Angiomyolipoma during pregnancy: A forgotten risk factor for rupture and massive haemorrhage - A case report.

Benign renal lesions are relatively rare. Angiomyolipoma (AML) is the most commonly encountered benign renal lesion. One of the complications of AML is rupture, which results in retroperitoneal haemorrhage with a mortality rate of up to 20%. Pregnancy poses a major risk for the rupture of AML. This is attributed to its hormonal effect, which causes the tumour to grow rapidly during pregnancy. The possibility of AML rupture should be considered when encountering pregnant patients with hypovolemic shock but with normal initial obstetric ultrasound findings. We present a case of a pregnant patient who was admitted with hypovolemic shock and CT scan confirmed rupture of AML.

Levels of PIVKA-II and alpha-fetoprotein in unresectable hepatocellular carcinoma compared to healthy controls and predictive values of both markers with radiological responses after loco-regional interventions.

Background: The significance of the current study was to determine normative levels of PIVKA-II and AFP in patients with unresectable HCC and healthy participants. The second goal was to assess the roles of PIVKA-II and AFP in predicting radiological response after loco-regional therapy. Methods: This prospective cohort study enrolled consecutive samples of HCC patients and healthy controls. Venous blood samples were obtained at baseline and after interventions to determine serum levels of PIVKA-II and AFP using the chemiluminescent microparticle immunoassay method. Radiologic responses were determined based on the WHO criteria. Results: Fifty-four HCC patients (mean age 58.9 years, 49 males) and 40 healthy controls (mean age 33.5 years, 26 males) were recruited. The median serum levels of PIVKA-II and AFP in HCC vs. healthy controls were 988.4 vs. 24.2 mAU/ml and 13.6 vs. 1.7 ng/ml, respectively (both p < 0.001). With ROC curve analysis, the area under the curve (AUC) for PIVKA-II was 0.95 95% CI [0.90-0.99], and for AFP it was 0.98, 95% CI [0.95-1.0]). The cut-off value for PIVKA-II was 41.4 mAU/ml, and AFP was 4.8 ng/ml. PIVKA-II levels correlated significantly with radiological responses (r = 0.64, p = 0.02) but not AFP (r = 0.09, p = 0.2). Conclusion: PIVKA-II and AFP levels are distinctive between unresectable HCC and healthy controls. However, PIVKA-II, not AFP, can predict the radiological response after loco-regional therapy.

Regional cerebral blood perfusion changes in chronic stroke survivors as potential brain correlates of the functional outcome following gamified home-based rehabilitation (IntelliRehab)-a pilot study.

BACKGROUND: Hospital-based stroke rehabilitation for stroke survivors in developing countries may be limited by staffing ratios and length of stay that could hamper recovery potential. Thus, a home-based, gamified rehabilitation system (i.e., IntelliRehab) was tested for its ability to increase cerebral blood flow (CBF), and the secondary impact of changes on the upper limb motor function and functional outcomes. OBJECTIVE: To explore the effect of IntelliRehab on CBF in chronic stroke patients and its correlation with the upper limb motor function. METHODS: Two-dimensional pulsed Arterial Spin Labelling (2D-pASL) was used to obtain CBF images of stable, chronic stroke subjects (n = 8) over 3-months intervention period. CBF alterations were mapped, and the detected differences were marked as regions of interest. Motor functions represented by Fugl-Meyer Upper Extremity Assessment (FMA) and Stroke Impact Scale (SIS) were used to assess the primary and secondary outcomes, respectively. RESULTS: Regional CBF were significantly increased in right inferior temporal gyrus and left superior temporal white matter after 1-month (p = 0.044) and 3-months (p = 0.01) of rehabilitation, respectively. However, regional CBF in left middle fronto-orbital gyrus significantly declined after 1-month of rehabilitation (p = 0.012). Moreover, SIS-Q7 and FMA scores significantly increased after 1-month and 3-months of rehabilitation. There were no significant correlations, however, between CBF changes and upper limb motor function. CONCLUSIONS: Participants demonstrated improved motor functions, supporting the benefit of using IntelliRehab as a tool for home-based rehabilitation. However, within-participant improvements may have limited potential that suggests the need for a timely administration of IntelliRehab to get the maximum capacity of improvement.

