Publications by authors named "Ilkka Kivekäs"

31 Publications

Assessment of PIV performance in validating CFD models from nasal cavity CBCT scans.

Respir Physiol Neurobiol 2020 11 30;282:103508. Epub 2020 Jul 30.

Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland; Department of Otorhinolaryngology - Head and Neck Surgery, Tampere University Hospital, Tampere, Finland.

Objective: The aim of our study was to investigate how well Particle Image Velocimetry (PIV) measurements could serve Computational Fluid Dynamics (CFD) model validation for nasal airflow.

Material And Methods: For the PIV measurements, a silicone model of the nose based on cone beam computed tomography (CBCT) scans of a patient was made. Corresponding CFD calculations were conducted with laminar and two turbulent models (k-ω and k-ω SST).

Results: CFD and PIV results corresponded well in our study. Especially, the correspondence of CFD calculations between the laminar and turbulent models was found to be even stronger. When comparing CFD with PIV, we found that the results were most convergent in the wider parts of the nasal cavities.

Conclusion: PIV measurements in realistically modelled nasal cavities succeed acceptably and CFD calculations produce corresponding results with PIV measurements. Greater model scaling is, however, necessary for better validations with PIV and comparisons of competing CFD models.
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http://dx.doi.org/10.1016/j.resp.2020.103508DOI Listing
November 2020

Three-Dimensional Printing of the Nasal Cavities for Clinical Experiments.

Sci Rep 2020 01 16;10(1):502. Epub 2020 Jan 16.

Department of Otorhinolaryngology - Head and Neck Surgery, Tampere University Hospital, Tampere, Finland.

3D printing has produced many beneficial applications for surgery. The technique´s applicability in replicating nasal cavity anatomy for clinical use has not been studied. Our aim was to determine whether 3D printing could realistically replicate the nasal cavities and the airflow passing through them from a clinical point of view. We included Cone Beam Computed Tomography (CBCT) scans of five patients with symptoms of chronic nasal congestion. These CBCT scans were used to print plastic 3D prints of the nasal cavities, which were also CBCT scanned and the measurements were compared. The results in vivo were higher than the results in vitro in maxillary sinus volumes with a ratio of 1.05 ± 0.01 (mean ± SD) and in the nasal cavities with a ratio of 1.20 ± 0.1 (mean ± SD). Linear measurements in vitro were very close to those in vivo. Rhinomanometric results showed some differences, but rhinomanometric graphs in vitro were close to the graphs in vivo. 3D printing proved to be a suitable and fast method for replicating nasal cavity structures and for the experimental testing of nasal function. It can be used as a complementary examination tool for rhinomanometry.
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http://dx.doi.org/10.1038/s41598-020-57537-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6965131PMC
January 2020

Mucociliary function of the eustachian tube in the eustachian tube dysfunction.

Acta Otolaryngol 2019 Mar 14;139(3):238-242. Epub 2019 Mar 14.

a Department of Otorhinolaryngology, University of Tampere, Faculty of Medicine and Life Sciences, Tampere University Hospital , Tampere , Finland.

Background: Most of the tests to evaluate the eustachian tube (ET) function are focused on the ventilation function of the ET.

Aim: Here we evaluate mucociliary function of the ET in patients with ET dysfunction.

Materials And Methods: Ten patients with ET dysfunction were enrolled into the study. Six patients had chronic tympanic membrane retraction and four patients had chronic middle ear effusion (MEE). All patients had intact tympanic membranes. Tympanometry and clinical examinations were done to all patients. Mucociliary function was evaluated with technetium labeled albumin and blue dye. Tympanometry and clinical examinations were done to six patients with chronic tympanic membrane retraction and four patients with chronic middle ear effusion (MEE). Mucociliary function of the ET was evaluated with technetium labeled albumin and blue dye placed into middle ear through an intact tympanic membrane and followed from nasopharynx ET orifice (blue dye) and with gamma camera (technetium).

Results: Blue dye was observed in tubal orifice in six (6 of 10) patients during 30 min observation. Five of those patients (5 of 6) had tympanic membrane retraction and one patient (1 of 6) had MEE. Tracer activity decreased from middle ear in six (6 of 10) patients. Four of those patients had tympanic membrane retraction and two had MEE.

Conclusion: Mucociliary function of the ET seems to be better in patients with tympanic membrane retraction than patients with middle ear effusion.

Significance: Mucociliary function of the ET is an important function for middle ear aeration, blue dye test is easily available to be used also in clinical practice.
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http://dx.doi.org/10.1080/00016489.2018.1562218DOI Listing
March 2019

Three-Dimensional Volumetric Evaluation of the Maxillary Sinuses in Chronic Rhinosinusitis Surgery.

Ann Otol Rhinol Laryngol 2018 Dec 22;127(12):931-936. Epub 2018 Sep 22.

1 Department of Ear and Oral Diseases, Tampere University Hospital and Department of Otorhinolaryngology, University of Tampere, Tampere, Finland.

Introduction:: The objective of this study was to ascertain whether the 3-dimensional volumetric measurement method could be used for the evaluation of operative treatment results in patients with chronic rhinosinusitis.

Methods:: A total of 61 adult patients with chronic rhinosinusitis were analyzed. Cone-beam computed tomographic images of the paranasal sinuses were examined preoperatively and at 12 months postoperatively. The results were compared using the Sino-Nasal Outcome Test (SNOT-22) and the Lund-Mackay (LM) and Zinreich modified staging systems.

Results:: The mean change in pneumatized volumes in the maxillary sinuses after operative treatment per patient was 2.0 ± 7.5 cm ( P = .146). The median for volumetric change was 0.97 cm (range, -11.6 to 33.6 cm). Both the LM and Zinreich modified LM staging systems showed no change in 32 of 61 patients (53%). The alterations in patients' maxillary sinuses measured using the volumetric measurement method correlated well with changes in Zinreich's modified LM staging (-0.77, P < .01).

