Correspondence Address:
Sanjay Sharma
Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi
India

Full Text

In my two decades of association with urology, I have closely witnessed the growing contribution of imaging in this specialty. In return, I acknowledge with gratitude the gaining of knowledge, respect, and wisdom through this association. In the past, there used to be numerous questions for which we had no easy answers. Fortunately, imaging science has benefited from recent technological advances and techniques, allowing us to better understand and correlate imaging with pathology. These advances have enabled uroradiology to evolve as a credible subspeciality. Today, we feel more comfortable in answering many of those challenging questions. However, the demands have increased further. Surgical advances have resulted in our surgical colleagues demanding greater information from radiologists so that they may manage their patients in a better manner. These events remind me of an all-time favorite proverb, "good, better, best; never let them rest...''

State-of-the-art ultrasound technology now allows the acquisition of higher resolution images. The recent introduction of elastography and ultrasound contrast agents have further enhanced our capability in many clinical situations, especially in oncology. These include differentiation of solid renal masses from cysts, detection of solid nodules within echogenic/hemorrhagic cysts, and identification of suspicious targets during prostate biopsies. These techniques are still evolving and their full potential remains to be exploited. Dual-energy computed tomography (DECT) allows us to acquire exquisite volume-rendered angiographic images and noninvasively characterize renal calculi more reliably. It has allowed us to modify the traditional CT urography protocols by extracting virtual, noncontrast images from the contrast scans. When combined with split bolus techniques, single DECT acquisition can provide arterial, nephrographic, and pyelographic phases in single series, thereby drastically reducing the radiation dose. [1]

Over these years, magnetic resonance imaging (MRI) has leapfrogged from being a standard anatomical imaging modality to one providing vital functional information about the cellularity of solid tissues (diffusion weighted imaging), perfusion parameters in neoplasms (dynamic contrast imaging), and relative concentration of intracellular metabolites (spectroscopy). In this respect, multiparametric MRI has truly proved to be a game-changer in uro-oncology. It has further improved the characterization of renal cysts over traditional CT-based Bosniak grading and has increased our confidence in evaluating small renal masses. Owing to its high negative predictive value of around 90% [2] in detecting significant prostate cancer, multiparametric MRI has refined the standard prostate-specific antigen (PSA)-based treatment algorithms. A prebiopsy MRI saves unnecessary prostate biopsies, supports "in-bore" targeting of cancer foci for biopsy and ablative therapy, and provides an effective active surveillance strategy. However, these imaging advances have outpaced their implementation in clinical practice. A prebiopsy prostate MRI is not the standard recommendation in the practice guidelines of leading international urological societies.

The review articles in this issue of the journal look at both the basic percutaneous procedures and some cutting-edge urologic procedures. These include MRI-based techniques of guiding prostate biopsies, percutaneous ablation of renal and early prostate cancers, prostate artery embolization in the management of benign prostatic enlargement, and of course the use of endovascular embolization in the management of hematuria of diverse etiologies. The success of these attractive alternative procedures needs both experience and dexterity. Globally, these are being carried out by radiologists to whom referrals must be considered by surgeons wherever appropriate. While this clearly indicates the growing capabilities of radiologists, I only hope that the turf battles remain a nonissue and an endeavor for a favorable clinical outcome reigns supreme.

This issue presents a comprehensive overview of some of these topics and we hope to sensitize readers about the state-of-the-art urologic imaging. I have no hesitation to say that uroradiology is currently at its prime, well-poised to take another big leap in the future. Unfortunately, new technology is expensive, restricted to select few centers, and has limited training opportunities. It is hoped that the choice of a radiological investigation would not be driven by technology alone but guided by its efficacy, ethics, economics, and above all, experience. I am grateful for being given an opportunity to guest-edit this symposium. I owe this largely to my friends from within and outside the country for their valuable and timely contributions. I earnestly hope that this issue will be well-received.

References