scholarly journals A Simple Surgical Approach for the Management of Acquired Severe Lower Punctal Stenosis

2019 ◽  
Vol 2019 ◽  
pp. 1-5
Author(s):  
Sameh S. Mandour ◽  
Khaled E. Said-Ahmed ◽  
Hany A. Khairy ◽  
Moataz F. Elsawy ◽  
Marwa A. Zaky
Keyword(s):  
Nasolacrimal Duct ◽  
Ophthalmological Examination ◽  
Slit Lamp ◽  
University Hospitals ◽  
Silicone Tube ◽  
Significant Difference ◽  
Fluorescein Dye ◽  
The Difference ◽  
One Year ◽  
Punctal Stenosis

Purpose. Evaluation of using pigtail probe to detect and open severely stenosed lower lacrimal punctum followed by self-retaining bicanalicular intubation. Study design. A prospective nonrandomized clinical study. Methods. The study included 24 patients with severe lower punctal stenosis (grade 0 according to Kashkouli scale) attending at Menoufia University Hospitals. The upper punctum and canaliculus were patent. All patients were complaining of epiphora and had a thorough ophthalmological examination including dye disappearance test and slit-lamp examination. Pigtail probe was used from patent upper punctum to detect the lower stenosed punctum which was opened with a scalpel. Syringing of the lower lacrimal passages was done to confirm its patency, and self-retaining silicone bicanalicular stent was inserted. The silicone tube was left in place for 6 months before it was removed. Patients were then followed-up for 1 year after the surgery. Results. One year after surgery, epiphora was absent (grade 0) in 16 eyes (66.7%) and was present only occasionally (grade 1) in 4 eyes (16.7%). The difference from preoperative epiphora was statistically significant. One year after surgery, fluorescein dye disappearance time was grade 1 (<3 minutes) in 20 cases (83.3%), and grade 2 (3–5 minutes) in 4 cases (16.7%). There was a statistically significant difference compared with preoperative results. Conclusion. Using the pigtail probe is effective in treatment of severe punctal stenosis. Maintaining the punctal opening and prevention of restenosis can be achieved by using self-retaining bicanalicular stent after confirmation of nasolacrimal duct patency. This trial is registered with NCT03731143.

scholarly journals The Effect of Multiple Sclerosis on Nerve Fiber Layer of the Retina

QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
A A A Mohamed ◽  
A M Saad ◽  
T H Mohamed ◽  
Y A Elzanklony
Keyword(s):  
Multiple Sclerosis ◽  
Visual Acuity ◽  
Optic Neuritis ◽  
Control Group ◽  
Ophthalmological Examination ◽  
Slit Lamp ◽  
University Hospitals ◽  
Rnfl Thickness ◽  
Study Results ◽  
Significant Difference

Abstract Background Multiple Sclerosis is a chronic idiopathic inflammatory demyelinating disease involving Central Nervous System white matter with relapsing-remitting nature. Optic neuritis is a common initial manifestation. Multiple Sclerosis is characterized by dual pathological process of inflammation and neurodegeneration. It causes prominent retinal neural ganglion cell layer loss in addition to related axonal loss which can be identified by thinning of RNFL seen in OCT. Patients and Methods This case control study was carried out at Ain Shams University Hospitals in MS clinic of neurology department and Ophthalmology outpatient clinics. with a total of 100 eyes, from 50 subjects, Group A (10 patients, 20 eyes): normal persons with normal eyes as a Control group and 40 patients (80 eyes) having multiple sclerosis who satisfied the inclusion and exclusion criteria subdivided into 2 groups,(group B) 20 patients having previous attack of Optic Neuritis & (group C) 20 patients not having previous Optic Neuritis. Informed consents were obtained from all subjects and ethics approval were obtained from Ain Shams University Hospitals Ethical Commitee: A complete ophthalmic history and ophthalmological examination were done for each subject. Visual acuity assessment using Auto Refractometer, refraction, uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) assessment using Snellen chart and also calculated in Logarithm of Minimum Angle of Resolution (LogMAR).Pupil reaction. Color vision assessment. Anterior segment detailed Slit Lamp examination. Posterior segment examination (ONH examination) using Slit lamp biomicroscopy, Volk +90 Diopter lens. Intraocular tension measured by Goldmann applanation tonometry. OCT to evaluate RNF layer thickness and c/d ratio. Results Our study results demonstrated that: VA & BCVA were statistically significant lower in MS group than the control group (P = 0.011, 0.006 respectively). Total, superior, inferior and temporal RNFL thickness were statistically significant lower in MS group than the control group(P = 0.003, 0.004, 0.028, 0.018 respectively), while there was no statistically significant difference between the two studied groups regarding nasal RNFL thickness. Total, all the four quadrants superior, inferior, temporal and nasal RNFL thickness were statistically significant lower in MS group with previous attack of ON compared with the MS group not having previous ON (P = 0.000, 0.000, 0.004, 0.004, 0.024 respectively). Conclusion This study also suggests a great role of ocular imaging techniques such as OCT as an effective noninvasive, high-resolution, non contact tool in mapping of subclinical retinal changes (GCIP layer) in MS patients. It may also serve as a diagnostic adjunct for monitoring disease activity and responses to neuroprotective drugs.

