Glutamic acid-coated Fe3O4 nanoparticles for tumor-targeted imaging and therapeutics

We have developed surface functionalised Fe₃O₄ magnetic nanoparticles (MNPs) based system that can be used for tumor-targeted multimodal therapies and MR imaging. Biocompatible, non-essential amino acid (glutamic acid) was introduced onto the surface of Fe₃O₄ MNPs to provide functional sites for binding of chemotherapeutic drugs. These glutamic acid-coated Fe₃O₄ MNPs (GAMNPs) exhibit good water-dispersibility, magnetic responsivity and pH dependent charge conversal feature. The magnetic core as well as organic shell of GAMNPs was characterized by XRD, TEM, DLS, FTIR, PPMS and UV-visible spectroscopy and zeta-potential analyzer etc. The broad spectrum anticancer drugs, doxorubicin hydrochloride (DOX) and methotrexate (MTX) were electrostatically and covalently conjugated to the surface of GAMNPs, respectively for combination chemotherapy. These dual drugs loaded system (DOX-MTX-GAMNPs) shows pH dependent release behaviour of both the drugs and enhanced toxicity towards breast cancer cell line (MCF-7) as compared to their individual treatment. Fluorescence microscopy and flow cytometric analyses confirmed the successful uptake of drug loaded system into MCF-7 cell lines. Further MTX being analogue of folic acid, its co-delivery with DOX would help in internalization of both the drugs into MCF-7 cells. These GAMNPs also show good heating efficiency under AC magnetic field (Intrinsic loss power, ILP = 0.95 and 0.73 and 0.48 nHm²/Kg at Fe concentration of 0.5, 1 and 2 mg/ml, respectively) and transverse relaxivity (r₂ = 152 mM^-1 s^-1) indicating their potential capability for hyperthermia therapy and MRI tracking. Furthermore, it has been observed that the combination of chemotherapeutic drugs and hyperthermia leads to an enhancement of cytotoxicity in MCF-7 cells.

Acute encephalopathy with biphasic seizures and late reduced diffusion

Acute encephalopathy with biphasic seizures and reduced diffusion (AESD) is a syndrome of encephalopathy characterized by biphasic seizures and altered consciousness in the acute stage followed in the subacute stage by restricted diffusion in the subcortical white matter on magnetic resonance imaging. The etiology of AESD has been attributed to viral infection like influenza A and human herpes virus 6. The exact pathogenesis of AESD is uncertain. Here we report a case of AESD, diagnosed based on clinicoradiological correlation.

Antenatal diagnosis of iniencephaly: sonographic and MR correlation: a case report

Iniencephaly is an uncommon and fatal neural tube defect involving the occiput and inion, this occurs together with rachischisis of the cervical and thoracic spine, and retroflexion of the head. We report the ultrasound (US) and magnetic resonance (MR) imaging findings of a case of iniencephaly with clubfeet and arthrogryposis. The diagnosis of iniencephaly is easy to make on ultrasound due to the typical star-gazing fetus. However, the details of the fetal brain and spinal cord may not be adequately delineated on US. We found MR imaging to be superior for depicting central nervous system abnormalities. MR imaging has evolved as an imaging modality and it is complementary to fetal US, yet US remains the screening modality of choice.

Adductor insertion avulsion syndrome with stress fracture of femoral shaft: MRI findings

Chronic vague hip pain may be caused by stress-related injury in the proximal or mid-femoral diaphysis. This has been described as an entity called adductor insertion avulsion syndrome, or thigh splints. In the appropriate clinical setting, the radiologist interpreting the magnetic resonance imaging must be aware of this condition as its imaging findings are subtle. The diagnosis will help the clinician plan the appropriate management. Magnetic resonance imaging can also depict the complications such as stress fracture.