Skull Base Primary Ewing Sarcoma: A Radiological Experience of a Rare Disease in an Atypical Location.

BACKGROUND Ewing sarcoma and primitive neuroectodermal tumor are rare tumors grouped under the spectrum of the Ewing sarcoma family of tumors. These highly malignant tumors involve the bones and commonly occur in children. Ewing sarcoma of the skull bone accounts for only 1% of all Ewing sarcomas, with primary skull base Ewing sarcoma occurring in less than 1% of cases. We present a case of skull base Ewing sarcoma with complete symptom recovery and near-total radiological resolution. CASE REPORT A 4-year-old girl initially presented with a 2-month history of vomiting, poor oral intake, weight loss, and gradual visual deterioration followed by acute symptoms of fever, breathing difficulties, and seizure. Initial computed tomography and magnetic resonance imaging of the brain displayed a large sinonasal mass with extensive regional infiltration and bony destruction and no evidence of distant metastasis. A transnasal biopsy was taken. The histopathology result revealed features of skull base Ewing sarcoma. The child was given a combination of radiotherapy and chemotherapy, to which she responded well, with a minimal residual tumor. CONCLUSIONS Skull base Ewing sarcoma is a rare entity, presenting a challenge to the reporting radiologists. Differential diagnoses of esthesioneuroblastoma, olfactory neuroepithelioma, and, more commonly, sinonasal carcinoma can be misleading since they have similar radiological appearances to skull base Ewing sarcoma, which differs in treatment regimen and prognosis. Therefore, a combination of histopathological appearance, radiographic findings, and clinical correlation is important to determine the correct diagnosis, establish the appropriate treatment regime, and improve the patient's survival.

Percutaneous nephrostomy versus retrograde ureteral stenting for acute upper obstructive uropathy: a systematic review and meta-analysis.

Acute obstructive uropathy is associated with significant morbidity among patients with any condition that leads to urinary tract obstruction. Immediate urinary diversion is necessary to prevent further damage to the kidneys. In many centres, the two main treatment options include percutaneous nephrostomy (PCN) and retrograde ureteral stenting (RUS). The purpose of this study if to compare the efficacy and safety of PCN and RUS for the treatment of acute obstructive uropathy. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, CINAHL, EMBASE, the World Health Organisation International Clinical Trials Registry Platform and ClinicalTrials.gov. We also searched the reference lists of included studies to identify any additional trials. We included randomised controlled trials and controlled clinical trials comparing the outcomes of clinical improvement (septic parameters), hospitalisation duration, quality of life, urinary-related symptoms, failure rates, post-procedural pain [measured using a visual analogue scale (VAS)] and analgesics use. We conducted statistical analyses using random effects models and expressed the results as risk ratio (RR) and risk difference (RD) for dichotomous outcomes and mean difference (MD) for continuous outcomes, with 95% confidence intervals (CIs). Seven trials were identified that included 667 patients. Meta-analysis of the data revealed no difference in the two methods in improvement of septic parameters, quality of life, failure rates, post-procedural pain (VAS), or analgesics use. Patients receiving PCN had lower rates of haematuria and dysuria post-operatively and longer hospitalisation duration than those receiving RUS. PCN and RUS are effective for the decompression of an obstructed urinary system, with no significant difference in most outcomes. However, PCN is preferable to RUS because of its reduced impact on the patient's post-operative quality of life due to haematuria and dysuria, although it is associated with slightly longer hospitalisation duration.

An overview of fractional anisotropy as a reliable quantitative measurement for the corticospinal tract (CST) integrity in correlation with a Fugl-Meyer assessment in stroke rehabilitation.

