Ashu Seith Bhalla

Diffusion-weighted MRI in renal cell carcinoma: A surrogate marker for predicting nuclear grade and histological subtype:

Background Though previous investigators have attempted to evaluate its utility in characterization of focal renal lesions, diffusion-weighted MR imaging (DW MRI) in renal diseases is still an evolving field and its role in predicting the aggressiveness of renal cell carcinoma (RCC) is yet to be established. Purpose To assess whether apparent diffusion coefficient (ADC) values can be used to determine the nuclear grade and histological subtype of RCCs and to identify the tumor attributes contributing to variation in ADC values. Material and Methods The institutional ethics committee waived the requirement of informed consent for this retrospective study. The study cohort consisted of 33 patients who underwent MRI (with diffusion-weighted imaging at b values of 0 and 500 s/mm2) and were found to have 36 pathologically-proven RCCs. ADC values were determined for solid portions of RCC, cystic/hemorrhagic areas, and normal renal parenchyma. Histological subtype, nuclear grade, and cell count were determined for each lesion. ADC values were compared between different grades and subtypes and correlation with cell count was investigated. Receiver operating characteristic curves were drawn to establish cut-off ADC values. Results There were 23 low grade (grades I and II) and 13 high grade tumors (grades III and IV). There were 32 clear-cell and four non-clear-cell RCCs. A decreasing trend of ADC values was seen with increasing grade and mean ADC of high grade RCC was significantly lower than low grade (1.3145 vs 1.6982 × 10−3 mm2/s) (P = 0.005). Mean ADC for clear-cell RCC was significantly higher than non-clear-cell RCC (1.6245 vs. 1.0412 × 10−3 mm2/s) (P = 0.005). ADC values higher than 1.7960 × 10−3 mm2/s were seen only with low grade and values greater than 1.4904 × 10−3 mm2/s were seen only with clear-cell RCC. Conclusion ADC values provide a non-invasive means to predict the nuclear grade and histological subtype of RCC. Cellularity and morphology are other tumor attributes contributing to the variation in ADC values of RCCs.

Adjuvant therapy with flutamide for presurgical volume reduction in juvenile nasopharyngeal angiofibroma

Although 2 studies totaling 11 cases have indicated some benefit of anti‐androgen treatment with flutamide on juvenile nasopharyngeal angiofibroma (JNA), it is not part of contemporary practice.

Chest tuberculosis: Radiological review and imaging recommendations.

Chest tuberculosis (CTB) is a widespread problem, especially in our country where it is one of the leading causes of mortality. The article reviews the imaging findings in CTB on various modalities. We also attempt to categorize the findings into those definitive for active TB, indeterminate for disease activity, and those indicating healed TB. Though various radiological modalities are widely used in evaluation of such patients, no imaging guidelines exist for the use of these modalities in diagnosis and follow-up. Consequently, imaging is not optimally utilized and patients are often unnecessarily subjected to repeated CT examinations, which is undesirable. Based on the available literature and our experience, we propose certain recommendations delineating the role of imaging in the diagnosis and follow-up of such patients. The authors recognize that this is an evolving field and there may be future revisions depending on emergence of new evidence.

Evaluation of diagnostic utility of multidetector computed tomography and magnetic resonance imaging in blunt pancreatic trauma: a prospective study

Background Blunt pancreatic trauma is an uncommon injury with high morbidity and mortality. Retrospective analyses of computed tomography (CT) performance report CT to have variable sensitivity in diagnosing pancreatic injury. Both a prospective analysis of multidetector CT (MDCT) performance and diagnostic utility of magnetic resonance imaging (MRI) in acute blunt pancreatic injury remain unexplored. Purpose To prospectively evaluate the utility of MDCT with MRI correlation in patients with blunt pancreatic trauma using intraoperative findings as the gold standard for analysis. Material and Methods The contrast-enhanced CT (CECT) scans of patients admitted with blunt abdominal trauma were prospectively evaluated for CT signs of pancreatic injury. Patients detected to have pancreatic injury on CT were assigned a CT grade of injury according to American Association for Surgery of Trauma classification. MRI was performed in patients not undergoing immediate laparotomy and MRI grade independent of CT grade was assigned. Surgical grade was taken as gold standard and accuracy of CT and MRI for grading pancreatic injury and pancreatic ductal injury (PDI) was calculated. A quantitative and qualitative comparison of MRI was also done with CT to determine the performance of MRI in acute pancreatic injury. Results Thirty out of 1198 patients with blunt trauma abdomen were detected to have pancreatic injury on CT, which was surgically confirmed in 24 patients. Seventeen underwent MRI and surgical correlation was available in 14 patients. CT and MRI correctly identified the grade of pancreatic injury in 91.7% (22/24) and 92.86% (13/14) patients, respectively. Both CT and MRI correctly identified PDI in 18/19 and 11/12 patients, respectively, with good inter-modality agreement of 88.9% (kappa value of 0.78). MRI also qualitatively added to the information provided by CT and increased diagnostic confidence in 58.8% of patients. Conclusion MDCT performs well in grading pancreatic injury and evaluating pancreatic ductal injury. MRI is useful in evaluation of acute pancreatic trauma as it can increase diagnostic confidence and provide more qualitative information regarding the extent of injury.

