Ultrasound-guided interventional procedures for patients with chronic pelvic pain - a description of techniques and review of literature.
ABSTRACT Chronic pelvic pain can present in various pain syndromes. In particular, interventional procedure plays an important diagnostic and therapeutic role in 3 types of pelvic pain syndromes: pudendal neuralgia, piriformis syndrome, and "border nerve" syndrome (ilioinguinal, iliohypogastric, and genitofemoral nerve neuropathy). The objective of this review is to discuss the ultrasound-guided approach of the interventional procedures commonly used for these 3 specific chronic pelvic pain syndromes. Piriformis syndrome is an uncommon cause of buttock and leg pain. Some treatment options include the injection of the piriformis muscle with local anesthetic and steroids or the injection of botulinum toxin. Various techniques for piriformis muscle injection have been described. CT scan and EMG-guidance are not widely available to interventional physicians, while fluoroscopy exposes the performers to radiation risk. Ultrasound allows direct visualization and real-time injection of the piriformis muscle. Chronic neuropathic pain arising from the lesion or dysfunction of the ilioinguinal nerve, iliohypograstric nerve, and genitofemoral nerve can be diagnosed and treated by injection to the invloved nerves. However, the existing techniques are confusing and contradictory. Ultrasonography allows visualization of the nerves or the structures important in the identification of the nerves and provides the opportunities for real-time injections. Pudendal neuralgia commonly presents as chronic debilitating pain in the penis, scrotum, labia, perineum, or anorectal region. A pudendal nerve block is crucial for the diagnosis and treatment of pudendal neuralgia. The pudendal nerve is located between the sacrospinous and sacrotuberous ligaments at the level of ischial spine. Ultrasonography, but not the conventional fluoroscopy, allows visualization of the nerve and the surrounding landmark structures. Ultrasound-guided techniques offer many advantages over the conventional techniques. The ultrasound machine is portable and is more readily available to the pain specialist. It prevents patients and healthcare professionals from the exposure to radiation during the procedure. Because it allows the visualization of a wide variety of tissues, it potentially improves the accuracy of the needle placement, as exemplified by various interventional procedures in the pelvic regions aforementioned.
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ABSTRACT: BACKGROUND: Cryotechnology is a modality of renewed interest in pain management. It is safe and effective when used to treat neuropathies of sensory and mixed nerves. Cryoablation, in general, is devoid of the risk of neuroma formation and can provide several weeks to months of adequate pain relief. Traditionally, cryoablation was applied blindly to the target area. The use of ultrasound guidance may improve the efficacy and reduce morbidity. We report a case of a successful cryoablation of the femoral component of the genitofemoral nerve using ultrasound guidance in a patient with chronic inguinal pain. A 47 year-old male (ASA Classification II for obesity, HLD, and OSA, 125kg, 69 in) presented to the Walter Reed Pain Clinic with the complaint of 4/10 VAS left sided groin pain of 3 month duration. The patient was diagnosed with a neuropathy of the femoral component of the left genitofemoral nerve. He received a diagnostic block with local anesthetic and reported immediate pain relief that lasted one week. The patient was counseled on the risks and benefits of cryoablation. The skin was anesthetized with 1% lidocaine and a 14 gauge angiocatheter needle was introduced using an in-plane technique to the target area. A Westco Cryoablation machine (San Diego, California) with a 14 gauge Lloyd Neurostat cryoprobe was then passed via the angiocatheter. The area was treated for two 3-minute intervals while the cryo probe was visualized under ultrasound. Ultrasound is increasingly utilized for both acute and chronic pain procedures. Ultrasound offered several advantages in this case. It allowed a smaller gauge introducer and cryoablation probe to be used since there was better visualization of the target area. Ultrasound helped identify important vascular structures, allowing safe introduction of the introducer and cryoablation probe. The patient remains pain free at 2-month follow-up.Pain physician 12(6):997-1000. · 10.72 Impact Factor
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ABSTRACT: Objectives: Occipital nerve stimulation (ONS) is a peripheral nerve stimulation (PNS) technique that has been used with success in the management of intractable chronic daily headaches (CDHs) and occipital neuralgia (ON). The technique involves the placement of a stimulating surgical or percutaneous electrode over the occipital nerves within the subcutaneous tissues at the skull base. Until recently, procedures involving the occipital nerves were based on identifying bony or arterial landmarks with direct palpation or fluoroscopy. Although universally accepted as an imaging technique, fluoroscopy does not provide real-time imaging of the occipital nerves or vessels. Furthermore, therapeutic efficacy of ONS is directly related to the ability of the stimulating electrode to produce peripheral nerve dermatomal paresthesia, emphasizing the need for precision placement. Materials and Methods: A total of six patients, diagnosed with refractory CDH and ON, after failing extensive medical management, were diagnosed as potential candidates for ONS. Subsequently, all underwent successful percutaneous trials of bilateral octopolar (Advanced Neuromodulation Systems, Plano, TX, USA) ONS under ultrasound guidance, followed by permanent surgical implantation. Results: In this case series, ultrasound provided accurate, real-time placement of introducer needles and stimulating electrodes by allowing visualization of tissue planes (epidermis, dermis, subcutaneous fat, and trapezious muscle), as well as vessels and nervous structures. Conclusions: Ultrasound imaging has been used increasingly for peripheral nerve blockade in surgical anesthesia and in chronic pain management as it allows real-time localization of both nervous and vascular structures (color flow Doppler) and, thus, a method for increasing blockade precision and safety. As an adjunct to ONS, the position of the introducer needles and electrodes can be visualized in relation to the occipital nerves and vasculature. This reproducible positioning allows accurate depth of placement (assuring production of the prerequisite PNS dermatomal paresthesia required for ONS efficacy) and limits the risk of injury to the occipital artery or nerve(s). In this case series, ultrasonography provided real-time, safe, and reliable placement of ONS electrodes. It also allowed identification of nervous and vascular structures unable to be seen with fluoroscopy, The portable nature of modern ultrasound machines, together with an ever improving pixelation of the Doppler color flow images/real-time measurements, and a lack of radiation exposure make this technology an attractive emerging modality in the field of Neuromodulation.Neuromodulation 04/2010; 13(2):126-30. · 1.19 Impact Factor