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Dive into the research topics where Matti Varpula is active.

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Featured researches published by Matti Varpula.


Laryngoscope | 1998

Prospective randomized comparison of endonasal endoscopic dacryocystorhinostomy and external dacryocystorhinostomy

Jouko Hartikainen; Jukka Antila; Matti Varpula; Pauli Puukka; Heikki Seppä; Reidar Grénman

Objectives and Study Design: The advent of the rigid endonasal endoscope and the development of functional endoscopic sinus surgery (FESS) technique have awakened interest in an endonasal endoscopic dacryocystorhinostomy (EESC‐DCR) in treating nasolacrimal obstruction. This prospective, randomized study compares EESC‐DCR with traditional external dacryocystorhinostomy (EXT‐DCR) for their success rates, surgical duration, and postoperative symptoms. Patients and Methods: Sixty‐four cases in 60 patients with primary acquired nasolacrimal sac or duct obstruction were divided into two subgroups by symptoms (simple epiphora/ chronic dacryocystitis). These patients were randomized within both subgroups into two operation groups. Altogether 32 EESC‐DCRs and 32 EXT‐DCRs were performed. The final follow‐up visit was at 1 year. The patency of the lacrimal passage was investigated by irrigation and patients were questioned about their symptoms. Results: The success rate at 1 year after surgery was 75% for EESC‐DCR and 91% for EXT‐DCR after primary surgery. The difference was not statistically significant (P = .18). The success rate after secondary surgery with a follow‐up time of 1 year was 97% in both study groups. The average duration for EESC‐DCR was 38 minutes, and 78 minutes for EXT‐DCR, (P < .001). Conclusions: EXT‐DCR, when compared with EESC‐DCR, appears to give a higher, although not statistically significant, primary success rate, but the secondary success rates are equal, indicating that these two different DCR techniques are acceptable alternatives.


European Journal of Radiology | 1997

Assessment of cervical lymph node status in head and neck cancer patients: palpation, computed tomography and low field magnetic resonance imaging compared with ultrasound-guided fine-needle aspiration cytology

Timo Atula; Matti Varpula; Timo Kurki; Pekka-Juhani Klemi; Reidar Grénman

OBJECTIVE Since the assessment of lymph node metastases in head and neck cancer patients remains a major problem, the findings of different imaging methods and the role of these methods in the clinical management are compared. MATERIAL AND METHODS Palpation, computed tomography (CT) and low field magnetic resonance imaging (MRI; 0.1 T) are evaluated and compared with ultrasound-guided fine-needle aspiration cytology (US-guided FNAC) prospectively in 105 consecutive patients with a primary cancer in the head and neck region. RESULTS In the subgroup of 86 patients with palpable normal necks, CT showed lymph nodes fulfilling the radiologic criteria for malignancy in 27% (23/86), MRI in 17% (10/60) and US in 14% (12/86) of the patients US guided FNAC usually showed malignancy in necks containing lymph nodes with central necrosis on CT, but the enlarged lymph nodes that were also common on the contralateral side were often benign on cytology. In 5 patients, FNAC under US-guidance showed malignancy although none of them had lymph nodes fulfilling the radiologic criteria for malignancy. In the other subgroup of 19 patients with palpable metastatic necks, 2 patients had bilateral metastases detected by all imaging methods but not by palpation. CONCLUSION CT is superior to low field MRI in depicting small pathologic lymph nodes. Unlike lymph node structure, lymph node size is not a highly reliable criterion for malignancy. The findings must be correlated in relation to the primary disease. Since FNAC under US-guidance offers additional information about enlarged lymph nodes and since it can show malignancy in small lymph nodes not found by other methods, it can be recommended for most head and neck cancer patients irrespective of the use of CT or MRI.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1998

Obliteration of the frontal sinus cavity with bioactive glass

Matti Peltola; Jouko Suonpää; Kalle Aitasalo; Matti Varpula; Antti Yli-Urpo; Risto-Pekka Happonen

Bioactive glass (BG) is a glass ceramic material. It has been used as surgical bone replacement material in ear and oral surgery, orthopedics, and dentistry.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1996

Palpation, ultrasound, and ultrasound-guided fine-needle aspiration cytology in the assessment of cervical lymph node status in head and neck cancer patients

Timo S. Atula; Reidar Grénman; Matti Varpula; Timo Kurki; Pekka-Juhani Klemi

Lymph node status of the neck is the most important prognostic factor in head and neck cancer patients. Assessment of the lymph nodes status is still often based on palpation only, although the low accuracy of palpation is known.


