Early identification of keratoconus using pachymetric indexes obtained with spectral domain optical coherence tomography.

PURPOSE: To evaluate the diagnostic ability of pachymetric indexes obtained with Spectral Domain Optical Coherence Tomography (SD-OCT) for early detection of keratoconus (Kc). METHODS: 64 patients with Kc in at least one eye (95 eyes, 46 men and 18 women, average age 27.84 ±13.50), 59 healthy control subjects (100 eyes, 28 men and 31 women, average age 27.15 ±16.14). All patients underwent detailed clinical examination, topography and anterior segment OCT. 37 subjects (37 eyes, 27 men and 10 women, average age 24.23 ± 14.24) having one eye with manifest Kc and the fellow eye without clinical signs of Kc were identified. We studied two groups of pachymetric indexes: C1-C2, M1-M2, pCLMI, Pmin-P2 (Group 1 indexes) and PPD, PSD, PSSD and PASD (Group 2 indexes). A ROC (Receiver Operating Characteristic) curve was developed to compare the diagnostic accuracy, relative sensitivity and specificity for each index. RESULTS: In manifest keratoconus, C1-C2, M1-M2, and pCLMI are significantly higher compared to the control group (P<0.0001); for suspect keratoconus, all Group 1 indexes are significantly higher compared to healthy subjects (P<0.0001) excluding M1-M2 obtained using a constant area circle (P = 0.02). Furthermore, for manifest and suspect keratoconus, PPD, PSD, PSSD and PASD are significantly higher compared to the control group (P <0.0001). CONCLUSION: The studied pachymetric indexes in patients with Kc have high diagnostic accuracy and are statistically significant when compared with healthy subjects (p<0.0001) and can provide a useful tool for keratoconus screening.

Dermatofibrosarcoma protuberans.

Dermatofibrosarcoma protuberans (DFSP) is a relatively unusual, locally aggressive cutaneous tumor of intermediate malignancy, that most frequently occurs with a slight predominance in young adult men on the trunk and proximal extremities. It arises from the dermis and invades deeper subcutaneous tissues (fat, fascia, muscle, bone), but, despite its local invasiveness, it rarely metastasizes (5% of cases). Currently, the cause of DFSP is unknown. A 54-year-old woman presented with an asymptomatic, red-violaceous ovalar plaque on the left submammary area. The lesion had sharply delineated borders and showed two overlying hanging outgrowths, one smooth and flesh colored and the other reddish and with a cobblestone appearance. Histological and immunohistochemical studies confirmed the diagnosis of DFSP. This unusual presentation of DFSP is presented and discussed.

Echocardiographic assessment of right and left ventricular function after single-lung transplantation.

To evaluate the impact of single-lung transplantation on right and left ventricular performance and to identify potential preoperative characteristics that could predict postoperative outcome, a large group of patients were retrospectively evaluated by means of serial Doppler echocardiography. Twenty-six of 57 consecutive single-lung transplant patients had satisfactory Doppler echocardiographic studies before and after surgery. A significant reduction in right ventricular diastolic and systolic areas and an increase in right ventricular fractional area were noted after transplantation. The left ventricular contractility remained unchanged. In addition, significant reduction in right atrial area, right ventricular free wall thickness, and tricuspid regurgitation were also seen. Paradoxical septal motion present in eight patients before the procedure resolved in all of them after single-lung transplantation. Transthoracic echocardiography is a useful technique to document improvement in right ventricular function in 63% of patients following single-lung transplantation. Preoperative paradoxical septal motion identifies single-lung transplant recipients who have the largest postoperative right ventricular area reduction and fractional area increase. Alternative imaging modalities should be sought for single-lung transplant candidates in whom conventional transthoracic echocardiography is suboptimal.

A 2000-year tree ring record of annual temperatures in the sierra nevada mountains.

Tree ring data have been used to reconstruct the mean late-season (June through January) temperature at a timberline site in the Sierra Nevada, California, for each of the past 2000 years. Long-term trends in the temperature reconstruction are indicative of a 125-year periodicity that may be linked to solar activity as reflected in radiocarbon and auroral records. The results indicate that both the warm intervals during the Medieval Warm Epoch ( approximately A.D. 800 to 1200) and the cold intervals during the Little Ice Age ( approximately A.D. 1200 to 1900) are closely associated with the 125-year period. Significant changes in the phase of the 125-year temperature variation occur at the onset and termination of the most recent radiocarbon triplet and may indicate chaotic solar behavior.