Assessment of the normal pediatric pineal gland - MR findings of a single centre; A retrospective study.

OBJECTIVE: To analyse the size and morphology of the normal pineal gland in the paediatric age group using magnetic resonance imaging. METHODS: The retrospective study was conducted at the Aga Khan University Hospital, Karachi, and comprised data of patients aged <18 years who had magnetic resonance imaging done between 2007 and 2017. Pineal size was estimated measuring its largest anteroposterior and supero-inferior diameters on sagittal T2-weighted sequences on any slice with maximal diameter. The width of pineal gland was measured on axial or coronal T2 sequences. The volume, morphology and enhancement patterns of the gland were also assessed. Data was analysed using SPSS 21. RESULTS: Of the 200 patients, 116(58%) were males and 84(42%) were females. The overall mean age was 7.8±5.5 years. The mean anteroposterior dimension was 4.85±1.46mm, height 3.31±0.95mm, width 4.16±1.19, and volume 39.54±38.12 mm3. Mean size of cyst was 2.77±1.4mm (range: 1.2-7.5mm). No significant differences in the pattern of enhancement were found in different age groups (p>0.05). CONCLUSIONS: Comprehensive knowledge of the size of the typical pineal organ is useful for radiologists in the identification of pineal gland anomalies and the exclusion of neoplastic lesions.

Carotid intima media thickness evaluation by ultrasound comparison amongst healthy, diabetic and hypertensive Pakistani patients.

OBJECTIVE: To compare carotid Intima media thickness and atherosclerosis burden amongst healthy, diabetic and hypertensive Pakistani patients. METHODS: A cross-sectional study was carried out at the Department of radiology and family medicine, Aga Khan University Hospital Karachi from April 2014 to July 2015. Bilateral carotid ultrasound was done in 133 healthy adults, 65 hypertensive, 31 type-2 diabetic and 37 hypertensive with type-2 diabetes patients. Normal adults were matched for age and gender. Mean intimal media thickness was measured for common and internal carotid arteries. Presence or absence of atherosclerotic plaque was also identified. Height, weight, ethnicity, socioeconomic status and other risk factors were also assessed. Ultrasound findings were compared between healthy and diseased patients through statistical tests. RESULTS: A total of 266 patients participated (Controls=133, Hypertensive=65, Diabetic=31, and Diabetes with Hypertension=37). There was no significant difference in the baseline characteristics between the four patients' groups for age (p>0.05) and gender (p>0.05). The mean carotid intima media thickenss of right common carotid artery was significantly higher in patients with diabetes along with hypertension as compared to the control group (p=0.03). For (RICA) Right Internal Carotid Artery, (LCCA) Left Common Carotid Artery and (LICA) Left Internal Carotid Artery, there was a significantly higher thickness among patients with hypertension as compared to the control group with p=0.011, p=0.002, and p=0.039 respectively. CONCLUSIONS: Increased CIMT is most likely associated with underlying chronic diseases. Ultrasound is a non-invasive, easily available and useful modality for early detection and prevention of vascular atherosclerosis.

Intratumoral pseudoaneurysms in hepatocellular carcinoma: do they occur de novo without any prior intervention? A tertiary care center experience of 6 years.

BACKGROUND: Intratumoural pseudoaneurysms (ITPA) within hepatocellular carcinomas (HCC) usually arise as postprocedural complications of endovascular therapies or surgical procedures. Their de novo presence in HCC without any prior interventions has not been adequately described in medical literature. PURPOSE: To evaluate and quantify the presence of intratumoural pseudoaneurysms (ITPA) within hepatocellular carcinomas (HCC) prior to any intervention. MATERIAL AND METHODS: Retrospective cross-sectional review of 519 patients with HCC at a tertiary care university hospital with the purpose to evaluate and quantify the presence of ITPA present prior to any therapy. Patients' baseline data along with viral marker status, alpha fetoprotein (AFP) levels, imaging findings, and any prior treatment provided were recorded. Multi-detector computed tomography (MDCT) scans of selected patients were reviewed for presence of any ITPA and their incidence was calculated. RESULTS: ITPAs without any prior therapy were found in 5% (25/519) of patients with HCC. Seventeen of 25 (68%) patients had liver cirrhosis while eight of 25 (32%) patients were non-cirrhotic on imaging. Multiple ITPAs were seen in 44% (11/25) of patients. Eight percent (2/25) of patients had pseudoaneurysm-associated hemorrhage, 20% (5/25) had lung metastasis, 12% (3/25) had portal vein thrombosis, 8% (2/25) had hepatic vein thrombosis, and 16% (4/25) had peritumoral hematoma. The incidence of de novo ITPAs occurring in patients with HCC without any prior therapy or intervention was 0.24%. CONCLUSION: These cases provide a unique insight into an additional feature of HCC and usefulness of recognizing the ITPAs on imaging studies. Although de novo ITPAs in HCC are uncommon, occurring with an incidence rate of 0.24%, their presence in hypervascular hepatic lesion may point towards the diagnosis of HCC. Additionally, they should be accounted for in management planning as they can lead to complications of rupture and hemorrhage.