Conclusions:: The 3D volumetric method is more sensitive in detecting small alterations in pneumatized volumes of the maxillary sinuses than Zinreich's modified LM staging and LM staging. The method correlates better with Zinreich's modified LM staging than with LM staging.
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http://dx.doi.org/10.1177/0003489418801386DOI Listing
December 2018

The effect of inferior turbinate surgery on ciliated epithelium: A randomized, blinded study.

Laryngoscope 2019 01 27;129(1):18-24. Epub 2018 Aug 27.

Department of Otorhinolaryngology, Tampere University Hospital, Tampere, Finland.

Objectives/hypothesis: The aim of this study was to evaluate statistically the effects of radiofrequency ablation, diode laser, and microdebrider-assisted inferior turbinoplasty techniques on ciliated epithelium and mucociliary function.

Study Design: Prospective randomized study.

Methods: A total of 66 consecutively randomized adult patients with enlarged inferior turbinates underwent either a radiofrequency ablation, diode laser, or microdebrider-assisted inferior turbinoplasty procedure. Assessments were conducted prior to surgery and 3 months subsequent to the surgery. The effect on ciliated epithelium was evaluated using a score based on the blinded grading of the preoperative and postoperative scanning electron microscopy images of mucosal samples. The effect on mucociliary function, in turn, was evaluated using saccharin transit time measurement.

Results: The score of the number of cilia increased statistically significantly in the radiofrequency ablation (P = .03) and microdebrider-assisted inferior turbinoplasty (P = .04) groups, but not in the diode laser group. The score of the squamous metaplasia increased statistically significantly in the diode laser group (P = .002), but not in the other two groups. There were no significant changes found between the preoperative and postoperative saccharin transit time values in any of the treatment groups.

Conclusions: Radiofrequency ablation and microdebrider-assisted inferior turbinoplasty are more mucosal preserving techniques than the diode laser, which was found to increase the amount of squamous metaplasia at the 3-month follow-up. The number of cilia seemed to even increase after radiofrequency ablation and microdebrider-assisted inferior turbinoplasty procedures, but not after diode laser. Nevertheless, the mucociliary transport was equally preserved in all three groups.

Level Of Evidence: 1b Laryngoscope, 129:18-24, 2019.
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http://dx.doi.org/10.1002/lary.27409DOI Listing
January 2019

In vitro detection of common rhinosinusitis bacteria by the eNose utilising differential mobility spectrometry.

Eur Arch Otorhinolaryngol 2018 Sep 24;275(9):2273-2279. Epub 2018 Jul 24.

Department of Otorhinolaryngology, Faculty of Medicine and Life Sciences, University of Tampere and Tampere University Hospital, PL 2000, 33521, Tampere, Finland.

Acute rhinosinusitis (ARS) is a sudden, symptomatic inflammation of the nasal and paranasal mucosa. It is usually caused by respiratory virus infection, but bacteria complicate for a small number of ARS patients. The differential diagnostics between viral and bacterial pathogens is difficult and currently no rapid methodology exists, so antibiotics are overprescribed. The electronic nose (eNose) has shown the ability to detect diseases from gas mixtures. Differential mobility spectrometry (DMS) is a next-generation device that can separate ions based on their different mobility in high and low electric fields. Five common rhinosinusitis bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Pseudomonas aeruginosa) were analysed in vitro with DMS. Classification was done using linear discriminant analysis (LDA) and k-nearest neighbour (KNN). The results were validated using leave-one-out cross-validation and separate train and test sets. With the latter, 77% of the bacteria were classified correctly with LDA. The comparative figure with KNN was 79%. In one train-test set, P. aeruginosa was excluded and the four most common ARS bacteria were analysed with LDA and KNN; the correct classification rate was 83 and 85%, respectively. DMS has shown its potential in detecting rhinosinusitis bacteria in vitro. The applicability of DMS needs to be studied with rhinosinusitis patients.
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http://dx.doi.org/10.1007/s00405-018-5055-8DOI Listing
September 2018

Balloon Eustachian Tuboplasty: Systematic Review of Long-term Outcomes and Proposed Indications.

J Int Adv Otol 2018 Apr;14(1):112-126

Department of Otorhinolaryngology - Head and Neck Surgery, Head and Neck Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.

Balloon Eustachian tuboplasty (BET) aims to improve the function of the Eustachian tube (ET). The objective of this study was to review the long-term outcome of BET and present the process and results of outlining indications for BET by the Finnish Otosurgical Society. The literature review is based on a database search performed in May 2017. The search resulted in 100 individual articles, which were screened for relevance. Five articles fulfilled the inclusion criteria (follow-up ≥12 months). Five additional articles (follow-up, 6-11 months) were analyzed to obtain supportive information. The proposed BET indications were constituted in the 2016 annual meeting of the Finnish Otosurgical Society. The workshop included a review of the Eustachian tube physiology, middle ear aeration mechanisms, and BET outcome studies. Thereafter, the members of the Society first voted and then discussed 14 cases in order to conclude whether BET was indicated in each case, and subsequently, a consensus statement on the indications for BET was outlined. The long-term follow-up studies were heterogeneous regarding the Eustachian tube dysfunction (ETD) definition, patient selection, follow-up duration, additional treatments, and outcome measures. The current, but limited, evidence suggests that BET is effective in the long-term. However, more long-term studies with uniform criteria and outcome measures as well as placebo-controlled studies are needed. The proposed indications for BET by the Finnish Otosurgical Society include chronic bothersome symptoms referring to ETD, ETD-related symptoms when pressure changes rapidly, or recurring serous otitis media. With the current evidence, we suggest treating only adults with BET.
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http://dx.doi.org/10.5152/iao.2018.4769DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6354503PMC
April 2018

Long-term results of atresiaplasty in patients with congenital aural atresia.

Acta Otolaryngol 2018 Jul 9;138(7):621-624. Epub 2018 Feb 9.

a Department of Otorhinolaryngology , Tampere University Hospital, and School of Medicine, University of Tampere , Tampere , Finland.

Objectives: To evaluate long-term benefits of atresiaplasty on hearing and the impact of surgery on quality of life (QoL) in congenital aural atresia (CAA) patients.