Journal of Computer Assisted Tomography | 1993

Staging of uterine endometrial carcinoma with ultra-low field (0.02 T) MRI: a comparative study with CT.

Matti Varpula; Pekka J. Klemi

Objective The purpose of this investigation was to evaluate the capability of ultra-low field MRI for staging endometrial carcinoma. Materials and Methods Computed tomography and MRI were performed on 47 patients with uterine endometrial carcinoma. The results were compared with those from clinical examination and with histopathological results after operation in 43 cases. The local extension of the endometrial carcinoma was correctly staged in 77% with clinical examination, in 58% with CT, and in 88% with MRI. Results Tumor growth was overestimated by clinical examination in 21%, by CT in 35%, and by MRI in only 5%. Magnetic resonance imaging was most accurate in detecting cervical extension and was better than CT in detecting tumor invasion to the outer half of the myometrium. The sensitivities of CT and MRI in the assessment of deep myometrial invasion were 67 and 83%, respectively, the corresponding specificities being 67 and 79%. Magnetic resonance imaging at 0.02 T was not able to differentiate tumors with superficial myometrial invasion from those confined entirely to the endometrium. The detection of metastatic lymphadenopathy was difficult with all examination methods. Conclusion Our results indicate that MRI at 0.02 T is a convenient, inexpensive, and accurate imaging method for the preoperative staging of endometrial carcinoma.


Journal of Biomedical Materials Research | 2001

Clinical follow-up method for frontal sinus obliteration with bioactive glass S53P4.

Matti Peltola; Jouko Suonpää; Heli S. Määttänen; Matti Varpula; Kalle Aitasalo; Antti Yli-Urpo; Pekka Laippala

A clinical follow-up method was developed to investigate the behavior of a massive amount of bioactive glass S53P4 (BG) clinically used in frontal sinus obliteration. Two sizes of granules (0.63-0.8 mm or 0.8-1.0 mm) in 16 separate BG amounts, weight 25 g, were tested both in simulated body fluid (SBF) and in a buffer containing tris-hydroxymethyl aminomethane citric acid (TRIS-c.a) in standard conditions. The dissolution of silicon (Si) and phosphate (P) was detected with direct current plasma atom emission spectroscopy (DCP-AES) monthly up to 6 months. The BG masses were scanned both wet in the solutions and dried by computer tomography (CT), and the scans were analyzed by Region of Interest (ROI) technique. Calcium phosphate (CaP)- and silica (Si)-gel-layers were studied by scanning electron microscopy (SEM) at 1, 3, and 6 months. Cumulative loss of Si and P was stronger in TRIS-c.a than in SBF (p < 0.0001), and it was higher with smaller than with larger granules in both solutions (p < 0.0001). This was shown correspondingly by the decrease of Hounsfield units (HUs) in ROI analysis (p < 0.0001). The level of HUs was lower with dried than with wet BG (p < 0.0001). The results were compared for clinical ROI analysis of patients with obliterated frontal sinuses up to 48 months and they were parallel. The follow-up method seems to indirectly reveal the behavior of BG and the healing process in the obliterated cavity.


Obstetrics & Gynecology | 2003

Response of estrogen receptor-positive intraabdominal fibromatosis to aromatase inhibitor therapy

Pekka J. Klemi; Kalle Alanen; Sakari Hietanen; Seija Grénman; Matti Varpula; Tuula Salmi

BACKGROUND Intraabdominal fibromatosis is a rare tumor-like lesion of uncertain etiology. CASE A 49-year-old woman underwent abdominal hysterectomy and bilateral salpingooophorectomy in 1997 to treat uterine leiomyomata and ovarian fibromatosis. Postoperatively, she received estradiol 2 mg daily as hormone replacement therapy (HRT). In 2000, laparotomy performed for a large pelvic tumor revealed inoperable intra-abdominal fibromatosis. The tumor, which was positive for estrogen and progesterone receptors, resolved during aromatase inhibitor therapy. The first follow-up computed tomographic (CT) scan revealed that the tumor masses were significantly reduced in size, and successive CT scans revealed stable disease. CONCLUSION Intraabdominal fibromatosis that expresses estrogen and progesterone receptors may respond favorably to treatment with aromatase inhibitors.


Magnetic Resonance Imaging | 1992

Magnetic resonance imaging of the uterus at an ultra low (0.02 T) magnetic field.

