Center In Alexandria Research Articles

Ocular response analyzer and posterior segment optical coherence tomography findings in refractive surgery candidates

Aim The aim of the study was to report on the ocular response analyzer and posterior segment optical coherence tomography findings in refractive surgery candidates. Patients and methods The study was conducted on 100 eyes of 50 (37 females) patients seeking refractive surgery at a private eye center in Alexandria, Egypt. Following detailed history taking, all study participants were subjected to a thorough ophthalmic examination including assessment of uncorrected and best-corrected visual acuity, manifest and cycloplegic refraction, slit-lamp examination, measurement of intraocular pressure (IOP) using Goldmann applanation tonometry, and fundus examination using a high plus auxiliary lens. Optical coherence tomography and corneal biomechanical properties were then studied using the Reichert ocular response analyzer. Results The mean±SD age of the study patients was 25.27±4.9 years and of contact lens wear (24% of study patients) was 2.5±0.9 years. The mean±SD of the manifest refractive error was −5.6±5.2 D sphere and −1.6±1.2 D cylinder and of the best-corrected visual acuity was 0.9±0.2. The mean±SD of the IOPg, IOPcc, corneal hysteresis and cornea resistance factor were 14.9±3.8, 16.5±3.4, 9.3±1.9, and 9.4±2 mmHg, of the Peripapillary Retinal Nerve Fibre Layer (pRNFL) thickness were 68.9±20.5 μ nasal, 113.3±20.7 μ superior, 77.7±16 μ temporal, and 119.3±21.5 μ inferior and of the central macula thickness was 270.8±22.9 μ. Conclusions The corneal biomechanical properties and the macular nerve fiber layer thickness are not correlated with the refractive error of the eye, whereas the peripapillary nerve fiber layer thickness correlates with the refractive error and the visual acuity. Screening of the corneal biomechanical properties and the nerve fiber layers is recommended for refractive surgery candidates.

P-572 Hormonal Monitoring and Progesterone Adjustment in Frozen Embryo Transfer Cycles

Abstract Study question We investigated the effect of monitoring and follow-up of serum progesterone, estradiol & luteinizing hormone levels and progesterone supplement adjustments on pregnancy outcomes for FET in programmed HRT cycles. Summary answer Monitoring and follow-up of different hormones in patient’s serum in programmed frozen embryo transfer cycles didn’t have an impact on overall pregnancy rate. What is known already Frozen Embryo transfer treatment rapidly expanded in recent years. FET can effectively prevent IVF associated complications, such as ovarian hyperstimulation syndrome and multiple pregnancy. In addition, FET serves as a safe & cost-effective way to increase cumulative pregnancy rate. Though progesterone levels on the day of transfer have not yet been studied extensively in humans, tailoring the time of transferring a frozen embryo based on serial P4 values rather than cycle day number alone results in higher pregnancy rates.The value of measuring the serum E2 levels on the day of embryo transfer as an indicator for clinical pregnancy is still doubtful. Study design, size, duration Six Hundred FETs were performed in a randomized prospective manner in an infertility center in Alexandria starting from 2019 till 2021.These were further subdivided based on computer randomization into Group I (Non-intervention) including300 patients with only ultrasound monitoring & Group II (intervention) including 300 patients with monitoring of serum level of progesterone, estrogen & luteinizing hormone as well as progesterone supplement adjustments. Participants/materials, setting, methods Group I (Non-intervention) including300 patients with only ultrasound monitoring & Group II (intervention) including 300 patients with monitoring of serum level of progesterone, estrogen & luteinizing hormone as well as progesterone supplement adjustments which are further subdivided into three groups depending on progesterone level in patient’s serum early in the morning prior to embryo transfer. Group II A: P4 levels < 5ng/dl, Group II B: P4 levels 5-10ng/dl, Group II C: P4 levels >10ng Main results and the role of chance Live birth and overall pregnancy rate showed no significant difference among group monitored with ultrasound only compared to the hormonal monitored group. However, on the day of embryo transfer, serum P4 > 11.83 ng/ml represented a cut-off value above which there is marked increase in OPR/LBR and a sensitivity of 53.7% & specificity of 51.2% in predicting pregnancy. Also, serum E2 value more than 292 pg/ml at day 18 demonstrated an increase in OPR/LBR.In our study, the cut off value of LH level less than of 10.8 IU/L at day13 had a sensitivity of 58.3% & specificity of 50.4% in predicting pregnancy. Regarding pregnancy outcome, monitoring of LH levels didn’t generate useful data with no added prognostic value.Conclusion: Monitoring and follow-up of different hormones in patient’s serum in programmed frozen embryo transfer cycles didn’t have an impact on live birth, overall pregnancy & abortion rate when compared to ultrasound only in non-intervention group. Limitations, reasons for caution Patients in non-intervention group didn’t have a hormonal pre-transfer assessment so it’s not possible to determine if the progesterone levels are suboptimal or not when compared to intervention group. Also, we didn’t have a post transfer hormonal assessment in case group to determine whether the progesterone dose reached desired levels. Wider implications of the findings Kofinas et al. proposed in his study that in order to optimize pregnancy and rate, P4 levels in FET cycles should be sustained between 10 and 20 ng/ml. This was in accordance to our study where the cut off value of P4 on day of 11.83 ng/ml optimized pregnancy rates. Trial registration number NCT05189145

