Murat Deniz - Academia.edu (original) (raw)

Papers by Murat Deniz

Research paper thumbnail of The comparison of acoustic and psychic parameters of subjective tinnitus

European Archives of Oto-rhino-laryngology

We aim to assess the correlation between audiometric data, and psychotic and acoustic measures as... more We aim to assess the correlation between audiometric data, and psychotic and acoustic measures associated with subjective tinnitus (ST) and to clarify the importance of the psychological process in determining the degree of subjective annoyance and disability due to tinnitus. Fifty-four patients experiencing unilateral ST were allocated for the study. Acoustic assessment of patients including LDL (loudness discomfort levels), MML (minimum masking level) and RI (residual inhibition) was performed. Tinnitus Handicap Inventory (THI), Beck Depression Inventory (BDI) and Visual Analog Scale (VAS) tests were performed for the psychological aspects of subjective annoyance. RI was positive in 23 patients with 13 frequency-matched stimuli at 8,000 Hz. Masking treatment response was successful in 16 RI-positive patients. Mean and standard deviation (SD) of THI scores were 38.77 ± 23.63. Ten patients (%18.51) with tinnitus had ≥17 points score, which was significant for BDI. Mean and SD were 5.01 ± 2.31 for VAS-1 scores (severity of tinnitus), 7.98 ± 2.79 for VAS-2 (frequency and duration of tinnitus), 5.77 ± 2.72 for VAS-3 (discomfort level), 3.56 ± 3.30 for VAS-4 (attention deficit) and 3.31 ± 3.31 for VAS-5 (sleep disorders). A significant correlation was found between the tinnitus duration time, age, gender and THI scores (P P > 0.05). RI might be largely frequency dependent and was found as an indicator for the masking treatment response. We did not notice statistically significant correlations between audiometric data and THI and BDI. There were correlations between with VAS and LDL and with MML and RI. VAS was simpler and easier for the assessment of ST. We should consider the psychological aspects of ST and assess it as a symptom separately with acoustic and psychotic tests.

Research paper thumbnail of Significance of Serotonin Transporter Gene Polymorphism in Tinnitus

Otology & Neurotology, 2010

Objectives: To assess the role of serotonin transporter gene (SLC6A4) polymorphism in tinnitus. M... more Objectives: To assess the role of serotonin transporter gene (SLC6A4) polymorphism in tinnitus. Materials and Methods: Fifty-four consecutive patients experiencing subjective tinnitus and 174 healthy controls were allocated for the study. Psychoacoustic parameters of tinnitus were measured. Beck Depression Inventory was used to assess the depression level of the patients. Tinnitus Handicap Inventory was used to assess the severity of tinnitus. A visual analog scale was designed to measure the impact of tinnitus on quality of life of the patients. The 44-bp insertionYdeletion in the promoter region (5-HTTLPR) and 17-bp variable number tandem repeats in the second intron of the serotonin transporter gene were assessed. Results: No difference was found between the genotypes and allele frequencies of the patients and controls regarding variable number tandem repeats and 5-HTTLPR polymorphisms ( p 9 0.05). There was no association between the psycho-acoustic parameters of tinnitus and SLC6A4 polymorphism ( p 9 0.05). There was a significant association between the 5-HTTLPR polymorphism and scores from the visual analog scale of the patients ( p G 0.05). Conclusion: Generation of tinnitus signal is not associated with SLC6A4 polymorphism and possibly with serotonergic mechanisms. However, the Bll[ genotype variant of the SLC6A4 polymorphic promoter region seems associated with the limbic and autonomic nervous system symptoms of the patients with tinnitus. Therefore, serotonergic mechanisms may help explain the neurophysiological model of tinnitus, and serotonin replacement or serotonin reuptake inhibitors may increase the success rate of tinnitus treatment modalities based on the neurophysiologic model of tinnitus. Key Words: PolymorphismV SerotoninVSerotonin transporter geneVTinnitus.

Research paper thumbnail of Effects of different preservation solutions on skin graft epidermal cell viability and graft performance in a rat model

