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At least 19 recordsLinked to original sources
PubMed2004

Computed tomography-guided transthoracic fine-needle aspiration in diagnosis of lung cancer: a comparison of single-pass needle and multiple-pass coaxial needle systems and the value of immediate cytological assessment.

OBJECTIVES: The aim of the present study was to compare single-pass needle and multiple-pass coaxial needle systems and to evaluate the value of immediate cytological assessment during the procedure in the diagnosis of lung cancer with CT-guided transthoracic fine-needle aspiration. METHODOLOGY: One hundred and forty-three consecutive patients who underwent CT-guided transthoracic fine-needle aspiration were divided into three groups. In the first group (group A, 48 patients), a single-pass needle was used for aspiration, but immediate cytological examination was not performed. In the second group (group B, 48 patients), a single-pass needle was used for aspiration and a pathologist immediately assessed the adequacy of the sample obtained. In the third group (group C, 47 patients), a multiple-pass coaxial needle was used for aspiration and a pathologist immediately assessed the adequacy of the sample obtained. RESULTS: The mean number of fine-needle aspirations was 1.25 in group A, 1.39 in group B and 1.34 in group C (group A vs group B, P = 0.08). The diagnostic accuracy was 83.3, 97.9 and 100.0%, respectively (group A vs group B, P = 0.03; group B vs group C, P > 0.05). Although immediate cytological assessment resulted in adequate samples being obtained from all patients in groups B and C, adequate samples were obtained in 41 of 48 patients (85.4%) in group A (P = 0.004). There was no statistically significant difference among the groups with respect to the rate of pneumothorax. CONCLUSIONS: A single-pass needle technique in transthoracic fine-needle aspiration is preferred because there is no significant difference between single-pass needle and multiple-pass coaxial needle systems with respect to the diagnostic accuracy and the complication rate and, in addition, the single-pass needle has a lower cost. The results of the present study suggest that immediate cytological assessment during the procedure reduces an inadequate sampling rate, thus increasing the diagnostic accuracy of the procedure.

Adult↗
PubMed2001

Twenty-one-gauge needles provide more cellular samples than twenty-five-gauge needles in fine-needle aspiration biopsy of the thyroid but may not provide increased diagnostic accuracy.

The technique of fine-needle aspiration (FNA) biopsy of the thyroid is important to evaluate malignancy in thyroid nodules. Eighty-five percent of thyroid FNA procedures lead to sufficient cellular material for diagnosis. With more cells aspirated, the chance of sufficiency for diagnosis increases. Large-bore needles lead to more cellular material being aspirated but bloodier specimens that may interfere with cytologic interpretation. Small-bore needles may result in too few cells for diagnosis. We conducted a randomized prospective study contrasting 21-gauge and 25-gauge needles in the evaluation of 50 consecutively enrolled nodules at our institution. In our investigation, 21-gauge needles more frequently provided superior biopsy specimens (50%) than did 25-gauge needles (18%). In the remaining specimens (32%), the 21-gauge and 25-gauge needles provided similar cellular material. The rate of sufficient samples was the same. We conclude that use of 21-gauge needles results in more cellular specimens but may not result in increased diagnostic accuracy.

Biopsy, Needle↗
PubMed1998

A randomized controlled trial comparing a 21 G needle with a 23 G needle for fine needle aspiration of breast lumps.

A randomized study was performed on patients in whom the clinical decision had already been made to excise a breast lump. The objective was to assess the difference in diagnostic results of 21 and 23 G needles in the fine needle aspiration cytology (FNAC) of breast lumps. Following induction of anaesthetic, (local or general), FNAC was performed with either a 21 or 23 G needle. The breast lump was then excised and the histology and cytology results analysed routinely. One hundred and twenty-five excised breast lumps were included. Sixty-one had FNAC performed with a 21 G needle and 64 had FNAC performed with a 23 G needle. Of the 61 21 G FNAC, histology revealed 45 breast cancers. Of the 64 23 G FNAC, 50 patients had breast cancer. There was no statistical difference between these two results. There is no difference in the cytological yield when a 21 G needle is compared with that of a 23 G needle.

Biopsy, Needle↗
PubMed1994

A decline in HIV-infected needles returned to New Haven's needle exchange program: client shift or needle exchange?

