Bhawan K. Paunipagar

Use of rapid prototyping and three-dimensional reconstruction modeling in the management of complex fractures

BACKGROUND The production of a copy of the fracture or a deformity in a bone with a complex geometry can be one of the important applications of the integration between two modern computer-based technologies, reverse engineering (RE) and rapid prototyping (RP). METHODS This article reviews recent development in this field and present a case series about the use of medical CT/MRI scanning, three-dimensional reconstruction, anatomical modeling, computer-aided design, RP and computer-aided implantation in treating a complex fracture of acetabulums, calcaneum, and medial condyle of femur (Hoffas fracture). CONCLUSION The use of RP technology helped us to understand the fracture configuration and to achieve near anatomical reduction. With this we believe, this technology will reduce the surgical time as was observed in our cases. This consequently, will lower the requirement of an anesthetic dosage and decrease the intraoperative blood loss.In summary, the merging of computational analysis, modeling, designing, and fabrication will serve as important means to treat conditions and fractures around joints, spine, acetabulum, and craniofacial region. LEVEL OF EVIDENCE Level 4, case series.

Imaging of the anterior cruciate ligament

The anterior cruciate ligament (ACL) is an important structure in maintaining the normal biomechanics of the knee and is the most commonly injured knee ligament. However, the oblique course of the ACL within the intercondylar fossa limits the visualization and assessment of the pathology of the ligament. This pictorial essay provides a comprehensive and illustrative review of the anatomy and biomechanics as well as updated information on different modalities of radiological investigation of ACL, particularly magnetic resonance imaging.

Pulmonary metastases in children with osteosarcoma: characteristics and impact on patient survival

BackgroundApproximately 15–20% of patients with osteosarcoma present with detectable metastatic disease and the majority of whom (85%) have pulmonary lesions as the sole site of metastasis. Previous studies have shown that the overall survival rate among patients with localized osteosarcoma without metastatic disease is approximately 60–70% whereas survival rate reduces to 10–30% in patients with metastatic disease.ObjectiveTo determine the incidence and characteristic features of pulmonary metastases in a group of osteosarcoma patients and correlate the findings with the prognostic outcome/survival.Materials and methodsSeventy-seven cases of histologically confirmed osteosarcoma were reviewed (47 male, 30 female, mean age 10.9). The site and size of the primary tumour and degrees of chemonecrosis were recorded. Lung metastases were analyzed according to their size, number, distribution and interval from diagnosis. The Kaplan-Meier method was used to analyze the survival probability curve. Significant differences (P < 0.05) were evaluated with the log-rank test for univariate analyses.ResultsSeventeen patients had synchronous and 11 had metachronous lung metastases. Sixteen (57%) underwent pulmonary metastasectomy. Nine of sixteen (56%) patients with metastasectomy and 10/12 (83%) patients without metastasectomy died. Poor chemonecrosis was associated with a worse outcome. Number, distribution and timing of lung metastases, but not the size of lung metastases, were of prognostic value for survival.ConclusionRadiological detection of lung metastases is clinically important as it indicates a worse prognosis.

Pictorial review of mucopolysaccharidosis with emphasis on MRI features of brain and spine

Mucopolysaccharidosis (MPS) is an inherited metabolic disorder of childhood, characterised by progressive multisystem involvement predominantly affecting the skeletal system leading to skeletal dysplasia. Mental retardation, neuropathy and cardiomyopathy may occur in the most severely affected patients, leading to progressive disability and death in their early third to fourth decades. The purpose of this paper is to illustrate the typical imaging features of different types of MPS, in particular the MR features of the brain and spine in MPS, which are expected to be encountered by radiologists more frequently in their clinical practice as a result of prolonged life expectancy for those with MPS with recent advances in therapeutic interventions. The treatment options and outcomes for MPS patients are also briefly discussed.

Atypical location of germinoma in basal ganglia in adolescents: radiological features and treatment outcomes

The objective of this work is to describe the imaging findings, clinical profile and treatment response in four Chinese adolescent patients presenting with ectopic germinoma arising from basal ganglia. The clinical presentation, treatment regimens and the imaging findings at presentation and after treatment were described upon retrospective review of four Chinese adolescent patients. CT of the brain showed mixed solid cystic mass lesions in three patients. In one patient, only ill-defined hyperdensity was noted in the affected basal ganglia. Correlative MRI brain studies showed similar findings of large solid cystic masses in three patients, whereas the fourth patient showed small hyperintensities on T2 weighted and fluid-attenuated inversion-recovery sequences. All lesions were confirmed to be germinomas on biopsy. Chemotherapy followed by radiotherapy was given to three patients. There was a dramatic response, with complete resolution of tumour bulk in two patients and >80% reduction in tumour bulk in one patient. Debulking surgery was performed in one subject who had received cranial radiotherapy; the last follow-up MRI showed no evidence of residual disease.

