Regional anesthesia for breast cancer surgery: which block is best? A review of the current literature.

Breast cancer is the most common type of cancer worldwide. Fortunately, continual advances in diagnosis and treatment are resulting in increased survival rates. Earlier detection and treatment, to include surgical resection, can greatly improve patients outcomes. However, due to the complex innervation of the breast, management of postoperative pain has proven difficult in the past. Approximately, half of all women who undergo breast cancer surgery report postoperative pain syndrome. The paravertebral block has long been the anesthesiologist's choice for mitigating pain during and after the procedure. Newer techniques such as the pectoral nerve block and erector spinae plane block may prove to have some additional benefits. This literature review compares the risks, benefits and specific uses of these three regional nerve blocks in women undergoing breast cancer surgery. It aims to better inform anesthesiologists when they are choosing which technique is best for their patients.

Breast cancer is the most common type of cancer worldwide with 2 million new cases each year. Approximately 12% of women are diagnosed with breast cancer at some point in their lives. Part of breast cancer treatment often involves surgery to remove a mass. This can cause pain in both the short and long term. There are multiple different kinds of procedures a person can have done that may decrease the pain, they have from that surgery. These procedures are called nerve blocks. This article examines how well different nerve blocks decrease pain from breast cancer surgery. The nerve blocks we review in this article are called paravertebral blocks, pectoral nerve blocks and erector spinae plane blocks. They all block pain from breast surgery in slightly different ways. The decision of which block is best rests on the person performing the block.

Improving maraviroc oral bioavailability by formation of solid drug nanoparticles.

Oral drug administration remains the preferred approach for treatment of HIV in most patients. Maraviroc (MVC) is the first in class co-receptor antagonist, which blocks HIV entry into host cells. MVC has an oral bioavailability of approximately 33%, which is limited by poor permeability as well as affinity for CYP3A and several drug transporters. While once-daily doses are now the favoured option for HIV therapy, dose-limiting postural hypotension has been of theoretical concern when administering doses high enough to achieve this for MVC (particularly during coadministration of enzyme inhibitors). To overcome low bioavailability and modify the pharmacokinetic profile, a series of 70 wt% MVC solid drug nanoparticle (SDN) formulations (containing 30 wt% of various polymer/surfactant excipients) were generated using emulsion templated freeze-drying. The lead formulation contained PVA and AOT excipients (MVCSDNPVA/AOT), and was demonstrated to be fully water-dispersible to release drug nanoparticles with z-average diameter of 728 nm and polydispersity index of 0.3. In vitro and in vivo studies of MVCSDNPVA/AOT showed increased apparent permeability of MVC, compared to a conventional MVC preparation, with in vivo studies in rats showing a 2.5-fold increase in AUC (145.33 vs. 58.71 ng h ml-1). MVC tissue distribution was similar or slightly increased in tissues examined compared to the conventional MVC preparation, with the exception of the liver, spleen and kidneys, which showed statistically significant increases in MVC for MVCSDNPVA/AOT. These data support a novel oral format with the potential for dose reduction while maintaining therapeutic MVC exposure and potentially enabling a once-daily fixed dose combination product.

A Retrieval Analysis of Impingement in Dual-Mobility Liners.

BACKGROUND: Implant-related impingement is likely a major causative factor of total hip arthroplasty (THA) instability. Dual-mobility (DM) cups can theoretically improve stability in THA, but impingement rates with DM cups are not well studied. We examined retrieved DM THA liners to determine if less evidence existed for prosthetic impingement between the neck and the polyethylene liner than historical studies from our institution on fixed-bearing THAs. METHODS: DM components from 93 THAs were identified from 164 THAs whose DM components were revised between 2008 and 2015 through our institutional review board-approved implant retrieval program. The mean age was 63 ± 11 years, mean body mass index was 30 ± 7 kg/m2, and mean length of implantation was 2.08 ± 1.89 years. Two independent graders scored each liner for the presence and severity of impingement. Radiographs were evaluated for inclination, anteversion, change in leg length, and combined offset. RESULTS: Only 21.5% (20/93) of DM cups showed evidence of impingement compared to 77% (75/97) of fixed-bearing cups found in a previous study performed at our institution (P < .001). Of the revision components, 35.2% (5/14) demonstrated evidence of impingement compared to 19.7% (14/71) implanted in primary surgery (P = .189). In the cohort revised for instability, the rate of impingement was 35.3% (6/17); for the implants revised for any other reason, the impingement rate was 18.4% (14/77) (P = .126). CONCLUSION: This study demonstrates that DM liners significantly reduce the rate of impingement (21.5%) when compared to fixed-bearing liners (77%).

