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OBJECTIVE: The purpose of this study was to determine the positive predictive value (PPV) for diagnosis of discoid lateral meniscal tear using MR imaging and to describe various patterns of such tears in the knee. SUBJECTS AND METHODS: MR reports of 77 patients (10-67 years old) who underwent prospective MR imaging that led to a diagnosis of discoid lateral meniscal tear were correlated with arthroscopic results. MR images obtained in 71 patients confirmed to have discoid lateral meniscial tear were retrospectively reviewed for the presence, site, and pattern of discoid lateral meniscal tear, including type of displacement of the torn segment. MR abnormalities were correlated with arthroscopic findings. RESULTS: For the prospective MR interpretations, the PPV for discoid meniscus was 92%. PPV for discoid meniscal tear was 57%. PPVs for individual types of discoid meniscal tears were 46% (peripheral tear, 19/41), 76% (peripheral tear with horizontal tears, 16/21), 56% (horizontal tear, 5/9), 50% (transverse tear, 1/2), 67% (horizontal tear combined with transverse tear, 2/3), and 100% (longitudinal tear, 1/1). Peripheral tear alone and peripheral tear with horizontal tear were the most common types of tears (n = 20, 28%). Multiple tears (n = 34, 48%) were common. Displacement of the torn segments was seen in 51 patients (72%). CONCLUSION: MR imaging has a low PPV for diagnosing discoid lateral meniscal tear. Peripheral tear alone and peripheral tear with horizontal tear were the most common types of tears, and displacement of the torn segment was frequent.
PURPOSE: To determine the relative distribution of the locations of rotator cuff tears, and the sensitivity of anterior versus posterior tears on MR images. PATIENTS AND METHODS: We identified 110 consecutive patients who had a shoulder MR and either a partial-thickness or a small full-thickness rotator cuff tear diagnosed at arthroscopy. From the arthroscopy videotapes, we classified the tears as centered in the anterior or posterior half of the cuff, and as either in the critical zone or adjacent to the bony insertion. The original MR interpretation was compared with the arthroscopic findings. MR sensitivity and patient age were compared between patients with tears in the anterior and posterior halves of the cuff. In addition, in patients with partial tears less than 2 cm in diameter, an age comparison between those with tears in the critical zone and those with articular surface tears adjacent to the bony insertion (rim-rent tear) was performed. RESULTS: The tear was centered in the anterior half of the rotator cuff in 79% of the patients younger than 36 years old, and in 89% of the patients 36 years old and over. The average age of the patients with tears in the anterior half (44 years) was not significantly different from the average age of those with posterior tears (40 years) (P = 0.23). The sensitivity of MR for anterior tears was 0.69, and for posterior tears it was 0.56 (P = 0.17). The average age of the 9 patients with rim-rent tears was 31 years, while that of the 28 patients with similarly-sized partial tears not involving the insertion was 40 years old (P = 0.048). Five of the nine rim-rent tears (0.56) were interpreted correctly on the original MR report; two of the other tears were misinterpreted as intratendinous fluid but were diagnosable in retrospect. CONCLUSION: Even in patients less than 36 years old, most partial and small full-thickness rotator cuff tears are centered in the anterior half of the supraspinatus. Although our figure for MR sensitivity for these tears is lower than in recent articles, we found no significant difference between the sensitivity of MR for diagnosing posterior tears versus tears in the anterior half of the supraspinatus tendon. Rim-rent tears can be mistaken for intratendinous signal, and should be carefully looked for in younger patients with shoulder pain.
PURPOSE: In throwing athletes, partial rotator cuff tears are usually located posterior to the site of the common rotator cuff tears seen in the general nonthrowing population. However, they sometimes have tears located around the anterior aspect of the supraspinatus tendon. In this study we investigated the characteristics of anterior rotator cuff tears in throwing athletes. We then compared several factors between anterior tears and posterior tears to investigate those related to the presence of anterior tears or the occurrence of such tears. METHODS: We divided 37 athletes with partial rotator cuff tears into those with anterior tears (n = 17) and those with posterior tears (n = 20). The clinical profile, range of motion and joint laxity with patient under general anesthesia, and operative findings were retrospectively compared between the 2 groups. RESULTS: Among the 17 anterior rotator cuff tears, 12 tears were confined to the anterior one third of the supraspinatus tendon. Interestingly, concealed intratendinous degenerative tears were found in 6 shoulders. These appeared to be very shallow articular-side tears located around the attachment of the greater tuberosity, but severe tears were exposed after resection of the residual capsular portion of the tendon. Posterior capsular tightness was significantly related to the occurrence of anterior tears, whereas a greater tuberosity notch was significantly related to posterior tears. CONCLUSIONS: Anterior rotator cuff tears are not uncommon in throwing athletes, and a concealed type of tear was a representative lesion. Different mechanisms may be involved in the development of anterior and posterior rotator cuff tears resulting from throwing injuries. Posterior capsular tightness might influence the occurrence of anterior tears. LEVEL OF EVIDENCE: Level IV, prognostic case series.