Methods: We evaluated the long-term hearing results, the impact of atresiaplasty on QoL, the meatal diameter of the operated ear canal, and the cumulative number of post-operative hospital visits in 14 CAA patients, on average, 12 years (range: 4-17 years) post-operatively.

Results: The mean preoperative pure tone average (PTA) was 61 dB HL. The postoperative short-term PTA was 36 dB HL and the long-term PTA was 51 dB HL. The mean total Glasgow Benefit Inventory (GBI) score was 16 (range: -11-39), showing the positive benefit of atresiaplasty on QoL. The mean postoperative diameter of the auditory meatus was 6 mm. The average number of hospital outpatient visits during the first postoperative year was 10.

Conclusion: Surgery for CAA is a demanding operation with variable anatomical and hearing outcomes. Atresiaplasty operations should be centralized to hospitals with large numbers of such patients to ensure sufficient levels of surgical experience. Bone-anchored hearing devices or middle-ear implants should be considered as a first-line option because they offer good hearing predictability.
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http://dx.doi.org/10.1080/00016489.2018.1431402DOI Listing
July 2018

A prospective, randomized, placebo-controlled study of inferior turbinate surgery.

Laryngoscope 2018 09 2;128(9):1997-2003. Epub 2018 Feb 2.

Department of Otorhinolaryngology, Tampere University Hospital, Tampere, Finland.

Objectives/hypothesis: The purpose of this study was to compare radiofrequency ablation, diode laser, and microdebrider-assisted inferior turbinoplasty techniques in the treatment of chronic nasal obstruction caused by inferior turbinate enlargement, and to compare these techniques with a placebo procedure.

Study Design: Prospective, randomized, single-blinded, placebo-controlled study.

Methods: A total of 98 consecutive patients with enlarged inferior turbinates due to persistent year-round rhinitis were randomized into a placebo, radiofrequency ablation, diode laser, and microdebrider-assisted inferior turbinoplasty groups in a ratio of 1:2:2:2. All the procedures were carried out under local anesthesia with the patients' eyes covered. Assessments were conducted prior to surgery and 3 months subsequent to the surgery.

Results: The severity of nasal obstruction measured by visual analog scale score decreased statistically significantly in all the groups, including placebo. Radiofrequency ablation (P = .03), diode laser (P = .02), and microdebrider-assisted inferior turbinoplasty (P = .04) all decreased the symptom score of the severity of nasal obstruction statistically significantly more compared to the placebo procedure.

Conclusions: The placebo effect had a large role in the overall improvement of the severity of nasal obstruction after the inferior turbinate surgery. However, all three techniques provided a statistically significant additional reduction of the severity of nasal obstruction compared to the placebo procedure.

Level Of Evidence: 1b. Laryngoscope, 128:1997-2003, 2018.
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http://dx.doi.org/10.1002/lary.27103DOI Listing
September 2018

Eustachian Tube Dysfunction-Related Symptoms in Chronic Nasal Obstruction Caused by Inferior Turbinate Enlargement.

Ann Otol Rhinol Laryngol 2017 Dec 4;126(12):798-803. Epub 2017 Oct 4.

1 Department of Otorhinolaryngology, Tampere University Hospital, Tampere, Finland.

Objective: The aim of this study was to evaluate the relationship between chronic nasal obstruction caused by inferior turbinate enlargement and Eustachian tube dysfunction-related symptoms using the Eustachian Tube Dysfunction Questionnaire (ETDQ-7) as an assessment method.

Methods: A total of 80 adults were enrolled. Group 1 comprised consecutive patients with enlarged inferior turbinates and group 2 comprised healthy controls. The ETDQ-7 scores and tympanometry results of both groups were analyzed and compared.

Results: The median total scores of the ETDQ-7 in groups 1 and 2 were 1.9 (interquartile range, 1.4-2.8) and 1.1 (interquartile range, 1.0-1.7), respectively ( P < .001). There was no significant difference in the abnormal tympanometry results between the groups. There was no significant difference in the ETDQ-7 total score between the patients with allergic sensitization and other patients in group 1.

Conclusions: Patients with inferior turbinate enlargement have more symptoms related to Eustachian tube dysfunction than healthy controls. Most patients with Eustachian tube dysfunction had normal tympanometry and normal otoscopy, which indicates a baro-challenge-induced Eustachian tube dysfunction. Whether the patient has allergic sensitization or not does not seem to cause a difference in symptoms related to Eustachian tube dysfunction.
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http://dx.doi.org/10.1177/0003489417735538DOI Listing
December 2017

The effect of inferior turbinate surgery on ear symptoms.

Laryngoscope 2018 03 22;128(3):568-572. Epub 2017 Aug 22.

Department of Otorhinolaryngology, Tampere University Hospital, Tampere, Finland.

Objective: The aim of this placebo-controlled study was to evaluate the effect of various inferior turbinate surgery techniques on Eustachian tube dysfunction-related symptoms.

Study Design: Outcomes were evaluated using the Eustachian Tube Dysfunction Questionnaire (ETDQ-7) and tympanometry results.

Methods: A total of 72 consecutively blinded and randomized adult patients with enlarged inferior turbinates due to persistent year-round rhinitis underwent either a radiofrequency ablation, diode laser, microdebrider-assisted inferior turbinoplasty, or sham surgery procedure. Assessments were conducted prior to surgery and 3 months subsequent to the surgery.

Results: In the evaluation of all patients, radiofrequency ablation, microdebrider-assisted inferior turbinoplasty, and sham surgery procedures decreased the ETDQ-7 total score significantly. In a three-way analysis of covariance, there were no significant differences in the results between sham surgery and any of the active treatment procedures. Allergic sensitization, sex, and age also had no effect on the results. There were no significant changes in the pre- and postoperative amounts of abnormal tympanometry curves or in the pre- and postoperative tympanometric peak pressure values in the actively treated patients or in the sham surgery group.

Conclusion: The improvement of Eustachian tube dysfunction-related symptoms due to surgery of the anterior half of the inferior turbinate was found to be equal to placebo. The findings of this study do not support the use of reduction of the anterior half of the inferior turbinate as a sole procedure intended to treat the ear symptoms assessed by the ETDQ-7 questionnaire.