[Purpose] Understanding the essential mechanisms in post-stroke recovery not only provides important basic insights into brain function and plasticity but can also guide the development of new therapeutic approaches for stroke patients. This review aims to give an overview of how various variables of Magnetic Resonance-Diffusion Tensor Imaging (MR-DTI) metrics of fractional anisotropy (FA) can be used as a reliable quantitative measurement and indicator of corticospinal tract (CST) changes, particularly in relation to functional motor outcome correlation with a Fugl-Meyer assessment in stroke rehabilitation. [Methods] PubMed electronic database was searched for the relevant literature, using key words of diffusion tensor imaging (dti), corticospinal tract, and stroke. [Results] We reviewed the role of FA in monitoring CST remodeling and its role of predicting motor recovery after stroke. We also discussed the mechanism of CST remodeling and its modulation from the value of FA and FMA-UE. [Conclusion] Heterogeneity of post-stroke brain disorganization and motor impairment is a recognized challenge in the development of accurate indicators of CST integrity. DTI-based FA measurements offer a reliable and evidence-based indicator for CST integrity that would aid in predicting motor recovery within the context of stroke rehabilitation.

Computed Tomographic Morphometric Analysis of C1 and C2 for Lamina Cross Screw Placement in Malay Ethnicity.

STUDY DESIGN: This is an observational study of computed tomography (CT) data. PURPOSE: The C1 and C2 laminas in the Malaysian Malay population were analyzed for the feasibility of fitting 3.5-mm laminar screws in a cross configuration. OVERVIEW OF LITERATURE: Morphometric analysis of the C1 and C2 laminas has been performed for various populations but not for the Malaysian Malay population. METHODS: A total of 330 CT cervical images were measured to establish the bicortical diameter of the C1 and C2 laminas as well as their height and length. The C1 posterior tubercle bicortical diameter and height were also determined from these images. All parameters were measured up to 0.1 mm, and statistical analysis was performed using IBM SPSS Statistics ver. 24.0 (IBM Corp., Armonk, NY, USA). An independent t -test and the Pearson chi-square test were used to determine the mean difference and screw acceptance. RESULTS: The means of the C1 lamina measurements were 5.79±1.19 mm in diameter, 9.76±1.51 mm in height, and 20.70±1.86 mm in length. The means of the measurements of the posterior tubercle were 7.20±1.88 mm in diameter and 10.51±1.68 mm in height. The means of the C2 lamina measurements were 5.74±1.31 mm in diameter, 11.76±1.69 mm in height, and 24.96±2.56 mm in length. Overall 65.5% of C1 and 80.3% of C2 laminas are able to accept 3.5-mm screws in a cross configuration. Screw acceptability is similar between the right and left sides (p >0.05). However, males have a higher screw acceptability compared with females (p <0.05), except for the C2 left lamina. CONCLUSIONS: It is feasible to insert a 3.5-mm screw in a cross configuration in the C1 and C2 laminas of the Malaysian Malay population, especially in males. However, a CT scan should be performed prior to the operation to determine screw acceptability and to estimate screw sizes.

Comparison of Vitamin D Levels, Bone Metabolic Marker Levels, and Bone Mineral Density among Patients with Thyroid Disease: A Cross-Sectional Study.

Thyroid hormones have a catabolic effect on bone homeostasis. Hence, this study aimed to evaluate serum vitamin D, calcium, and phosphate and bone marker levels and bone mineral density (BMD) among patients with different thyroid diseases. This cross-sectional study included patients with underlying thyroid diseases (n = 64, hyperthyroid; n = 53 euthyroid; n = 18, hypothyroid) and healthy controls (n = 64). BMD was assessed using z-score and left hip and lumbar bone density (g/cm2). The results showed that the mean serum vitamin D Levels of all groups was low (<50 nmol/L). Thyroid patients had higher serum vitamin D levels than healthy controls. All groups had normal serum calcium and phosphate levels. The carboxy terminal collagen crosslink and procollagen type I N-terminal propeptide levels were high in hyperthyroid patients and low in hypothyroid patients. The z-score for hip and spine did not significantly differ between thyroid patients and control groups. The hip bone density was remarkably low in the hyperthyroid group. In conclusion, this study showed no correlation between serum 25(OH)D levels and thyroid diseases. The bone markers showed a difference between thyroid groups with no significant difference in BMD.