Burns, 2006

This study sought to evaluate the viable epidermal cell count of skin stored at 4 degrees C in di... more This study sought to evaluate the viable epidermal cell count of skin stored at 4 degrees C in different media, and to determine the longest time that grafts could be stored and still be used for clinical application of skin grafts. Harvested rat skin grafts were divided into four groups: saline (group 1), Roswell Park Memorial Institute-1,640 solution (RPMI) (group 2), University of Wisconsin solution (UW) (group 3), and Histidine-tryptophan-ketoglutarate solution (HTK) (group 4). After the designated storage time (7, 14, 21, 28, or 35 days), grafts were divided into two parts. Skin grafts (3 cm x 3 cm) were then autotransplanted onto full-thickness circular wound beds. Percentages of viable keratinocytes (PVK) declined significantly for skin grafts stored in UW, HTK, and saline solutions (Kruskal-Wallis, P<0.05), while there was an insignificant decline in the PVK of skin grafts stored in RPMI until the 28th day of storage (Kruskal-Wallis, P>0.05). Compared with UW, HTK, and saline, grafts stored in RPMI had significantly higher percentages of PCNA at the 14th and 21st days of storage (Mann-Whitney U-test, P<0.05). Grafts stored in RPMI had significantly lower apoptosis rates than did grafts stored in UW or HTK (P<0.05). Based on these results, we conclude that RPMI-1640 provides a better environment for skin grafts by increased quality and survival time of skin grafts, as assessed by both microscopic and macroscopic investigations.

Research paper thumbnail of Comparison of Two Different Vascular Delay Methods in a Rat Cranial Epigastric Perforator Flap Model

Annals of Plastic Surgery, 2010

The effectiveness of vascular delay in transverse rectus abdominis muscle flaps has been demonstr... more The effectiveness of vascular delay in transverse rectus abdominis muscle flaps has been demonstrated in many studies. In deep inferior epigastric perforator flaps, however, the effectiveness of ligation of deep versus superficial epigastric vessels in producing delay is unclear. Using a rat model, we compared ligation of deep and superficial vessels with each other and with a (nondelayed) control group (n = 10). One vascular delay group (n = 10) had ligation of the contralateral cranial epigastric vessels (homolog to the human deep inferior epigastric vessels); the other (n = 10) had ligation of contralateral superficial inferior epigastric vessels. One week later, cranial epigastric perforator flap elevation was performed. Both vascular techniques were effective in producing delay, and there was no statistically significant difference between the 2 groups. Ligation of superficial inferior epigastric vessels, deep inferior epigastric vessels, or both, at least 1 week prior to the deep inferior epigastric perforator flap elevation may increase the usable skin paddle area in humans.

Research paper thumbnail of Double opposing rectangular advancement elongates tension line as much as Z-plasty: An experimental study in the rat inguinal skin

Research paper thumbnail of An Alternative Method of Using an Interpositional Silicone Sheet in Tissue Expansion

Journal of Craniofacial Surgery, 2009

To reduce the rate of complications in tissue expansion, we placed a silicone sheet between the e... more To reduce the rate of complications in tissue expansion, we placed a silicone sheet between the expander and the tissue above it in a rat model. In the rats in group 1 (n = 10), the expanders were placed under the dorsal skin. The expanders were inflated with up to 45 mL of saline solution. In group 2 (n = 10), a silicone sheet was inserted between the tissue expander and the skin, after which the procedure used in group 1 was performed. The blood flow was reduced at the dome (center [C]) of the expanders in groups 1C and 2C to a degree greater than that in the expanded skin in groups 1 and 2 far periphery. However, the flow was significantly better in group 2C than in group 1C. Histologic analysis showed that the dermal and capsular tissues were significantly thicker in group 2C than in group 1C. In our opinion, placing a silicone sheet between the expander and the tissue above it seems to be beneficial. This may reduce the incidence of complications, especially the expander extrusion in this model.

Research paper thumbnail of 7-Plasty Technique for the Surgical Treatment of Congenital Longitudinal Ear Lobe Cleft

Journal of Craniofacial Surgery, 2008

The ear lobe plays an important part in the aesthetic appearance of the auricle. The clefts of th... more The ear lobe plays an important part in the aesthetic appearance of the auricle. The clefts of the ear lobe may vary in a wide range of severity from a simple notching to extensive tissue deficiency. We have operated on a congenital longitudinal ear lobe cleft using an alternative surgical method and obtained a favorable result. This method consists of a 7-plasty (or inverted L-plasty) that was performed to correct the deformity. The inner edges of the lobes were excised, and a medial extension incision was added. This helped to drop the medial part inferiorly like a back-cut so that the length of that lobe was increased. Eversion of the lateral lobe was also done, and the edges were approximated so that the angle between the extension incision and the excision line was increased to produce an obtuse angle between the 2 lines. We report an alternative method of reconstruction that can be used in longitudinal ear lobe clefts that offers a favorable result.

Research paper thumbnail of Intranasal Porous Polyethylene Implant Extrusion 7 Years After Insertion in a Patient With Hashimoto Disease

Journal of Craniofacial Surgery, 2009

We report a case of intranasal porous polyethylene implant extrusion 7 years after insertion in a... more We report a case of intranasal porous polyethylene implant extrusion 7 years after insertion in a patient with Hashimoto disease. We also discuss the possible causes of the extrusion and convey the histopathologic examination and microbiological investigation results of the samples taken from the removed implant.