Level Of Evidence: 1b. Laryngoscope, 128:568-572, 2018.
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http://dx.doi.org/10.1002/lary.26823DOI Listing
March 2018

Hybrid cochlear implantation: quality of life, quality of hearing, and working performance compared to patients with conventional unilateral or bilateral cochlear implantation.

Eur Arch Otorhinolaryngol 2017 Oct 31;274(10):3599-3604. Epub 2017 Jul 31.

Department of Ear and Oral Diseases, Tampere University Hospital, P.O. Box 2000, 33521, Tampere, Finland.

The objective of the present study is to evaluate the effect of hybrid cochlear implantation (hCI) on quality of life (QoL), quality of hearing (QoH), and working performance in adult patients, and to compare the long-term results of patients with hCI to those of patients with conventional unilateral cochlear implantation (CI), bilateral CI, and single-sided deafness (SSD) with CI. Sound localization accuracy and speech-in-noise test were also compared between these groups. Eight patients with high-frequency sensorineural hearing loss of unknown etiology were selected in the study. Patients with hCI had better long-term speech perception in noise than uni- or bilateral CI patients, but the difference was not statistically significant. The sound localization accuracy was equal in the hCI, bilateral CI, and SSD patients. QoH was statistically significantly better in bilateral CI patients than in the others. In hCI patients, residual hearing was preserved in all patients after the surgery. During the 3.6-year follow-up, the mean hearing threshold at 125-500 Hz decreased on average by 15 dB HL in the implanted ear. QoL and working performance improved significantly in all CI patients. Hearing outcomes with hCI are comparable to the results of bilateral CI or CI with SSD, but hearing in noise and sound localization are statistically significantly better than with unilateral CI. Interestingly, the impact of CI on QoL, QoH, and working performance was similar in all groups.
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http://dx.doi.org/10.1007/s00405-017-4690-9DOI Listing
October 2017

Balloon Eustachian tuboplasty under local anesthesia: Is it feasible?

Laryngoscope 2017 May 3;127(5):1021-1025. Epub 2017 Feb 3.

Department of Otorhinolaryngology-Head and Neck Surgery, Head and Neck Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.

Objective: To study whether balloon Eustachian tuboplasty (BET) is a feasible and safe procedure under local anesthesia.

Study Design: Prospective multicenter case-control study.

Methods: Patients undergoing either BET (n = 13) or endoscopic sinus surgery (ESS) (n = 12) under local anesthesia, with the possibility of sedation and analgesia, were monitored during the procedure and recovery period for possible adverse effects. After the procedure, the patients responded to a questionnaire assessing their experience.

Results: No adverse effects were detected in the BET group. Patients in the BET group reported similar Visual Analog Scale scores for pain during the operation as the ESS group (5.0 ± 0.7 vs. 3.2 ± 0.7, mean ± standard error of the mean). However, patients in the BET group experienced more discomfort (4.2 ± 0.6 vs. 2.5 ± 0.3, respectively, P = 0.049). Seventy-seven and 92% of the patients in the BET and ESS groups, respectively, considered the anesthesia and pain relief to be sufficient. Patients from both the BET and ESS groups were almost devoid of pain 1 to 2 hours postoperatively (0.8 ± 0.2 and 1.4 ± 0.3, respectively). In total, 12 of 13 patients in the BET group, and all 12 patients in the ESS group, would choose local anesthesia with sedation and analgesia if they needed to undergo the same procedure again.

Conclusion: BET is a safe and feasible procedure under monitored anesthesia care, including local anesthesia along with sedation and analgesia. There is need for further methodological improvement to reduce pain and discomfort during the operation.

Level Of Evidence: 4. Laryngoscope, 127:1021-1025, 2017.
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http://dx.doi.org/10.1002/lary.26488DOI Listing
May 2017

Significance of imaging in the diagnosis of olfactory disorder.

Ear Nose Throat J 2017 Feb;96(2):E13-E17

Department of Otorhinolaryngology, Tampere University Hospital, Teiskontie 35, 33521 Tampere, Finland.

The aim of this retrospective analysis was to examine olfactory disorders among the patients in the Ear, Nose, and Throat Clinic of Tampere University Hospital, Finland, from 2001 to 2011, and to evaluate the necessity of imaging in the examination of patients with olfactory disorders. Charts of 143 consecutive patients with a primary olfactory disorder were examined, and 69 patients who had undergone the necessary testing were included in the study. The most common causes of olfactory disorder were upper respiratory infection (23%), chronic rhinosinusitis (19%), head trauma (17%), and allergic or nonallergic rhinitis (6%). In 25% of the patients, no obvious cause for the symptoms was found. Computed tomography (CT) scans were normal in 37 of 52 (71%) patients and magnetic resonance imaging was normal in 21 of 25 (84%) patients. No intracranial or intranasal tumors were found in the overall cohort. Of the patients with additional symptoms (facial pain, headache, nasal discharge, or stuffiness), 58% had chronic rhinosinusitis. Of the patients with no additional symptoms or signs associated with chronic rhinosinusitis on clinical evaluation, only 2% had chronic rhinosinusitis on imaging. Only the detection of chronic rhinosinusitis and head trauma had clinical value in the determination of the etiology. A sinonasal CT scan should be considered in patients who have at least one symptom associated with sinusitis in addition to an olfactory disorder to confirm the etiology and to find those patients who may benefit from medical therapy or surgical treatment.
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http://dx.doi.org/10.1177/014556131709600213DOI Listing
February 2017

Critical distance between the cartilaginous Eustachian tube and the internal carotid artery.

Eur Arch Otorhinolaryngol 2017 Jan 8;274(1):73-77. Epub 2016 Jul 8.

Department of Otorhinolaryngology, School of Medicine, University of Tampere, Tampere, Finland.

