Evaluation of the Golden Ratio in Nasal Conchae for Surgical Anatomy.

PURPOSE: The golden ratio is reached by the fractal model of the number sequence which is known as the "Fibonacci series" and has a convergent ratio of approximately 1.618 between 2 consecutive Fibonacci numbers. Golden ratio relationships have been shown in several plants in the nature and several organs and structures in the human body. The conchae, which form an important part of the nasal valve, have a special geometric significant in terms of providing turbulence to the laminar airflow that passes to the nasal cavity. METHODS: This study made golden ratio calculations on 34 adults aged 20 to 45 years over computed tomography (CT) images. Totally, 34 volunteers (male, n = 18 and female, n = 16) with no nasal pathologies participated in the study. Using Adobe Photoshop, golden ratio calculations were made by applying the Fibonacci spiral on the images that best showed the conchae and meatuses on the CT images. RESULTS: The intersection points of the spiral that was projected on the inferior and middle nasal concha were determined as S0, S1, S2, S3, and S4. The distances of S0-S1, S1-S2, S2-S3, and S3-S4 were measured. The concha measurements of the women showed significantly similar values to the golden ratio constant of ∼1.618 in the RS3/S4 and LS3/S4 measurements. CONCLUSION: We found that the S3/S4 region that captured the golden ratio in our study corresponds to the base part of the inferior nasal concha, and its place of spiraling in the nasal cavity is observed to have an important role in creating vortices.

Prognostic value role of radiofrequency lesion size by cardiac magnetic resonance imaging on outcomes of ablation in patients with ischemic scar-related ventricular tachycardia: A single center pilot study.

Inadequate ablation lesion formation may be responsible for post-ablation ventricular tachycardia (VT) recurrences.We aimed to evaluate whether visualisation of radiofrequency (RF) lesion size by cardiac magnetic resonance imaging (CMR) has any role in predicting adequacy of lesion and in estimating outcome.Retrospective pilot studyNine consecutive patients (8 male, age 60 ±â€Š13 years) underwent ablation for sustained VT because of ischemic scar were evaluated for pre- and post-procedure scar tissue by CMR to characterize ablation lesions. Microvascular obstruction (MVO) surrounded by late gadolinium enhancement was defined as irreversible RF lesion. All patients were followed for at least 6 months for recurrences.Five of the patients had previous inferior myocardial infarction (MI), whereas remaining 4 had anterior MI. Acute procedural success, as defined by termination of the arrhythmia without recurrence in 30 minutes, was attained in all patients. Contrast enhancement and wall motion abnormality in presumed infarction area were confirmed by pre-ablation CMR images. MVO was detected at the reported ablation site in 6/9 patients, all arrhythmia- and symptom-free at median 24 months (range 8-38 months) follow-up. In remaining 3 patients who had VT recurrence (clinical VT in 2, sustain VT with a new morphology in 1), MVO was not detected despite achievement of acute procedural success. There was no correlation with pre-ablation scar size and clinical arrhythmia recurrence.CMR is a useful imaging modality to guide ablation procedures by detecting scar tissue. Additionally MVO seen by post-procedural imaging may be related to adequacy of RF ablation lesions and may correlate with clinical outcome.

Role of diffusion-weighted MRI in the differential diagnosis of endometrioid and non-endometrioid cancer of the uterus.