Pediatric Keratoconus in A Tertiary Eye Center in Alexandria: A Cross-sectional Study

ABSTRACT PURPOSE To describe the clinical presentation, risk factors, and treatment choices documented in a pediatric keratoconus population treated at a tertiary referral center in Alexandria, Egypt. METHODS : A cross-sectional study of 80 patients with keratoconus aged 18 years or younger referred to the cornea clinic at the Alexandria University Main Hospital between July 2018 and October 2019 was included. Patients’ history, initial presentation, best spectacle corrected visual acuity (BSCVA), clinical signs, topographic data, and treatment were recorded. RESULTS Thirty patients were younger than 14 years and 50 were 14 years or older. Elements of the initial presentation included decreased vision in 26 patients, itching in 20 patients, both visual impairment and itching in 16 patients, accidental discovery during vision screening at school in 15 patients, and hydrops in three patients. All patients had bilateral keratoconus, except for four patients who had previously been treated by keratoplasty (n = 156 eyes). The mean logMAR BSCVA was 0.79 ± 0.63. The mean of the average keratometry (AveK), maximum keratometry (Kmax), central corneal thickness (CCT) and thinnest pachymetry reading were 51.16 ± 7.31 D, 59.18 ± 10.38 D, 458.44 ± 55.87 µ 440.08 ± 60.18 µ, respectively. 57 eyes (36%) had stage 1 disease, 43 eyes (28%) had stage 2 disease, 17 eyes (11%) had stage 3 disease and 39 eyes (25%) had stage 4 disease, respectively. No statistically significant differences in the LogMAR BSCVA, keratometry values, CCT, thinnest pachymetry reading, and the Amsler-Krumeich (AK) staging existed between the two age groups or between boys and girls. Crosslinking was indicated in 69 eyes (44%), while keratoplasty was the only viable solution for 39 eyes (25%), with three patients requiring keratoplasty in both eyes. CONCLUSION Keratoconus in children can result in severe loss of vision. Keratoconus screening programs in elementary schools should be considered in populations with a high incidence of keratoconus for early detection and adequate intervention.

Changes in macular thickness after trabeculectomy with or without adjunctive mitomycin C

Objective To assess macular thickness changes posttrabeculectomy with and without mitomycin C (MMC) and to find the association between these postoperative changes and intraocular pressure (IOP). Patients and methods This study included 40 eyes of 31 patients who underwent trabeculectomy. It was done at a private eye center in Alexandria from December 2017 to September 2018. Study patients were stratified into two groups (20 each): trabeculectomy with MMC and trabeculectomy without MMC. Results The mean (±SD) (IOP) reduced from 29.48 (±3.57) mmHg before trabeculectomy to 19.05 (±2.86) mmHg 1 week (P Conclusion Trabeculectomy may increase macular thickness in the early postoperative period. However, MMC has no effect despite its possible toxic effects on the retina.

Occurrence and biofilm forming ability of Pseudomonas aeruginosa in the water output of dental unit waterlines in a dental center in Alexandria, Egypt.