Polished, Collarless, Tapered, Cemented Stems for Primary Hip Arthroplasty May Exhibit High Rate of Periprosthetic Fracture at Short-Term Follow-Up.

BACKGROUND: Cemented stems are designed to follow 1 of 2 principles of fixation: composite beams or slide taper. Stems in the latter category have a collarless, polished, tapered (CPT) design and subside into the cement mantle, creating hoop stresses. We compared the rate of periprosthetic fracture (PPF) of stem designed with these 2 principles of fixation. In addition, we examined radiographic factors that may predispose to the development of PPF. METHODS: We retrospectively reviewed all patients who underwent primary THA by a single surgeon using highly polished cemented stems. PPF rates were compared between CPT stems (follow-up, 21 months; standard deviation [SD], 22) and composite beam stems (follow-up, 21.7 months; SD, 26). Demographic data were compared between patients with and without a PPF. Three preoperative radiographic parameters (canal bone ratio [CBR], canal-calcar ratio, and canal flare index), stem alignment, and cement mantle were compared in match-paired patients with and without a PPF (1:34). RESULTS: Seven of 1460 THA patients developed a PPF (0.479%); 4 hips of 185 with a CPT stem (2.2%); and 3 of 1275 hips with a composite beam stem (0.23%; P = .0064). Three of the 4 PPFs in the CPT group and none in the composite beam group were classified as Vancouver B2. The CBR in patients with a PPF was 0.50 (SD, 0.07) and 0.43 (SD, 0.07) in the match cohort of hips without PPF (P = .013). CONCLUSION: CPT stems may be associated with a higher risk of PPF that often require reoperation. An increased CBR may be a risk factor for postoperative PPF.

Magnetic Resonance Classification System of Cervical Intervertebral Disk Degeneration: Its Validity and Meaning.

STUDY DESIGN: Retrospective analysis of kinetic magnetic resonance images (kMRIs). OBJECTIVE: (1) To analyze the changes seen on MRI related to disk degeneration and to develop a new grading system for cervical disk degeneration. (2) To evaluate the reliability and validity of the grading system. SUMMARY OF BACKGROUND DATA: Few have studied the relationship between changes seen on MRI with cervical disk degeneration and the chronological order of disk degeneration. A few grading systems for cervical disk degeneration have been reported; however, there have been problems related to subjectivity and lack of a clear, reliable algorithm. METHODS: A total of 300 cervical intervertebral disks were graded for nucleus color, structure, disk bulge, and disk height. On the basis of the analysis, a new grading system consisting of 4 grades (grade 0-III) and algorithm were developed. Intraobserver and interobserver reliabilities were assessed. A total of 2802 intervertebral disks were then evaluated using the grading system to correlate disk degeneration grades with patient age and function and to evaluate the validity of the new system. RESULTS: On the basis of cross-table analysis, disk degeneration presents in the following order: (1) decrease and/or change of nucleus intensity; (2) loss of distinction between nucleus and annulus; (3) positive disk bulge; and (4) disk height decrease. The κ-coefficients for intraobserver and interobserver agreements were 0.96 and 0.90, respectively. Severe disk degeneration is most common at C5/C6 followed by C6/C7 and C4/C5, and total disk degeneration grade is correlated with age (R=0.467). There was a decrease of angular motion in grades I-III and an increase in translational motion and decrease of space available for the cord in grades II-III. CONCLUSIONS: We developed a new classification system of cervical disk degeneration based on analysis of the changes seen on MRI. Reliability tests indicated high reproducibility of this system, and further analysis confirmed its validity and clinical significance.

Dynamic Evaluation of the Cervical Spine and the Spinal Cord of Symptomatic Patients Using a Kinetic Magnetic Resonance Imaging Technique.