OBJECTIVE: To evaluate tear film changes after phacoemulsification. METHODS: This prospective randomized study involved 68 consecutive patients with age-related cataract (79 eyes) who underwent phacoemulsification. Tear break-up time, Schirmer I test (S I t) value, corneal fluorescein staining, tear film pattern by DR-1 tear interfermetry and the height of tear meniscus were measured preoperatively and 1 day and 2, 7, 14, 30, 180 days postoperatively. RESULTS: At 1 day and 2 days postoperatively, the mean tear break-up time reduced greatly, and the number of patients who showed III to V tear film pattern, the mean S I t value, the height of tear meniscus and fluorescein staining scores increased significantly (P < 0.001 for day 1, P < 0.005 for day 2). S I t value at 7 days postoperatively (P = 0.831) and the height of tear meniscus at 14 days returned to their preoperative values (P = 1.000). The tear break-up time, corneal fluorescein staining scores and the grades of tear film pattern all recovered at 30 days postoperatively (P > 0.05). At 30 days postoperatively, 19.3% of patients showed shorter tear break-up time and less S I t value than that of preoperative day. In addition, 1/9 of the patients with normal preoperative tear film experienced dry eye at 30 days postoperatively. The cases with tear break-up time < 10 seconds compared to patients with tear break-up time >/= 10 seconds were more easily to show tear instability postoperatively (relative risk 13.5, 8.25, 20.0, 39.0, 8.6, 3.9 at 1 day and 2, 7, 14, 30, 180 postoperative days, respectively). CONCLUSION: Phacoemulsification significantly alters the tear break-up time, S I t value, corneal fluorescein staining, tear film pattern and the height of tear meniscus. Some patients with normal tear film may experience dry eye after surgery. Patients with preexisting tear break-up time < 10 seconds are easily at risk of experiencing the tear film instability postoperatively.
PURPOSE: Fibronectin plays an important role in corneal healing and has been detected previously in the tear film. To investigate the levels of fibronectin in normal human tears, the authors measured and compared fibronectin concentration in open-eye, closed-eye, and reflex tear fluid. The origin of fibronectin in the tear film was investigated by comparing fibronectin concentration in sequentially collected reflex tear samples with the concentrations of total protein and albumin in the same samples. METHODS: Open-eye and closed-eye tears were collected from 11 noncontact lens wearers. From 7 subjects, 20 uninterrupted reflex tear samples (10 microliters each) subsequently were collected, using the sneeze reflex method of stimulation, followed by an additional 10 nonstimulated tear samples (3 microliters each) immediately after cessation of stimulus. Enzyme-linked immunosorbent assays were used to determine fibronectin and albumin concentrations, and bicinchoninic acid protein assays were used to determine total protein concentration in each sample. RESULTS: Fibronectin concentration in open-eye tears (19 +/- 24 eta g/ml, range 3 to 78 eta g/ml) was significantly different (P = 0.004) from that in closed-eyes tears (4127 +/- 3222 eta g/ml, range 1177 to 11384 eta g/ml). In the first 50 microliters of reflex tears, fibronectin concentrations were low (10 +/- 23 eta g/ml), but they increased significantly (P = 0.028) after 100 microliters of reflex tears had been collected (220 +/- 126 eta g/ml). There was a further marked transient increase (767 +/- 946 eta g/ml) after cessation of stimulus. Total protein concentration in the same samples decreased significantly during reflex tear collection compared to open-eye tears, and it increased gradually after cessation of stimulus. Albumin concentration in the same samples, analyzed for two subjects only, showed a pattern similar to that for fibronectin. Dilation of conjunctival blood vessels was noted in all subjects after reflex tear collection. Administration of a topical vasoconstrictor in two subjects eliminated the increase in fibronectin concentration during reflex tearing but did not affect total protein concentration. Under reducing conditions, the molecular mass of fibronectin in open-eye and reflex tears was 240 kDa, identical to commercially available purified plasma fibronectin, whereas fibronectin in closed-eye tears was degraded into small molecular mass fragments. CONCLUSIONS: These findings suggest that fibronectin in tear fluid is derived from plasma and that the increase in concentration in closed-eye and reflex tear fluid is caused by leakage from dilated conjunctival blood vessels.