Clinical, lifestyle, socioeconomic determinants and rate of asymptomatic intracranial atherosclerosis in stroke free Pakistanis.

BACKGROUND: Intracranial Atherosclerotic Disease (ICAD) is the most frequent etiology of stroke with high prevalence among Asians. Despite this, early determinants of ICAD have not been described from this region. METHODS: The study is an analytical prospective cross-sectional study of 200 adults from Radiology Departments of two diagnostic centers in Karachi. Eligible participants confirmed the absence of stroke symptoms via the Questionnaire for Verifying Stroke Free Status (QVSFS) and underwent an interview covering medical, socio demographic, lifestyle and anthropometric evaluation using locally validated and standardized definitions. Magnetic Resonance Images (MRI) were centrally reviewed to detect ICAD using the criterion used in the Warfarin-Aspirin Symptomatic Intracranial Disease study. The risk factors associated with asymptomatic ICAD are reported along with prevalence ratios. RESULTS: Of the 200 participants, ICAD was found in 34.5% (n = 69) of the participants. Mean age was 37.1 (S.D 15.1) years with 62% younger than 45 years. Self-reported hypertension was found in 26.5% subjects, diabetes in 9%, dyslipidemia in 5% and depression in 60%. Smokeless tobacco (Adjusted PR 3.27 (1.07-6.05)), Western diet, high socioeconomic status (Adjusted PR 2.26 (1.99-5.62)) and dyslipidemia (Adjusted PR 1.88 (1.25-2.21)) had significant associations with ICAD after multivariable analysis. Age, gender, diabetes, hypertension, depression and physical activity did not have a significant association. CONCLUSION: ICAD was found on MRI in one in three asymptomatic Pakistanis and was associated with modifiable risks. Initiatives targeting primary prevention may be able to decrease the burden of disease caused by stroke due to ICAD. STUDY REGISTRATION NUMBER: NCT02072876 2/25/2014.

Whole body simultaneous PET/MRI: one-stop-shop?

Beginning of this century is hallmarked by arrival of hybrid imaging PET/CT (positron emission tomography/computerized tomography) which has become a standard of care primarily in oncology in a short span of time. Continuous research and development by industry and academia for exploiting the excellent soft tissue contrast, spectroscopy and precise measurement of various functional parameters by magnetic resonance imaging (MRI) with PET has resulted in emergence of whole body PET/MRI. It is expected this new hybrid modality would be warmly welcomed due to high magnitude of functional and morphostructural information at molecular level with low radiation dose which is indeed a point of concern for young and paediatric population. This short technical report for nuclear medicine readers will focus upon the various configuration and acquisition sequences of PET/MRI, attenuation correction and clinical applications of whole body simultaneous PET/MRI.

Magnetic resonance spectroscopy of enhancing cerebral lesions: analysis of 78 histopathology proven cases.