PURPOSE: The purpose of this study was to examine the movement of the spinal cord and its relationship to the spinal canal in patients with mild spondylosis using kinetic magnetic resonance imaging (kMRI). METHODS: Weight-bearing, multiposition kMRI was performed on symptomatic patients through a full range of flexion-extension. A total of 52 study patients were selected based on the C2-C7 Cobb angle of sagittal alignment: lordotic (from 30 to 45 degrees). We evaluated dynamic changes in different parameters from flexion-extension: spinal canal diameter (CD), spinal cord diameter (SCD), space available for the cord, anterior space available for the cord (ASAC), posterior space available for the cord (PSAC), average distance between the anterior canal and the cord (d-value), and global angle for the spinal canal and cord. RESULTS: The CD tended to decrease from flexion to extension from C3/C4 to C6/C7, however, there were no significant differences at the proximal and distal levels, C2/C3 and C7/T1. There were no significant differences of SCD between different postures. The SCD tended to decrease from C2/C3 to C7/T1. The ASAC followed the same pattern as CD-values. The ASAC was narrowest at C4/C5 and C5/C6. The PSAC tended to increase from C2/C3 to C7/T1. The spinal cord shifted anteriorly with extension and posteriorly with flexion. In addition, the spinal cord maintained its curve with the movement. CONCLUSIONS: The kinematics of spinal cord motion may be associated with the pathogenesis of cervical spondylotic myelopathy. However, the spinal cord maintains its curve with position changes. Consequently, different motions of the cervical spine may affect spinal cord migration and cause changes in ASAC and PSAC.

A comparison of commercially available demineralized bone matrices with and without human mesenchymal stem cells in a rodent spinal fusion model.

OBJECTIVE The efficacy of some demineralized bone matrix (DBM) substances has been demonstrated in the spinal fusion of rats; however, no previous comparative study has reported the efficacy of DBM with human mesenchymal stem cells (hMSCs). There is an added cost to the products with stem cells, which should be justified by improved osteogenic potential. The purpose of this study is to prospectively compare the fusion rates of 3 different commercially available DBM substances, both with and without hMSCs. METHODS Posterolateral fusion was performed in 32 mature athymic nude rats. Three groups of 8 rats were implanted with 1 of 3 DBMs: Trinity Evolution (DBM with stem cells), Grafton (DBM without stem cells), or DBX (DBM without stem cells). A fourth group with no implanted material was used as a control group. Radiographs were obtained at 2, 4, and 8 weeks. The rats were euthanized at 8 weeks. Overall fusion was determined by manual palpation and micro-CT. RESULTS The fusion rates at 8 weeks on the radiographs for Trinity Evolution, Grafton, and DBX were 8 of 8 rats, 3 of 8 rats, and 5 of 8 rats, respectively. A significant difference was found between Trinity Evolution and Grafton (p = 0.01). The overall fusion rates as determined by micro-CT and manual palpation for Trinity Evolution, Grafton, and DBX were 4 of 8 rats, 3 of 8 rats, and 3 of 8 rats, respectively. The Trinity Evolution substance had the highest overall fusion rate, however no significant difference was found between groups. CONCLUSIONS The efficacies of these DBM substances are demonstrated; however, the advantage of DBM with hMSCs could not be found in terms of posterolateral fusion. When evaluating spinal fusion using DBM substances, CT analysis is necessary in order to not overestimate fusion.

The Compensatory Relationship of Upper and Subaxial Cervical Motion in the Presence of Cervical Spondylosis.

STUDY DESIGN: This study was an in vivo kinematic magnetic resonance imaging analysis of cervical spinal motion in human subjects. OBJECTIVE: The objective of the study was to identify associations between disk degeneration in the subaxial cervical spine and upper cervical spinal motion in patients with general age-related cervical spondylosis. SUMMARY OF BACKGROUND DATA: The kinematic relationship between the occipital-atlantoaxial complex and subaxial cervical spine in patients with cervical spondylosis and decreased cervical motion is not well understood. METHODS: A total of 446 symptomatic patients who had neck pain with and without neurogenic symptoms were included in this study. Kinematic magnetic resonance imaging was performed with dynamic motion of the cervical spine in upright, weight-bearing neutral, flexion, and extension positions. Intervertebral disk degeneration for each segment from C2-3 to C7-T1 and sagittal angular motion between flexion and extension for each segment from Oc-C1 to C7-T1 was evaluated. Depending on the amount of sagittal subaxial angular motion, the patients were classified into 3 groups by sagittal angular motion using cutoff points based on tertile (<36-degree group: 149 cases; 36-47-degree group: 148 cases; and >47-degree group: 149 cases). RESULTS: A significant correlation was found between subaxial angular motion and intervertebral disk degeneration, indicating that the subaxial motion decreases according to the degree of disk degeneration. Mean angular motion of the occipital-atlantoaxial complex, especially of Oc-C1, was significantly higher in the <36-degree and 36-47-degree group than in the >47-degree group, whereas no significant difference was found at C1-C2. CONCLUSIONS: Our study demonstrates that decreased subaxial cervical spinal motion is associated with intervertebral disk degeneration in a symptomatic population. This decrease in mobility at the subaxial cervical spine is compensated for by an increase in angular mobility of the upper cervical spine at the occipital-atlantoaxial complex, especially at Oc-C1.

