results the rate of first-time successful spinal needle insertion was not significantly different between the clsp and tsp groups (62.9% versus 55.7%, p > 0.05). ease of landmark palpation in the clsp group was not significantly different from that in the tsp group (86.7% versus 76.4%, p > 0.05). the number of needle-bone contacts in both groups were not significantly different (p > 0.05). the ...

A virtual sensor is developed for the online estimation of needle tip deflection during permanent interstitial brachytherapy needle insertion. Permanent interstitial brachytherapy is an effective, minimally invasive, and patient friendly cancer treatment procedure. The deflection of the needles used in the procedure, however, undermines the treatment efficiency and, therefore, needs to be minim...

BACKGROUND Premedication with sedatives can decrease the discomfort associated with invasive anesthetic procedures. Some researchers have shown that acupressure on the acupuncture extra 1 point is effective for sedation. We investigated whether acupressure on the extra 1 point could alleviate the pain of needle insertion. METHODS We investigated the effect of acupressure at the extra 1 point ...

OBJECTIVES Local anesthetic infiltration is also a process of a painful process itself. INJEX™ technology, known as "Needle-free" drug delivery system, was designed for reducing the pain associated with cutaneous procedures. We conducted a prospective, randomized trial to evaluate the application of lidocaine with INJEX™ system and 27-gauge needle. METHODS A total of 60 consecutive patients w...

A needle-tissue interaction model is an essential part of every needle insertion simulator. In this paper, a new experimental method for the modeling of needle-tissue interaction is presented. The method consists of measuring needle and tissue displacements with ultrasound, measuring needle base forces, and using a deformation simulation model to identify the parameters of a needle-tissue inter...

Needle insertion procedures are commonly used to treat and to diagnose prostate cancer. Surgical simulation systems can be used to estimate prostate deformation during preand intra-operative needle insertion planning. Such systems require a model that can accurately predict the prostate deformation in real time. In this study, we present a prostate model that incorporates the anatomy of the mal...

Needle tip visualization is fundamental to the safety and efficacy of ultrasound-guided regional anesthesia (UGRA). It can be extremely challenging especially at steep insertion angles. We assessed whether an echogenic needle improved tip visibility during UGRA by anesthesiologists performing their normal in-plane technique. The visibility of the Pajunk Sonoplex (echogenic) and the Pajunk Unipl...

BACKGROUND Image-guided robots are manipulators that operate based on medical images. Perhaps the most common class of image-guided robots are robots for needle interventions. Typically, these robots actively position and/or orient a needle guide, but needle insertion is still done by the physician. While this arrangement may have safety advantages and keep the physician in control of needle in...

A methodology for estimating the force distribution that occurs along a needle shaft during insertion is described. An experimental system for measuring planar tissue phantom deformation during needle insertions has been developed and is presented. A two dimensional linear elastostatic material model, discretised using the Finite Element Method, is used to derive contact force information that ...

Models that predict soft tissue deformation during needle insertion could improve the accuracy of needle based medical procedures. In an effort to establish a method for defining and validating such models, we present an experimental setup including hardware and software for recording and measuring the time-dependent, 3D deformation that occurs as a needle is inserted into soft material. Algori...