Background Many publications have examined the relationship between apparent diffusion coefficient (ADC) values and tumor grade in endometrial cancer. Nevertheless, none were designed to evaluate according to the histopathological type of endometrioid and non-endometrioid tumors. Purpose To evaluate the role of diffusion-weighted imaging (DWI) in the differential diagnosis of endometrioid and non-endometrioid cancer of the uterus, by comparing them with contrast-enhanced magnetic resonance imaging (MRI) findings. Material and Methods Institutional review board approval and informed consent were obtained. The MRI findings of 63 patients with endometrial cancer were retrospectively evaluated and divided into four groups: Grades I, II, and III endometrioid tumors, and non-endometrioid tumors. ADC values, DWI quotients ( b = 1000 s/mm2), and post-contrast signal intensities between lesions and the myometrium (b1000q-Cq values) were evaluated. The one-way-ANOVA, student's t-test, Kruskal-Wallis test, and receiver operating characteristic (ROC) analysis were used for statistical evaluation. Results Mean ADC values were 0.86 ± 0.14 in Grade I, 0.80 ± 0.7 in Grade II, 0.71 ± 0.14 in Grade III for endometrioid tumors, and 0.70 ± 0.12 in non-endometrioid tumors. There was a significant difference in ADC values between Grade I and Grade III ( P = 0.006), and non-endometrioid tumors ( P = 0.003). The difference was also significant between Grades I + II and Grade III ( P = 0.009), and non-endometrioid tumors ( P = 0.004). Besides, there was a significant difference between endometrioid and non-endometrioid tumors ( P = 0.022). However, when considering b1000q (F = 0.640, P = 0.593) and Cq (χ2 = 6.233; P = 0.101), no significant difference was detected among the groups. Conclusion The difference in ADC values between the endometrioid and non-endometrioid tumors was statistically significant. However, the difference in DWI and contrast-enhancement findings were not statistically significant. Furthermore, the mean ADC values had an inverse relationship with tumor grade in the endometrioid cancer group.

Role of diffusion weighted MRI in the differential diagnosis of endometrial cancer, polyp, hyperplasia, and physiological thickening.

Our purpose was to evaluate the role of diffusion-weighted imaging (DWI) in the diagnosis of various common pathologies of the uterine cavity, by comparing them with contrast-enhanced MRI findings. One hundred sixty-four patients with lesions in endometrial cavity were included in the study. The patients were grouped in four (one malignant and three benign groups). We have observed that the differences of the apparent diffusion coefficient, b1000q, and Cq values between various common benign and malignant lesions were statistically significant (P<.001). However, the differences of the values between benign groups were not statistically significant (P>.05). Alternatively, endometrial polyp group's signal intensity on DWI was different than the other groups.

Excision efficiency of radioguided occult lesion localization in reoperative thyroid and parathyroid surgery.

BACKGROUND: The purpose of this study was to investigate the efficiency of a radioguided occult lesion localization technique in reoperative thyroid and parathyroid procedures in patients who had undergone previous neck exploration for thyroid or parathyroid disease. METHODS: Twenty-one consecutive patients who were scheduled for reoperative thyroid or parathyroid surgery were studied. The indication for reoperation was recurrent papillary thyroid cancer (PTC) in eight patients, completion thyroidectomy for PTC in eight patients who had previously undergone a bilateral subtotal thyroidectomy, recurrent goiter in two patients, primary hyperparathyroidism in two patients, and recurrent parathyroid cancer in one patient. Ninety minutes before surgery, 0.1 mL of Technetium-99m (0.2 mCi)-labeled macroaggregated albumin was injected directly into the lesion under ultrasonographic guidance. During surgery, a handheld gamma probe was used to localize and excise the lesions. The background and postexcisional site radioactivities were compared to confirm the completeness of each procedure. The radiation dose in the operating room environment, duration of surgery, and postoperative complication rates were evaluated in all patients. In patients with PTC, the change in serum thyroglobulin (Tg) following surgery was noted. RESULTS: Thirty lesions were marked and excised. The postexcisional bed gamma counts (610 ± 141) were markedly decreased compared with the pre-excisional site counts (21,415.8 ± 4993.4; p = 0.0001). The ratio of the postexcisional and background counts (4.6 ± 4.3) was significantly lower than the ratio of the pre-excisional and background counts (173.7 ± 156.4; p = 0.0001). The mean operation duration was 53.3 ± 7.5 minutes. The dose absorbed by the hands of the surgeon was estimated as 0.07 ± 0.02 and 0.15 ± 0.05 millisievert/h when one or three lesions were marked, respectively. One patient developed postoperative transient hypoparathyroidism. After surgery, serum Tg levels dropped to <2 ng/mL in 86% (6/7) of the patients with PTC whose preoperative serum Tg was elevated. CONCLUSIONS: The radioguided occult lesion localization technique was efficient in the perioperative identification of thyroid and parathyroid tumors in patients who were undergoing reoperation for PTC and hyperparathyroidism.