Volumetric MRI-guided, high-intensity focused ultrasound ablation of uterine leiomyomas: ASEAN preliminary experience.

PURPOSE: We sought to present our preliminary experience on the effectiveness and safety of magnetic resonance imaging (MRI)-guided, high-intensity focused ultrasound (HIFU) therapy using a volumetric ablation technique in the treatment of Association of Asian Nations (ASEAN) patients with symptomatic uterine leiomyomas. METHODS: This study included 33 women who underwent HIFU treatment. Tissue characteristics of leiomyomas were assessed based on T2- and T1-weighted MRI. The immediate nonperfused volume (NPV) ratio and the treatment effectiveness of MRI-guided HIFU on the basis of the degrees of volume reduction and improvement in transformed symptom severity score (SSS) were assessed. RESULTS: The median immediate NPV ratio was 89.8%. Additionally, the median acoustic sonication power and HIFU treatment durations were 150 W and 125 min, respectively. At six-month follow-up, the median leiomyoma volume had decreased from 139 mL at baseline to 84 mL and the median transformed SSS had decreased from 56.2 at baseline to 18.8. No major adverse events were observed. CONCLUSION: The preliminary results demonstrated that volumetric MRI-guided HIFU therapy for the treatment of symptomatic leiomyomas in ASEAN patients appears to be clinically acceptable with regard to treatment effectiveness and safety.

Postoperative major surgery patients developing silent deep vein thrombosis: A prospective observational study.

Surgical patients are at high risk for developing deep vein thrombosis (DVT). There are many reports concerning DVT, but little is known about silent deep vein thrombosis (sDVT). This study aimed to determine the incidence of sDVT. Secondary objective is to identify the associated factors for the use of DVT prophylaxis and Caprini risk scores among major surgery patients. This prospective observational study involved postoperative surgical patients who are at risk of developing sDVT. The Caprini risk-assessment scores were calculated, and each subject had a preoperative and postoperative compression ultrasound complemented by duplex venous ultrasonography of deep venous system. No patient from the study experienced sDVT. There were significant associations between Caprini risk score group (odds ratio, 8.16; 95% confidence interval [CI], 1.01-68.74; P = .016) and the use of central venous catheter (odds ratio, 6.34; 95% CI, 1.62-24.80; P = .008) with DVT prophylaxis. Interestingly, the use of central venous catheter resulted in more than four-point increment of Caprini risk scores (mean increment, 4.19; 95% CI, 3.16-5.21; P < .001). Besides that, age was also significantly associated with Caprini risk scores (ß coefficient, 0.06; 95% CI, 0.02-0.11). Result from our study shows that the sDVT was nonexistent in this study setting. High-Caprini risk score group and the presence of central venous catheter were the significant predictor factors for the use of DVT prophylaxis. Significant predictor factors for Caprini risk scores were age and the presence of central venous catheter.

Beating the odds: a rare case of supracardiac total anomalous pulmonary venous return (TAPVR) in an adult patient.

Total anomalous pulmonary venous return (TAPVR) is a rare congenital heart defect, and patients are usually symptomatic at a very young age. Survival to adulthood without surgical correction is extremely rare. We report a 33-year-old woman with a heart murmur and a history of a successful pregnancy. Echocardiogram revealed a large atrial septal defect with suspicious pulmonary vein anomaly. Chest radiograph demonstrated classical 'snowman' configuration. Cardiac catheterisation was consistent with anomalous pulmonary venous drainage. Cardiac CT confirmed supracardiac TAPVR, whereby all the pulmonary veins drain into the anomalous vein and finally to the superior vena cava. She remained asymptomatic and underwent a successful surgical repair.

The morphometric study of l3-L4 and L4-L5 lumbar spine in Asian population using magnetic resonance imaging: feasibility analysis for transpsoas lumbar interbody fusion.