In vivo characterization of urinary calculi on dual-energy CT: going a step ahead with sub-differentiation of calcium stones

Background The role of dual-energy computed tomography (DECT) in characterization of urinary calculi is evolving and literature regarding differentiation of calcium calculi is sparse and confounding. Purpose To evaluate the capability of DECT in assessing the urinary calculi composition in vivo, especially in differentiating various types of calcium calculi. Material and Methods One hundred and twenty patients underwent DECT for characterization of urinary calculi. Seventy patients with 114 calculi, including 93 calcium stones, were retrospectively analyzed. DE ratios and attenuation differences were compared using ANOVA and receiver-operating-characteristic (ROC) analysis was done to predict cut-off values, in particular for detecting calcium-oxalate-monohydrate (COM) stones. Results DE ratio ≤1.14 accurately detected uric acid calculi, ≥1.29 was definitive for calcium and intermediate values were characteristic of cystine stones. DE ratios were significantly different between group 1 (COM [n = 32]; mean 1.376 ± 0.041), group 2 ([calcium oxalate dihydrate (COD) + COM] [n = 51]; 1.416 ± 0.048), and group 3 ([carbonate apatite (CaP) + COD + COM] [n = 10]; 1.468 ± 0.038) (group 1 vs. 2, P = 0.001; 1 vs. 3, P = 0.000; 2 vs. 3, P = 0.004). More importantly, pure COM calculi (group 1) had significantly lower DE ratio compared with mixed calcium calculi (groups 2 and 3) (P = 0.000). Attenuation differences (between low and high kV images) could not distinguish between COM and mixed calculi. ROC analysis for detection of COM calculi yielded AUC of 0.770 with cut-off DE ratio 1.385 (sensitivity 65.6%, specificity 82%) and value <1.335 was seen only with COM calculi (100% specificity). Conclusion DECT can be employed for in vivo differentiation of various types of calculi and for detection of relatively lithotripsy-resistant COM calculi.

Bilateral adrenal lesions

Bilateral adrenal lesions include a spectrum of disorders: neoplastic disorders (metastases, lymphoma, bilateral phaeochromocytoma, adrenocortical carcinoma and myelolipoma); longstanding congenital adrenal hyperplasia and macronodular adrenal hyperplasia; infections such as tuberculosis, histoplasmosis and blastomycosis; adrenal haemorrhage; adrenals in hypoperfusion complex and paediatric masses. Bilateral distribution in addition to other imaging characteristics can help narrow differential diagnoses in case of adrenal masses. We present a pictorial review highlighting the adrenal lesions that can present bilaterally.

Fire during the use of Nd–Yag laser

Fire during the use of Nd-Yag laser is a very rare complication. A case report of laser fire during the use of Nd-Yag laser for congenital subglottic stenosis is reported. The probable causes for the fire, management and short review of literature are dealt with. This case report highlights the importance of following the safety protocol during laser surgery.

