Cushing's disease: Does low-dose pasireotide offer a comparable efficacy and safety to high-dose?

SUMMARY: Whilst literature is expanding on pasireotide use in the management of Cushing's disease (CD), there is still currently much unknown about long-term and low-dose pasireotide use in CD. We present a 60-year-old female with residual CD after transphenoidal surgery (TSS), being successfully managed with S.C. pasireotide for over 10 years. For 6 years, her S.C. pasireotide was inadvertently administered at 360 µg twice daily (BID), almost half the recommended dose of 600 µg BID. Despite the low-dose, her urinary free cortisol (UFC) normalised within 6 months and Cushingoid features resolved. She remained in biochemical and clinical remission on the same low-dose for 6 years, before a medication audit discovered her mistaken dose and directed her to take 600 µg BID. With the higher dose 600 µg BID for the next 5 years, her glycaemia worsened without any changes in her UFC and residual tumour volume. Our case showed the continuing effectiveness and safety of treatment with S.C. pasireotide for more than 10 years, and that a low-dose regimen may be considered an option for responders by its safety profile. LEARNING POINTS: A lower dose of pasireotide may be effective in the initial treatment of CD than the recommended 600 µg BID dosage, though more studies are required to explore this. Low-dose pasireotide use has the benefit of minimising adverse effects. In the long-term, pasireotide has a sustained clinical and biochemical effect and is well tolerated.

Serial magnetic resonance imaging findings of intracerebral spread of listeria utilising subcortical U-fibres and the extreme capsule.

We present a case of Listeria monocytogenes cerebral abscess with axonal spread via the subcortical U-fibres and extreme capsule on magnetic resonance imaging, with follow-up studies demonstrating serial reduction in oedema and enhancement pattern of the white-matter fibre tracts following antimicrobial treatment. We discuss the microbiological mechanism of bacterial mobility to account for these unique imaging features. Recognition of this distinct pattern of spread of L. monocytogenes cerebral abscess may aid in diagnosis and enable early microbiological culture and treatment.

Neuromelioidosis: Craniospinal MRI Findings in Burkholderia pseudomallei Infection.

PURPOSE: To investigate magnetic resonance imaging (MRI) findings of central nervous system (CNS) infection with Burkholderia pseudomallei. METHODS: Retrospective analysis of 10 patients (5 male and 5 female, age range from 13 to 69 years) with CNS melioidosis confirmed on culture of blood, sputum, cerebrospinal fluid, brain biopsy, and postmortem brain tissue. Clinical data were collected and MRI brain and/or spine were independently reviewed. RESULTS: Seven patients with brain parenchymal or intramedullary spinal cord lesions demonstrated rim-enhancing microabscesses with propensity for white matter tracts including the corticospinal tracts, corpus callosum, and cerebellar peduncles. Three of these 7 patients also showed thickening and enhancement of the trigeminal nerves with contiguous spread to brain stem trigeminal nuclei. Three patients had isolated extraaxial disease with findings including meningeal enhancement, extradural abscess, skull osteomyelitis, and scalp abscess. CONCLUSION: Spread of microabscesses along white matter tracts and frequent trigeminal nerve involvement are unique imaging characteristics of CNS melioidosis. These findings may provide insight into potential mechanisms for B. pseuodomallei entry into the CNS through direct axonal transport in cranial nerves bypassing the blood brain barrier. Prompt recognition of the neuroimaging features of this potentially fatal infection may allow for early microbiological culture and treatment.

Pontine Tegmental Cap Dysplasia: MR Evaluation of Vestibulocochlear Neuropathy.

Pontine tegmental cap dysplasia (PTCD) is recently recognized as a rare congenital brain stem malformation with typical neuroimaging hallmarks of ventral pontine hypoplasia and vaulted pontine tegmentum projecting into the fourth ventricle. PTCD patients also demonstrate variable cranial neuropathy with predilection for involvement of the vestibulocochlear and facial nerves. We present a case of PTCD diagnosed on MRI in the neonatal period. During early infancy, the patient displayed features of multiple cranial neuropathies and bilateral hearing loss. At the age of 2, the patient underwent further MRI assessment with dedicated high resolution T2 SPACE sequence to delineate the cranial nerve deficiencies.

Lack of security of networked medical equipment in radiology.

OBJECTIVE. There are few articles in the literature describing the security and safety aspects of networked medical equipment in radiology departments. Most radiologists are unaware of the security issues. We review the security of the networked medical equipment of a typical radiology department. MATERIALS AND METHODS. All networked medical equipment in a radiology department was scanned for vulnerabilities with a port scanner and a network vulnerability scanner, and the vulnerabilities were classified using the Common Vulnerability Scoring System. A network sniffer was used to capture and analyze traffic on the radiology network for exposure of confidential patient data. We reviewed the use of antivirus software and firewalls on the networked medical equipment. USB ports and CD and DVD drives in the networked medical equipment were tested to see whether they allowed unauthorized access. Implementation of the virtual private network (VPN) that vendors use to access the radiology network was reviewed. RESULTS. Most of the networked medical equipment in our radiology department used vulnerable software with open ports and services. Of the 144 items scanned, 64 (44%) had at least one critical vulnerability, and 119 (83%) had at least one high-risk vulnerability. Most equipment did not encrypt traffic and allowed capture of confidential patient data. Of the 144 items scanned, two (1%) used antivirus software and three (2%) had a firewall enabled. The USB ports were not secure on 49 of the 58 (84%) items with USB ports, and the CD or DVD drive was not secure on 17 of the 31 (55%) items with a CD or DVD drive. One of three vendors had an insecure implementation of VPN access. CONCLUSION. Radiologists and the medical industry need to urgently review and rectify the security issues in existing networked medical equipment. We hope that the results of our study and this article also raise awareness among radiologists about the security issues of networked medical equipment.