STUDY DESIGN: Cross-sectional study on the measurement of relevant magnetic resonance imaging parameters in 100 patients presented for lumbar spine assessment. OBJECTIVE: To determine anatomical position of lumbar plexus and major blood vessels in relation to vertebral body and anterior edge of psoas muscle at L3-L4 and L4-L5 and to define the safe working zone for transpsoas approach for lumbar fusion. SUMMARY OF BACKGROUND DATA: Lateral transpsoas lumbar interbody fusion has been shown to be safe and provides alternative for lumbar fusion. However, proximity of neurovascular structures may not allow a safe passage for this procedure in the Asian population. METHODS: Relevant parameters were measured from axial magnetic resonance images and analyzed, including the psoas muscle and vertebrae endplate diameters, lumbar plexus and psoas muscle distance, lumbar plexus and vertebra body distance, and vena cava to the anterior vertebrae body diameters. RESULTS: The mean anteroposterior diameters of the right and left psoas muscle ranged from 44.0 to 58.6 mm and 44.8 to 54.0 mm, respectively. The mean anteroposterior diameters of vertebra endplate of L3, L4, and L5 were 38.2 mm, 39.3 mm, and 41.4 mm, respectively. The mean distance of posterior border of vena cava from the vertebra body was 4.5 mm at L3-L4 and 14.1 mm at L4-L5. CONCLUSION: L3-L4 fusion is feasible at both sides in both sexes; however, at L4-L5 level, the procedure is feasible only on the left side. The safe working zone for transpsoas approach to lumbar spine is significantly narrower at L4-L5 in both sexes. Anterior edge of psoas muscle can be used as a reliable guide to locate lumbar plexus within psoas muscle. LEVEL OF EVIDENCE: N/A.

MR Volumetry of Hippocampus in Normal Adult Malay of Age 50 Years Old and Above.

BACKGROUND: Hippocampal volume is affected by several psychiatric illnesses of old age, as well as by normal aging. It is important to have a normal data in a population to assist in diagnosis. The aim of this study is to determine hippocampal volume in normal Malay people aged 50 years old and older. METHODS: This was a cross-sectional study of the normal Malay population aged 50 to 77 years. We included 43 participants, representing 19 men and 24 women. Magnetic resonance imaging (MRI) was performed using a GE Signa Horizon LX 1.0 Tesla. Oblique coronal images of temporal lobes were obtained and hippocampal volumetry was done manually and normalised with intracranial volume. RESULTS: Mean right and left hippocampal volumes (HCVs) were 3.43 cm³ (SD 0.32) and 3.26 cm³ (SD 0.34), with a significant difference between them (P < 0.001). Total mean HCVs exhibited no significant difference between men and women (P = 0.234). The means of the normalised right and left HCVs were 3.42 cm³ (SD 0.31) and 3.26 cm³ (SD 0.32). CONCLUSION: The mean right and left hippocampal volumes were significantly different in this study. Men had slightly larger mean HCVs but the difference was not statistically significant. It was found that normalisation further reduces the mean volume difference between the genders.

Normalised MRI Volumetry of the Hippocampus among Normal Malay Children and Adolescents.

BACKGROUND: Magnetic resonance imaging (MRI) is a noninvasive method for determining brain morphology and volumetry. Hippocampal volume changes are observed in conjunction with several diseases. This study aimed to determine the normalised volume of the hippocampus in normal Malay children and adolescents. METHODS: This was a cross-sectional study performed from January 2009 to June 2010. Brain and temporal lobe MRI was performed for 81 healthy normal Malay individuals aged 7-18 years. Manual volumetry was performed. The hippocampal volumes were normalised with the total intracranial volume. RESULTS: The original right, left, and total hippocampal volumes (mean and standard deviation) were 3.05 (0.48) cm(3), 2.89 (0.44) cm(3), and 5.94 (0.90) cm(3), respectively. Normalised hippocampal volumes for the right, left, and total volume were 3.05 (0.41) cm(3), 2.89 (0.41) cm(3), and 5.94 (0.79) cm(3), respectively. Pearson's correlation coefficient for the right and left hippocampal volumes with intracranial volume were 0.514 and 0.413, respectively (P < 0.001). Both the original and normalised hippocampal volumes of the right hippocampus were significantly larger than those of the left (P < 0.001). CONCLUSION: This is a data set for the local Malay paediatric population. There was no significant difference between the actual and normalised values of hippocampal volume in our study.