A Retrospective Analysis of 334 Cases of Hemoptysis Treated by Bronchial Artery Embolization

OBJECTIVES To analyze the safety and efficacy of bronchial artery embolization (BAE) in the management of hemoptysis. METHODS We conducted a retrospective study of 334 patients who had undergone BAE for hemoptysis from January 2007 to July 2013. Our study included 255 (76.3%) males and 79 (23.7%) females with an age range from five to 81 years old. All relevant arteries were evaluated but only those arteries that showed hypertrophy and significant blush were targeted. Polyvinyl alcohol (PVA) was used in all patients and gel foam was used in combination with PVA where there was significant shunting. RESULTS Mild hemoptysis was seen in 70 patients, moderate in 195 patients, and severe in 69 patients. On imaging, right side disease was seen in 101 patients, left side involvement in 59 patients, and bilateral involvement in 174 patients. Post-tubercular changes were the predominant pathology seen in 248 patients. Among 334 patients (386 procedures), 42 patients underwent the procedure twice and five patients underwent the procedure thrice. A total of 485 arteries were attempted of which 440 arteries were successfully embolized. Right intercosto-bronchial was the most common culprit artery present in 157 patients, followed by common bronchial (n=97), left bronchial (n=55), and right bronchial (n=45). We embolized a maximum of four arteries in one session. Immediate complications such as dissection and rupture occurred in only nine sessions (2.3%). Twenty-five procedures (6.5%) were repeated within two months, which were due to technical or clinical failure and 27 procedures (7%) were repeated after two months. CONCLUSIONS BAE is a safe and effective procedure with a negligible complication rate. Our approach of targeting hypertrophied arteries was effective.

Diffusion-weighted MRI in assessment of renal dysfunction

Background: Diffusion-weighted magnetic resonance imaging (DW-MRI) in renal diseases is an evolving field and its potential is yet to be fully realized. Purpose: To study the relationship between apparent diffusion coefficient (ADC) values of renal parenchyma and serum markers of renal function and stage of chronic kidney disease (CKD). Materials and Methods: A retrospective review was performed of all adult patients who underwent DW-MRI (at b-values of 0 and 500 s/mm2) for renal lesions from January 2009 to September 2010 and revealed 88 patients, of which 22 patients had renal dysfunction and 66 had normal renal function. Of these 22, 15 patients were known cases of CKD and were staged depending on disease severity. ADC values were determined for renal parenchyma and compared. Receiver operating characteristic (ROC) curves were drawn to establish cut-off ADC values. Pearsons correlation coefficient (R) was calculated between ADC and renal function parameters. Results: ADC values in patients with renal dysfunction were significantly lower than in patients with normal renal function (2.1133 ± 0.2851 vs. 2.3198 ± 0.1246 (×10-3 mm2/s)). ADC values lower than 2.0354 (×10-3 mm2/s) were seen only with renal dysfunction and higher than 2.4516 (×10-3 mm2 /s) were seen only with normal function. There was significant inverse correlation between ADC and serum creatinine (R = -0.530), blood urea (R= -0.502), and significant linear correlation (R = 0.784) with estimated glomerular filtration rate (eGFR). ADC values showed a statistically significant decreasing trend with increasing stage of CKD. Conclusion: ADC values may serve as an additional marker for the presence and degree of renal dysfunction.

Multidetector CT evaluation of central airways stenoses: Comparison of virtual bronchoscopy, minimal-intensity projection, and multiplanar reformatted images

Aims: To evaluate the diagnostic utility of virtual bronchoscopy, multiplanar reformatted images, and minimal-intensity projection in assessing airway stenoses. Settings and Design: It was a prospective study involving 150 patients with symptoms of major airway disease. Materials and Methods: Fifty-six patients were selected for analysis based on the detection of major airway lesions on fiber-optic bronchoscopy (FB) or routine axial images. Comparisons were made between axial images, virtual bronchoscopy (VB), minimal-intensity projection (minIP), and multiplanar reformatted (MPR) images using FB as the gold standard. Lesions were evaluated in terms of degree of airway narrowing, distance from carina, length of the narrowed segment and visualization of airway distal to the lesion. Results: MPR images had the highest degree of agreement with FB (Κ = 0.76) in the depiction of degree of narrowing. minIP had the least degree of agreement with FB (Κ = 0.51) in this regard. The distal visualization was best on MPR images (84.2%), followed by axial images (80.7%), whereas FB could visualize the lesions only in 45.4% of the cases. VB had the best agreement with FB in assessing the segment length (Κ = 0.62). Overall there were no statistically significant differences in the measurement of the distance from the carina in the axial, minIP, and MPR images. MPR images had the highest overall degree of confidence, namely, 70.17% (n = 40). Conclusion: Three-dimensional reconstruction techniques were found to improve lesion evaluation compared with axial images alone. The technique of MPR images was the most useful for lesion evaluation and provided additional information useful for surgical and airway interventions in tracheobronchial stenosis. minIP was useful in the overall depiction of airway anatomy.