scholarly journals Comparison of the efficacies of 1.0mm and 1.5mm silicone tubes for the treatment of nasolacrimal duct obstruction

2021 ◽  
Author(s):  
Jutaro Nakamura ◽  
Tomoyuki Kamao ◽  
Arisa Mitani ◽  
Nobuhisa Mizuki ◽  
Atsushi Shiraishi
Keyword(s):  
Recurrence Rate ◽  
Patency Rate ◽  
Large Diameter ◽  
Nasolacrimal Duct ◽  
Nasolacrimal Duct Obstruction ◽  
Silicone Tube ◽  
Duct Obstruction ◽  
Tube Removal ◽  
The Difference ◽  
One Year

Abstract Purpose: We compared the difference in postoperative patency rates due to the differences in the diameter of silicone tubes used for bicanalicular intubation for the treatment of nasolacrimal duct obstruction (NLDO). Methods: Patients diagnosed with NLDO at Ehime University Hospital between August 2013 and November 2020 who underwent endoscopic-assisted nasolacrimal duct intubation (ENDI) were included in the study. The patients involved were 130 cases and 157 sides (age 72.6 ± 11.3 years) who were eligible for follow-up for more than six months after the removal of the lacrimal silicone tube. The postoperative recurrence rate was compared retrospectively based on the difference in tube caliber. The patients were divided into two groups: those intubated with a 1.5-mm large diameter tube (Group LD) and those with a 1.0-mm normal diameter tube (Group ND). The survival rates of the two groups at one year after tube removal were compared by Kaplan-Meier's curve and Restricted mean survival time (RMST) method with τ = 365 days. Results: There were no significant differences in age, gender, or observation period after tube removal between the two groups. Meanwhile, the preoperative occlusion period was significantly longer in the ND group. The recurrence rate after tube removal was significantly lower in the LD group (12 / 85 sides, 14.1%) compared to the ND group (27 / 72 sides, 37.5%) (p = 0.001). The patency rate at one year after removal of the lacrimal tube was 0.857 (0.754-0.919) in the LD group and 0.739 (0.617-0.828) in the ND group. In comparing patency rates by the RMST method at τ = 365 days, the RMST difference, RMST ratio, and RMTL ratio were significantly higher in the LD group at p = 0.045, 0.052, and 0.046, respectively. Conclusion: Regarding the bicanalicular silicone tube intubation, the patency rate at one year after removal was significantly higher in the thicker tubes with a diameter of 1.5 mm compared with that of a diameter of 1.0 mm for the treatment of NLDO.

scholarly journals The difference in outcome of patients with open inguinal hernia repair by using delayed absorbable sutures instead of non-absorbable sutures for mesh fixation

2020 ◽  
Vol 8 (1) ◽  
pp. 24
Author(s):  
Ali G. Mohammed Redha ◽  
Adil A. Jaber ◽  
Aqeel M. Nasser
Keyword(s):  
Hernia Repair ◽  
Mesh Fixation ◽  
Good Alternative ◽  
P Value ◽  
Absorbable Sutures ◽  
Significant Difference ◽  
The Difference ◽  
Group 2 ◽  
One Year ◽  
Group 1