When Is It Safe to Return to Driving After Spinal Surgery?

Study Design Prospective study. Objective Surgeons' recommendations for a safe return to driving following cervical and lumbar surgery vary and are based on empirical data. Driver reaction time (DRT) is an objective measure of the ability to drive safely. There are limited data about the effect of cervical and lumbar surgery on DRT. The purpose of our study was to use the DRT to determine when the patients undergoing a spinal surgery may safely return to driving. Methods We tested 37 patients' DRT using computer software. Twenty-three patients (mean 50.5 ± 17.7 years) received lumbar surgery, and 14 patients had cervical surgery (mean 56.7 ± 10.9 years). Patients were compared with 14 healthy male controls (mean 32 ± 5.19 years). The patients having cervical surgery were subdivided into the anterior versus posterior approach and myelopathic versus nonmyelopathic groups. Patients having lumbar spinal surgery were subdivided by decompression versus fusion with or without decompression and single-level versus multilevel surgery. The patients were tested preoperatively and at 2 to 3, 6, and 12 weeks following the surgery. The use of opioids was noted. Results Overall, the patients having cervical and lumbar surgery showed no significant differences between pre- and postoperative DRT (cervical p = 0.49, lumbar p = 0.196). Only the patients having single-level procedures had a significant improvement from a preoperative DRT of 0.951 seconds (standard deviation 0.255) to 0.794 seconds (standard deviation 0.152) at 2 to 3 weeks (p = 0.012). None of the other subgroups had a difference in the DRT. Conclusions Based on these findings, it may be acceptable to allow patients having a single-level lumbar fusion who are not taking opioids to return to driving as early as 2 weeks following the spinal surgery.

Trends and Demographics in Anterior Cruciate Ligament Reconstruction in the United States.

The purpose of this study was to identify the trends and demographics of patients undergoing arthroscopic anterior cruciate ligament (ACL) reconstruction in the United States. Patients who underwent arthroscopic ACL reconstruction between 2004 and 2009 were identified by searching Current Procedural Terminology codes in the PearlDiver Patient Record Database (PearlDiver Technologies, Fort Wayne, IN). The year of procedure, age, gender, and region of the United States were recorded for each patient. Associated meniscal procedures and the absence or presence of a femoral nerve block were also recorded. The incidence of ACL reconstruction significantly increased over the study period, from 40.9 cases per 10,000 patients in 2004 to 47.8 in 2009 (p < 0.001). Of these cases, 92.8% were associated with either meniscectomy or meniscal repair. ACL reconstruction was performed most commonly in patients aged 10 to 29 years (p < 0.001). A significant male predominance was observed with an incidence ratio of male-to-female of 2.03 (p < 0.001). The frequency of females undergoing ACL reconstruction as a proportion of the total number of annual cases increased from 2,295 in 2004 to 3,476 in 2009 (p = 0.0031). A significant increase in the annual proportion of ACL reconstruction performed under femoral nerve block was also observed, from 2.0% in 2004 to 8.3% in 2009 (p < 0.001). The greatest incidence of ACL reconstruction occurred in the Western region of the United States. An increase in the rate of arthroscopic ACL reconstruction was observed between 2004 and 2009 and 92.8% of the ACL reconstructions were associated with a meniscal procedure. The majority of cases were performed in patients aged 10 to 29 years, with a male predominance. Increases were observed in the number of female cases and proportion performed under a femoral nerve block. The Western region of the United States was found to have a higher incidence of ACL reconstruction.

Trends in the surgical treatment of lumbar spine disease in the United States.