Dental unit waterlines (DUWLs) are notorious for being contaminated with different bacterial species including the opportunistic pathogen Pseudomonas aeruginosa which poses a risk to patients and professionals. This work aimed at studying the occurrence and biofilm-forming ability (BFA) of P. aeruginosa in the output of DUWLs in a dental center in Egypt. Water samples were collected from the outlets of the high-speed hand piece, the air/water syringe and the cup filler waterlines. Bacteriological analysis included heterotrophic plate count (HPC), isolation and identification of P. aeruginosa and determination of the antimicrobial susceptibility and the BFA of the isolates by tissue culture plate (TCP) method and tube method (TM). The average concentration of HPC bacteria in the output of the 3 DUWLs was 2.9×104 CFU/μL where 88.3% of the samples exceeded the Egyptian standards for drinking water (<50 CFU L). P. aeruginosa was isolated from nine cup filler samples (which had a water source different from the other waterlines). The isolates were sensitive to all tested antimicrobials. Of these nine isolates, 6, 5 and 4 were positive for BFA by TCP, modified TCP and TM, respectively. More stringent measures are required to ensure safer dental water; as the majority of studied samples exceeded the required HPC bacterial limit and P. aeruginosa isolates were detected. P. aeruginosa isolates from DUWLs may not be as resistant to antibiotics as what is reported in the literature about clinical isolates. Some P. aeruginosa isolates can colonize DUWLs despite their inability to form biofilms in experimental testing.

Microbiological monitoring of ultrapure dialysis fluid in a hemodialysis center in Alexandria, Egypt

Microbiological contamination of dialysate is an issue that attracted attention since the 1990s. This is partly due to the extensive use of sodium bicarbonate as a dialysate buffer, which helps mic...

Lilly spreads out in New York City

Eli Lilly & Co. cut the ribbon last week on immuno-oncology labs for 40 researchers at the Alexandria Center for Life Science, a two-tower life sciences research facility on the East River in Manhattan. Lilly, the anchor tenant at the Alexandria Center, arrived in 2010 and added a second bank of labs in 2015 focused on immune-system oncology. Jan M. Lundberg, president of Lilly Research Laboratories, said the newest labs are intended to make the company’s research more “efficient and competitive” and to locate it “in an environment in which, just outside our center, are tremendous opportunities to collaborate with leading clinical centers.” The center’s neighbors include Memorial Sloan Kettering Cancer Center and Weill Cornell Medicine.

Laser-assisted in-situ keratomileusis with iris registration against manual limbal markings for the correction of myopic astigmatism

Purpose The aim of this study was to compare the refractive outcomes and visual acuity of laser-assisted in-situ keratomileusis (LASIK) with static preablation iris registration (IR) and LASIK with that of manual limbal markings (LM) in the management of myopic astigmatism. Setting The study was carried out at El-Safwa Laser Vision Center in Alexandria, Egypt. Patients and methods This prospective randomized clinical study was conducted on 40 eyes that were divided into two groups. Group A (IR group) was treated with LASIK procedure with preablation static IR (software of WaveLight EX500 Excimer laser) in conjunction with the Topolyzer Vario to automatically detect and adjust cyclotorsional misalignment. Group B (LM group) was treated with LASIK with the same machine without using the IR software and instead using a corneal marking pen for LM for manual cyclotorsional misalignment adjustments. Refraction and visual acuity data were compared between groups at the first, third, and sixth postoperative months. Vector analysis was performed by the Alpins method using data from the third postoperative month. Results The mean preoperative spherical error was −2.75±1.84 and −3.05±2.67 D in the IR group and the LM group, respectively (P=0.946). The mean preoperative cylindrical error was −2.65±0.81 and −2.31±0.41 D in the IR group and the LM group, respectively (P=0.170). At the sixth postoperative month, the mean spherical error of the IR group was −0.06±0.29 D, whereas that of the LM group was −0.08±0.24 D (P=0.822). The mean cylindrical error of the IR group was −0.43±0.23 D, whereas that of the LM group was −0.38±0.21 D (P=0.353). There was no statistically significant difference between the two groups regarding manifest refraction, best corrected visual acuity, uncorrected visual acuity, and safety index at all postoperative time points. There was no statistically significant difference between the two groups regarding target-induced astigmatism, difference vector, magnitude of error, angle of error, and predictability at 3 months postoperatively. However, the surgically induced astigmatism and efficacy were statistically significantly higher in the IR group at 3 months postoperatively. Conclusion Using the EX500 Excimer laser system, LASIK with IR software is as safe and predictable as LASIK with LM in the treatment of myopic astigmatism.

New York City spends on life sciences

New York City will spend $500 million in an effort to create 16,000 jobs in the life sciences and related fields. Speaking at the Alexandria Center, a research campus that opened in 2011 in Manhattan, Mayor Bill de Blasio said the plan centers on a $100 million facility in the neighborhood or across the East River in Long Island City, Queens. It includes $50 million to expand operations at nonprofit research facilities in the city and $10 million to expand business incubators. The city is also committing $300 million in tax incentives in the hope of attracting investment in commercial lab space for life science businesses.