Background: Different methods are found for mesh fixation in inguinal hernioplasty both open and laparoscopic. In open technique, sutures have been the method of choice for their reduced costs and surgeons’ habits. Whether absorbable instead of non-absorbable sutures can be used still a matter of debate in view of hernia recurrence and post-operative complications.Methods: This is a prospective done on 158 male patients with uncomplicated unilateral inguinal hernias. Two groups of 69 patients were evaluated after periods up to 1 year after open hernioplasty by using delayed absorbable sutures in one group (group 1) and non-absorbable sutures in the other group (group 2) for fixation of mesh.Results: In spite of a noticeable reduction in complication in the group 1 in term of number and percentage when compared with group 2 mainly chronic pain, there is no significant difference (p value>0.05). However, these results are associated with zero recurrence in both groups during a period of one year follow up.Conclusions: Delayed absorbable sutures are good alternative of non-absorbable sutures in open mesh hernia repair associated with less complications and almost no increase in chance of recurrence.  

scholarly journals A New Modification in Endoscopic Endonasal Dacryocystorhi̇nostomy Scopy-Guided Approach

2021 ◽  
Author(s):  
Akalın İrfan ◽  
Ahmet Kalkışım ◽  
Hasan Gündoğdu
Keyword(s):  
Surgical Intervention ◽  
Nasolacrimal Duct ◽  
Silicone Tube ◽  
Endoscopic Endonasal ◽  
New Approach ◽  
Surgical Success ◽  
Endoscopic Dacryocystorhinostomy ◽  
Significant Difference ◽  
Endoscopic Dcr ◽  
Anatomical Success

Abstract PurposeTo compare and assess classic endoscopic dacryocystorhinostomy (cEDCR) and scopy-guided endoscopic dacryocystorhinostomy (sEDCR) which is a new approach we developed in cases of primary nasolacrimal duct obstruction (PNLDO).MethodsFifty eyes (7 in both eyes) of 43 patients who applied with epiphora and underwent endoscopic DCR and silicone tube implantation between 2015 and 2019 were prospectively studied. cEDCR was performed on 26 of 50 eyes, and sEDCR was performed on 24 of 50 eyes. In sEDCR application, 5 cc non-ionizing opaque material was injected after punctum dilatation, lateral oblique radiographs were taken from the obstructed side with C-arm scope, and the size and location of the lacrimal sac were made visible. Thence, the most appropriate part of the passage was visualized, and surgical intervention was made through this point. Patients were followed in day 1, week 1, 3rd and 6rd mounth. Functional success was assessed according to Munk scoring, and anatomic success was assessed with nasolacrimal lavage. Two groups were compared according to surgical success, time, and complications.ResultsMean age of the cases were 47.85 (±11.8) in the cEDCR group and 54.29 (±16.23) in the sEDCR group. Female and male gender distribution was 21 (80.8%) - 5 (19.2%) for cEDCR and 15 (62.5%) - 8 (37.5%) for sEDCR, respectively. Functional success was spotted as 92.3% in the cEDCR group and 95.8% in the sEDCR group (p:1.0); anatomical success was spotted as 88.5% in the cEDCR group, and 95.8% in the sEDCR group (p:0,611). There was no significant difference between two groups. Mean surgery time was 43 minutes in the cEDCR group and 48 minutes in the EDCR group. Complications were minor and rare (p >0.05). ConclusionAs we are aware of that, our study is the first in literature in which scopy is used in endoscopic DCR. In our study, the sEDCR approach is assessed as a useful modification which improves success and facilitates surgery.

scholarly journals Accuracy of Ultrasound-Guided Pudendal Nerve Block in the Ischial Spine and Alcock’s Canal Levels: A Cadaveric Study

Pain Medicine ◽  
2020 ◽  
Vol 21 (11) ◽  
pp. 2692-2698
Author(s):  
Béatrice Soucy ◽  
Dien Hung Luong ◽  
Johan Michaud ◽  
Mathieu Boudier-Revéret ◽  
Stéphane Sobczak
Keyword(s):  
Pudendal Nerve ◽  
Ischial Spine ◽  
Ultrasound Guided ◽  
Us Guidance ◽  
Significant Difference ◽  
Alcock’S Canal ◽  
The Difference ◽  
One Year ◽  
Musculoskeletal Us ◽  
Different Levels