Ultrasound Doppler evaluation of the pattern of involvement of varicose veins in Indian patients.

Doppler evaluation of lower limb veins was performed to evaluate the pattern of involvement of various sites of incompetence in Indian patients with varicose veins. A prospective Doppler study of 100 consecutive limbs in patients who presented with varicose veins to the vascular surgery department of a tertiary care hospital in India. The Clinico-Etiological Anatomical and Pathological (CEAP) classification was applied for assessment. Doppler evaluation of both superficial and deep venous system of the lower limbs was performed. The data of various sites of reflux was analysed to find the patterns of venous involvement in the affected patients. Superficial venous reflux was seen in all the patients. Deep venous reflux was seen in 50% of the lower limbs examined. Doppler is a simple non-invasive test, and is well tolerated by the patients. Deep venous reflux is common in Indian population, though it rarely occurs in isolation, and is usually associated with superficial reflux.

Evaluation of radiation risk and work practices during cerebral interventions.

This study was intended to evaluate radiation risk to patients during cerebral interventions and the contribution to this risk from work practices. Thirty nine patients undergoing cerebral interventions in a digital subtraction angiography suite were included in this study. Patients who underwent cerebral interventions were categorised into two groups according to the number of cerebral interventions performed on them, and their effective doses were calculated. The effective dose for patients undergoing a single cerebral intervention (group A) varied from 1.55 to 15.9 mSv and for multiple cerebral interventions (group B) varied from 16.52 to 43.52 mSv. Two patients who underwent multiple cerebral interventions (group B) had alopecia of the irradiated scalp.

MR ventriculography for the study of CSF flow.

BACKGROUND AND PURPOSE: Various MR techniques have been used to assess CSF flow and to image the subarachnoid spaces and ventricles. Anecdotal reports describe the use of intrathecal and intraventricular gadolinium-based contrast agents in humans and animals. We sought to determine the clinical usefulness of gadolinium-enhanced MR ventriculography for assessing CSF flow in patients with various neurologic conditions. METHODS: Five patients (three female and two male patients aged 6 months to 65 years) were included in the study. After performing sagittal, coronal, and axial T1-weighted MR imaging of the brain, 0.02-0.04 mmol of gadodiamide was injected into the lateral ventricle. Sagittal, coronal, and axial T1-weighted imaging was repeated soon after the injection. We were specifically looking for the site of obstruction to CSF flow in those patients with hydrocephalus, communication between cysts and ventricles, elucidation of suspicious intraventricular lesions, and patency of third ventriculostomies. RESULTS: MR ventriculography showed good delineation of the ventricular system in all patients. In one patient with carcinomatosis and hydrocephalus, a block to contrast material flow was detected at the right foramen of Luschka. In another patient with hydrocephalus, partial block to the flow of contrast material was demonstrated at the right foramen of Monro. In a patient with hydrocephalus and a posterior fossa cyst, flow of contrast material was blocked between the third ventricle and the cyst, with a thin streak of contrast material in the aqueduct. As an assessment of the patency of a third ventriculostomy, MR ventriculography showed flow of contrast material into the suprasellar cisterns from the third ventricle in one patient and absence of flow in another. CONCLUSION: MR ventriculography is a safe technique for assessing CSF flow, with application in determining the site of obstruction in hydrocephalus, in assessing communication between cysts and the ventricle, and in determining the functioning status of endoscopic third ventriculostomies.

Solitary hemispheric demyelination in acute disseminated encephalomyelitis: clinicoradiological correlation.

We retrospectively studied 13 patients with solitary hemispheric demyelination in acute disseminated encephalo--myelitis (solitary-ADEM) to look for specific MRI features. Thirteen patients were subjected to routine MRI with varying initial clinical diagnosis, including demyelination, neoplasm, encephalitis and infarct. The provisional MRI diagnosis was based on lesion morphology, size, location, mass effect, effect on adjacent sulci, cisterns and gyral shape. On long repetition time (TR)/long echo time (TE) spin echo sequences, the lesions were heterogeneously hyperintense, and on short TR/short TE spin echo sequences, heterogeneously hypointense. Later, the provisional MRI diagnosis was corroborated with clinical parameters such as multimode-evoked potentials, electro--physiological studies and analysis of cerebrospinal fluid (CSF) in order to establish a definitive diagnosis. The diagnosis was established in all except one patient with tumour-like clinical and MRI features. The combination of MRI features and clinical parameters can establish a definitive diagnosis in the majority of cases, and this avoids a biopsy.