Narouze SN, ed. Atlas of Ultrasound-Guided Procedures in Interventional Pain Management. Springer 2011, 372 pages, 465 illustration, $189.00.
In 1941, Dr. Karl Theodore Dussik of Austria introduced the idea of using ultrasound waves as a diagnostic tool. Over the next few decades he, along with others like Professor Ian Donald of Scotland, developed the practical technology and applications of ultrasound in the field of medicine. Since then, ultrasound (US) has become progressively more useful across a wide range of medical specialties, for both diagnostic and therapeutic procedures. US is quickly becoming the imaging modality of choice to guide practitioners in pain management and musculoskeletal interventions. Although fluoroscopy has long been a mainstay in image-guidance for such procedures, US provides an attractive alternative given its superior soft tissue resolution, allowance of real-time needle guidance, absence of iodinated contrast and lack of ionizing radiation.
The Atlas of Ultrasound-Guided Procedures in Interventional Pain Management by Narouze et al. is a comprehensive review of the principles of US-guidance as an aid in current pain management practices. It is divided into six parts and 30 chapters arranged by system and discipline. Leading experts in each discipline have contributed to this body of work, providing an extensive literature review encompassing each chapter. This text is meant to serve as a user-friendly manual, covering the anatomy, treatment rationale, and technical aspects of US-guided interventional pain management procedures.
PART I: Imaging in Interventional Pain Management and Basics of Ultrasonography
The introductory section of the text reviews the imaging modalities currently utilized in interventional pain management. These include fluoroscopy, computed tomography (CT) and ultrasound. The accuracy, precision, safety and diagnostic benefits gained by the use of image-guided modalities make them more attractive than using surface landmarks. A brief risk to benefit analysis highlights the strengths and weaknesses of each modality in various scenarios.
The section includes a discussion of the utility of ultrasound in intra-articular injections, trigger point and muscular injections, zygapophyseal and medial branch blocks, epidural blocks, sympathetic blocks, and the combination use of ultrasound and CT/fluoroscopy.
A concise yet satisfactory review of the basics of US imaging is provided as background for the sections to follow. The principles of US pulse generation, wavelength, frequency and US-tissue interaction are outlined and reinforced with helpful diagrams, tables and images. The essential knobology for US-guided regional anesthesia and interventional pain management provide a user-friendly guide to optimize the image obtained from US machine operation. The last chapter of the section guides the reader through the process of improving needle visibility for US-aided procedures. Inadequate needle visualization during a procedure may lead to inadvertent vascular, neural or visceral injury. Vascular puncture injuries have been decreased by 30% with the use of real-time visualization via US. This chapter is quite thorough in exploring the multitude of factors that impact needle placement. An emphasis is placed on the importance of proper training with adequate mentorship and the use of high-fidelity simulation in the mastery of the described techniques. The factors discussed include but are not limited to needle type (echogenic), insertion site and angle, the US device, needle-probe alignment, “in-plane” and “out-of-plane” needle approaches as well as ergonomics. Side-by-side clinical images with corresponding US images provide a realistic illustration of techniques described. Overall, Part I of the text provides a high-quality introduction to the subject matter and a step-by-step guide to the general principles of US-guided procedures which sets the stage for a more detailed discussion and description of this modality on an anatomical basis.
PART II: Spine Sonoanatomy and Ultrasound-Guided Spine Injections
The second section focuses on sonographic exploration and interventions involving the spine. A review of the cervical, thoracic, lumbar and sacral spine is provided and supported by labeled gross anatomical photographs. Although an extremely useful method of identifying and protecting delicate structures from damage during procedures, US continues to have important limitations which are appropriately addressed. Perhaps most notable is the distinction between the superficial and deep anatomy. Generally speaking, more superficial structures such as bony contours, synovial joint capsules or entrances are more consistently visualized with greater image quality as compared to deeper structures. Working with deep articular cavities of zygapophyseal and sacroiliac joints, vertebral canal, epidural space, intervertebral foramina, paravertebral space and nerve roots as well as sacral foramina and vertebral arteries tends to be more challenging. Detailed sonoanatomy of the entire spine divided into the four anatomical regions is presented in a clear and comprehensive manner. Emphasis is placed on the distinction between the superficial and deep anatomy as figures display anatomical models, cadaveric dissections and US imaging to demonstrate various correlations.