Matti Varpula; Markku Komu; Pekka J. Klemi

In vivo pelvic imaging of 39 women and in vitro relaxation time measurements of four uterine specimens were performed using an ultra low field (0.02 T) MRI unit. Average T1 times measured in vitro at 37 degrees C for the myometrium and endometrium were 206 ms (SD 47 ms) and 389 ms (SD 21 ms), respectively. Corresponding T2 times were 95 ms (SD 20 ms) and 167 ms (SD 13 ms). The proton relaxation of almost all myometrial specimens proved to be biexponential, but of all endometrial specimens was monoexponential. Contrast measurements between endometrium versus myometrium and myometrium versus the junctional zone were performed after imaging 18 volunteer women using different pulse sequence parameters. Normal uterine structures were optimally demonstrated by SE 700/70. Relatively short repetition times could be used, because spin-lattice relaxation times were short at the low magnetic field. Consequently, the short repetition times allowed averaging of four excitations to create adequate images within an acceptable scanning time. In addition to T2-weighted images a T1-weighted inversion recovery sequence with a short inversion time of 50 ms (IR 1000/50/40) adequately differentiated the three uterine zones. Although pathologic lesions of the uterus including leiomyomas, anomalies and carcinomas were well demonstrated, especially with the T2-weighted spin echo pulse sequence, further investigations are needed to evaluate the optimal technique for ultra low field MR imaging of uterine tumors.


Magnetic Resonance Imaging | 1993

Magnetic resonance imaging of female pelvic masses and local recurrent tumors at an ultra low (0.02 T) magnetic field: Correlation with computed tomography

Matti Varpula

Pelvic MR (41 patients) and CT (36 patients) examinations were performed on 14 females with a primary pelvic complaint, and on 28 females with a suspicion of local recurrent disease of gynecologic malignant tumor. Benign cystic tumors were found in eight patients, five patients had endometriomas, one had a lymphoma, and one had a small androblastoma. Ten local recurrent tumors were confirmed histopathologically or cytologically. All cysts, one endometrioma, the lymphoma, and six recurrent tumors were detected on images obtained by our ultra low field magnetic unit. The smallest cyst detected was 16 mm in diameter. Small scattered implants of endometriosis were not discerned. The appearance of the tumors did not differ essentially from those described at high magnetic fields. Physical examination detected all 10 recurrent tumors, CT detected 8 of them, and MRI 6 out of 9 cases. The sensitivities of physical examination, CT and MRI to find recurrent diseases were 100%, 80%, and 67%, respectively. Corresponding specificities were 93%, 67%, and 80%. The results indicate that physical examination is most important in recurrent diseases. CT is the basic method for imaging malignant pelvic tumors. MR imaging at 0.02 T magnetic field provides a convenient and inexpensive method for more specific information, if CT findings are equivocal. MRI at 0.02 T is also accurate in detecting benign pelvic masses, but the findings are not very specific.


Magnetic Resonance Imaging | 1994

Magnetic resonance imaging of the uterus in vivo and in vitro at an ultra low magnetic field (0.02 T): Assessment of its normal structure and of leiomyomas

Matti Varpula; Pentti Kiilholma; Pekka J. Klemi; Markku Komu

The purpose of this investigation was to analyze the normal anatomy and leiomyomas of the uterus with an ultra low field (0.02 T) magnetic resonance imaging (MRI) device. MR imaging was performed on 18 uteri, 11 of which were imaged both preoperatively (in vivo) and as an operative specimen (in vitro), 6 only as an operative specimen, and 1 only preoperatively. All uteri were examined histologically after imaging. The junctional zone was much better delineated in vivo than in vitro, indicating that its appearance on MR is partly due to blood flow. No structures contributing to its visibility in vitro could be demonstrated histologically. Twenty leiomyomas (size range 7-79 mm) in 12 uteri were found with MRI. They were slightly better discerned in vivo than in vitro. The leiomyomas, having no degenerative changes, had a signal intensity which was the same or lower than that of the myometrium. On images obtained in vitro the signal intensity of these leiomyomas relative to that of myometrium correlated directly with their muscular content (R = 0.74, p = .002). The authors conclude that the junctional zone is a sum of physiological and structural factors, the latter being responsible for its in vitro delineation. MR imaging of the uterus in vitro did not give more information than MR imaging in vivo. All leiomyomas larger than 10 mm could be detected, indicating that MR imaging at 0.02 T is an accurate method for the imaging of the uterine leiomyomas.

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Kalle Aitasalo

Turku University Hospital

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Reidar Grénman

Turku University Hospital

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Ilpo Kinnunen

Turku University Hospital

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Jouko Suonpää

Turku University Hospital

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Markku Komu

Turku University Hospital

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Matti Peltola

Turku University Hospital

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