OBJECTIVE: A meniscal radial tear is a vertical tear that involves the inner meniscal margin. The tear is most frequent in the middle third of the lateral meniscus and may extend outward in any direction. We report (1) the arthroscopic incidence of radial tears, (2) MR signs that aid in the detection of radial tears and (3) our prospective accuracy in detection of radial tears. DESIGN AND PATIENTS: Three musculoskeletal radiologists prospectively read 200 consecutive MR examinations of the knee that went on to arthroscopy by one orthopedic surgeon. MR images were assessed for location and MR characteristics of radial tears. MR criteria used for diagnosis of a radial tear were those outlined by Tuckman et al.: truncation, abnormal morphology and/or lack of continuity or absence of the meniscus on one or more MR images. An additional criterion used was abnormal increased signal in that area on fat-saturated proton density or T2-weighted coronal and sagittal images. Prospective MR readings were correlated with the arthroscopic findings. RESULTS: Of the 200 consecutive knee arthroscopies, 28 patients had radial tears reported arthroscopically (14% incidence). MR readings prospectively demonstrated 19 of the 28 radial tears (68% sensitivity) when the criteria for diagnosis of a radial tear were truncation or abnormal morphology of the meniscus. With the use of the additional criterion of increased signal in the area of abnormal morphology on fat-saturated T2-weighted or proton density weighted sequences, the prospective sensitivity was 25 of 28 radial tears (89% sensitivity). There were no radial tears described in MR reports that were not demonstrated on arthroscopy (i.e., there were no false positive MR readings of radial tears in these 200 patients). CONCLUSIONS: Radial tears are commonly seen at arthroscopy. There was a 14% incidence in this series of 200 patients who underwent arthroscopy. Prospective detection of radial tears was 68% as compared with arthroscopy when the criteria as outlined by Tuckman et al. were used alone. With the use of the additional criterion of increased signal in the area of abnormal morphology on fat-saturated T2-weighted and proton density weighted sequences, the prospective sensitivity for radial tear detection as compared with arthroscopy was 89% in our series. Fat-saturated proton density and T2-weighted images greatly improve the detection of radial tears as signal intensity changes in radial tears as well as morphologic changes can be utilized for the detection of subtle tears.
It has long been assumed that unstimulated tears are more thoroughly equilibrated with epithelial secretions than stimulated tears, since they are in contact with tarsal, bulbar and corneal surfaces for longer. It was also believed from results with model solutions that soluble mucin is responsible for the observed surface tension and viscosity of tears. If longer contact means more mucin is dissolved in the aqueous tears, then the surface activity (surface tension lowered by mucin) and viscosity (raised by mucin) of tears should therefore be enhanced in unstimulated over stimulated tears. Pools of stimulated and minimally-stimulated tears were collected from a group of healthy adult volunteers by glass capillary. Viscosities were measured in the Contraves Low Shear 30 rheometer over the range of shear rates 0-130 sec-1. Surface tension was measured in the collection capillaries by a micro-technique, before and after refrigerated storage. Both surface tension and viscosity were determined for a variety of tear proteins and mucins. No significant difference was found between the viscosity/shear rate plots of stimulated and unstimulated tear samples. The viscosities of solutions of individual tear proteins were low, except for the combination of lysozyme and secretory IgA. Surface tensions were also similar in both cases, and unchanged by storage at room temperature or refrigeration, indicating no significant loss of surface-active material by adsorption on the capillary walls. Results with model mucin solutions gave a variety of results indicating either little surface activity or losses due to wall adsorption. Tear proteins, individually or in combination, did not lower surface tension to the level of tears. Tear viscosity seems not to depend on the level of dissolved mucins. This suggests either that a constant level of these is picked up even by short-term contact with ocular surfaces, or that viscosity arises from currently unknown materials which vary little with tear flow rate. This type of shear-dependent viscosity is most easily simulated in model solutions with polyionic linear macromolecules, including mucins. The contribution of individual proteins to overall viscosity is small, but combinations including lysozyme show tear-like characteristics, and may indicate that proteins whose concentration is relatively independent of tear flow rate combine with other tear components (possibly including mucins or lipids) to produce their full effect on tear viscosity. The surface tension results suggest that mucins are not of primary importance. Theories of tear film structure and performance need revision.