Research paper thumbnail of The comparison of acoustic and psychic parameters of subjective tinnitus

European Archives of Oto-rhino-laryngology

We aim to assess the correlation between audiometric data, and psychotic and acoustic measures as... more We aim to assess the correlation between audiometric data, and psychotic and acoustic measures associated with subjective tinnitus (ST) and to clarify the importance of the psychological process in determining the degree of subjective annoyance and disability due to tinnitus. Fifty-four patients experiencing unilateral ST were allocated for the study. Acoustic assessment of patients including LDL (loudness discomfort levels), MML (minimum masking level) and RI (residual inhibition) was performed. Tinnitus Handicap Inventory (THI), Beck Depression Inventory (BDI) and Visual Analog Scale (VAS) tests were performed for the psychological aspects of subjective annoyance. RI was positive in 23 patients with 13 frequency-matched stimuli at 8,000 Hz. Masking treatment response was successful in 16 RI-positive patients. Mean and standard deviation (SD) of THI scores were 38.77 ± 23.63. Ten patients (%18.51) with tinnitus had ≥17 points score, which was significant for BDI. Mean and SD were 5.01 ± 2.31 for VAS-1 scores (severity of tinnitus), 7.98 ± 2.79 for VAS-2 (frequency and duration of tinnitus), 5.77 ± 2.72 for VAS-3 (discomfort level), 3.56 ± 3.30 for VAS-4 (attention deficit) and 3.31 ± 3.31 for VAS-5 (sleep disorders). A significant correlation was found between the tinnitus duration time, age, gender and THI scores (P P > 0.05). RI might be largely frequency dependent and was found as an indicator for the masking treatment response. We did not notice statistically significant correlations between audiometric data and THI and BDI. There were correlations between with VAS and LDL and with MML and RI. VAS was simpler and easier for the assessment of ST. We should consider the psychological aspects of ST and assess it as a symptom separately with acoustic and psychotic tests.

Research paper thumbnail of Significance of Serotonin Transporter Gene Polymorphism in Tinnitus

Otology & Neurotology, 2010

Objectives: To assess the role of serotonin transporter gene (SLC6A4) polymorphism in tinnitus. M... more Objectives: To assess the role of serotonin transporter gene (SLC6A4) polymorphism in tinnitus. Materials and Methods: Fifty-four consecutive patients experiencing subjective tinnitus and 174 healthy controls were allocated for the study. Psychoacoustic parameters of tinnitus were measured. Beck Depression Inventory was used to assess the depression level of the patients. Tinnitus Handicap Inventory was used to assess the severity of tinnitus. A visual analog scale was designed to measure the impact of tinnitus on quality of life of the patients. The 44-bp insertionYdeletion in the promoter region (5-HTTLPR) and 17-bp variable number tandem repeats in the second intron of the serotonin transporter gene were assessed. Results: No difference was found between the genotypes and allele frequencies of the patients and controls regarding variable number tandem repeats and 5-HTTLPR polymorphisms ( p 9 0.05). There was no association between the psycho-acoustic parameters of tinnitus and SLC6A4 polymorphism ( p 9 0.05). There was a significant association between the 5-HTTLPR polymorphism and scores from the visual analog scale of the patients ( p G 0.05). Conclusion: Generation of tinnitus signal is not associated with SLC6A4 polymorphism and possibly with serotonergic mechanisms. However, the Bll[ genotype variant of the SLC6A4 polymorphic promoter region seems associated with the limbic and autonomic nervous system symptoms of the patients with tinnitus. Therefore, serotonergic mechanisms may help explain the neurophysiological model of tinnitus, and serotonin replacement or serotonin reuptake inhibitors may increase the success rate of tinnitus treatment modalities based on the neurophysiologic model of tinnitus. Key Words: PolymorphismV SerotoninVSerotonin transporter geneVTinnitus.

Research paper thumbnail of Effects of different preservation solutions on skin graft epidermal cell viability and graft performance in a rat model