Abstract Background Blockade of the pudendal nerve (PN) using ultrasound (US) guidance has been described at the levels of the ischial spine and Alcock’s canal. However, no study has been conducted to compare anatomical accuracy between different approaches in targeting the PN. Objective To investigate the accuracy of US-guided injection of the PN at the ischial spine and Alcock’s canal levels. This study also compared the accuracy of the infiltrations by three sonographers with different levels of experience. Subjects Eight Thiel-embalmed cadavers (16 hemipelvises). Methods Three physiatrists trained in musculoskeletal US imaging with 12 years, five years, and one year of experience performed the injections. Each injected a 0.1-mL bolus of colored dye in both hemipelvises of each cadaver at the ischial spine and Alcock’s canal levels under US guidance. Each cadaver received three injections per hemipelvis. The accuracy of the injection was determined following hemipelvis dissection by an anatomist. Results The injections were accurate 33 times out of the total 42 attempts, resulting in 78% accuracy. Sixteen out of 21 injections at the ischial spine level were on target (76% accuracy), while the approach at Alcock’s canal level yielded 17 successful injections (81% accuracy). The difference between the approaches was not statistically significant. There was also no significant difference in accuracy between the operators. Conclusions US-guided injection of the PN can be performed accurately at both the ischial spine and Alcock’s canal levels. The difference between the approaches was not statistically significant.

scholarly journals Rhinological Status of Patients with Nasolacrimal Duct Obstruction

2021 ◽  
Author(s):  
Vasily D. Yartsev ◽  
Eugenia L. Atkova ◽  
Eugeniy O. Rozmanov ◽  
Nina D. Yartseva
Keyword(s):  
Rank Correlation ◽  
Statistical Processing ◽  
Correlation Method ◽  
Nasolacrimal Duct ◽  
Nasolacrimal Duct Obstruction ◽  
Control Group ◽  
Duct Obstruction ◽  
Rank Correlation Method ◽  
Significant Difference ◽  
The Difference

Abstract Introduction Studying the state of the nasal cavity and its sinuses and the morphometric parameters of the inferior nasal conchae, as well as a comparative analysis of obtained values in patients with primary (PANDO) and secondary acquired nasolacrimal duct obstruction (SALDO), is relevant. Objective To study the rhinological status of patients with PANDO) and SALDO). Methods The present study was based on the results of computed tomography (CT) dacryocystography in patients with PANDO (n = 45) and SALDO due to exposure to radioactive iodine (n = 14). The control group included CT images of paranasal sinuses in patients with no pathology (n = 49). Rhinological status according to the Newman and Lund-Mackay scales and volume of the inferior nasal conchae were assessed. Statistical processing included nonparametric statistics methods; χ2 Pearson test; and the Spearman rank correlation method. Results The difference in values of the Newman and Lund-Mackay scales for the tested groups was significant. A significant difference in scores by the Newman scale was revealed when comparing the results of patients with SALDO and PANDO. Comparing the scores by the Lund-Mackay scale, a significant difference was found between the results of patients with SALDO and PANDO and between the results of patients with PANDO and the control group. Conclusion It was demonstrated that the rhinological status of patients with PANDO was worse than that of patients with SALDO and of subjects in the control group. No connection was found between the volume of the inferior nasal conchae and the development of lacrimal duct obstruction.

scholarly journals Pterygia measurements are more accurate with anterior segment optical coherence tomography - A pilot study

1970 ◽  
Vol 3 (1) ◽  
pp. 9-12 ◽  
Author(s):  
MN Welch ◽  
CD Reilly ◽  
K Kalwerisky ◽  
A Johnson ◽  
SG Waller
Keyword(s):  
Optical Coherence Tomography ◽  
Standard Deviation ◽  
Pilot Study ◽  
Clinical Assessment ◽  
Anterior Segment ◽  
Optical Coherence ◽  
Slit Lamp ◽  
Significant Difference ◽  
The Mean ◽  
The Difference

Introduction: Slit-lamp beam measurements of a pterygium can be difficult to reproduce accurately. Purpose: To compare standard slit-lamp beam measurements of pterygia to computer caliper measurements of Anterior Segment Optical Coherence Tomography (OCT) images. Subjects and methods: Thirteen pterygia of ten patients were evaluated. Two physicians independently measured each pterygium using the slit lamp beam. Caliper measurements of two different OCT images of each pterygium were obtained. All measurements determined the distance from the limbus to the pterygium apex. Results: The difference in the slit lamp beam measurements of each pterygium was calculated and the mean of the differences was 0.3 and the standard deviation was 0.32. The difference in the two OCT measurements of each pterygium was also calculated and the mean of the differences was 0.1 and the standard deviation was 0.12. A two-tailed t-test demonstrated a statistically significant difference in these measurements (p = 0.0256). Conclusion: Anterior Segment Optical Coherence Tomography (OCT) gives significantly more reproducible results than the slit lamp beam for measurements of the distance of a pterygium’s apex from the limbus. This tool may provide more accurate clinical assessment of extension of pterygia onto the cornea and may be useful for research purposes. Key words: pterygium; pterygia; anterior segment optical coherence tomography; OCT DOI: 10.3126/nepjoph.v3i1.4271Nepal J Ophthalmol 2011;3(5):9-12