US-guided blockade of the third occipital and cervical medial branch nerves are discussed starting with the indications for both. The authors cite the relevant literature and as well as their own clinical experience in the treatment rationale outlining the advantages and limitations of US methods. The primary advantage of US over CT or fluoroscopy is the ability to visualize the cervical medial branch for local anesthetic injection. However, the quality of visualization is dependent on patient body habitus and thus presents a limitation. Step-by-step explanations of the related techniques are included with clinical photographs that demonstrate US probe placement and proper needle location. The section goes on to cover cervical zygapophyseal (facet) intra-articular injections describing both lateral and medial approaches. Additionally, a thorough description of US-guided thoracic paravertebral, lumbar zygapophyseal nerve and neuraxial blocks as well as lumbar nerve, caudal, ganglion impar and sacroiliac joint injections is provided. Many of the sources cited underscore the benefit US-guidance in interventional spinal procedures. The ability to identify vital neurological and vascular anatomy allows practitioners to effectively execute diagnostic and therapeutic procedures while protecting these structures.
PART III: Ultrasound-Guided Abdominal and Pelvic Blocks
Transversus abdominis plane block aided by US is a proven management option for chronic pancreatitis, post-operative pain, and various other causes of abdominal pain. The classic or “double-pop” approach originally described by Rafi and McDonell is reviewed and followed by a description of the US-guided technique and its benefits. Celiac plexus blockade and neurolysis has been widely accepted in the management of malignant and nonmalignant pain conditions in the pancreas, liver, gall bladder, mesentery, omentum and portions of the gastrointestinal tract from the lower esophagus to the transverse colon. The advantages and limitations of the use of US-guidance in common approaches are evaluated including related diagrams and sonographic images.
Lastly, management of chronic pelvic pain is addressed. This phenomenon is complex as potential etiologies may stem from the viscera, neuromuscular system or the gynecological system. Operative and traumatic damage to ilioinguinal, iliohypogastric and genitofemoral nerves are relatively common causes of pelvic pain. Additionally, piriformis syndrome and pudendal neuralgia are outlined and sonoanatomy with US-guided blockade techniques are illustrated. Moreover, an extensive literature review references data that validates the use of US for the identification of the target structures associated with chronic pelvic pain.
PART IV: Ultrasound-Guided Peripheral Nerve Blocks and Continuous Catheters
Peripheral nerve blocks and continuous catheters are useful methods of pain management in the extremities. Like many other procedures mentioned US-guidance has enhanced the delivery of these treatment options. The chapter on upper extremity nerve blocks systematically outlines the anatomy, indications and techniques for interscalene, supraclavicular, infraclavicular, axillary and distal peripheral nerve blocks. The figures display a trio of cross-sectional diagrams, clinical photographs and sonographic images which provide an excellent illustration of the procedures described. The description US-guided nerve blockade in the lower extremity follows in a similar fashion; however, there is additional emphasis placed on preparation and positioning. Femoral nerve, sciatic nerve (proximal and within the popliteal fossa), lumbar plexus, obturator nerve, lateral femoral cutaneous nerve, saphenous nerve and ankle blockade techniques are included. Next, cervical sympathetic block via the classical approach is briefly described using US-guidance.
In addition to transient blockade techniques, continuous catheters which extend the duration of anesthesia and analgesia have also benefitted from the use of US-guidance. The chapter dedicated to these techniques distinguishes between in-plane vs. out-of-plane needle trajectory as well as long vs. short axis transducer orientation relative to the nerve. General perineural catheter insertion preparation is reviewed and followed by the most common associated procedures including interscalene, infraclavicular, femoral, subgluteal sciatic, popliteal sciatic and transversus abdominis plane continuous peripheral nerve blocks. The above methods are well established in the management of various chronic neuromuscular pain phenomena as well as peri-operative pain control. The advent of US-guidance has a clear role in improving the accuracy, efficacy and safety of such procedures.