GnRh Agonist Treatment Improves Implantation and Pregnancy Rates of Frozen-Thawed Embryos Transfer.

To study the effect of GnRh agonist administration prior to estrogen-progesterone preparation of the endometrium on the implantation rate in frozen-thawed embryo transfer (FET) cycles in infertile patients treated with IVF/ICSI. Prospective controlled study. Private center in Alexandria, Egypt. Patients undergoing frozen-thawed embryo transfer FET. Patients were divided into two groups, A and B. Group A patients consisted of 110 patients (110 cycles) who received daily subcutaneous injections of 0.1mg of the GnRh agonist triptorelin starting from the mid-luteal phase of the cycle preceding the actual FET cycle. The dose was reduced to 0.05mg from the second day of the cycle when daily oral estradiol valerate 6mg was also started. Daily vaginal supplementation of micronized progesterone 400mg b.d. was started after 12days when the GnRh agonist was also stopped. Frozen-thawed embryos were transferred on day+1 of their chronological age and when the endometrium reached 12mm in thickness. Group B consisted of 100 patients (100 cycles) who started daily estradiol valerate 6mg administration from the second day of the FET cycle and followed the same regimen but without prior treatment with triptorelin. Implantation and pregnancy rates were compared among the two groups. There was a significant increase in implantation rate in the GnRh agonist group (group A) compared to the estrogen and progesterone only group (group B) (44.1 vs. 21.1%; P=0.002*). The pregnancy rate was also significantly higher in group A compared to group B (65.5 vs. 42%, P=0.013*). GnRh agonist administration during endometrial preparation for FET increases the implantation and pregnancy rates.

New York City gets biotech incubator

Alexandria Real Estate Equities is building what it calls a first-of-its-kind biotech incubator in New York City. Alexandria LaunchLabs will open in 2017 with more than 1,400 m2 of lab and office space at the Alexandria Center for Life Science on Manhattan’s East Side. At the same time, Alexandria is forming a seed capital fund that will make up to $25 million available to companies that emerge from New York City’s academic labs. Tenants of LaunchLabs will have priority access to funds.

The 'Adapted ADAPTE': an approach to improve utilization of the ADAPTE guideline adaptation resource toolkit in the Alexandria Center for Evidence-Based Clinical Practice Guidelines.

The ADAPTE methodology for adaptation of guidelines has been used by many organizations to develop high-quality clinical practice guidelines. Although it is a valid alternative for de novo development of guidelines, it might demand more time and resources in some institutions. The present study demonstrates the proposed 'adapted ADAPTE' methodology to support more clarity, simplicity and practicality. It also aims at avoiding duplication within the process and reducing the resources and time allocated to the CPG adaptation projects. Clinical guidelines' adaptation in the Center for Evidence-Based Clinical Practice Guidelines at the Alexandria Faculty of Medicine and University Hospitals involves two stages: (1) cross-sectional or retrospective study to reveal the current practice and prescribing patterns concerning the selected health topic; (2) the 'adapted ADAPTE' methodology for CPGs adaptation that was based on the original ADAPTE Process. The 'adapted ADAPTE' included three modified tools, three new tools based on the original ADAPTE framework and alternatives for four ADAPTE steps to enhance utilization. The finalized adapted CPGs included nine high priority topics for paediatrics and two topics for emergency medicine. The ADAPTE methodology for guideline adaptation can be customized or 'adapted' to the local health care setting and resources. This proposal facilitates supports and improves the utilization and update of the ADAPTE process by CPG programmes or activities in health care organizations. This is of particular importance in health care systems in developing countries with limited resources in the Eastern Mediterranean region like Egypt.

Assessment of heavy metals by sediment quality guideline in surficial sediments of Abu Qir Bay southeastern mediterranean sea, Egypt

Abu Qir Bay is one of the Mediterranean coastal bays in Egypt. Its importance derives from its geographical location. It is considered the estuary for several huge drains, containing residues of agricultural and industrial in addition to its importance as a fishing center in Alexandria. The present study deals with the assessment of the quality of sediments using sediment quality guidelines (SQGs), developed by the National Oceanographic and Atmospheric Administration (NOAA) in the United States, to estimate possible adverse biological effects of sedimentary contaminants in Abu Qir Bay. The dataset comprised results from Abu Qir Bay sediment samples. Samples were analyzed for grain size, TOC and metals (Cd, Cr, Pb, Cu, Zn, and Fe). The NOAA guidelines indicate that Cd and Pb are the most likely contaminants to cause adverse biological effects in Abu Qir Bay.