OBJECTIVES: To investigate the efficacy of magnetic resonance spectroscopy in differentiating various types of neoplastic and non-neoplastic enhancing cerebral lesions. METHODS: The prospective study was conducted from January 2007 to December 2009 at the Department of Radiology, Aga Khan University Hospital, Karachi. All patients with enhancing brain lesions on magnetic resonance imaging who underwent magnetic resonance spectroscopy and a biopsy with histopathological analysis were included in study. The lesions were categorised into neoplastic and non-neoplastic lesions on the basis of spectroscopy findings. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of magnetic resonance spectroscopy were calculated. Predicted probabilities were computed and comparison of median values of metabolites and their ratios was analysed using non-parametric Mann Whitney U test to differentiate between neoplastic and non-neoplastic lesions. RESULTS: Of the 102 patients enrolled, 78 (76.5%) comprised the final study sample. There were 53 (68%) male and 25 (32%) female patients with an overall mean age of 40.21 ± 17.69 years (range: 4-76 years). The mean overall size of the lesion was 4.01 ± 1.79 cm, and 61(78%) lesions were neoplastic and 17 (22%) were non-neoplastic. The sensitivity, specificity, positive predictive value and negative predictive value and diagnostic accuracy of magnetic resonance spectroscopy in differentiating neoplastic and non-neoplastic lesions were 90.16%, 64.70%, 90.16%, 64.70% and 78.20% respectively. A cut-off value of 2.55 of Choline/N-Acetyl Aspartate ratio depicted sensitivity of 70% in differentiating the lesions. CONCLUSION: Magnetic resonance spectroscopy is a highly sensitive technique in addition to conventional magnetic resonance imaging in characterising and differentiating between neoplastic and non-neoplastic cerebral lesions.

Prevalence of metabolic syndrome and its association with CT-based central adiposity measures: a cross-sectional study at a tertiary care hospital in Pakistan.

OBJECTIVES: To assess the prevalence of metabolic syndrome (MS) and association of central obesity measures such as body mass index (BMI), visceral fat adiposity (VFA) and superficial fat adiposity (SFA) with MS, diabetes (DM) and hypertension (HTN). DESIGN: Cross-sectional study design. SETTING: Tertiary care hospital in Pakistan. PARTICIPANTS: 165 participants. There were 124 male participants and 41 female participants of Pakistani population. All participants above 18 years, who had unenhanced CT abdomen examination and relevant blood workup, were included. Patients with a known clinical history of coronary artery disease, HTN and DM as well as pregnant patients were excluded. INTERVENTIONS: VFA and SFA were estimated, at the level of the umbilicus. Data of BMI, MS, DM and HTN were extracted from patient files. Data for MS, DM and HTN were recorded as binary variables. OUTCOME MEASURES: The primary outcome measures were the prevalence of MS and the association of MS, DM and HTN with gender, VFA, SFA and BMI. P value of <0.05 was taken as significant with CI of 95%. RESULTS: The prevalence of MS was 29.7%. There was a significant association of MS, DM and HTN with VFA, SFA and BMI. In gender-based analysis 48.7% of the female participants had MS. In subset analysis, 47% of male subjects in the third tertile of VFA revealed significant association with MS (p value <0.05) while only 32.7% of subjects in the obesity category of BMI had MS. SFA revealed a significant association with DM only (p value <0.5). CONCLUSION: In conclusion, VFA shows a significant association with MS, DM and HTN. Considering these results, further studies with a larger sample size are warranted to generate gender-based cut-offs for VFA for obesity screening purposes.

Hirayama disease, a rare cause of posture related cord compression: a case report from radiological perspective.

Hirayama Disease is a disease of young adults lying in the age group between twenty to thirty years. It is an extremely uncommon disorder. Its other synonyms are juvenile muscular atrophy of the distal upper extremity (JMADUE) or monomelic amyotrophy (MMA). A previously healthy 25-year-old man presented with gradually increasing weakness in both hands for the past few years. There was neither history of trauma nor family history of neuromuscular disease. MRI was advised. Routine cervical sagittal MR images (Non-flexion or extension) revealed cord flattening and atrophy at C5 to C7 levels.There was evidence of syrinx. Flexion MRI was performed later on. Midline sagittal T1- and T2-weighted images of the cervical spine showed anterior displacement of the cervical cord with marked flattening of cord. The patient was advised to modify his posture, avoid flexion and to apply cervical collar. Physiotherapy was started to improve the tone of muscles. In case of deterioration of symptoms he was advised to consult for surgery. The purpose of this case report is to show the importance of dynamic scan in symptomatic patients especially in their second or third decade with progressive upper limb weakness. Mostly the scanning in neutral posture does not reveal any significant cord compression. Similarly a normal looking thecal sac with preserved anterior and posterior thecal sleeves without disc disease dramatically changes on change of posture. This case shows the importance of dynamic scanning in symptomatic patients with progressive upper limb weakness and with no obvious cause of the cord changes on routine MR images. Cervical collar, physiotherapy and in resistant cases surgery is recommended for management.

