Needle track

Other important components of the initial evaluation include a medical evaluation including both a medical history and physical examination. This can identify medical consequences of substance abuse, such as liver impairment from chronic alcohol abuse or sinus complications from cocaine use, as well as reveal needle tracks from a variety of self-injection sites that might not be readily apparent to casual observation. 

Drug intoxication. Cocaine and amphetamine intoxication may cause an agitated paranoid psychotic episode. Physical signs include dilated pupils, slurred speech, ataxia, hyperreflexia, and nystagmus, as well as evidence of drug use (e.g., needle tracks, nasal septum erosion). Vital signs, if obtainable, include elevated blood pressure, pulse rate, and temperature (see also the section The Alcoholic Patient in Chapter 14). 

In another study, AAV-mediated delivery of the lacZ gene by direct injection to brain tumors which were induced from human glioma cells in nude mice showed that 30% to 40% of the cells along the needle track expressed b-galactosidase subsequent delivery of the HS V-tk/IL-2 genes to these tumors with AAV and administration of GCV to the animals for 6 days resulted in a 35-fold reduction in the mean volume of tumors compared with controls by a significant contribution from the bystander effect (72). 

Vectors can be injected into the kidney at the location of choice or at multiple sites either beneath the capsule or into the renal parenchyma. The disadvantage of this technique is that the transgene expression is limited to renal tissue surrounding the needle track and the needle penetration per se can cause cell damage. This approach could be relevant for localized renal tumors where anti-angiogenic, pro-apoptotic, or tumor-suppressive genes could be injected. 

It has been suggested that the development of a sterile abscess represents an idiosyncratic reaction of some individuals, perhaps genetically determined, which causes a granulomatous response to antigens, irrespective of the location of the vaccine (36). Others maintain that it is caused by a contaminated needle track or to vaccine material coating the outside of the needle, resulting from the lack of a proper injection technique. 

In establishing the stereotaxic coordinate system for this atlas we studied sections from over 100 rats. To prepare these sections, we positioned the skull in a standard way (the flat-skull position) and marked the vertical and horizontal planes with needle tracks. We placed anesthetized rats in a Kopf small-animal stereotaxic instrument, and the incisor bar was adjusted until the heights of lambda and bregma were equal. This flat-skull position was achieved when the incisor bar was lowered 3.3 0.4 mm below horizontal zero (Table 1). 

To confirm the stereotaxic orientation of sections in the brain used for this atlas, reference needle tracks were made perpendicular to the horizontal and coronal planes. For brains sectioned in the coronal plane, vertical needle insertions were made at 2.0 mm intervals through the brain, except for the penetrations at 0.7 mm anterior to the interaural line, which was chosen to avoid rupture of a venous sinus. Ten such needle tracks appear on coronal plates of this atlas. Three horizontal needle insertions perpendicular to the coronal plane were made from the posterior of the brain at 1.0, 3.0, and 5.0 mm above the interaural line and approximately 1.0 mm lateral to the midline. The reference tracks from the horizontal needles appear as small holes in coronal sections. 

Frozen brains were sectioned on an American Optical Gryocut microtome at 40 gm. Sections were obtained parallel to the stereotaxic planes by adjusting the angle of cutting until the needle tracks encountered were judged to be parallel to the plane of section. Sections were taken directly from the cryotome knife on... 

Needle penetration Hoppler consistometer, Needle track tester A—>C 34... 

Subcutaneous inoculations are convenient but the response is slower than by the intramuscular route. It is recommended for boosters since it decreases the chances of an anaphylactic shock. The needle (bevel up) is inserted into the fold of the skin, lifted between thumb and forefinger, until the tip of the needle feels free. After the injection the needle track should be pinched to prevent loss of inoculated... 

IV. Diagnosis is simpie when typicai manifestations of opiate intoxication are present (pinpoint pupiis and respiratory and CNS depression), and the patient quickly awakens after administration of naloxone. Signs of intravenous dmg abuse (eg, needle track marks) may be present. 