Angioarchitecture of brain arteriovenous malformations and the risk of bleeding: an analysis of patients in northeastern malaysia.

BACKGROUND: Central nervous system arteriovenous malformation (AVM) is a vascular malformation of the brain and involves entanglement of veins and arteries without an intervening capillary bed. Affecting predominantly young male patients, AVM presents with different clinical manifestations namely headache, seizures, neurological deficit and intracranial haemorrhage. The patients who present acutely with intracranial bleeding have a significant morbidity and mortality. The aim is to study the angioarchitecture of brain AVM (BAVM) and determine the risk factors for intracranial bleeding. Ultimately, the goal of the study is to look for the association between volume of haematoma and architecture of BAVM. METHODS: A cross-sectional study of 58 patients was conducted at the Hospital Universiti Sains Malaysia. Data were collected over a period of seven years (2000 to 2007) to look for the association between the angioarchitecture of brain arteriovenous malformations (BAVM), haemodynamics and the natural history and risk of intracranial haemorrhage. RESULTS: BAVM was predominantly found in young male patients in 65.5%. Small nidal size (P-value=0.004), deep location (P-value=0.003) and deep venous drainage (P-value=0.006) were found to be significant factors contributing to intracranial haemorrhage. All patients with coexisting intranidal or prenidal aneurysms presented with intracranial haematoma. CONCLUSION: The angioarchitecture of BAVM like nidal size, deep location and deep venous drainage can predict the risk of intracranial bleeding and can help in the management of high risk patients without any delay. Small sized and deep seated lesions have a diffuse type of intracranial bleed which eventually need more attention to the managing team as diffuse haematoma indicates more insult to brain.

Correlations between subdural empyema and paraclinical as well as clinical parameters amongst urban malay paediatric patients.

Paediatric subdural empyema is frequently seen in developing Asean countries secondary to rinosinusogenic origins. A cross-sectional analysis on the surgical treatment of intracranial subdural empyema in Hospital Kuala Lumpur (HKL), a major referral center, was done in 2004. A total number of 44 children who fulfilled the inclusion criteria were included into this study. The methods of first surgery, volume of empyema on contrasted CT brain, improvement of neurological status, re-surgery, mortality and morbidity, as well as the demographic data such as age, gender, sex, duration of illness, clinical presentation, probable origin of empyema, cultures and follow-up were studied. Chi-square test was performed to determine the association between surgical methods and the survival of the patients, neurological improvement, clearance of empyema on CT brain, re-surgery and long morbidity among the survivors. If the 20% or more of the cells were having expected frequency less than five, then Fisher's Exact test was applied. The level of significance was set at 0.05. SPSS version 12.0 was used for data entry and data analysis. There were 44 patients who were less than 18 years. Their mean age was 5.90 ± 6.01 years. There were 30 males (68.2%) and 14 females (31.8%) involved in the study. Malays were majority with 28 (63.6%) followed by Indian 8 (18.2%), Chinese 5 (11.4%) and others 3 (6.8%). The variables which were under interest were gender, race, headache, vomiting, seizures, sign of meningism, cranial nerve palsy, thickness site of abscess, first surgical treatment, improvement in neurological deficit, clearance of CT and whether re-surgery was necessary. All variables were found not to be associated with Henk W Mauser Score for PISDE grading. Comparison between this urban study and a rural setting study by the same corresponding author in the same period on subdural empyema was done. Common parameters were compared and it was found out that seizures were more prevalent in urban study where the patients are more than one year old (p=0.005). Mortality was much higher in urban study than the rural one (p=0.040). The larger proportion of urban group had volume of abscess less than or equal to 50 ml (p=< 0.001).

Computed tomographic morphometry of thoracic pedicles: safety margin of transpedicular screw fixation in malaysian malay population.