Amiodarone therapy: don't forget thyroid.

Amiodarone is an effective anti-arrhythmic agent for control of various life threatening ventricular tachyarrhythmias but may give Various side effects. Clinically relevant thyroid dysfunction is not uncommon during amiodarone therapy and is caused by iodide excess and inhibition of deiodinase activity. Amiodarone induced thyroid dysfunction varies from asymptomatic variation in thyroid function to clinically overt hypothyroidism and thyrotoxicosis. Prolonged elimination and half life and associated complications warrant for rational prescribing and long term follow up.

Atypical Imaging Findings in "Central Nervous System Varicella Zoster Virus Vasculopathy Sine Herpete".

Varicella-zoster virus (VZV) infection is notorious for central nervous system involvement, the spectrum of which encompasses vasculopathic manifestations as well. Central nervous system VZV vasculopathy (CVV) most commonly manifests as ischemic strokes or TIA, even though other less common modes of presentation are also well documented in the literature. The pathophysiological mechanism is primarily attributed to active virus infection in the blood vessels secondary to decline in varicella-specific cell-mediated immunity. More than one-third of those with CVV do not have preceding skin lesions of zoster. Hence, a high index of clinical suspicion should be entertained in the appropriate clinical scenario. We hereby describe the case of a 40-year-old lady with systemic lupus erythematosus on long-term oral steroids who presented with acute ischemic stroke involving the right PCA territory, with asymptomatic chronic infarcts in the left MCA. Further evaluation revealed concentric vessel enhancement involving right PCA on high-resolution MR vessel wall imaging with the "Moya-Moya" phenomenon on the left supraclinoid ICA/MCA segment. CSF showed mononuclear pleocytosis with a hemorrhagic component, along with positive VZV DNA PCR. A diagnosis of "CNS VZV Vasculopathy sine herpete" was made and the patient was initiated on appropriate management.

Ultrasound biosafety during pregnancy: what do operators know in the developing world?: national survey findings from pakistan.

OBJECTIVES: The purpose of this study was to evaluate the knowledge and attitudes of ultrasound users toward safety aspects during routine obstetric examinations. METHODS: A self-administered questionnaire was given to all registered participants of the 10th Annual International Radiological Conference in Karachi, Pakistan. RESULTS: A total of 306 participants completed the questionnaire (response rate, 70%), including 170 consultant radiologists (55%), 90 radiology residents (30%), 31 sonographers (10%), and 15 others (5%). The mean sonography experience of the end users ± SD was 5.1 ± 5 years. Around half of the participants (45.5%) reported that there should be limitations on the use of ultrasound during low-risk pregnancy. Overall, safety knowledge was inadequate among the participants. However, those who were concerned about limitations on the use of ultrasound during pregnancy were 2.5 times more likely to be familiar with the mechanical index (P < .001) and 1.8 times more likely to be familiar with the thermal index (P < .001). CONCLUSIONS: Increased training for professionals on safety issues of ultrasound procedures during pregnancy is needed. Furthermore, the concept of the absolute safety of ultrasound procedures without knowledge of safety parameters such as the mechanical and thermal indices needs to be changed, and more clarity is required when defining parameters under which the procedures can be safely performed.

Magnetic resonance spectroscopy in focal brain lesions.