BACKGROUND: This study aimed to characterise the composition of the pre-ocular fluid after transplantation of the autologous submandibular gland (SMG) for patients with severe dry eye. METHODS: Stimulated and unstimulated pre-ocular fluid from 15 patients (17 eyes) with a viable SMG graft ("SMG-salivary tears"), as well as normal tears and SMG saliva (20 normal subjects/ 20 eyes), was sampled. As global tear parameters, fern pattern analysis and SDS gel electrophoresis were performed. As specific quality parameters, total protein content, secretory immunoglobulin A (SIgA), lysozyme, amylase, sodium, potassium and osmolality were measured using routine laboratory methods. The flow rate of SMG-salivary tears was determined in 5 patients by means of sequential scintillography. RESULTS: The fern pattern of SMG-salivary tears was coarse and thus more similar to normal SMG saliva than tears. SDS gel electrophoresis of the SMG-salivary tears showed albumin and two unidentified proteins in addition to the normal tear pattern. Osmolality and total protein content of SMG-salivary tears were higher than in normal SMG saliva, but still lower than in normal tears. High activities of normal tear antibacterial proteins (SIgA, lysozyme and amylase) were detected in the salivary tears. Stimulation of the secretion did not alter the composition of SMG-salivary tears. The flow rate of SMG-salivary tears was closer to that of normal tears than normal SMG saliva. CONCLUSION: Salivary tears resulting from SMG-transplantation represent condensed SMG saliva. Thus their quality is intermediate between normal tears and normal SMG saliva. High levels of secretory proteins demonstrate that the gland maintains an active function. Surgical denervation and residual tear components from the ocular surface are the most likely factors to cause the complex differences between normal SMG saliva and SMG-salivary tears. The effects of this secretion on the ocular surface are currently being evaluated in a clinical and laboratory study.
BACKGROUND: This study aimed to characterise the composition of the pre-ocular fluid after transplantation of the autologous submandibular gland (SMG) for patients with severe dry eye. METHODS: Stimulated and unstimulated pre-ocular fluid from 15 patients (17 eyes) with a viable SMG graft ("SMG-salivary tears"), as well as normal tears and SMG saliva (20 normal subjects/20 eyes), was sampled. As global tear parameters, fern pattern analysis and SDS gel electrophoresis were performed. As specific quality parameters, total protein content, secretory immunoglobulin A (SIgA), lysozyme, amylase, sodium, potassium and osmolality were measured using routine laboratory methods. The flow rate of SMG-salivary tears was determined in 5 patients by means of sequential scintillography. RESULTS: The fern pattern of SMG-salivary tears was coarse and thus more similar to normal SMG saliva than tears. SDS gel electrophoresis of the SMG-salivary tears showed albumin and two unidentified proteins in addition to the normal tear pattern. Osmolality and total protein content of SMG-salivary tears were higher than in normal SMG saliva, but still lower than in normal tears. High activities of normal tear antibacterial proteins (SIgA, lysozyme and amylase) were detected in the salivary tears. Stimulation of the secretion did not alter the composition of SMG-salivary tears. The flow rate of SMG-salivary tears was closer to that of normal tears than normal SMG saliva. CONCLUSION: Salivary tears resulting from SMG-transplantation represent condensed SMG saliva. Thus their quality is intermediate between normal tears and normal SMG saliva. High levels of secretory proteins demonstrate that the gland maintains an active function. Surgical denervation and residual tear components from the ocular surface are the most likely factors to cause the complex differences between normal SMG saliva and SMG-salivary tears. The effects of this secretion on the ocular surface are currently being evaluated in a clinical and laboratory study.