Careful correlation with prior CT images will help plan the puncture in relation to the markers on the stent graft. Ideally the left side access is used to avoid IVC. However, if necessary the puncture can be done through the IVC. When performed under fluoroscopic guidance it is useful to frequently rotate the X-ray tube from the AP to the lateral projection, and in between, to help in assessing the needle track, and to avoid puncturing the stentgraft. 

Chisolm. R.A..Jones, S.N. and Lees, W.R. (1989) Fibrin sealant as a plug for post liver biopsy needle track. CUn. Radiol, 40, 627-628. 

From a procedural and technical point of view, RFA has to be considered a safe and minimally invasive method. The needles used are typically small (14-17.5 G) compared to needles used for biopsy, complemented by the intrinsic capability of cauterization and coagulation (to avoid bleeding from the needle track and tumour seeding along the track cauterization of the track is recommended). 

Nevertheless, based on the principle of cauterization, the coagulative potential of the thermal ablation procedure itself makes the bleeding of a treated lesion quite unusual. To avoid needle track bleeding it is recommended to perform hot probe repositioning and removal (i.e. needle track ablation). Therefore, regarding the present literature bleeding in total is a rare, in most cases self-limiting, complication with a frequency of no more than 2%. 

After the procedure the needle track is closed with fibrin glue (Tissucol Duo S, Baxter, Wien, Austria). 

In larger lesions, the array is withdrawn and redeployed anteriorly at 1.5- to 2.0-cm intervals into the tumor. After the hooks are fully deployed, the electrode is connected to the RF generator. The heating protocol for all the available needles is provided by the manufacturer. In general, the generator is started at a lower power setting and is subsequently increased in 10-W increments at 1-min intervals. The endpoint of RF application is the appearance of a rapid increase in tissue impedance (Roll-off) around the electrode. When this occurs, the RF application is automatically terminated. This process is repeated starting at 70% of the roll-off power until a second increase of the impedance occurs. Since the time point of the rapid increase in tissue impedance cannot be predicted, the ablation time needed varies dramatically between different tumor sizes and nodules. At the end of the procedure the needle track is ablated to prevent any tumor dissemination. Therefore, the tip has to be unisolated prior to the insertion of the needle. 

Seeding along the needle track with percutaneous minimally invasive tumor treatment modalities has not yet been reported in lung data for liver therapy report seeding to occur along the track in 0.7%-2.3% of hepatocellular carcinoma patients treated with PEI (ISHii et al. 1998). 

Informed consent is obtained from all patient. Prior to LITT treatment all patients undergo CT and a contrast-enhanced MRI study at least 2 days prior to the intervention. After localization of the tumor with CT local anesthesia was achieved with 20-30 ml of 1% mepivacaine (Scandicain, AstraZeneca, Wedel, Germany). Distance to the lesion and the puncture angle are calculated electronically. For targeting of both recurrent nasopharyngeal tumors and pleomorphic adenomas a subzygomatic approach to the lesion was chosen, which provided the best and safest access to the lesion. Lesions of the larynx and the floor of the mouth were punctured directly. After the procedure the needle track was closed with flbrin glue (Tissucol Duo S, Baxter, Vienna, Austria). 

Fig. 19.8. Sonographically guided renal biopsy using the needle guide attached to the transducer the dotted lines show the path of the needle and help to guide the biopsy needle (18 gauge core cut needle, performed with a biopsy gun) for safe puncture as well as retrieval of sufficient specimen material. The image is retrospectively taken from the cine-loop analysis of the needle movement during biopsy (usefiil for documentation and analysis of the procedure) The callipers mark the length of the intraparenchymal needle track (1.7 cm)...

The most common complication associated with core-needle biopsy is a fall in hemoglobin (20%) (VujANic et al. 2003). Massive tumor bleeding, tumor rupture leading to death or needle track recurrences have been infrequently reported (Dykes et al. 1991 Saarinen et al. 1991 Lee et al. 1995 Skoldenberg et al. 1999 Vujanic et al. 2003) and remain exceptional in trained hands. 

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