Study on Closure of Skull Base Defect Post-Endoscopic Endonasal Transsphenoid Pituitary Surgery: A Novel Flap Design

Objective  This study was aimed to compare the closure of skull base defect in endoscopic endonasal transsphenoid surgery of pituitary tumors, using bipedicled nasal septal flap versus fascial closure. The study hypothesis being that bipedicled nasal septal flap is better, compared with fascial closure of skull base defect post-endoscopic endonasal transsphenoid surgery of pituitary tumors. Methods  All the eligible patients were randomly divided into two groups and then randomly allocated to the surgeons. In one group, fat and fascia lata was used for closure of the skull base defect and nasal septal flap was not harvested whereas in the other, nasal septal flap was used for closure. Results  There was a statistically significant difference in postoperative cerebrospinal fluid leak between the two groups. Patients who had undergone flap repair had lower incidence of postoperative cerebrospinal fluid (CSF) leak. Duration of postoperative hospital stay was also less among the group who underwent flap repair (statistically significant). Conclusion  Bipedicled nasal septal flap serves an excellent cover for the skull base defect following endoscopic endonasal transsphenoidal pituitary surgery. It can prevent postoperative CSF leak even in cases where tissue glue is not used.

Abdominal cocoon: preoperative diagnosis on CT

A 23-year-old man presented to the emergency department with a history of recurrent episodes of subacute intestinal obstruction. Palpation revealed a firm, non-tender, mobile, non-pulsatile mass of size 8-10 cm with indistinct margins and smooth surface in the hypogastrium. Contrast-enhanced CT scan of the abdomen showed clumping of the small bowel loops within a well-defined membrane-like structure without dilatation or thickening of bowel loops. The patient underwent a laparotomy with incision of the membrane and separation of all the small bowel loops inside the cocoon. Abdominal cocoon is the idiopathic variety of sclerosing encapsulating peritonitis and is an unusual cause of acute or subacute intestinal obstruction. Clinical diagnosis is difficult because of non-specific symptoms. CT has facilitated accurate preoperative diagnosis, long before the patient presents with full-fledged symptoms of acute intestinal obstruction. CT scan plays a significant role in excluding the secondary causes and helps in patient management.

An unusual presentation of gastric fistula following peptic perforation repair: A case report

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Late onset Gastrocutaneous fistulas are rare following the peptic perforation repair.

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A non-healing burst abdominal wound should be thoroughly investigated. It can be because of an underlying fistula.

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CT fistulogram is the investigation of choice to confirm the diagnosis.

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Operative intervention is difficult but the only method of cure in most of the circumstances.

Introduction

Peptic perforation repair is a common stomach surgery. This surgery has not been associated with delayed onset gastrocutaneous fistula formation. However such a complication has been reported following a variety of other stomach surgeries. We are reporting this case as it is a rare complication. Also its diagnosis and management is challenging.

Case summary

We are presenting a case of peptic perforation repair where burst abdomen happened in the immediate post-operative period. The patient was put on conservative management. He responded well to it but his abdominal wound was not healing. After a wait of four months the wound was covered with a skin graft. The graft uptake was satisfactory but a discharging ulcer appeared on it. This condition persisted for one month. Finally a computed tomography Fistulogram (CT Fistulogram) was performed. It revealed an underlying complex gastric fistula. A repeat surgery was performed.

Conclusion

A gastrocutaneous fistula diagnosed at sixth month following the peptic perforation repair and causing minimal discomfort to the patient is a rare presentation. The abdominal wound following the surgery was possibly not healing because of the underlying fistula.

Utility of multiparametric 3-T MRI for glioma characterization

INTRODUCTION

Accurate grading of cerebral glioma using conventional structural imaging techniques remains challenging due to the relatively poor sensitivity and specificity of these methods. The purpose of this study was to evaluate the relative sensitivity and specificity of structural magnetic resonance imaging and MR measurements of perfusion, diffusion, and whole-brain spectroscopic parameters for glioma grading.

METHODS

Fifty-six patients with radiologically suspected untreated glioma were studied with T1- and T2-weighted MR imaging, dynamic contrast-enhanced MR imaging, diffusion tensor imaging, and volumetric whole-brain MR spectroscopic imaging. Receiver-operating characteristic analysis was performed using the relative cerebral blood volume (rCBV), apparent diffusion coefficient, fractional anisotropy, and multiple spectroscopic parameters to determine optimum thresholds for tumor grading and to obtain the sensitivity, specificity, and positive and negative predictive values for identifying high-grade gliomas. Logistic regression was performed to analyze all the parameters together.

RESULTS

The rCBV individually classified glioma as low and high grade with a sensitivity and specificity of 100 and 88 %, respectively, based on a threshold value of 3.34. On combining all parameters under consideration, the classification was achieved with 2 % error and sensitivity and specificity of 100 and 96 %, respectively.

CONCLUSION

Individually, CBV measurement provides the greatest diagnostic performance for predicting glioma grade; however, the most accurate classification can be achieved by combining all of the imaging parameters.

Subcompartmentalization of extracellular extravascular space (EES) into permeability and leaky space with local arterial input function (AIF) results in improved discrimination between high- and low-grade glioma using dynamic contrast-enhanced (DCE) MRI

PURPOSE

To modify the generalized tracer kinetic model (GTKM) by introducing an additional tissue uptake leakage compartment in extracellular extravascular space (LTKM). In addition, an implicit determination of voxel-wise local arterial input function (AIF) Cp (t) was performed to see whether these changes help in better discrimination between low- and high-grade glioma using dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI).

MATERIALS AND METHODS

The modified model (LTKM) was explored and fitted to the concentration-time curve C(t) of each voxel, in which the local AIF Cp (t) could be estimated by a time invariant convolution approximation based on a separately measured global AIF Ca (t). A comparative study of tracer kinetic analysis was performed on 184 glioma patients using DCE-MRI data on 1.5T and 3T MRI systems.

RESULTS

The LTKM analysis provided more accurate pharmacokinetic parameters as evidenced by their relative constancy with respect to the length of concentration-time curve used. In addition, LTKM with local AIF resulted in improved discrimination between low-grade and high-grade gliomas.

CONCLUSION

LTKM with local AIF provides more accurate estimation of physiological parameters and improves discrimination between low-grade and high-grade gliomas as compared with GTKM.