PURPOSE: To demonstrate the feasibility of indirectly measuring the precorneal tear film thickness and pre- and postlens tear film (PLTF) thickness using optical coherence tomography (OCT). METHODS: Central corneal thickness (C(1)) which includes the tear film (T) of both eyes of 40 non-contact lens wearers was measured using OCT after calibration. The mean age of the 40 subjects was 31.2 +/- 9.3 years with a mean horizontal K-reading of 7.87 mm. Rigid contact lenses with base curves 0.3- to 0.5-mm steeper than the flattest K of the eye were fitted to measure real corneal thickness (C(2)), independently of the postlens tear film. T was calculated by T = C(1) - C(2). To measure pre- and postlens tear film thickness, Focus Night & Day and Acuvue lenses (Vistakon, Johnson & Johnson Vision Care, Jacksonville, FL) were fitted on both eyes. Central soft lens thickness (L(1)), which includes the prelens tear film (P), was measured by OCT in situ and in saline in a wet cell (L(2)). P was calculated by P = L(1) - L(2). Thickness of the central cornea plus the postlens tear film (C(3)) was measured during lens wearing. Postlens tear film (PLTF) was calculated by PLTF = C(3) - C(2). RESULTS. The mean +/- SD precorneal tear film thickness was 3.3 +/- 1.5 microm (range, 0-6.9) before lens insertion and 4.7 +/- 2.3 microm (range, 0.7-11.0) after lens fitting, which was significantly thicker (paired t-test: P < 0.01). The prelens tear film thickness was 3.9 +/- 2.6 and 3.6 +/- 2.1 microm (mean +/- SD; paired t-test: P = 0.52) and the postlens tear film thickness was 4.5 +/- 2.3 and 4.7 +/- 3.1 microm (paired t-test: P = 0.08) on and under Focus Night & Day and Acuvue lenses, respectively. Post hoc tests showed that precorneal (baseline) and prelens tear films were equivalent, and each was different (thinner; Tukey honestly significant difference P < 0.05) from the postlens tear film. CONCLUSIONS: OCT can noninvasively measure the thickness of the precorneal and prelens tear film as well as the postlens tear film. The thickness of the normal precorneal tear film is approximately 3 micro m and becomes thicker after lens fitting. The postlens tear film is thicker than the precorneal and prelens tear films with soft contact lenses. The thickness of both pre- and postlens tear films appears to be independent of the investigated lens types.
PURPOSE: To correlate tear fluorescein clearance with interleukin-1alpha (IL-1alpha) concentration and gelatinase B (matrix metalloproteinase [MMP]-9) activity in the tear fluid of patients with ocular rosacea and normal control subjects. METHODS: Gelatinase activity was evaluated by gelatin zymography in tear fluid obtained from 13 patients with ocular rosacea (including 1 patient with recurrent epithelial erosion, 2 with recurrent peripheral corneal infiltrates and vascularization, and 2 patients with epithelial basement membrane dystrophy) and 13 normal subjects with normal aqueous tear production and no irritation symptoms. Tear fluorescein clearance was evaluated by measuring fluorescence in tear fluid collected from the inferior meniscus 15 minutes after instillation of 5 microl of 2% Na-fluorescein with a CytoFluor II fluorometer. Pro-MMP-9 and IL-1alpha concentrations in the tear fluid were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared with normal control subjects, patients with ocular rosacea had a greater delay of tear fluorescein clearance (P < 0.001), a higher tear IL-1alpha concentration (P < 0.001), and a greater pro-gelatinase B (92 kDa) activity (P < 0.001) in their tear fluid. The 84-kDa active form of gelatinase B was observed in 46% of the rosacea tear samples and none of the controls. The zymographic results were confirmed by ELISA that showed a significantly greater concentration of pro-MMP-9 (92 kDa) in the tear fluid of rosacea patients than controls. Delayed tear clearance was correlated with elevated tear IL-1alpha concentration (p=0.67, P < 0.001) and increased tear gelatinase B activity (p=0.84, P < 0.001). Tear IL-1alpha concentration was correlated with tear gelatinase B activity (p=0.58, P < 0.002). CONCLUSIONS: Gelatinase B (MMP-9) activity is greater in patients with ocular rosacea than in normal eyes. The majority of this activity is due to 92-kDa proform of this enzyme. This activity is correlated with delayed tear clearance and tear fluid concentration of interleukin-1alpha, a proinflammatory cytokine that has been reported to stimulate gelatinase B production. Elevated gelatinase B activity in ocular rosacea may be involved in the pathogenesis of the irritation symptoms, recurrent epithelial erosions, vascularization, and epithelial basement membrane dystrophy that develops in the corneas of patients with this condition.