The New Haven needle exchange program experienced a significant decline in the fraction of returned needles containing human immunodeficiency virus 1 (HIV-1) proviral DNA. Is this decline due to the operations of the needle exchange or to a shift in clients? Analysis of demographic and behavioral data revealed that only one variable, the race of participating clients, changed significantly over time. However, HIV-1 prevalences in needles given to Whites and to non-Whites were not statistically different. Thus, client shift cannot be responsible for the decline in the observed HIV prevalence in needles. Instead, needle circulation times were a significant predictor of HIV prevalence.

Connecticut↗
PubMedDate not supplied

Coarse needle biopsy versus fine needle aspiration biopsy in the diagnosis of focal lesions of the liver. Ultrasonically guided needle biopsy in suspected hepatic malignancy.

In 55 patients with ultrasonically demonstrated suspected hepatic malignancy, a fine needle aspiration biopsy and a coarse needle biopsy of the same focal lesion were performed under ultrasonic guidance. In 41 of 48 cases with proven malignancy, both biopsies were positive. In the remaining seven cases, only the fine needle aspiration biopsy yielded malignant cells. Tumor typing was possible in 2 primary and 33 metastatic tumors by examination of either the cytologic or the histologic specimen; an additional 6 metastatic tumors could be typed only by evaluation of the histologic specimen. Grading of six adenocarcinomas was performed with higher accuracy in the histologic than in the cytologic specimen. Exact determination of the primary site was not possible in metastatic tumors by use of either type of needle biopsy specimen. Since the less traumatic fine needle aspiration biopsy requires fewer prebiopsy precautions and has other advantages, the coarse needle biopsy should be restricted to the few cases in which the former does not yield sufficient information.

Adenocarcinoma↗
PubMed2003

Are needle-free injections a useful alternative for growth hormone therapy in children? Safety and pharmacokinetics of growth hormone delivered by a new needle-free injection device compared to a fine gauge needle.

The clinical safety, use and pharmacokinetics of a new needle-free device for delivery of growth hormone (GH) were compared with those of conventional needle injection devices. In an open-label, randomized, 4-period crossover study, 18 healthy adults received single subcutaneous injections of Genotropin administered by the Genotropin ZipTip needle-free device and by conventional injection. Bioequivalence was established between the devices. In a separate open-label, randomized, multicenter, 2-period crossover study, pediatric patients underwent 2-weeks Genotropin treatment administered by the Genotropin ZipTip and by a fine-gauge needle device (>95% used the Genotropin Pen). In total, 128/133 patients who were treated completed the study. Genotropin ZipTip was well tolerated and >50% of patients found no difference between the devices for all parameters assessed. After study completion, >20% patients preferred to continue using Genotropin ZipTip. Although statistical analyses demonstrated superiority of the Genotropin Pen versus Genotropin ZipTip for bleeding, pain, soreness, and bruising, Genotropin ZipTip was considered to provide a safe and bioequivalent alternative to needle injection.

Adolescent↗
PubMed1991

[Study on usefulness of an aspirating biopsy needle (Vacu-Cut) and an automatic biopsy needle (Biopty-Cut) for renal biopsy--comparison with a Tru-Cut biopsy needle].

Our medical team conducted the percutaneous renal biopsy, using an aspirating biopsy needle (Vacu-Cut) in 101 cases, and an automatic biopsy needle (Biopty-Cut) in 82 cases. Thereafter, we examined the usefulness of the two types of needles in comparison with that of Tru-Cut used in 101 cases. The test confirmed that in the cases of Vacu-Cut, 7.6 glomeruli (p less than 0.01), on the average, existed in LM specimen; 9.0 glomeruli (ns), Biopty-Cut, and 10.7 glomeruli, Tru-Cut, respectively. However the incidence of cases containing more than 5 glomeruli was not significant statistically between Vacu-Cut/Biopty-Cut and Tru-Cut. The incidence that each type of needles obtained more than one glomerulus in IF specimen was as follows: 73.3%, Vacu-Cut (p less than 0.05), 81.7%, Biopty-Cut (ns), 87.1%, Tru-Cut, respectively. As for in EM specimen, 61.4%, Vacu-Cut (ns), 67.1%, Biopty-Cut (ns), and 70.3%, Tru-Cut, respectively. As for complications, in the cases of Vacu-Cut and Biopty-Cut, gross hematuria and post-biopsy pain occurred in 6.9 to 9.8% (p less than 0.01- p less than 0.05), whereas in Tru-Cut, they occurred in 20.7 to 24.8%. As for blood pressure lowering (less than 90 mmHg) and anemia (the cases in which blood transfusion was required), 0%, Vacu-Cut and Biopty-Cut, 2 to 3%, Tru-Cut, respectively. As for fever, Vacu-Cut 0%, Vacu-Cut (p less than 0.01), 3.7%, Biopty-Cut (ns), and 7.9%, Tru-Cut, respectively. The above findings lead to conclusion that both Vacu-Cut and Biopty-Cut are useful instruments for renal biopsy.