During the last decade, endoscopic surgery of the Eustachian tube (ET) has been advocated for ET dilatory dysfunction and for patulous ET. The internal carotid artery (ICA) and the ET are closely related, and knowledge of their surgical anatomy has become essential. This study was designed to establish the anatomical relationships between the endoscopically critical area along the full length of the cartilaginous ET and its closest association with the ICA. The perpendicular distance between the ET lumen and the ICA was measured from head magnetic resonance images (MRI) at three levels: (A) cartilaginous and bony ET junctional point, (B) mid cartilaginous ET point, and (C) the nasopharyngeal orifice of the cartilaginous ET. Totally, 200 sides were reviewed in MRI scans of 229 patients. The mean distances for each level were: A = 4.3 mm (range 1.6-10.4 mm), B = 25 mm (range 9.0-61.6 mm), and C = 62 mm (range 34.3-84.4 mm). The perpendicular distance between ET and ICA at the nasopharyngeal orifice is large, but the distance shortens quickly while moving from the nasopharyngeal orifice of the ET to the junctional point of the ET. The potential for complications to the ICA rises as the surgical field moves closer to the isthmus of the ET because of the decreasing distance between the ET and the ICA.
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http://dx.doi.org/10.1007/s00405-016-4187-yDOI Listing
January 2017

Quality of Life and Hearing Eight Years After Sudden Sensorineural Hearing Loss.

Laryngoscope 2017 04 21;127(4):927-931. Epub 2016 Jun 21.

Department of Ear and Oral Diseases, Tampere University Hospital, Tampere, Finland.

Objectives/hypothesis: To explore long-term hearing results, quality of life (QoL), quality of hearing (QoH), work-related stress, tinnitus, and balance problems after idiopathic sudden sensorineural hearing loss (ISSNHL).

Study Design: Cross-sectional study.

Methods: We reviewed the audiograms of 680 patients with unilateral ISSNHL on average 8 years after the hearing impairment, and then divided the patients into two study groups based on whether their ISSNHL had recovered to normal (pure tone average [PTA] ≤ 30 dB) or not (PTA > 30 dB). The inclusion criteria were a hearing threshold decrease of 30 dB or more in at least three contiguous frequencies occurring within 72 hours in the affected ear and normal hearing in the contralateral ear. Audiograms of 217 patients fulfilled the criteria. We reviewed their medical records; measured present QoL, QoH, and work-related stress with specific questionnaires; and updated the hearing status.

Results: Poor hearing outcome after ISSNHL was correlated with age, severity of hearing loss, and vertigo together with ISSNHL. Quality of life and QoH were statistically significantly better in patients with recovered hearing, and the patients had statistically significantly less tinnitus and balance problems. During the 8-year follow-up, the PTA of the affected ear deteriorated on average 7 dB, and healthy ear deteriorated 6 dB.

Conclusion: Idiopathic sudden sensorineural hearing loss that failed to recover had a negative impact on long-term QoL and QoH. The hearing deteriorated as a function of age similarly both in the affected and the healthy ear, and there were no differences between the groups. The cumulative recurrence rate for ISSNHL was 3.5%.

Level Of Evidence: 4 Laryngoscope, 127:927-931, 2017.
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http://dx.doi.org/10.1002/lary.26133DOI Listing
April 2017

Eustachian Tube Mucosal Inflammation Scale Validation Based on Digital Video Images.

Otol Neurotol 2015 Dec;36(10):1748-52

*Department of Otorhinolaryngology, Tampere University Hospital and the University of Tampere, Tampere, Finland †Department of Otolaryngology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, U.S.A. ‡Department of Otorhinolaryngology, Helsinki University Hospital, Helsinki, Finland.

Background: The most common cause for Eustachian tube dilatory dysfunction is mucosal inflammation. The aim of this study was to validate a scale for Eustachian tube mucosal inflammation, based on digital video clips obtained during diagnostic rigid endoscopy.

Methods: A previously described four-step scale for grading the degree of inflammation of the mucosa of the Eustachian tube lumen was used for this validation study. A tutorial for use of the scale, including static images and 10 second video clips, was presented to 26 clinicians with various levels of experience. Each clinician then reviewed 35 short digital video samples of Eustachian tubes from patients and rated the degree of inflammation. A subset of the clinicians performed a second rating of the same video clips at a subsequent time. Statistical analysis of the ratings provided inter- and intrarater reliability scores.

Results: Twenty-six clinicians with various levels of experience rated a total of 35 videos. Thirteen clinicians rated the videos twice. The overall correlation coefficient for the rating of inflammation severity was relatively good (0.74, 95% confidence interval, 0.72-0.76). The intralevel correlation coefficient for intrarater reliability was high (0.86). For those who rated videos twice, the intralevel correlation coefficient improved after the first rating (0.73, to 0.76), but improvement was not statistically significant.

Conclusion: The inflammation scale used for Eustachian tube mucosal inflammation is reliable and this scale can be used with a high level of consistency by clinicians with various levels of experience.
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http://dx.doi.org/10.1097/MAO.0000000000000895DOI Listing
December 2015

Single-Sided Deafness: The Effect of Cochlear Implantation on Quality of Life, Quality of Hearing, and Working Performance.

ORL J Otorhinolaryngol Relat Spec 2015 30;77(6):339-45. Epub 2015 Sep 30.

Department of Otorhinolaryngology, Tampere University Hospital, University of Tampere, Tampere, Finland.

Aims: To evaluate the effect of a cochlear implant (CI) on quality of life (QoL), quality of hearing (QoH), and working performance in patients with single-sided deafness (SSD).

Methods: Using specific questionnaires, we measured QoL, QoH, and working performance in 7 SSD patients scheduled for CI surgery of the affected ear. Sound localization and speech perception in noise were also assessed. All questionnaires and tests were performed before the CI surgery and at 6 and 12 months after CI activation.

Results: The QoL, QoH, sound localization, and speech perception in noise had improved statistically significantly after CI surgery. Communication with co-workers became easier, and the patients were less fatigued after the working day.

Conclusions: CI clearly improves QoL, QoH, and working performance in patients with SSD.
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http://dx.doi.org/10.1159/000439176DOI Listing
September 2016

Pharmacological agents for the prevention of vestibular migraine.