STUDY DESIGN: A cross-sectional study of thoracic pedicle morphometry (T1-T12) of 180 Malaysian Malay patients obtained from computed tomographic scan. OBJECTIVES: To determine the safety margin in the placement of thoracic transpedicular screw in the Malay population. SUMMARY OF THE BACKGROUND DATA: Previous studies have shown a significantly smaller thoracic pedicular parameters in Asians compared with whites. The safety margin in the placement of thoracic transpedicular screw in our population therefore needs to be defined. METHODS: T1-T12 vertebral pedicles were studied in 180 Malay ethnic patients (age range, 18-80 years). The following parameters were studied: transverse outer pedicle diameter, transverse inner pedicle diameter, transverse pedicle angle, chord length, pedicle length, and pedicle cortical thickness. The data obtained were statistically analyzed using Student's t test and ANOVA test. RESULTS: Female patients have significantly smaller dimensions in most of the parameters measured compared with male patients. However, no significant difference was found between age groups. Transverse outer pedicle diameter were widest at T1 (male, 8.42 mm; female, 7.56 mm) and narrowest at T4 (male, 4.56 mm; female, 3.95 mm). Pedicle diameters of less than 5.5 mm were commonly seen at T4 followed by T5, T6, T7, T8, and T9. A significant percentage of patients have an outer diameter of less than 4.5 mm from T4-T7. The medial cortices were 50% thicker than the lateral cortices at most levels. Chord lengths were maximum at T8 and minimum at T1. Transverse pedicle angle were widest at T1 and less than 5 degrees from T7-T12. CONCLUSIONS: The results suggest that the current pedicle screw system is not suitable for the majority of Malay population, especially at midthoracic level. The smaller pedicle measurements in Malays may be attributed to their shorter body built compared with whites.

Computerized tomographic measurement of the cervical pedicles diameter in a Malaysian population and the feasibility for transpedicular fixation.

STUDY DESIGN: The cervical pedicle diameter size differs between Asians and non-Asians. The authors studied the transverse pedicle diameter of the C2-C7 of the cervical spine in a Malaysian population using computerized tomography (CT) measurements. The transverse diameter of the pedicle is the determinant of the feasibility of this technique because the sagittal diameter of the pedicle has been wider than the transverse pedicle diameter. OBJECTIVES: To study the average transverse pedicle diameter of the cervical spine in a Malaysian population, and evaluate the feasibility and safety of pedicle screw fixation in these patients. SUMMARY OF BACKGROUND DATA: Cervical transpedicular screw fixation has been safe and is most probably going to be the gold standard for cervical spine fixation. However, its use in the Asian population should be considered cautiously because our cervical pedicle diameter may not be adequate to accommodate the standard pedicle screw size, which can be dangerous because there are vital structures located adjacent to the pedicles. METHODS: The measurements of the cervical pedicles were performed on CT images using its measurement tools. CT cutting was made at 2.5-mm intervals. The pedicle transverse diameters were defined as the most outer diameter of the pedicle, taken perpendicular to the axis of the pedicle and measured in millimeters up to 0.1 mm. RESULTS: The mean transverse diameters of the cervical pedicle of C2, C3, C4, C5, C6, and C7 in males were 5.4, 5.2, 5.1, 5.2, 5.5, and 6.5 mm, respectively, and ranged between 5.1 and 6.5 mm. In females, the mean transverse diameter of the cervical pedicle of C2, C3, C4, C5, C6, and C7 were 5.0, 4.6, 4.7, 4.9, 5.2, and 5.6 mm, respectively, and ranged between 4.6 and 5.6 mm. If the minimum transverse diameter required is 5.0 mm for 3.5-mm screw insertion, about 4.2% to 54.2% (male) of pedicles at different levels and 6.7% to 73.3% (females) of patients cannot have fixation with a 3.5-mm screw using this technique. CONCLUSION: Transpedicular screw fixation for the cervical spine must not be attempted in the Malaysian population before the exact pedicle diameters are known.Therefore, preoperative CT evaluation is a must before transpedicular fixation is performed, especially in female patients. Because the margin for mistake is very narrow, it is best avoided in upper cervical spines.