Adolescent↗
PubMed1993

Fine-needle aspiration anchor. A simple device to prevent needle-stick injury at fine-needle aspiration.

Pathologists and clinicians performing fine-needle aspiration for cytologic diagnosis are at risk of finger injury by the needle during the aspiration procedure. To prevent this occurrence and its accompanying potential for transmitting serious pathogens such as the human immunodeficiency virus and hepatitis B virus, we have designed a simple acrylic device (fine-needle aspiration anchor) consisting of two curved prongs with an attached handle, to take up the functions of the fingers for stabilization of the target lesion. Use of the fine-needle aspiration anchor on more than 1000 patients with various mass lesions has confirmed enhanced immobilization of the lesions for aspiration, safety for the person performing the procedure, and excellent patient acceptance.

Biopsy, Needle↗
PubMed1997

[Fine needle capillary cytology versus fine needle aspiration cytology--a comparison of quality between puncture techniques in the ENT area].

BACKGROUND: Needle aspiration is currently a widely used technique in the diagnosis of unclear lesions in the head and neck region. We present a modified technique of fine needle biopsy in ENT, "fine needle capillary technique". The basics of this technique were developed by Zajdela and coworkers (1987) as a cytological method of fine needle biopsy in benign and malignant mammary tumors. Fine needle capillary technique does not require aspiration of cell samples via negative pressure created by a syringe. A thin 25 G needle (outer diameter 0.50 mm, length 25 mm) is introduced into the lesion with one hand. The cells are detached by the cutting edge of the needle and are conducted into the lumen by capillary force. The needle is removed and the cellular material is expelled onto a glass slide, spread, and immediately fixed. METHOD: In a series of 166 patients with unclear lesions in the head and neck region, we compared the fine needle capillary technique with the classic fine needle aspiration technique in each patient. Regarding quality and assessment of the cytological smear the fine needle capillary technique proved clearly superior in most of the cases. Lymph nodes, tumors of the salivary glands, thyroid glands, branchiogenic cysts, one atheroma, one lipoma, and one skin metastasis of a squamous cell carcinoma were punctured. RESULTS: In our study fine needle capillary technique showed a very good quality of the cytological smear in 24.7% of all cases, while fine needle aspiration technique reached 12.1% only. A good quality was obtained in 51.2% with fine needle capillary technique and in 51.8% with fine needle aspiration technique, poor quality in 24.1% with fine needle capillary technique and in 36.1% with fine needle aspiration technique. Nondiagnostic cytology was obtained in 21.7% with fine needle capillary technique and in 32.5% with fine needle aspiration technique. Both techniques together showed insufficient material in 10.8%. The quality of the cytological smear in each region was always better with fine needle capillary techniques than with fine needle aspiration technique except five punctures of the submandibular gland. Of 166 patients 113 (68.1%) underwent surgery, and a correlation of the cytologic report to the surgical specimen showed agreement in 95.7% with fine needle capillary technique and in 90.5% with fine needle aspiration technique. In 17.7% with fine needle capillary technique and in 25.7% with fine needle aspiration technique it was not possible to compare the cytological smear with the histological results because of poor quality of the cytological smear. In four cases (4.3%) with fine needle capillary technique the cytological diagnosis was wrong. With fine needle aspiration technique, a wrong diagnosis occurred eight cases (9.5%). CONCLUSIONS: Fine needle capillary technique offers several advantages. Without aspiration trauma to cells and tissues is reduced. Less blood in the samples results in higher quality of the cytological smear. These circumstances make it easier for the pathologist to comment the cytological findings. The handling of the needle is practiced with a wrist movement and not from the shoulder joint as in aspiration method using the Cameco syringe holder. This allows for a more sensitive puncture technique touching the lesion during sampling with the finger tips. The puncture causes less pain than the aspiration technique. Our results demonstrate that fine needle capillary technique is the better method of fine needle biopsy in the head and neck region.