Cochrane Database Syst Rev 2015 Jun 21(6):CD010600. Epub 2015 Jun 21.

ENT Department, Hospital Alvarez Buylla, Murias s/n, Mieres, Asturias, Spain.

Background: Vestibular migraine is a common cause of episodic vertigo. Many preventive treatments have been proposed for this condition, including calcium antagonists, beta-blockers, antidepressants, anticonvulsants, selective 5-HT1 agonists, serotonin antagonists and non-steroidal anti-inflammatory drugs (NSAIDs).

Objectives: To assess the effects of pharmacological agents for the prevention of vestibular migraine.

Search Methods: The Cochrane Ear, Nose and Throat Disorders Group (CENTDG) Trials Search Co-ordinator searched the CENTDG Trials Register; Central Register of Controlled Trials (CENTRAL 2015, Issue 5); PubMed; EMBASE; CINAHL; Web of Science; Clinicaltrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 5 June 2015.

Selection Criteria: Randomised controlled trials (RCTs) in adults (over 18 years) with a diagnosis of vestibular migraine orprobable vestibular migraine according to the Bárány Society/International Headache Society (IHS) criteria, treated in any setting, comparing pharmacological treatments used in the prevention of vestibular migraine, including beta-blockers, calcium antagonists, anticonvulsants, antidepressants, serotonin antagonists and non-steroidal anti-inflammatory drugs (NSAIDs) against placebo or no treatment.

Data Collection And Analysis: We used the standard methodological procedures expected by The Cochrane Collaboration.

Main Results: Our literature search identified 558 reports, however only 11 were sufficiently relevant for further assessment. We excluded two studies because they did not use the IHS diagnostic criteria for vestibular migraine. We excluded a further eight studies for various reasons related to their design (e.g. lack of placebo or no treatment comparator), aim (e.g. treatment of vestibular migraine rather than prevention) or conduct (e.g. early termination). We identified one ongoing study comparing metoprolol to placebo. The results of this study are awaited; recruitment of the last patient is expected by the end of 2016.

Authors' Conclusions: We found no evidence from RCTs to answer the question set out in the review objectives. This review has identified the need for well-designed randomised controlled trials to answer questions about the efficacy of current and new treatments.
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http://dx.doi.org/10.1002/14651858.CD010600.pub2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6494480PMC
June 2015

Unilateral common cavity deformity: Recurrent meningitis due to insufficient newborn hearing screening.

Int J Pediatr Otorhinolaryngol 2015 Jun 23;79(6):926-928. Epub 2015 Mar 23.

Department of Otorhinolaryngology, Tampere University Hospital and the University of Tampere, Tampere, Finland.

Insufficient newborn hearing screening may leave the other ear with undetected hearing loss. Subsequently, the missed pathology behind the impairment may have potential risk for severe infections. We describe a case of recurrent Streptococcus pneumoniae meningitis in an infant with unilateral common cavity deformity. The diagnosis of the deaf left ear was delayed due to insufficient newborn hearing screening and not until the second meningitis the pathology behind the deafness was confirmed. Subtotal petrosectomy was performed unsuccessfully and resulted in another meningitis. We highlight the importance of proper newborn hearing screening and surgical technique to treat cochlear malformations.
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http://dx.doi.org/10.1016/j.ijporl.2015.03.013DOI Listing
June 2015

Sequential bilateral cochlear implantation improves working performance, quality of life, and quality of hearing.

Acta Otolaryngol 2015 May 13;135(5):440-6. Epub 2015 Feb 13.

Department of Otorhinolaryngology, Tampere University Hospital and the University of Tampere , Tampere.

Conclusions: This prospective study shows that working performance, quality of life (QoL), and quality of hearing (QoH) are better with two compared with a single cochlear implant (CI). The impact of the second CI on the patient's QoL is as significant as the impact of the first CI.

Objectives: To evaluate the benefits of sequential bilateral cochlear implantation in working, QoL, and QoH.

Methods: We studied working performance, work-related stress, QoL, and QoH with specific questionnaires in 15 patients with unilateral CI scheduled for sequential CI of another ear. Sound localization performance and speech perception in noise were measured with specific tests. All questionnaires and tests were performed before the second CI surgery and 6 and 12 months after its activation.

Results: Bilateral CIs increased patients' working performance and their work-related stress and fatigue decreased. Communication with co-workers was easier and patients were more active in their working environment. Sequential bilateral cochlear implantation improved QoL, QoH, sound localization, and speech perception in noise statistically significantly.
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http://dx.doi.org/10.3109/00016489.2014.990056DOI Listing
May 2015

Is there an optimal location for tympanostomy tube placement?

Laryngoscope 2015 Jul 13;125(7):1513-4. Epub 2015 Jan 13.

Department of Otolaryngology & Communication Enhancement, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, U.S.A.

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http://dx.doi.org/10.1002/lary.25127DOI Listing
July 2015

Histopathology of balloon-dilation Eustachian tuboplasty.

Laryngoscope 2015 Feb 22;125(2):436-41. Epub 2014 Aug 22.

Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts; Department of Otorhinolaryngology, Tampere University Hospital and the University of Tampere, Tampere, Finland.

Objectives/hypothesis: Surgical intervention of the Eustachian tube (ET) has become increasingly common in the past decade, and balloon dilation has shown promising results in recent studies. It is unclear how balloon dilation enhances ET function. Our aim was to evaluate histological changes in the ET's mucosal lumen comparing before balloon dilation, immediately after, and postoperatively.

Study Design: Case series.

Methods: Thirteen patients with bilateral ET dysfunction were enrolled. Biopsies of the ET mucosa were obtained just before balloon dilation; immediately after; and in three cases, 5 to 12 weeks postoperatively. Specimens were retrospectively examined under light microscopy by two pathologists blinded to the clinical information and whether specimens were pre- or postballoon dilation.

Results: Preoperative biopsies were characterized by inflammatory changes within the epithelium and submucosal layer. Immediate response to balloon dilation was thinning of the mucosa, shearing of epithelium and crush injury to the submucosa, especially to lymphocytic infiltrates. Postoperative biopsies demonstrated healthy pseudocolumnar epithelium and replacement of lymphocytic infiltrate with a thinner layer of fibrous tissue.

