-
[show abstract]
[hide abstract]
ABSTRACT: We present a method of quantifying cerebral blood volume using dynamic susceptibility contrast. Our approach combines T(2)-weighted echo planar imaging (EPI) pulse sequences and reference scans that determine the parenchymal T(1) changes resulting from an injection of a gadolinium chelate. This combined T(2)- and T(1)-weighted approach (the "bookend" technique) has been shown to be effective in the quantification of gradient-echo (GRE) (T(2)*-weighted) perfusion images but has not been applied to spin-echo EPI (SE-EPI) (T(2)-weighted) images. The physics related to blood volume measurement based on T(2)- and T(2)*-weighted EPI sequences is known to be different, and there is a question as to whether the bookend approach is effective with SE-EPI. We have compared the quantitative SE-EPI with GRE-EPI in a series of patients with central nervous system (CNS) tumors. We found that quantitative cerebral blood volume (qCBV) values for SE-EPI and GRE-EPI are in agreement with each other and with historical reference values. A subjective evaluation of image quality showed that image quality in the SE-EPI scans was high and exhibited high interreader agreement. We conclude that measuring qCBV using the bookend technique with SE-EPI images is possible and may be a viable alternative to GRE-EPI in the evaluation of CNS tumors.
Magnetic Resonance Imaging 07/2008; 26(10):1352-9. · 1.99 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Persistent trigeminal arteries are rare and represent a remnant of the fetal carotid-basilar circulation. They typically extend from the internal carotid artery to the basilar artery. An unusual case of a patient with a trigeminal artery originating from the internal carotid artery and terminating as the dominant hemispheric branch of the posterior inferior cerebellar artery is presented.
A 66-year-old woman presented to the emergency department with pulsatile tinnitus, increasing left eye pain, proptosis, conjunctival injection, diplopia, and decreased visual acuity. Conventional contrast-enhanced computed tomographic and magnetic resonance imaging demonstrated findings consistent with a left carotid-cavernous fistula. The patient underwent an emergency diagnostic cerebral angiogram. Besides an indirect carotid-cavernous fistula on the left side, a right-sided persistent trigeminal artery terminating as the dominant hemispheric trunk of the posteroinferior cerebellar artery was incidentally noted. The vermian branch of the right posteroinferior cerebellar artery arose from the ipsilateral vertebral artery, whereas duplicate superior cerebellar arteries supplied the left posteroinferior cerebellar artery region.
The patient was treated for the indirect carotid-cavernous fistula with detachable platinum coils and N-butyl cyanoacrylate, resulting in the resolution of her symptoms.
We report a case of a persistent trigeminal artery supplying only the cerebellar hemisphere. The clinical significance of this anomaly relates to its role in endovascular therapeutic and surgical complications and the paradoxical lesions in the cerebellum that occur as a result of carotid disease. We also discuss the Saltzman classification of persistent trigeminal arteries and their variants.
Neurosurgery 04/2008; 62(3):E746-8; discussion E746-8. · 2.79 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The authors report a unique case of subarachnoid hemorrhage caused by a traumatic pseudoaneurysm of the ophthalmic artery, which was successfully treated with coil embolization. Clinical and imaging features, as well as the relevant literature, are described.
Journal of Neurosurgery 12/2007; 107(5):1043-6. · 2.96 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Vertebroplasty and kyphoplasty are percutaneous techniques developed over the past 20 years to treat vertebral hemangiomas, osteoporotic compression fractures, and osteolytic tumors of the spine. In carefully selected patients, these procedures have led to the cessation or significant reduction in pain in 80 to 90% of patients. In this article, we review the indications and contraindications of these procedures, appropriate patient selection and evaluation, the technique, outcomes, and the potential complications of this form of therapy when performed for the alleviation of pain for osteolytic tumors of the spine.
Seminars in Interventional Radiology 12/2007; 24(4):409-18.
-
[show abstract]
[hide abstract]
ABSTRACT: Child abuse is often suspected based on particular patterns of injury. We report a case of intracranial vertebral artery dissection with subarachnoid hemorrhage (SAH) in a 3-month-old boy following child abuse. The mechanisms of injury and the clinical and imaging findings are discussed. This particular pattern of injury has rarely been reported in association with child abuse. We hope to raise physician awareness of child abuse when faced with these imaging findings.
Pediatric Radiology 07/2007; 37(6):600-2. · 1.67 Impact Factor
-
Journal of Vascular and Interventional Radiology 06/2007; 18(5):692-4. · 2.08 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Limb shaking Transient Ischemic Attack is a rare manifestation of carotid-occlusive disease. The symptoms usually point towards a seizure like activity and misdiagnosed as focal seizures. On careful history the rhythmic seizure like activity reveals no Jacksonian march mainly precipitated by maneuvers which lead to carotid compression. We here present a case of an elderly gentleman who was initially worked up as suffering from epileptic discharge and then later on found to have carotid occlusion.