103 Evaluation of the Immediate Role of Decompressive Craniectomy in the Treatment of Refractory ICP in Cases of Traumatic Brain Injury. Experience of a Tertiary Care Trauma Center in Alexandria, Egypt

103 Evaluation of the Immediate Role of Decompressive Craniectomy in the Treatment of Refractory ICP in Cases of Traumatic Brain Injury. Experience of a Tertiary Care Trauma Center in Alexandria, Egypt

Use of herbal medicines among pregnant women attending family health centers in Alexandria

Abstract Objective The aim of the study is to elucidate the use of herbal medicines in pregnant women and to explore patterns of herbal medication use including dietary supplements in pregnant women in Alexandria, Egypt. Methodology A cross sectional study of pregnant females was conducted in a family health center in Alexandria between March and June 2011 utilizing a sample of 300 pregnant women (100 pregnant women in each trimester). A specially designed self administered questionnaire was used to collect the data. Results The mean age of studied pregnant women was 26.9 ± 4.9 years. Only 27.3% of the studied pregnant women reported the use of herbal medicines during pregnancy while 89% reported the use of dietary supplements. The majority of pregnant women resorted to (family/friends) as primary source of information of herbal medicines (42.7% and 28%, respectively), while the majority of women using dietary supplements resorted to (physicians) as primary source of information (76%). 52.4% of the studied pregnant women reported that they use ginger during the 1st trimester of pregnancy while 51.6% reported that they use fenugreek during the 3rd trimester of pregnancy. More than half of the studied pregnant women (64.6%) reported the efficacy of herbal medicines in relieving their complaints during pregnancy. Conclusion The use of herbal medicines during pregnancy in Alexandria was uncommon while the use of dietary supplements was very common. About three quarters of studied sample reported that the physician was the person to recommend dietary supplement usage while the physician was rarely cited as the person recommending herbal usage. The most common herbs used by pregnant women were aniseed, fenugreek, ginger, while the least used was peppermint. Ginger was found to be used by a significantly higher percentage of pregnant women in the first trimester; on the other hand, fenugreek was used by a significantly higher percentage of pregnant women in the third trimester. Recommendations Results of the following study suggest the following recommendations: General recommendations General health education for pregnant women about benefits and harms of herbal use during pregnancy in ante-natal care especially for herbs commonly used in Egypt. Specific recommendations A Care providers: Training of family physicians in the family health centers on the use of herbal medicines in pregnancy and possible effects on the fetus. B Pregnant women: Health education program directed toward pregnant women to increase their awareness about the effects of herbal medicines.

Contamination of irrigation systems of dental units with Cryptosporidium species in Alexandria, Egypt: a neglected disinfection pitfall.

PurposeTo investigate the contamination of the dental irrigation systems with Cryptosporidium species in Alexandria, Egypt.MethodsForty water samples from all 20 working dental irrigation machines in a dental center in Alexandria were included in the study. Water samples were taken from the handpieces of dental irrigation machines in all studied units. After filtration through a membrane filter, water sample residues were stained using modified Ziehl–Neelsen staining and examined microscopically for Cryptosporidium spp.ResultsCryptosporidium spp. was found as a contaminant in 27.5% of water samples taken from dental irrigation machines.ConclusionThis indicates a contamination by the public water supplies to which these dental irrigation machines are connected. This disinfection pitfall may pose an infection risk to those seeking dental care.

Incidence and patterns of injury-related mortality

Injuries, with their grave social and economic consequences, although preventable, are an important cause of death in individuals in their most productive earning years, especially in developing countries. This study aimed to determine the incidence and describe the patterns of injury-related mortality in Alexandria, Egypt, through 2000-2010, and to identify their association with some demographic characteristics. Data were collected from the information and decision support center in Alexandria, as case records, for the period 2000-2010. STATA 11 software was used. Time-series analyses (trends and seasonality) were performed for all injuries combined and separately. The association between demographic characteristics and injury-related mortalities was determined using zero-inflated Poisson regression. Injury-related mortalities comprised a total of 19 731 deaths between 2000 and 2010 (the incidence ranged between 38.3/100 000 and 51.1/100,000). Road traffic accident was the first leading cause. Almost 70% of injury-related deaths occurred in the age group 15 to <60 years. Men were more at risk than women for all types of injuries, except burns. Higher rates were calculated for poor and remote districts. Summer months showed the highest seasonal index for each type and all combined. Policy makers need to recognize injuries as a public health crisis, especially road traffic accidents, and need to design and implement urgent interventions for safety applicable to the Egyptian demography and distribution.