Paediatric intra-axial posterior fossa tumours: pictorial review

Paediatric brain tumours commonly arise in the posterior cranial fossa. Early diagnosis is often challenging due to initial non-specific clinical symptoms, especially in very young children. The typical MR features of tumours in this region including medulloblastoma, ependymoma, juvenile pilocytic subtype of cerebellar astrocytoma, brain stem glioma and atypical teratoid–rhabdoid tumour are illustrated. Diffusion-weighted imaging and apparent diffusion coefficient values combined with signal characteristics on conventional MR sequences can usually differentiate low-grade from high-grade tumours. Prompt diagnosis is crucial as total surgical resection, which is only possible in localised disease, improves prognosis. A practical MR flow chart is introduced for differentiating different types of posterior cranial fossa tumours, which might be useful in clinical practice.

Radiographic study of the hip joint to determine anthropometric parameters for Indian population

Hip replacement surgeries are on the rise in India. However, for these surgeries, most of the implants used are imported and manufactured entirely to suit the geometrical considerations of the western population. Studies in the past have shown that there are anatomical variations in the hip joint for different ethnic backgrounds and geographical locations. There is paucity of anthropometric hip joint data related to Indian population and anthropometric variations in skeletal geometry between Asian and Western counterparts have not yet been thoroughly reviewed and considered for implant manufacturing. The purpose of this anthropometric study is to determine any anatomical variations in the normal hip joint among the Indian population and to statistically compare the mean values with the existing data on western population. 422 Hip radiographs of 211 individuals (141 males and 70 females) with normal and healthy hip joints were evaluated to obtain the horizontal offset, vertical offset and neck shaft angle. For males, mean neck shaft angle was 127.68° (SD = 3.94), horizontal offset was 34.60mm (SD=6.55) and vertical offset was 39.17 mm (SD = 5.86). For females, mean neck shaft angle was 125.92° (SD = 4.75), horizontal offset was 32.96 mm (SD = 7.04) and vertical offset was 36.38 mm (SD = 6.28). When these parameters were compared to the data available from western world, there were significant anatomical variations and it was evident that there is a need to evaluate existing implants in relation to this data and possibly design the implants suited and relevant to Indian population.

Intravascular papillary endothelial hyperplasia: report of two cases

Intravascular papillary endothelial hyperplasia is a rare benign vascular proliferative process as a result of papillary proliferation of the endothelial cells within the vascular lumen. We report two cases of intravascular papillary endothelial hyperplasia affecting the extremities. The characteristic sonological and MR imaging features are discussed, with updated review of literature. Imaging features are helpful in achieving a definitive diagnosis of the intravascular papillary endothelial hyperplasia.

Mesenteric vasculitis with genitourinary tract involvement in systemic lupus erythematosus

A middle-aged man with systemic lupus erythematosus (SLE) presented with acute onset of abdominal pain associated with diarrhoea and vomiting. The patient was haemodynamically stable and the hydration was maintained. The patient also had intermittent urgency and a sense of incomplete urinary bladder emptying. Emergency multidetector CT scans of the abdomen and pelvis revealed moderate to severe wall oedema and mucosal swelling of the small bowel (figure 1) and entire length of the large colon (figure 2). There was moderate to severe stranding and increased vascularity within the mesentery and the mesocolon (figures 1 and 2). The major abdominal vessels, including the mesenteric arteries and veins, however, were patent. Figure 1 Contrast-enhanced axial CT scan of the abdomen showing multiple fluid-filled small bowel loops with thickened walls. Note the target appearance (alternating white and black layers) (white arrows), ascites (black arrowhead) and bilateral dilated ureters (white arrowheads). Figure 2 Contrast-enhanced axial CT scan of the …

Testicular Hamartomas and Epididymal Tumor in a Cowden Disease: A Case Report

Testicular hamartomas (TH) is a benign condition. An association of TH with Cowden disease (CD) is known. Ultrasound features of hamartomas are often diagnostic. We present a case of Cowden disease with TH and an epididymal tumor. Imaging features of TH and its differentials has been discussed. Although, association of Cowden disease with many malignancies have been documented, epididymal tumor has not been described. To our knowledge, this paper is the first to describe epididymal tumor in association with Cowden disease.