Conclusion: Reduction of inflammatory epithelial changes and submucosal inflammatory infiltrate appeared to be the principal result of balloon dilation. The balloon may shear or crush portions of inflamed epithelium but usually spared the basal layer, allowing for rapid healing. Additionally, it appeared to effectively crush lymphocytes and lymphocytic follicles that may become replaced with thinner fibrous scar. Histopathology of the ET undergoing balloon dilation demonstrated effects that could reduce the overall inflammatory burden and may contribute to clinical improvement in ET function.

Level Of Evidence: 4.
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http://dx.doi.org/10.1002/lary.24894DOI Listing
February 2015

Balloon Dilation of the Cartilaginous Portion of the Eustachian Tube.

Otolaryngol Head Neck Surg 2014 07 4;151(1):125-30. Epub 2014 Apr 4.

Department of Otolaryngology and Communication Enhancement Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA.

Objective: Studies of balloon Eustachian tuboplasty (BET) have shown encouraging results in small series with short follow-ups. Our pilot study suggested that patients with protracted otitis media with effusion (OME) or atelectasis of the tympanic membrane (TM) could benefit from BET.

Study Design: A prospective study where subjects act as their own controls. Patients from the pilot study and additional cases were enrolled in this cohort with long-term follow-up.

Setting: Regional Academic Center.

Subjects And Methods: Out of 80 patients who underwent BET, 41 consecutive Eustachian tube (ET) operations were included. Subjects' inclusion criteria were OME and/or TM atelectasis, type B or C tympanograms, and inability to inflate their middle ears by Valsalva maneuver. All patients had longstanding ET dysfunction relieved only by repeated tympanostomies. Outcomes included ability to perform a Valsalva maneuver, audiometry, tympanometry, videoendoscopy of the ET with mucosal inflammation rating scores, and otomicroscopy.

Results: All cases were dilated successfully, without significant complications. Mean follow-up was 2.5 years (range, 1.5-4.2 years). Eighty percent (33/41) could do a Valsalva maneuver postoperatively; none of these ears required new tympanostomy tubes and subjective symptoms were relieved. Tympanometry results showed overall improvement. Nine patients had persistent perforations and 3 declined removal of the tube. Subjective symptoms were not relieved for 10% (4/41).

Conclusion: The results show that BET can effectively improve ET function in ears with OME or atelectasis. The procedure is well tolerated and without significant complications. The follow-up continues and we are investigating possible reasons for failures.
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http://dx.doi.org/10.1177/0194599814529538DOI Listing
July 2014

Comparison of stapedotomy minus prosthesis, circumferential stapes mobilization, and small fenestra stapedotomy for stapes fixation.

Otol Neurotol 2014 Apr;35(4):e123-9

*Department of Otolaryngology & Communication Enhancement, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, U.S.A.; †Istanbul Goztepe Training and Research Hospital, Ear Nose Throat Department, Istanbul, Turkey; ‡Department of Otorhinolaryngology, Tampere University Hospital and the University of Tampere, Tampere, Finland; §Department of Otolaryngology, University of Ottawa, Ottawa, Canada; and ∥Department of Otolaryngology, University of California Los Angeles, California, U.S.A.

Objective: To compare the outcomes of 3 surgical techniques for primary stapes fixation: stapedotomy minus prosthesis (STAMP), circumferential stapes mobilization (CSM), and small fenestra stapedotomy (SFS).

Study Design: Retrospective review of 277 primary cases operated for stapes fixation from 1997 to 2007.

Setting: Tertiary academic center.

Patients: Consecutive adult and pediatric cases operated for conductive hearing loss because of stapes fixation.

Interventions: STAMP was performed for otosclerosis limited to the anterior footplate, CSM was conducted for congenital stapes fixation, SFS was performed for more extensive otosclerosis or anatomic contraindications to STAMP/CSM.

Main Outcome Measures: Pure-tone audiometry was performed preoperatively and postoperatively (3-6 wk) and the most recent long-term results (≥ 12 mo).

Results: Ninety-nine ears in 90 patients had audiologic follow-up data over 12 months. Sixty-seven ears (68%) underwent SFS, 16 (16%) STAMP, and 16 (16%) CSM. There was significant improvement in average air conduction (AC) thresholds and air-bone gap (ABG) for all techniques. Mean ABG for SFS closed from 29 to 7.1 dB (SD, 6.0), for STAMP from 29 to 3.8 dB (SD, 5.8 dB), and for CSM from 34 to 20 dB (SD, 8.2 dB). AC results were better in the STAMP than in the SFS group, especially in high frequencies. Bone conduction improvements were seen in all groups, highest in STAMP (4.3 dB) and CSM (3.8 dB) groups, but the differences between groups were not statistically significant.

Conclusion: Satisfactory hearing results were achieved with all the techniques, and STAMP showed better hearing outcomes, especially in high frequencies. CSM is a good option for children and patients in whom it is desirable to avoid a footplate fenestration or prosthesis. CSM and STAMP had significantly higher rates of revision for refixation than SFS.
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http://dx.doi.org/10.1097/MAO.0000000000000280DOI Listing
April 2014

Minimally invasive functional approach for cholesteatoma surgery.

Laryngoscope 2014 Oct 24;124(10):2386-92. Epub 2014 Mar 24.

Department of Otolaryngology and Communication Enhancement, Boston Children's Hospital, and Department of Otology and Laryngology, Harvard Medical School, Boston, Massachusetts, U.S.A.; Department of Otolaryngology, University of Ottawa, Ottawa, Canada.

Objectives/hypothesis: Report the efficacy of a functional minimally invasive approach for cholesteatoma surgery.

Study Design: Retrospective review of surgical cases performed between 1996 and 2008.

