemia following Epstein-Barr virus infection at 3-year-old, and thereafter was administered 7.5g of immunoglobulin every 3 weeks with a diagnosis of XLP. Physical examination was unremarkable on admission. Neurological examination revealed disorientation of time, and bilateral gaze-evoked nystagmus. Neuropsychological tests demonstrated impairment of recent memory and calculation. Pleocytosis (83/microl) and increase of protein (1269 mg/dl) and IgG (141 mg/dl) in the CSF were observed. Brain MRI showed multiple nodular lesions with high intense signal on T2-weighted images and Gd-DTPA enhancement on T1-weighted images. Chest CT showed multiple nodular lesions in the bilateral lungs. The needle lung biopsy was performed, which showed infiltration of lymphocytes around the vessels. An immunohistochemical study showed that the infiltrating cells were mainly CD8 positive T lymphocytes. B lymphocyte and plasma cells were not seen. The histological findings excluded intravascular malignant lymphoma and lymphomatoid granulomatosis. Therefore we diagnosed lymphoid vasculitis. The patient developed pancytopenia caused by hemophagocytic syndrome 48 days after admission and was treated with 1 g of methylprednisolone per day for 3 days and a tapered dose of steroid (500 mg to 125 mg of methylprednisolone and 60 mg to 10mg of predonisolone) for 21 days, which resulted in the improvement of clinical features (hemophagocytic syndrome and central nervous system symptoms) and the abnormal CSF findings. The multple nodular lesions in the brain and the lungs shrank 1 month after treatment and disappeared 11 months later. There are few reports concerning lymphoid vasculitis with XLP, and no effective treatment has been described. Our case suggests that steroid therapy may be useful for the treatment of lymphoid vasculitis in XLP.