scholarly journals A New Modification in Endoscopic Endonasal Dacryocystorhi̇nostomy: Scopy-Guided Approach

2021 ◽  
Author(s):  
Akalın İrfan ◽  
Ahmet Kalkışım ◽  
Hasan Gündoğdu
Keyword(s):  
Surgical Intervention ◽  
Nasolacrimal Duct ◽  
Silicone Tube ◽  
Endoscopic Endonasal ◽  
New Approach ◽  
Surgical Success ◽  
Endoscopic Dacryocystorhinostomy ◽  
Significant Difference ◽  
Endoscopic Dcr ◽  
Anatomical Success

Abstract PurposeTo compare and assess classic endoscopic dacryocystorhinostomy (cEDCR) and scopy-guided endoscopic dacryocystorhinostomy (sEDCR) which is a new approach we developed in cases of primary nasolacrimal duct obstruction (PNLDO).MethodsFifty eyes (7 in both eyes) of 43 patients who applied with epiphora and underwent endoscopic DCR and silicone tube implantation between 2015 and 2019 were prospectively studied. cEDCR was performed on 26 of 50 eyes, and sEDCR was performed on 24 of 50 eyes. In sEDCR application, 5 cc non-ionizing opaque material was injected after punctum dilatation, lateral oblique radiographs were taken from the obstructed side with C-arm scope, and the size and location of the lacrimal sac were made visible. Thence, the most appropriate part of the passage was visualized, and surgical intervention was made through this point. Patients were followed in day 1, week 1, 3rd and 6rd mounth. Functional success was assessed according to Munk scoring, and anatomic success was assessed with nasolacrimal lavage. Two groups were compared according to surgical success, time, and complications.ResultsMean age of the cases were 47.85 (±11.8) in the cEDCR group and 54.29 (±16.23) in the sEDCR group. Female and male gender distribution was 21 (80.8%) - 5 (19.2%) for cEDCR and 15 (62.5%) - 8 (37.5%) for sEDCR, respectively. Functional success was spotted as 92.3% in the cEDCR group and 95.8% in the sEDCR group (p:1.0); anatomical success was spotted as 88.5% in the cEDCR group, and 95.8% in the sEDCR group (p:0,611). There was no significant difference between two groups. Mean surgery time was 43 minutes in the cEDCR group and 48 minutes in the EDCR group. Complications were minor and rare (p >0.05). ConclusionAs we are aware of that, our study is the first in literature in which scopy is used in endoscopic DCR. In our study, the sEDCR approach is assessed as a useful modification which improves success and facilitates surgery.

scholarly journals OR18-07 Laser Ablation Versus Radiofrequency Ablation for Benign Non-Functioning Thyroid Nodules: Six-Month Results of a Randomised, Parallel, Open-Label, Trial (Lara Trial)

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Roberto Cesareo ◽  
Claudio Maurizio Pacella ◽  
Valerio Pasqualini ◽  
Giuseppe Campagna ◽  
Mario Iozzino ◽  
...  
Keyword(s):  
Radiofrequency Ablation ◽  
Thyroid Nodules ◽  
Volume Reduction ◽  
High Rate ◽  
Open Label ◽  
Significant Difference ◽  
Nodule Volume ◽  
The Difference ◽  
Receive Treatment ◽  
One Year