BACKGROUND CONTEXT: There is a lack of agreement among spine surgeons as to the best surgical treatment modality for many degenerative lumbar diseases. Although there are many studies examining trends in spinal surgery, specific studies reporting the variations in surgical treatment in the United States for these diseases are lacking. PURPOSE: The aim of this study was to analyze trends in lumbar spinal fusion methods for common lumbar pathologies in the United States. STUDY DESIGN/SETTING: National insurance database review: 2004-2009. PATIENT SAMPLE: Data is taken from United Healthcare and represents more than 25 million patients. OUTCOME MEASURES: No outcomes were measured in this study. METHODS: Using a private insurance database, we identified patients who underwent one of five types of instrumented single-level lumbar spinal fusion for the 10 most common primary diagnoses. Surgery rates were reviewed from 2004 to 2009 and were stratified according to patient age, patient gender, and region in the United States. Poisson regression analysis was performed to determine regional and demographic differences in treatment modality. The authors received no funds in support of this work. RESULTS: A total of 23,986 patients met our search criteria. Of the five fusion types, posterior lumbar interbody fusion (PLIF) with posterolateral fusion (PLF) was the most common (45%), followed by PLF (19%), anterior lumbar interbody fusion (ALIF, 16%), PLIF (10%), and ALIF with PLF (9%). There was a significant increase in PLIF with PLF (p<.0001), PLIF (p<.0001), PLF (p=.012), ALIF (p<.0001), and ALIF with PLF (p<.0001) from 2004 to 2009. After controlling for gender, there were significant differences between regions for all fusion types (p<.0001). The likelihood of a posterior fusion increased with age. Anterior fusions were more common in the 30- to 49-year-old age range than in patents older than 50. For patients in age groups older than 30, there was an increased number who underwent a circumferential fusion or an ALIF (p<.022). Fusion types were significantly different between genders (p<.026). Both genders had an overall increase in the number of fusions (p<.001) over the time period studied. CONCLUSIONS: There are large differences in the United States for surgical treatment methods for lumbar spine pathology. These differences are likely multifactorial, with both patient and surgeon traits playing a role. Illustrating these differences will hopefully lead to outcomes research to determine the indications, efficacy, and appropriateness of these surgical methods, an important step on the path toward standardization of care.

Effect of disc degeneration on lumbar segmental mobility analyzed by kinetic magnetic resonance imaging.

STUDY DESIGN: Retrospective radiographical study. OBJECTIVE: To define the relationship between the grade of disc degeneration and the motion of the lumbar spine by using kinetic magnetic resonance imaging. SUMMARY OF BACKGROUND DATA: Disc degeneration is common after middle age. Lumbar instability has generally been recognized as a potential risk factor of low back pain. However, correlations between the grade of disc degeneration and the motion of the lumbar spine need more investigation. METHODS: Kinetic magnetic resonance imaging was performed in 162 patients with symptomatic low back pain without prior history of surgery. The lumbar intervertebral discs were graded by spine surgeons according to the degenerative grading system (grades I-V). Translational motion and angular variation were measured at each segment from L1-L2 through L5-S1. The relationship between the degree of lumbar disc degeneration and extent of lumbar spine mobility was analyzed. RESULTS: The translational motion in discs with grade I through IV increased gradually, but decreased with grade V. Compared with other less degenerative grades, grade V discs had significantly decreased total intervertebral translational motion (P < 0.05). The angular variation in discs with grade I through IV was fairly constant, but decreased with grade V. Compared with other degenerative grades (I-IV), grade V discs had significantly decreased total intervertebral translational motion (P < 0.05). For less degenerative grades I and II discs, the L2-L3 and L3-L4 segmental units contributed the majority of total angular mobility of the spine. However, for the severely degenerated segments, grade V discs, the contributions of the L2-L3 and L3-L4 significantly decreased (P < 0.01). CONCLUSION: As disc degeneration developed from the normal to an increasingly severe stage, the motion of lumbar spine progressed from the normal stage to an unstable phase with higher mobility and finally to an ankylosed stage where stability was increased. LEVEL OF EVIDENCE: 3.

Secreted phosphoprotein 24 kD inhibits nerve root inflammation induced by bone morphogenetic protein-2.