OBJECTIVE: To describe the spectrum of Magnetic Resonance spectroscopy in focal brain lesions and determine its diagnostic accuracy using histopathology as gold standard in differentiating neoplastic and non-neoplastic focal brain lesions. METHODS: The study was conducted in Department of Radiology, Aga Khan University Hospital, Karachi from Dec 2006 till Jan 2009. Fifty three patients found to have focal brain lesions on magnetic resonance imaging (MRI) were included in the study. Magnetic Resonance spectroscopy (MRS) was performed in these focal lesions. These lesions were deemed neoplastic and non-neoplastic on MR Spectrum findings. Correlation of all these findings was done with histopathology obtained in all these patients. Sensitivity, specificity, positive, negative predictive values and diagnostic accuracy of MR Spectroscopy was calculated. Percentage agreement between spectroscopy and histopathology was also calculated using kappa statistics. RESULTS: Increase Choline/creatine and Choline/NAA ratio noted in neoplastic lesions compared to nonneoplastic lesion with significant p-value. MR Spectroscopy has a sensitivity of 93.02%, specificity of 70%, positive predictive value of 93.02%, negative predictive value of 70% and diagnostic accuracy of 88.67% in differentiating neoplastic and non-neoplastic brain lesions. Kappa statistics shows a good agreement between MR Spectroscopy and histopathology (k = 0.630). CONCLUSION: Magnetic Resonance spectroscopy (MRS) is non-invasive sensitive, however, relatively nonspecific modality in differentiating neoplastic and non-neoplastic brain lesions. This modality should be considered as an adjunct to conventional imaging rather than replacement for histopathological evaluation.

Transjugular intrahepatic portosystemic shunt (TIPS); review of initial experience at Aga Khan University Hospital.

OBJECTIVE: To retrospectively assess the therapeutic effectiveness and safety of transjugular intrahepafic portosystemic shunt (TIPS) in patients with portal hypertension related complications. METHODS: Over a period of 7.5 years 19 patients (10 males and 9 females, age range 25-69 years) were referred for TIPS at our radiology department. Thirteen patients suffered from liver cirrhosis while 6 had Budd Chiari syndrome. All patients were evaluated with colour doppler ultrasonography and cross sectional imaging. Shunt procedures were performed under sedation or general anaesthesia through internal jugular approach. Metallic self expandable uncovered stents were placed in 15 patients and covered stent in 1 patient. Follow up of patency was evaluated with ultrasound in majority and by venography in some patients. Safety of the procedure and clinical outcome were analyzed. RESULTS: Indications of procedure included variceal bleeding (n=8), ascites (n=4), ascites and bleeding (n=1) and Budd-Chiari syndrome (n=6). Technical success rate was 84.21%. Complication rate was 10.53%. Three days mortality was 15.79%. Mean primary shunt patency was 306.62 +/- 533 days. During follow-up stent occlusion occurred in 5 patients (31.25%). Four of these patients underwent successful reintervention. Recurrence of symptoms occurred in 68.75% patients. CONCLUSION: TIPS is useful for management of complications of portal hypertension that are refractory to pharmacological and endoscopic treatment, however shunt stenosis or occlusion may cause recurrence of symptoms. Repeated interventions are often required to maintain shunt patency.

Triphasic computed tomography (CT) scan in focal tumoral liver lesions.

OBJECTIVE: To assess the diagnostic accuracy of triphasic spiral CT in differentiating benign from malignant focal tumoral liver lesions. METHODS: The study was conducted in Department of Radiology of Aga Khan University Hospital and Sind Institute of Urology and Transplantation, Karachi from Feb 2006 to Feb 2007. By convenient sampling, 45 patients found to have focal tumoral liver lesions were recruited for one year period and their triphasic CT scans findings were evaluated and later correlated with histopathology. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of triphasic CT scan were calculated. RESULTS: Among 45 patients, 136 liver lesions (11 benign and 125 malignant) were detected with the help of different enhancement patterns. Out of these, 37(82.2%) patients had malignant while 8 (17.8%) had benign lesions. On later histopathological examination, 35 (77.8%) of the total 45 cases had malignant lesions while 10 (22.2%) were diagnosed as benign lesions. Based on these results, it could be assessed that triphasic CT Scan has a sensitivity of 100%, specificity of 80%, positive predictive value of 94.5%, negative predictive value of 100% and diagnostic accuracy of 95.5% in differentiating benign from malignant liver lesions. CONCLUSION: Triphasic CT Scan is a good non-invasive tool in characterizing and differentiating benign from malignant liver lesions.

Treatment of intracranial aneurysms using detachable coils; initial results at a university hospital in Pakistan.