PART V: Musculoskeletal (MSK) Ultrasound
Musculoskeletal pain is an extremely common etiology requiring pain management. In general, office-based procedures are able to access the involved structure(s) without difficulty. Nevertheless, in cases of smaller joint spaces or joint pathology intra-articular injection procedures can become challenging. US-guidance can in many instances reduce these challenges and improve outcomes. Additionally, clinicians can perform dynamic assessments of the involved joint under real-time sonographic imaging.
The MSK section includes a discussion on US-guided shoulder and bursa injections outlining the anatomy and techniques targeting the subacromial/subdeltoid bursa, biceps tendon sheath, acromio-clavicular joint and glenohumeral joint. The chapter on hand, wrist and elbow injections review the anatomy, relevant literature and describe US-guided techniques which include carpel tunnel, trigger finger, wrist and elbow injections as well as tendon dysfunction techniques for de Quervain’s tenosynovitis, intersection syndrome, lateral epicondylitis and tendon impingement.
With the growing aging and increasingly obese population in the United States and other developed nations the incidence of hip and knee problems is expected to increase in the years to come. Intra-articular hip injection is a proven management option; however, the deep joint location with adjacent neurovascular structures poses a valid concern in the use of blind landmark-based techniques. Furthermore, a large body habitus, common in this patient population, introduces an additional limitation to this procedure. US-guidance is useful in anatomical visualization of important structures; however, body habitus remains a as a limitation which can diminish its utility. Although intra-articular knee injections are commonly used and widely accepted as a blind procedure the text cites data that identify suboptimal accuracy. Additionally, the authors reference reports of substantial increases in accuracy with the use of US-guidance; however, the data on this topic is limited.
PART VI: Advanced and New Applications of Ultrasound in Pain Management
There are several new and promising applications of US in the field of pain management. In the realm of nerve stimulation, the text references recent work that uses US for placement of percutaneous trials in order to avoid unnecessary incisions in non-responders. An outline of procedures addressing radial nerve stimulation, ulnar, median, sciatic and posterior tibial nerves is included. Operative photographs along with diagrams and sonographic imaging help illustrate the described techniques. US-guided greater occipital nerve stimulation for management of intractable headache disorders and groin neurostimulation for intractable groin and pelvic pain are both discussed briefly. Lastly, the use of US in atlanto-axial and atlanto-occipital joint injections as well as discography and intradiskal procedures completes this innovative section. In general, the current evidence supporting the above topics remains limited, and this must be considered prior to utilizing US in any of the procedures described. Further studies are needed at this time to completely evaluate the efficacy of these potentially useful methods.
The text is very well organized and straightforward. The information is presented in an easy-to-understand, easy-to-use manner. The brief table of contents for each chapter facilitates efficient reference and review. References following each chapter allow for further research on a given topic. The content is comprehensive yet concise with reviews of current principles and anatomy to guide the reader along the way. The theme of side-by-side figures includes gross anatomy, diagrams, clinical photographs and sonographic images is extremely helpful.
There are several areas of improvement that should be mentioned. The text provides a thorough explanation of the rationale for and benefits of US-guided pain management procedures. However, the limitations and pitfalls are mentioned in brief. Perhaps a more complete discussion of these topics for each section is appropriate, as such challenges may have a potential impact in patient care. Additionally, a multimedia component would provide an even more realistic depiction of the information the authors have eloquently illustrated.
While US-guidance for interventional pain management has and continues to show a benefit, the text appropriately stresses the importance of proper training and mentorship. We must further underscore this notion. Of all the imaging modalities currently used, US is undoubtedly the most operator-dependent. Thus, the quality of the imaging and, therefore, the accuracy, safety and efficacy of associated procedures highly dependent of the practitioner. Accordingly, in addition to utilizing this text, it is imperative that clinicians seek specialty training via fellowship, formal mentorship or continuing medical education, in order to master the principles and skills presented by Narouze and colleagues. This will ensure that patients receive the intended benefits of these practices.
*This blog post was originally published at AJNR Blog*