Biopsy, Needle↗
PubMedDate not supplied

Comparative flow rates of saline in commonly used spinal needles including pencil-tip needles.

BACKGROUND AND OBJECTIVES: Certain characteristics of spinal needles that can influence their clinical usefulness were examined, namely, flow rates, internal diameters, and size of orifices of pencil-type needles. METHODS: Flow rates of 0.9% sodium chloride solution were measured in spinal needles with an infusion pressure of 10 mmHg at isothermic and steady-state conditions. In 15 different types, a new needle was used for each experiment, and 6 experiments were performed with each needle type for a total of 90 experiments. The Hagen-Poisseuille Law for laminar flow was used to calculate the internal diameters. RESULTS: The flow rates of needles of the same gauge varied considerably depending on the manufacturer. Compared with 26-gauge ultrathin-wall spinal needle produced by the same manufacturer (Braun, Bethlehem, Pennsylvania), the flow rate through 29-gauge spinal needle was 18% that of the former needle. The flow rate through 27-gauge Quincke Whitacre needle (Becton Dickinson, Rutherford, New Jersey) was not statistically different from that through 26-gauge needle by the same manufacturer. By arbitrarily choosing < or = 2 seconds to be the in vitro desirable period for saline to traverse the needle from one end to the other, all needles with the exception of 29-gauge and standard 26-gauge Quincke Braun needles met this criterion. The length and size of the orifices of Whitacre needles were found to be significantly smaller than those of Sprotte needles (Havel, Cincinnati, Ohio). The orifice of Sprotte needle was longer than the known thickness of the dura while that of the Whitacre needle was smaller. CONCLUSIONS: Needles of the same gauge do not necessarily have the same flow rate. Flow rate correlates well with internal, not external, diameter. By considering < or = 2 seconds to be the desirable time for saline to traverse a spinal needle, all, except two, meet this criterion. The orifice of Whitacre needle has more desirable features than that of Sprottle needle. Anesthesiologists are encouraged to use 27-gauge needles since their flow rate is not slower than that of 26-gauge needles.

Needles↗
PubMed1996

No additional metal particle formation using the needle-through-needle combined epidural/spinal technique.

BACKGROUND: Combined epidural/spinal analgesia utilizing a needle-through-needle technique has become very popular in anesthesia. However, findings of concave deformities at the orifice of Tuohy needles after spinal needle passage have raised concerns that metal fragments might be deposited within the epidural space. This study was proposed to investigate whether the needle-through-needle technique does produce metallic flecks. METHODS: Ten unused Tuohy and Hustead epidural needles were inspected microscopically and photomicrographed prior to flushing saline through each into a single tissue culture well. After drying, a single pass was made with a 120 mm 24-gauge Sprotte needle through each epidural needle to maximal extension while the orifice was within another tissue culture well. Each needle was again flushed into a third well before reexamination and photomicroscopy. Each of the wells was inspected for metallic particles by microscopy. Additional freshly unpackaged Tuohy needles were microscopically examined after exposure to a magnetic field. RESULTS: Comparison of micrographs before and after needle experiments revealed concave deformities at the orifice of all the Tuohy and Hustead needles. No particles were observed in either of the two saline-flushed wells or within the well in which the needle-through-needle passes were made. Inspection of unused Tuohy needles exposed to a magnetic field revealed metal filings "standing up" along the bevel of every needle examined. CONCLUSIONS: Metallic particles are not produced by the needle-through-needle technique. However, metal particles are an apparent contaminant of all epidural needles and are probably routinely introduced into patients when the needle is placed.

Analgesia, Epidural↗
PubMed1999

Aspiration needle biopsy in preoperative selection of thyroid nodules defined at fine-needle aspiration as microfollicular lesions.