P1-65 Road traffic accidents in Alexandria, Egypt: trends of mortality (2000–2009)

IntroductionRoad traffic accidents (RTA) with their serious social and economic consequences, though preventable, comprise an important cause of death and disability in developing countries, where the problem is increasing rapidly...

Should fine‐needle aspiration cytology be the first choice diagnostic modality for assessment of all nonpalpable breast lesions? The experience of a breast cancer screening center in Alexandria, Egypt

Fine-needle aspiration cytology (FNAC) of breast masses has been replaced by ultrasound-guided core-needle biopsy (USG-CNB) in many countries. However, in Egypt, breast FNAC continues to play the major role in diagnosing breast masses. In this prospective study, we evaluated the efficacy of USG-FNACs performed at a breast cancer screening center by comparing the FNAC results with the corresponding definitive histological examination outcome. We also investigated the role that CNB can play as a complementary diagnostic tool for FNAC in selected cases. A total of 229 consecutive nonpalpable breast masses were included in this study. Each FNAC was placed into one of four categories: 3.5% nondiagnostic, 13.5% benign, 12.3% atypical/suspicious (indeterminate), and 70.7% malignant. The overall diagnostic accuracy was 98.9%, with a specificity and sensitivity of 99.3 and 96.7%, respectively. The overall positive predictive values and negative predictive values were 99.3 and 96.7%, respectively. Only 37 masses (16%) were converted to CNB, with the indeterminate cytology being the most common cause (54%) for this conversion. Two cases demonstrating the superior benefit of FNAC over CNB are illustrated. Although we started the study by reserving CNB as a first choice to assess microcalcifications without architectural distortion, we ended the study by deciding to perform combined FNAC and CNB for this type of lesions. In conclusion, aiming to maximize the preoperative diagnosis of cancer, it would be cost efficient and time saving to use FNAC as a first-line investigation to benefit from the wealth of cytological information yielded, followed by CNB in selected cases.

Automatic Processing of Multi-Array Long-Period Seismic Data

Summary Long-period seismic data from the three large arrays ALPA, LASA, and NORSAR are telemetered to the Seismic Array Analysis Center in Alexandria, Virginia, where they are processed in real time by employing a fast frequency-wavenumber (f-k) detection scheme. The processor incor- porates a novel f-k filtering technique which allows the separation of interfering signals and the extraction of small signals from noise. Surface wave magnitudes (Ms) are derived directly from the processor output. The Seismic Array Analysis Center (SAAC) in Alexandria, Virginia, receives the long-period seismic data transmitted continuously from the Large Aperture Seismic Array (LASA) in Montana and other large long-period arrays located in Alaska (ALPA) and Norway (NORSAR). As part of the evaluation of this network these data are processed to detect and measure Rayleigh waves associated with seismic events listed in the LASAISAAC Daily Event Summary. The choice of data processing methods was influenced by the fact that approxi- mately 100 events per day have to be processed in real time. Time domain beam- forming and plotting is a slow process which suffers from the disadvantage that the propagation azimuth and velocity must be assumed. Any disturbance visible on a particular beam may be associated with adjacent beams or with a side lobe. For these and other reasons, a frequency-wavenumber Cf-k) approach has been used for routine analysis of the LP data (Mack 1972). The heart of the processing scheme is the fast signal detection algorithm FKCOMB (Smart 1972), which makes used of frequency-wavenumber transforms. This refer- ence also describes the principles of thef-k analysis of transient waveforms. FKCOMB was originally used for the automatic processing of microbarograph array data (Smart & Flinn 1971). In this paper we merely summarize the method of analysis and outline how it is applied in the SAAC to detect Rayleigh waves and to obtain seismic surface wave magnitudes on a real-time basis. Frequency wavenumber analysis Frequency-wavenumber Cf-k) spectral estimation is a powerful technique for signal detection and waveform analysis of digitally recorded array data. The f-k spectrum of a given segment of array output is the squared modulus of the multi- dimensional Fourier transform of the data in time and space. Thef-k spatial represen- tation of a propagating wave is shown schematically in Fig. 1. Using discrete Fourier t Present address: Exploration Services Center, Mobd Oil Corporation, Dallas, Texas 75221.