Methods: One hundred sixty-nine patient charts were reviewed in which ears with primary cholesteatomas that extended beyond the mesotympanum were operated on with a plan for canal wall up (CWU) mastoidectomy. The surgical approach consisted of progressive exposure from transcanal to postauricular tympanoplasty to CWU mastoidectomy, as needed, to identify and lyse the fibrous attachments that bind the capsule to the surrounding mucosa. Endoscopic guidance was employed as appropriate to minimize exposure needs. Any planned second-stage operations were attempted with a transcanal approach if appropriate and with endoscopic assistance.

Results: One hundred eighty-four ears of 169 patients were included. The median age was 32 years (range, 1-79 years). The mean follow-up was 3.2 years (range, 1-11 years). Eighty-three (45%) were planned for a second-look operation, and three (2%) required unplanned second operations. The overall recurrence rate was 24/184 (13%), and the unexpected residual rate was 5/184 (3%). The residual rate with endoscopy (5/119, 4%,) or without endoscopy (1/65, 2%), were not significantly different. Hearing results in 156 ears improved significantly, from a preoperative pure-tone average (PTA) of 41 dB to a postoperative PTA average of 29 dB (P < .0001).

Conclusions: A functional minimally invasive approach to cholesteatoma surgery provided equivalent residual rates but higher recurrence rates compared to published canal wall down mastoidectomy. Endoscopic techniques were helpful in providing adequate views while minimizing exposure.
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http://dx.doi.org/10.1002/lary.24633DOI Listing
October 2014

Bilateral temporal bone otosyphilis.

Otol Neurotol 2014 Feb;35(2):e90-1

*Boston Children's Hospital, Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, U.S.A.; †Departments of Otorhinolaryngology, Tampere University Hospital, and ‡Department of Otorhinolaryngology, University of Tampere; and §Department of Radiology, Tampere University Hospital, Tampere, Finland.

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http://dx.doi.org/10.1097/MAO.0b013e3182a3603fDOI Listing
February 2014

[Lump in the throat].

Duodecim 2009 ;125(6):630-3

Keski-Suomen Keshussairaalan Korva, Nenä-ja, Kurkkutautien Vastuualue, Jyväskylä.

A sensation of a lump in the throat will often cause fear of tumor. Underlying the symptom is only seldom a tumor, which is, however, malignant in about 97 to 99% of cases of hypopharyngeal occurrence. Excessive alcohol consumption and smoking constitute the their greatest risk factors. We present a patient case relating to a rare benign tumor of the hypopharynx (giant fibrovascular polyp, GFP).
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May 2009

Ex vivo drug and irradiation sensitivities in hypermutated and unmutated forms of chronic lymphocytic leukemia cells.

Leuk Res 2003 Apr;27(4):337-41

Department of Clinical Chemistry, HYKS (Jorvi Hospital), Espoo, Finland.

Several investigators have now established that chronic lymphocytic leukemia (CLL) is not a uniform disease entity, since approximately half of the cases of CLL have undergone immunoglobulin V region (IgV) hypermutation, whereas the other half display unmutated Ig genes. The median survival time of mutated CLL (M-CLL) cases has been shown to be approximately twice as long as that for unmutated CLL (UM-CLL), but no clear explanation for this difference is currently available. In this work, we have investigated a cohort of previously untreated CLL patients, to see whether the ex vivo sensitivities of leukemic cells of 16 UM-CLL patients differ from those of 8 M-CLL patients, using nine different drugs and two types of irradiation. Our results demonstrated very similar ex vivo sensitivities and tumor cell heterogeneity of sensitivity of UM-CLL and M-CLL cells when tested against chlorambucil, 2-chloro-2'-deoxyadenosine, cyclosporin A, cis-platinum(II)diammine-dichloride, doxorubicin hydrochloride, 2-fluoroadenine-9-beta-D-arabinofuranoside, prednisolone sodium succinate, verapamil, vincristine, gamma-irradiation, and UV-irradiation. This indicates that de novo chemo/radiosensitivity cannot explain the survival difference observed between UM-CLL and M-CLL.
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http://dx.doi.org/10.1016/s0145-2126(02)00169-8DOI Listing
April 2003

Relationships of in vitro sensitivities tested with nine drugs and two types of irradiation in chronic lymphocytic leukemia.

Leuk Res 2002 Nov;26(11):1035-41

Laboratory of Molecular Hematology, Department of Clinical Chemistry, Laboratory Center of Tampere University Hospital, P.O. Box 2000, FIN 33521, Tampere, Finland.

Extensive research into mechanisms of cytotoxic drug and irradiation resistance have produced few clinically encouraging results. In this report, we apply correlation analyses to drug and irradiation response results from a cohort of 36 classical B chronic lymphocyte leukemia (CLL) patients. Nine drugs and two types of irradiation were selected according to their usefulness in CLL therapy or on the basis of their otherwise interesting mechanisms of action. Part of the results concerning individual drugs have been previously published, but new correlation analyses are presented in this paper. Altogether 2376 duplicate cultures were performed in order to determine ID(80) values, i.e. doses causing an 80% inhibition in 4-day cultures when leucine incorporation was used as an indicator of cells vitality. Non-parametric Spearman's rank order correlation confirmed a tight relationship between 2-chlorodeoxyadenosine and fludarabine, as expected. Surprisingly, correlation between two P-glycoprotein-dependent drugs, vincristine and doxorubicin, was not demonstrable. A number of entirely unexpected correlations were identified between drugs with very different mechanisms of action: (i) chlorambucil and gamma-irradiation; (ii) 2-chlorodeoxyadenosine and vincristine; (iii) 2-chlorodeoxyadenosine and gamma-irradiation; (iv) fludarabine and cis-platin; (v) doxorubicine and gamma-irradiation; (vi) prednisolone and cyclosporin A; (vii) vincristine and verapamil. Our findings emphasize: (i) the usefulness of fresh tumor cells instead of cell lines in cytotoxicity studies; (ii) the great variation in cytotoxicity in individual patients, i.e. tumor cell heterogeneity, as well as patient heterogeneity; and (iii) an entirely unexpected finding that there were tight relationships in drug and irradiation responses between substances supposed to act with very different mechanisms.
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http://dx.doi.org/10.1016/s0145-2126(02)00050-4DOI Listing
November 2002