The palpable thyroid nodules that are diagnosed as microfollicular by fine-needle aspiration cytologic analysis are usually excised for the low probability that the nodule is a well-differentiated follicular cancer. The authors retrospectively assess the use of aspiration needle biopsy (either 16- or 18-gauge needles) in the preoperative selection of the nodules diagnosed as microfollicular at fine-needle aspiration (either 20- or 22-gauge needles). Aspiration needle biopsy is a type of large needle biopsy that is a relatively easy and innocuous method of obtaining tissue fragments for preoperative histologic examination of palpable thyroid nodules. From 1980 through 1996, 6,314 patients with palpable thyroid nodules were examined by fine-needle aspiration; 29.5% of these nodules were also examined preoperatively by aspiration needle biopsy. Of all the patients with nodules, 6% received a fine-needle aspiration diagnosis of microfollicular nodule. Two hundred sixty of the 380 nodules (68%) that were diagnosed as microfollicular at fine-needle aspiration were also examined by aspiration needle biopsy; inadequate specimens were obtained in 17% of cases; pure microfollicular structure was confirmed by aspiration needle biopsy in 35% of the nodules; and aspiration needle biopsy showed the remaining 48% to contain a macrofollicular component suggesting a benign hyperplastic lesion. Seventeen nodules that were found to be microfollicular at fine-needle aspiration cytologic analysis and micromacrofollicular at aspiration needle biopsy were excised and the postoperative result was benign in all cases. Twenty-five nodules diagnosed as microfollicular either on both fine-needle aspiration and aspiration needle biopsy were excised and the postoperative diagnoses were benign (20 nodules) or malignant (5 nodules). These data indicate that aspiration needle biopsy can be used for preoperative selection of the nodules that are microfollicular at fine-needle aspiration by identifying the nodules with high probability of being malignant and thus contributing to the reduction in the number of surgical operations for benign nodules.

Adenocarcinoma, Follicular↗
PubMed2002

Dependence of needle architecture and chemical composition on canopy light availability in three North American Pinus species with contrasting needle length.

Morphology and chemical composition of needles of shade-intolerant southern conifers (Pinus palustris Mill. (mean needle length +/- SD = 29.1 +/- 4.1 cm), P. taeda L. (12.3 +/- 2.9 cm) and P. virginiana Mill. (5.1 +/- 0.8 cm)) were studied to test the hypothesis that foliage acclimation potential to canopy light gradients is generally low for shade-intolerant species, and in particular, because of mechanical limitations, in species with longer needles. Plasticity for each needle variable was defined as the slope of the foliar characteristic versus irradiance relationship. A novel geometrical model for needle area and volume calculation was employed for the three-needled species P. palustris and P. taeda. Needle thickness (T) strongly increased, but width (W) was less variable with increasing daily integrated quantum flux density averaged over the season (Q(int)), resulting in changes in cross-sectional needle shape that were manifested in a positive relationship between the total to projected needle area ratio (A(T)/A(P)) and Q(int) in the three-needled species. In contrast, cross-sectional needle geometry was only slightly modified by irradiance in the two-needled conifer P. virginiana. Needle dry mass per unit total needle area (M(T)) was positively related to Q(int) in all species, leading to greater foliar nitrogen contents per unit area at higher irradiances. Separate examination of the components of M(T) (density (D) and the volume (V) to A(T) ratio; M(T) = DV/A(T)) indicated that the positive effect of light on M(T) resulted solely from increases in V/A(T), i.e., from increases in the thickness of foliage elements. Foliar chlorophyll content per unit mass increased with increasing Q(int), allowing an improvement in light-harvesting efficiency in low light. The variables characterizing needle material properties (D, the dry to fresh mass ratio, and needle carbon content per unit mass) were generally independent of Q(int), suggesting that needles were less stiff and had greater tip deflections under their own weight at lower irradiances because of smaller W and T. Comparisons with the literature revealed that plasticity in foliar characteristics tended to be lower in the studied shade- intolerant species than in shade-tolerant conifers, but plasticity among the investigated species was unaffected by needle length. However, we argue that, because of mechanical limitations, plastic changes in needle cross section in response to low irradiance may decrease rather than increase light-interception efficiency in long-needled species.