Abstract ABSTRACT Background: Up to now, there are no direct prospective studies comparing Laser (LA) and radiofrequency ablation (RFA). We aimed to compare, in a head- to-head clinical trial, the efficacy and safety of both techniques in a population affected by solid or predominantly solid benign non-functioning thyroid nodules (BNTN). Methods. LARA is a six-month, single-use, randomized, superiority, open-label, parallel trial. We enrolled subjects with a solitary BNTN or dominant nodule characterized by pressure symptoms/cosmetic problems or patients without symptoms who experienced a volume increase &gt;20% in one year. Nodules underwent core needle biopsy (CNB) to evaluate the histological architecture. Patients were randomly assigned (1:1) to receive treatment with either LA or RFA. The primary endpoint was to evaluate the difference in nodule volume reduction between the RF and the LA group at six months. Moreover, we aimed to assess the differences between groups in the rate of nodules with greater than 50% base volume reduction (successful rate) at six months after treatment. ClinicalTrials.gov: number NCT02714946. Findings: From January 2016 to November 2018, 60 patients were randomly assigned (30 participants per group). In the whole study population, the average volume of nodules was 25 ml. The two groups were similar in terms of basal nodule volume, thyroid function, histology, symptoms/cosmetic score and procedure time. At six months, participants in the RFA group showed a reduction volume of 64·3% (95% CI: 57·5% - 71·2%) compared to 53·2% (95% CI: 47·2% - 59·2%) in the LA group (p= 0·015) and this difference was also confirmed in a linear regression model adjusted for age, baseline volume and proportion of cellular component (Laser vs. RFA percent change Delta= -12·8, P=0·018).We have not recorded any significant difference in terms of successful rate at six months after treatment between the two groups (86·7% in the RFA vs 66·7% in the LA, p=0·127). At six months, both symptoms and cosmetic scores improved (compressive symptom score: 2·13 vs 3·9 for RFA, p &lt; 0·001; 2·4 vs. 3·87 for LA, p &lt; 0·001; cosmetic score: 1·65 vs 2·2 for RFA p &lt;0·001, 1·85 vs 2·2 for LA p &lt;0·001) without any statistically significant difference between the two groups. No statistical difference between the two groups was detected at six months as regards the TSH level. High rate of cellularity negatively affects the volume reduction in RFA group (r coefficient -0·41, p=0·034) while histological features did not affect the efficacy of the LA. The adverse event rates were 37% and 43% for RFA and LA, respectively, with no requirement for hospitalization. Interpretation: Both techniques are very effective in reducing the volume of thyroid nodules. RFA appears to be more effective than LA, but both techniques showed no difference in terms of success rate six months after treatment. The safety of the two techniques is very satisfactory.

scholarly journals Longitudinal Differences in Scots pine Frost Hardiness

2004 ◽  
Vol 53 (1-6) ◽  
pp. 76-80 ◽  
Author(s):  
Bengt Andersson ◽  
A. Fedorkov
Keyword(s):  
Scots Pine ◽  
Komi Republic ◽  
Climatic Conditions ◽  
Frost Hardiness ◽  
Clinal Variation ◽  
Narrow Sense Heritability ◽  
Seed Sources ◽  
Significant Difference ◽  
The Difference ◽  
One Year

Abstract The autumn frost hardiness of Scots pine (Pinus sylvestris L.) populations from Scandinavia (57°28’-68°54’ N, 13°00’-27°00’ E) and the Komi Republic in Russia (61°30’-64°20’ N, 49°10’-54°50’ E), and open pollinated families from a population in Komi (61°43’ N, 51°07’ E) were examined in artificial freezing tests with one-year-old seedlings. The aims were to estimate genetic variation in hardiness between families of Russian origin and to compare populations of Russian (continental) and Scandinavian (maritime) origins. The longitudinal distance between the Scandinavian and Russian seed sources was associated with a significant difference in climatic conditions. At latitude 63°N the degree of continentality (the difference between July and January monthly mean temperatures) was 23.7°C for longitude 15°E in Sweden and 35.2°C for longitude 54°E in Komi. The narrow-sense heritability of frost hardiness calculated for the Russian families was 0.22. This indicates relatively high genetic control of the trait, of similar magnitude as earlier shown for populations of Scandinavian origin. Both Scandinavian and Russian populations showed a strong clinal variation in frost hardiness, northern populations being the hardiest. In addition, Russian populations were more frost hardy than Scandinavian ones from corresponding latitudes and attained the same level of hardiness as Scandinavian populations from 4.1° latitude further north. The results indicate that the longitude or continentality of the origins of Scots pine populations is associated with adaptive pressures that have significant effects on hardiness and are distinct from photoperiodic effects. When enriching breeding or production populations by including populations from remote origins it is essential to recognize not only latitudinal origin, but also longitudinal origin or temperature regime, in order to match material to the planned utilization areas.

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