OBJECTIVE: To evaluate the technical success, safety and outcome of endovascular coiling procedure in intracranial aneurysms. METHODS: From April 2003 to April 2009, 43 patients (23 males and 20 females), age range 11 to 70 years, mean age 46.67 +/- 11.57 years were treated for intracranial aneurysms by detachable coil deployment at Radiology Department of Aga Khan University Hospital. Aneurysm rupture with subarachnoid haemorrhage was the cause of presentation in 39 patients while 4 patients were diagnosed with un-ruptured aneurysms. At time of presentation, grading of subarachnoid haemorrhage was done according to Hunt and Hess grading system. Eleven patients presented with Grade I haemorrhage, other 11 presented with grade II haemorrhage, 8 patients had grade III haemorrhage and 9 patients had grade IV haemorrhage. Preliminary diagnostic workup was performed by cross sectional imaging, CT angiography or digital substraction angiography. Coiling procedures were performed under general anaesthesia through femoral artery approach. Detachable platinum coils were densely packed in all aneurysms by endovascular technique. Patient files and radiology reports were retrospectively reviewed. Technical success and safety of the procedure were analyzed. Modified Rankin Score was used to determine clinical outcome. Score 0-2 represented good outcome, score 3-5: dependency (Can not attend own bodily needs and carry out daily activities without assistance) and score 6: death. RESULTS: Aneurysm size ranged from 3mm - 22mm (mean size 8 mm +/- 4). 74.4% aneurysms had narrow necks while 25.6% aneurysms were wide necked. Most common aneurysm site was anterior communicating artery. Technical success rate for endovascular intracranial aneurysm coiling was 95.3% (n = 41). Major complication rate was 11.6 % (n = 5). Mortality rate was 2.3% (n = 1). 78% patients showed good clinical outcome after coiling including 4 patients with un ruptured aneurysms (n = 32). CONCLUSION: Results of endovascular aneurysm coiling at our center showed high technical success rate (95.3%) and good short term clinical outcome in 78% patients.

Frequency and outcome of carotid atheromatous disease in patients with stroke in Pakistan.

BACKGROUND AND PURPOSE: Limited data exist on the frequency and outcome of carotid artery disease in Pakistan. Such information would help guide the usefulness of screening for the condition in this low-middle income health care setting. METHODS: A prospective, descriptive study was conducted among 3 large teaching hospitals in Karachi, Pakistan. Patients referred for carotid Doppler ultrasound examination were included if they had experienced a stroke or TIA within the previous month. The severity and morphology of carotid disease were characterized by trained technicians using standardized criteria. Demographic and risk factor data were collected at baseline, and the outcome of patients was assessed at least 6 months later. RESULTS: A total of 672 patients underwent bilateral carotid Doppler ultrasound (1344 carotid examinations). The findings revealed 0% to 50% stenosis in 526 (78%), 51% to 69% stenosis in 57 (8%), 70% to 99% stenosis in 82 (12%), and total occlusion in 7 patients (1%). Potentially surgically correctable disease, defined as 70% to 99% carotid artery stenosis, was present in only 79 (12%) patients, of whom 47 (60%) were ipsilateral symptomatic, 15 (20%) asymptomatic, and 17 (20%) had status unknown. Outcome information at >or=6 months follow-up was available for 36 of the 47 (76%) surgically correctable and only 4 of these patients (12%) had undergone surgical or radiological intervention (carotid endarterectomy in 3 patients and carotid stenting in 1 patient). CONCLUSIONS: The frequency of carotid artery disease of at least moderate severity is very low in patients with recent stroke or TIA and there is low utilization of high-cost, carotid intervention procedures in Pakistan. These data raise questions regarding the applicability and cost-effectiveness of routine carotid ultrasound screening in our country and similar population in Asia. The local socio-economic and clinical data do not support routine carotid Doppler ultrasound in every patient with stroke and TIA in Pakistan. Studies are warranted to determine predictors of significant carotid artery stenosis in stroke/TIA patients of our country to develop reliable stroke guidelines appropriate for local population.

Perfusion imaging in ischaemic stroke.