BACKGROUND CONTEXT: Bone morphogenetic protein-2 (BMP-2) has been used to successfully promote spine fusion, but side-effects including nerve inflammation have been observed. PURPOSE: To investigate the direct neurotoxic effects of BMP-2 and test the hypotheses that the use of BMP binding proteins, such as secreted phosphoprotein 24 kD (Spp24), can reduce or eliminate these effects. STUDY DESIGN: In vitro experiments and in vivo analysis in a rodent model. METHODS: In vitro, dorsal root ganglion cells were cultured in the presence of BMP-2 with and without Spp24 and calcitonin gene-related peptide and Substance P, markers of neuroinflammation, were measured by immunohistochemistry. In vivo, rats underwent a left-sided laminotomy at L5 to expose the S1 nerve root and were randomized into four different groups according to the intervention at the laminotomy site: collagen sponge only (no BMP-2 or Spp24), BMP-2 in a collagen sponge only, BMP-2 in a collagen sponge+an empty collagen sponge to act as a barrier, and BMP-2 in a collagen sponge+Spp24 in a collagen sponge to act as a barrier. Functional evaluation was done using the Basso, Beattie, and Bresnahan scale and immunohistochemical analyses were performed using calcitonin gene-related peptide and Substance P staining. RESULTS: The neuroinflammatory effects of BMP-2 in vitro were ameliorated by the addition of Spp24. Similarly, in vivo, Spp24 reduced the expression of markers on neuroinflammation in animals treated with BMP-2 and also improved the function after BMP-2 administration. CONCLUSIONS: These results confirm that BMP binding proteins have great potential as adjuvant therapies to limit BMP-2 related side-effects in spine surgery.

Association of genetic variations in HLA-B region with hypersensitivity to abacavir in some, but not all, populations.

Abacavir is an effective antiretroviral drug used to treat HIV-1 infection. Approximately 5% of patients treated with abacavir develop a hypersensitivity reaction that requires discontinuation of the drug. In an initial pharmacogenetic study conducted in a predominantly White male population, multiple markers in the human leukocyte antigen (HLA)-B chromosomal region were associated with hypersensitivity to abacavir. The HLA-B*5701 association has now been confirmed in White males in a subsequent, larger study (n=293, p=4.7 x 10(-18)) and is also observed in White females (n=56, p=6.8 x 10(-6)) and Hispanics (n=104, p=2.1 x 10(-4)). HLA-B*5701 was not associated with hypersensitivity in Blacks (n=78, p=0.27). HLA-B*5701 alone lacks sufficient predictive value to identify patients at risk for hypersensitivity to abacavir across diverse patient populations. Efforts are ongoing to identify markers with sufficient sensitivity and specificity to be clinically useful. Even after a marker set is identified, appropriate clinical identification and management of hypersensitivity to abacavir must remain the cornerstone of clinical practice.

Supplementation of grazing dairy cows with rumen-protected tuna oil enriches milk fat with n-3 fatty acids without affecting milk production or sensory characteristics.

The present study was conducted to determine the pattern of incorporation of dietary EPA and docosahexaenoic acid (DHA) into milk, and to evaluate consequent changes in milk fat composition and sensory characteristics. Fourteen multiparous cows in early lactation were divided into two groups and were offered supplements for 10 d. While individual stalls after each morning milking, one group was offered a mixture of rumen-protected tuna oil (RPTO)-soyabean supplement (2 kg; 30:70, w/w; +RPTO) and the second group was offered the basal ration without RPTO (-RPTO). Both groups grazed together on a spring pasture after supplementation. Feeding supplemental RPTO increased the concentrations of EPA and DHA in milk fat from undetectable levels in -RPTO cows to 6.9 and 10.1 g/kg milk fat respectively. Total n-3 PUFA concentration in milk fat was increased three- to fourfold by tuna-oil supplementation (8.4 to 32.0 g/kg milk fat). There were no significant effects on milk production (35.4 v. 33.9 l/d), milk protein (28.2 v. 30.1 g/kg) or milk fat (36.2 v. 40.4 g/kg for -RPTO and +RPTO respectively). The concentration of total saturated fatty acids in milk fat was significantly reduced (568 v. 520 g/kg total fatty acids) and there was a 17 % reduction in the atherosclerotic index of milk after tuna-oil supplementation. Untrained consumer panellists (n 61) rated milk from both groups of cows similarly for taste and smell. We conclude that it is possible to enrich milk with n-3 PUFA without deleterious effects on yield, milk composition or sensory characteristics.