MRI diagnosis of hypertrophic osteoarthropathy from a remote childhood malignancy

Hypertrophic osteoarthropathy (HOA) is a clinico-radiological syndrome characterized by digital clubbing, periosteal proliferation, bone pain, synovitis and arthralgia, all of these being commonly symmetrical. It is occasionally associated with nasopharyngeal lymphoepitheliomas and may develop before or after development of lung metastases in these patients. We report a case of a healthy 22-year-old female who presented to our institution with pain and swelling in the thighs and legs. She had a history of childhood nasopharyngeal lymphoepithelioma. Radiographs of the knees were negative. Magnetic resonance imaging (MRI) showed features suggestive of bilateral periostitis. Because of the propensity of the rare childhood nasopharyngeal lymphoepithelioma to present with HOA, this entity was included in the differential diagnosis. A subsequent chest radiograph and CT demonstrated a lung and mediastinal mass that were histologically confirmed to be metastatic. To the best of our knowledge, HOA and metastases from nasopharyngeal lymphoepithelioma occurring after such a long time interval have not been previously reported. Early demonstration and consideration of HOA on the basis of MRI, lead to expeditious and appropriate subsequent investigation.

Pre- and post-therapy MR imaging in fibrodysplasia ossificans progressiva

Fibrodysplasia ossificans progressiva, also known as myositis ossificans progressiva, is characterized by congenital skeletal malformations and progressive ectopic bone formation in connective tissues. The disorder presents as rapidly growing masses usually in the neck or paraspinal region with stiffness in the adjoining joints. The preosseous lesions involve the fascia, ligaments, tendons, and skeletal muscle. These lesions occasionally resolve but more often progress to form ectopic ossification. We present a boy who had a characteristic clinical presentation. Magnetic resonance (MR) imaging conducted in the preosseous stage of the lesion revealed the pathology, resulting in early therapy and resolution of the preosseous lesion without progression to ossification. To the best of our knowledge, post-therapy follow-up MR imaging in such a case has not been reported.

Spontaneous intracranial hypotension: A study of six cases with MR findings and literature review

Spontaneous intracranial hypotension is clinically characterized by orthostatic headache and other symptoms caused by low cerebrospinal fluid pressure due to leakage of cerebrospinal fluid from dural punctures or other medical causes. The other symptoms are mainly due to traction of the cranial and spinal nerves owing to descent of the brain caused by low cerebrospinal fluid pressure. Magnetic resonance imaging is very useful in the diagnosis because of its characteristic findings. We describe the MRI findings in six cases that had variable clinical presentation.

MR spectroscopy-aided differentiation: "giant" extra-axial tuberculoma masquerading as meningioma

Tuberculosis is common in the developing world and in developed nations secondary to increasing immunocompromise in the population. It commonly causes meningitis and parenchymal tuberculomas. We present a case of an unusual masslike "giant" extra-axial tuberculoma during pregnancy. Unusual morphology and size at imaging made meningioma a close differential. MR spectroscopy served to complement MR imaging, providing diagnostic confirmation and depicted findings characteristic of a tuberculoma.

Bilateral optic pathway glioma with intracranial calcification: Magnetic resonance imaging and magnetic resonance spectroscopy findings

Optic nerve glioma is the most common primary neoplasm of the optic nerve in childhood. It can extend intracranially along the optic pathway (optic pathway glioma). The lesion tends to present with decreased visual acuity in the affected eye, but can cause additional symptoms when it is large. Local involvement within the orbit can be characterized using CT, but MRI is superior in showing the intracranial extent of the lesion. Intracranial calcification in optic pathway glioma is rare. We present a rare case of optic pathway glioma with calcification in the intracranial component. Also, we describe MR spectroscopy (MRS) findings in this case.

Multiple hemangiomas involving the vertebral column

Hemangiomas are benign, slow-growing skeletal and soft tissue tumors that commonly involve the bony spine. When found in the spine, they are usually asymptomatic, but can sometimes be associated with local pain and/or neurological deficits. We report the case of a middle-aged Indian male with multiple hemangiomas involving almost all the vertebrae contiguously from C2 to S1 vertebral levels. These were discovered incidentally when a magnetic resonance scan was performed for backache. To the best of our knowledge, such extensive involvement of the spine has not been reported previously.

Tuberculous mastoiditis

A 14 month old child with intractable painless otorrhoea resistant to conventional treatment with sadden onset facial palsy was referred to us for HRCT of temporal bone. A rare diagnosis of tuberculous mastoiditis was made which was confirmed by histopathological reports. In this case the use of a Multislice CT scanner (Siemens Volume Zoom) in demonstrating the intricate involvement of the middle and inner ear structures by the disease is accentuated.