Perfusion imaging allows the blood flow to the tissue to be imaged. It is currently widely applied to the management of acute ischaemic stroke. Using either Computerised Tomography or Magnetic Resonance Imaging techniques, perfusion maps can be created in a short enough time to allow their routine use in clinical practice. Perfusion Imaging enables the physician to directly estimate the tissue at risk which can be salvaged with reperfusion, enabling appropriate patient selection. Perfusion imaging however has its limitations which need to be kept in mind when these studies are interpreted. Although perfusion imaging is widely used, the evidence to support its routine use in acute stroke is somewhat sparse and therefore there are no clear cut guidelines as to its role in this context. The work in progress using permeability mapping and molecular imaging techniques will further augment the place of these techniques in the overall management of acute stroke. There are very few centres in Pakistan offering routine perfusion imaging prior to thrombolysis.

Pituitary height on magnetic resonance imaging observation of age and sex related changes.

OBJECTIVE: To establish measurements of selected pituitary parameters in cases with normal pituitary gland in < or = 30 year old selected samples from Karachi. METHODS: A total of 220 subjects of < or = 30 years of age with normal pituitary morphology were evaluated by using T2 weighted Magnetic Resonance (MR) Imaging. Pituitary height (PH) and shape of the superior surface of the gland was observed on midsaggital sections. Data was stratified into six groups on the basis of age and sex to observe the differences. RESULTS: After the second month of life, the pituitary height increased gradually to achieve its peak in the second decade of life in the females (6.3 +/- 1.4 mm, n = 43) and the third decade of life in the males (5.9 +/- 1 mm, n = 41). PH decreased gradually there after. Significant difference was observed in PH in different age groups in both genders. Gland was significantly higher in females than males in the second decade. Higher frequencies of convex superior surface followed the same pattern. CONCLUSION: This study provided the reference values for the Pituitary height and the shape of the superior surface of the pituitary gland, which may contribute to establish credible reference values.

Endovascular stenting for carotid artery stenosis: results of local experience at Aga Khan University Hospital, Karachi.

OBJECTIVE: To evaluate the results, complications and initial follow-up of patients after percutaneous stent placement for carotid artery disease. METHODS: A retrospective study was carried out on patients treated with carotid artery stenting at the Radiology Department of Aga Khan University Hospital, Karachi, from September 2002 to December 2005. The patients were selected according to the institutional guidelines for Carotid Angioplasty and stenting. Preliminary angiogram was performed in all patients followed by stent deployment. Distal protection device was used in 12 patients. All patients underwent pre and post procedure independent neurological examinations. Follow-up consisted of serial duplex ultrasonography and clinical assessment. RESULTS: Total of 18 stentings were carried out on 17 patients, with one patient having bilateral carotid stenting. There were 14 males and 3 females with an age range of 13 to 68 years. Technical success rate of stent deployment was 100%. Two patients developed Transient Ischaemic Attack (TIA) with transient monoparesis. One patient had confusion and TIA (Hemiparesis) during the preliminary angiogram before stenting. One patient acquired asystole during the procedure; however, he recovered with resuscitation. Five patients had transient bradycardia and hypotension. All these patients recovered with conservative therapy. No stroke or death occurred in any of our patients who underwent this procedure. CONCLUSION: The initial experience revealed satisfactory results with low morbidity rate.

Hepatic, Periportal, Retroperitoneal, and Mesenteric Neurofibromatosis in von Recklinghausen's Disease.

We present a rare case of histologically proven neurofibromatosis of the liver, hepatic hilum, retroperitoneum, and mesentery. An adult male who had been diagnosed with neurofibromatosis (NF) type 1 underwent a computed tomography (CT) scan for abdominal pain and vomiting. The CT scan showed a large low-attenuating lesion in the region of porta hepatis which was infiltrating along portal tracts into the liver, encasing the major vessels, and extending into the retroperitoneum and mesentery. Based on the radiological findings, a differential diagnosis of plexiform neurofibroma was given, although sarcomatous transformation could not have been entirely excluded from imaging alone. The tumor was subsequently biopsied, and the histopathological analysis confirmed the diagnosis of neurofibroma. This case highlights the importance and diagnostic dilemmas in the presence of this tumor at atypical locations in this disease spectrum.