Biomass↗
PubMed2001

In-vitro visualization of biopsy needles with ultrasound: a comparative study of standard and echogenic needles using an ultrasound phantom.

AIM: To demonstrate the circumstances where echogenically enhanced biopsy needles confer an increase in visualization during ultrasound-guided biopsy using an in-vitro experiment. MATERIALS AND METHODS: An experiment using both standard and echogenically enhanced needles was conducted in a purpose built interventional phantom. The needle tip echogenicity and shaft visualization was recorded at different angles (20 and 60 degrees ) between the ultrasound probe and needle. The needle tip echogenicity was also recorded in four different angles of bevel rotation. The experiment was performed using a total of 18 different needles of 18 and 20 gauge. RESULTS: The experiment confirmed some previous findings. The needle was better visualised at an angle of approximately 60 degrees to the probe. The needle tip was optimally visualized with the bevel facing the transducer or 180 degrees to it. Needle tip movement improved conspicuity. Using an optimal angle of approach (60 degrees ) the use of an echogenic needle did not confer any increase in conspicuity. If the transducer to needle angle was suboptimal (20 degrees ) then there was increased visualization of some echogenically enhanced needles. CONCLUSION: Optimisation of the conditions prior to ultrasound-guided needle biopsy will increase the visualization of the chosen device thus aiding the interventionalist. Needle gauge, bevel position, movement of the needle and the probe to needle angle all affect conspicuity. Needle coating or roughening does not improve tip visualization if the angle between the needle and probe can be optimized (60 degrees ). In unfavourable situations when the angle is suboptimal (20 degrees ), we have shown that echogenic enhancement of the needle tip can make it more visible.

Biopsy, Needle↗
PubMedDate not supplied

A trigonometric analysis of needle redirection and needle position during neural block.

BACKGROUND AND OBJECTIVES: Successful regional anesthesia involves a three-dimensional visualization of anatomy and an informed approach to needle placement and repositioning. This study trigonometrically examines the relationship between needle insertion angle and resultant needle position. METHODS: Needle position during advancement of 2-inch (5.1-cm), 3 1/2-inch (8.9-cm), and 5-inch (12.7-cm) needles was trigonometrically determined. Starting at 90 degrees, the angle of needle insertion theta (measured from the perpendicular) was decreased in 5 degrees and 10 degrees increments, and the resultant change in needle position was calculated by using a computer model. Needle depths relevant to the three needle lengths were studied and ranged from 0.5 to 11.0 cm. The effects of needle insertion angle, redirection angle, and depth on resultant needle position were evaluated. RESULTS: The mean change in needle position was significantly less with a 5 degree redirection of the needle than with a 10 degree needle redirection. In addition, the mean change in needle position was highly correlated with increasing needle depth and acute angle of needle insertion. CONCLUSIONS: Incremental needle redirection of 5 degrees allows a precise survey of neural and adjacent anatomy and results in approximately one half the change in needle position occurring with a 10 degree angle of redirection. However, a 10 degree angle of redirection may result in walking over the desired neural structure.

Humans↗
PubMed2002

Variation in specific needle area of old-growth Douglas-fir in relation to needle age, within-crown position and epicormic shoot production.

Variation in specific needle area (SNA; cm2 projected fresh needle area g-1 oven-dried needle weight) was investigated in relation to needle age, within-crown position and epicormic shoot production in 450-year-old Douglas-fir (Pseudotsuga menziesii Mirb. (Franco) var. menziesii) trees. Specific needle area decreased with increasing needle age. The magnitude and rate of change in SNA with needle age were greatest for lower-crown branches, and decreased toward the middle- and upper-crown branches. For all branches, there was no difference between regular and epicormic shoots in the relationship between SNA and needle age. Specific needle area decreased with increasing distance from branch base, and this relationship was significant for the majority of needle age classes of the upper- and middle-crown branches. In the lowercrown branches, SNA did not vary with distance from branch base for the majority of needle age classes. For all branches, there was no difference between regular and epicormic shoots in the relationship between SNA and distance from branch base for the majority of needle age classes. These results indicate that renewal of foliage by epicormic shoot production maintains needle quality. Branch SNA increased linearly with decreasing height in the crown at a mean rate of 0.951 +/- 0.110 cm2 g-1 per vertical meter. Total needle area of branches was estimated from total needle dry weight taking into account within-branch variation in SNA. Analyses of allometric relationships between branch size and foliage amount (needle area and needle dry weight) showed that branch length was a better predictor of foliage amount than branch diameter for old Douglas-fir trees. Total needle dry weight and needle area of the sample trees, estimated from branch length and branch height and taking into account vertical within-crown variation in branch SNA, ranged from 42.4 to 154.2 kg and from 246.2 to 816.0 m2 per tree, respectively.