Burns, 2006

This study sought to evaluate the viable epidermal cell count of skin stored at 4 degrees C in di... more This study sought to evaluate the viable epidermal cell count of skin stored at 4 degrees C in different media, and to determine the longest time that grafts could be stored and still be used for clinical application of skin grafts. Harvested rat skin grafts were divided into four groups: saline (group 1), Roswell Park Memorial Institute-1,640 solution (RPMI) (group 2), University of Wisconsin solution (UW) (group 3), and Histidine-tryptophan-ketoglutarate solution (HTK) (group 4). After the designated storage time (7, 14, 21, 28, or 35 days), grafts were divided into two parts. Skin grafts (3 cm x 3 cm) were then autotransplanted onto full-thickness circular wound beds. Percentages of viable keratinocytes (PVK) declined significantly for skin grafts stored in UW, HTK, and saline solutions (Kruskal-Wallis, P<0.05), while there was an insignificant decline in the PVK of skin grafts stored in RPMI until the 28th day of storage (Kruskal-Wallis, P>0.05). Compared with UW, HTK, and saline, grafts stored in RPMI had significantly higher percentages of PCNA at the 14th and 21st days of storage (Mann-Whitney U-test, P<0.05). Grafts stored in RPMI had significantly lower apoptosis rates than did grafts stored in UW or HTK (P<0.05). Based on these results, we conclude that RPMI-1640 provides a better environment for skin grafts by increased quality and survival time of skin grafts, as assessed by both microscopic and macroscopic investigations.

Research paper thumbnail of Comparison of Two Different Vascular Delay Methods in a Rat Cranial Epigastric Perforator Flap Model

Annals of Plastic Surgery, 2010

The effectiveness of vascular delay in transverse rectus abdominis muscle flaps has been demonstr... more The effectiveness of vascular delay in transverse rectus abdominis muscle flaps has been demonstrated in many studies. In deep inferior epigastric perforator flaps, however, the effectiveness of ligation of deep versus superficial epigastric vessels in producing delay is unclear. Using a rat model, we compared ligation of deep and superficial vessels with each other and with a (nondelayed) control group (n = 10). One vascular delay group (n = 10) had ligation of the contralateral cranial epigastric vessels (homolog to the human deep inferior epigastric vessels); the other (n = 10) had ligation of contralateral superficial inferior epigastric vessels. One week later, cranial epigastric perforator flap elevation was performed. Both vascular techniques were effective in producing delay, and there was no statistically significant difference between the 2 groups. Ligation of superficial inferior epigastric vessels, deep inferior epigastric vessels, or both, at least 1 week prior to the deep inferior epigastric perforator flap elevation may increase the usable skin paddle area in humans.

Research paper thumbnail of Double opposing rectangular advancement elongates tension line as much as Z-plasty: An experimental study in the rat inguinal skin

Research paper thumbnail of An Alternative Method of Using an Interpositional Silicone Sheet in Tissue Expansion

Journal of Craniofacial Surgery, 2009

To reduce the rate of complications in tissue expansion, we placed a silicone sheet between the e... more To reduce the rate of complications in tissue expansion, we placed a silicone sheet between the expander and the tissue above it in a rat model. In the rats in group 1 (n = 10), the expanders were placed under the dorsal skin. The expanders were inflated with up to 45 mL of saline solution. In group 2 (n = 10), a silicone sheet was inserted between the tissue expander and the skin, after which the procedure used in group 1 was performed. The blood flow was reduced at the dome (center [C]) of the expanders in groups 1C and 2C to a degree greater than that in the expanded skin in groups 1 and 2 far periphery. However, the flow was significantly better in group 2C than in group 1C. Histologic analysis showed that the dermal and capsular tissues were significantly thicker in group 2C than in group 1C. In our opinion, placing a silicone sheet between the expander and the tissue above it seems to be beneficial. This may reduce the incidence of complications, especially the expander extrusion in this model.

Research paper thumbnail of 7-Plasty Technique for the Surgical Treatment of Congenital Longitudinal Ear Lobe Cleft

Journal of Craniofacial Surgery, 2008

The ear lobe plays an important part in the aesthetic appearance of the auricle. The clefts of th... more The ear lobe plays an important part in the aesthetic appearance of the auricle. The clefts of the ear lobe may vary in a wide range of severity from a simple notching to extensive tissue deficiency. We have operated on a congenital longitudinal ear lobe cleft using an alternative surgical method and obtained a favorable result. This method consists of a 7-plasty (or inverted L-plasty) that was performed to correct the deformity. The inner edges of the lobes were excised, and a medial extension incision was added. This helped to drop the medial part inferiorly like a back-cut so that the length of that lobe was increased. Eversion of the lateral lobe was also done, and the edges were approximated so that the angle between the extension incision and the excision line was increased to produce an obtuse angle between the 2 lines. We report an alternative method of reconstruction that can be used in longitudinal ear lobe clefts that offers a favorable result.

Research paper thumbnail of Intranasal Porous Polyethylene Implant Extrusion 7 Years After Insertion in a Patient With Hashimoto Disease

Journal of Craniofacial Surgery, 2009

We report a case of intranasal porous polyethylene implant extrusion 7 years after insertion in a... more We report a case of intranasal porous polyethylene implant extrusion 7 years after insertion in a patient with Hashimoto disease. We also discuss the possible causes of the extrusion and convey the histopathologic examination and microbiological investigation results of the samples taken from the removed implant.