Elderly gentleman presented with symptoms of rhythmic jerky movements of the left arm and both the lower limbs. Clinical suspicion of focal epilepsy was made and EEG, MRI-Brain with MRA were done. EEG and MRI-Brain revealed normal findings but the MRA revealed complete occlusion of right internal carotid artery. On a follow-up visit jerky movements of the left arm were precipitated by hyperextension and a tremor of 3-4 Hz was revealed. Based on this the diagnosis of low flow TIA was made the patient was treated conservatively with adjustment of his anti-hypertensive and anti-platelet medications.
Diagnosis of limb-shaking TIA is important and should be differentiated from other disorders presenting as tremors. Timely diagnosis is important as these patients are shown to benefit from reperfusion procedures either surgical or radiological reducing their risk of stroke.
BMC Neurology 02/2006; 6:5. · 2.17 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Abstract
Background
Limb shaking Transient Ischemic Attack is a rare manifestation of carotid-occlusive disease. The symptoms usually point towards a seizure like activity and misdiagnosed as focal seizures. On careful history the rhythmic seizure like activity reveals no Jacksonian march mainly precipitated by maneuvers which lead to carotid compression. We here present a case of an elderly gentleman who was initially worked up as suffering from epileptic discharge and then later on found to have carotid occlusion.
Case presentation
Elderly gentleman presented with symptoms of rhythmic jerky movements of the left arm and both the lower limbs. Clinical suspicion of focal epilepsy was made and EEG, MRI-Brain with MRA were done. EEG and MRI-Brain revealed normal findings but the MRA revealed complete occlusion of right internal carotid artery. On a follow-up visit jerky movements of the left arm were precipitated by hyperextension and a tremor of 3–4 Hz was revealed. Based on this the diagnosis of low flow TIA was made the patient was treated conservatively with adjustment of his anti-hypertensive and anti-platelet medications.
Conclusion
Diagnosis of limb-shaking TIA is important and should be differentiated from other disorders presenting as tremors. Timely diagnosis is important as these patients are shown to benefit from reperfusion procedures either surgical or radiological reducing their risk of stroke.
BMC Neurology. 01/2006;
-
[show abstract]
[hide abstract]
ABSTRACT: This study was conducted to get an insight into the knowledge, attitude, and practices of the people of Pakistan regarding organ donation (OD), and to understand the various factors that influence these. Systematic sampling was used to generate a sample size of 357. Data collection was carried out via a questionnaire in the outpatient units of our hospital. All kinds of medical and surgical patients were interviewed. Knowledge of ODs that occur in Pakistan and the rest of the world was found to be 65.5 and 72.8%, respectively. The percentage of those willing to donate their organ/s was 59.9%. Knowledge of OD was significantly associated with education and socioeconomic status. Willingness to donate had a significant association with gender. It also had a moderate association with education and socioeconomic status. Awareness of OD and the knowledge that OD can save lives was also significantly associated with the willingness to donate.
Artificial Organs 12/2005; 29(11):899-905. · 2.00 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Adverse food reactions are a challenge for physicians. As the prevalence of this condition rises, it is important that paediatricians and other health care professionals adeptly diagnose this condition. We begin by discussing the relevant points in history and physical examination, then we discuss the recent effective diagnostic tests and techniques available for doctors and patients, along with several management options. Over the last decade, there have been major advancements in this field and novel mechanisms have been proposed which efficiently modulate immune mechanisms involved. Although results are only preliminary, they do however, indicate a promising future for patients with food allergies.
Journal of the Pakistan Medical Association 11/2005; 55(10):458-62.
-
[show abstract]
[hide abstract]
ABSTRACT: Chiari I malformation, a congenital disorder involving downward displacement of the cerebellar tonsils through the foramen magnum, is often treated surgically by performing suboccipital craniectomy and C-1 laminectomy. The authors report two cases in which fracture of the anterior atlantal arch occurred during the postoperative period following Chiari I decompression and C-1 laminectomy causing significant neck pain. The findings indicate that interruption of the integrity of the posterior arch of C-1, iatrogenically or otherwise, confers increased risk of anterior arch fracture. A C-1 fracture should therefore be considered in the differential diagnosis of posterior cervical pain in patients who have previously undergone decompression for Chiari I malformation.
Journal of Neurosurgery Spine 08/2004; 1(1):137-40. · 1.53 Impact Factor