Plant Leaves↗
PubMed2004

The long core needle with an end-cut technique for prostate biopsy: does it really have advantages when compared with standard needles?

OBJECTIVE: To evaluate the failure rate, core length and fragmentation rate for each different stroke length of the end-cut (BioPince) needle in order to show the performance of the needle for different stroke lengths and compare these with the standard side-notch needle. METHODS: TRUS guided biopsy of the prostate was performed on 86 consecutive men between June 2002 and May 2003. The patients were randomized into two groups with 43 men in each group. Patients in group A underwent 8 core biopsy with the end-cut needle in different stroke lengths; 13, 23 and 33mm respectively. Patients in group B underwent 8 core biopsy with the side-notch needle. The cores have been evaluated and compared for failure rates, core lengths, number of core lengths under 5mm and fragmentation rates. RESULTS: When the end-cut needle was used, a significant number of failure rates was noted; with an overall failure rate of 16%. The failure rates were 26% for 13mm stroke length, 18% for 23mm stroke length and 10% for 33mm stroke length respectively. These failure rates showed statistically significant difference from standard needle for overall and for every separate stroke length ( p<0.001 for all). Standard needle and the cores taken with 33mm stroke length of the end-cut needle had similar low fragmentation rates while 13 and 23mm stroke lengths had higher rates. Of the overall cores taken by BioPince needle, 46/344 (13%) of the cores were shorter than 5mm and this was significantly higher than the standard needle with 3/344 cores less than 5mm ( p<0.001). The end-cut needle when used with the 33mm stroke length has improved the core length by 68% according to the standard side-notch needle. CONCLUSIONS: Our results showed that the performance of the end-cut needle worsens with decreased stroke lengths. The end-cut needle showed high failure rates which necessitates new punctures for taking a core. Additionally, the fragmentation rates are not lower than the standard needle and it has higher rates of taking small core samples. The only significant advantage of this needle over the standard needle is taking longer cores when it has been used at 33mm stroke lengths.

Adult↗
PubMed1990

Needle growth in Sitka spruce (Picea sitchensis): effects of nutrient deficiency and needle position within shoots.

Needle development and shoot growth were studied in 14- and 20-year-old Sitka spruce (Picea sitchensis (Bong.) Carr.) planted on an oligotrophic peat and fertilized with N, P and K (control), N and P (-K), N and K (-P) or unfertilized (-NPK). Shoot extension, needle number, and the size and number of needle cells were observed throughout the season. Beginning with bud burst in early May, needle growth continued for nine weeks in the control treatment. Needle growth in the mineral deficiency treatments terminated at the same time as in the controls, although it did not begin until up to three weeks later than in the control trees. Needles developed acropetally along the shoot, with basal needles completing their development first. Cell division in needles of control trees lasted about 3 weeks, with cell expansion continuing for a further 3 weeks. Initial mean cell cycle times were shortest for proximal needles following bud burst, but lengthened as the season progressed. Cell number increased from 6600 in the primordia to 200 000 in mature needles. Final needle dimensions and cell number varied according to the position of the needle on the shoot. The largest needles with the most cells were near the middle of the shoot. Relative to the controls, all mineral deficiency treatments reduced shoot length, bud and needle dimensions, and needle cell number, particularly the -P treatment. Potassium and P deficiency treatments reduced primordial cell number by up to 42%, whereas final mean cell size was 30% greater in the -P treatment, 17% greater in the -NPK treatment, but 14% smaller in the -K treatment. Mean cell size was constant for needles at all positions in any particular treatment at any time, so that final needle size was determined by cell number alone. Needle dry weight/fresh weight ratio continued to increase until early August, with significantly higher ratios in the -K and -P treatments than in the controls.

Journal Article↗