Intraoperative Performance and Early Postoperative Outcomes Following Phacoemulsification With Three Fluidic Systems: A Randomized Trial.

PURPOSE: To compare intraoperative performance and early postoperative outcomes following phacoemulsification with two systems using active fluidics and one using gravity-based fluidics. METHODS: In this prospective randomized trial, 200 eyes were randomized to the traditional and Active Sentry groups (n = 80 eyes each) where the Centurion Vision System was used with traditional or Active Sentry (Alcon Laboratories, Inc) hand-pieces, respectively, or the Infinit group (n = 40 eyes) where the Infiniti Vision System (Alcon Laboratories, Inc) was used. Within the traditional and Active Sentry groups, there were two subgroups with low (30 mm Hg) or high (55 mm Hg) intraocular pressure (IOP) used. Outcome measures compared were: cumulative dissipated energy (CDE), percentage change in central corneal thickness (CCT) at 1 day, 1 week, and 1 month, anterior chamber cells at 1 day and 1 week, rate of rise and fall of IOP following occlusion break, corneal endothelial cell density (ECD), and macular thickness 6 months postoperatively. RESULTS: CDE was significantly lower in group II compared to the traditional group (2.96 ± 1.4 vs 4.14 ± 2.2, P = .001). With 30 mm Hg IOP, the Active Sentry group had significantly less percentage change in CCT at 1 week postoperatively compared to the traditional handpiece group (0.01% vs 0.02%, P = .008). Incidence of anterior chamber cells less than grade 2 on day 1 was significantly higher in the Active Sentry group (82.9% vs 52%, P = .03). Percentage change in ECD was significantly lower in the Active Sentry group (-0.957 vs -0.98%, P = .005). Significantly faster rise of IOP to baseline following occlusion break was seen in the Active Sentry group. CONCLUSIONS: The use of Active Sentry handpiece was associated with lower CDE, less postoperative increase in CCT, fewer anterior chamber cells, and faster rise of IOP following occlusion break. [J Refract Surg. 2024;40(5):e304-e312.].

A multicenter proof-of-concept study on deep learning-based intraoperative discrimination of primary central nervous system lymphoma.

Accurate intraoperative differentiation of primary central nervous system lymphoma (PCNSL) remains pivotal in guiding neurosurgical decisions. However, distinguishing PCNSL from other lesions, notably glioma, through frozen sections challenges pathologists. Here we sought to develop and validate a deep learning model capable of precisely distinguishing PCNSL from non-PCNSL lesions, especially glioma, using hematoxylin and eosin (H&E)-stained frozen whole-slide images. Also, we compared its performance against pathologists of varying expertise. Additionally, a human-machine fusion approach integrated both model and pathologic diagnostics. In external cohorts, LGNet achieved AUROCs of 0.965 and 0.972 in distinguishing PCNSL from glioma and AUROCs of 0.981 and 0.993 in differentiating PCNSL from non-PCNSL lesions. Outperforming several pathologists, LGNet significantly improved diagnostic performance, further augmented to some extent by fusion approach. LGNet's proficiency in frozen section analysis and its synergy with pathologists indicate its valuable role in intraoperative diagnosis, particularly in discriminating PCNSL from glioma, alongside other lesions.

Evaluation of different body temperature measurement methods for patients in the intraoperative period.

OBJECTIVES: this study aimed at estimating and comparing the reliability of temperature measurements obtained using a peripheral infrared temporal thermometer, a central cutaneous thermometer ("Zero-Heat-Flux Cutaneous thermometer") and an esophageal or nasopharyngeal thermometer among elective surgical patients in the intraoperative period. METHOD: a longitudinal study with repeated measures carried out by convenience sampling of 99 patients, aged at least 18 years old, undergoing elective abdominal cancer surgeries, with anesthesia lasting at least one hour, with each patient having their temperature measured by all three methods. RESULTS: the intraclass correlation coefficient showed a low correlation between the measurements using the peripheral temporal thermometer and the central cutaneous (0.0324) and esophageal/nasopharyngeal (-0.138) thermometers. There was a high correlation (0.744) between the central thermometers evaluated. CONCLUSION: the data from the current study do not recommend using infrared temporal thermometers as a strategy for measuring the body temperature of patients undergoing anesthetic-surgical procedures. Central cutaneous thermometers and esophageal/nasopharyngeal thermometers are equivalent for detecting intraoperative hypothermia.

Comparison of Intraoperative Imprint Cytology versus Frozen Section for Sentinel Lymph Node Evaluation in Breast Cancer. A study along with Systematic Review and Meta-analysis of literature.

BACKGROUND: Sentinel lymph node (SLN) is the first lymph node to drain the lymph from a particular region involved by cancer. The commonly performed intraoperative methods for SLN evaluation are touch imprint cytology (TIC) and frozen section (FS). The present study aimed to determine the sensitivity, specificity and accuracy of TIC and FS with histopathological diagnosis as gold standard. MATERIALS AND METHODS: The nodes were bissected along their long axis and wet surface was imprinted on to clean glass slides followed by toluidine blue and rapid Papanicolaou staining. Subsequently the lymph node slices were cut at three levels using the cryostat machine and stained with Hematoxylin and eosin stain. The cytological and FS findings were compared and the specificity, sensitivity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of TIC and FS was evaluated taking histopathological diagnosis as gold standard. In addition, pooled sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for touch imprint cytology and frozen section were assessed for the studies included in the meta-analysis. RESULTS: The specificity, sensitivity, diagnostic accuracy, positive predictive value and negative predictive value of touch imprint cytology were 100%, 88.2%, 90%, 100% and 60% respectively. The specificity, sensitivity, diagnostic accuracy, PPV and NPV of frozen section were 100%, 94.1%, 95%, 100% and 75% respectively. The sensitivity of TIC and FS for detection of micrometastasis was 60% and 80% respectively. The pooled sensitivity and specificity for touch imprint cytology were 85.24% (95% CI, 83.46%-86.90%), and 98.99% (95% CI, 98.69%-99.23%) respectively. The pooled sensitivity and specificity for frozen section examination were 90.45% (95% CI, 85.15%-94.34%), and 100% (95% CI, 99.24%-100%) respectively. CONCLUSION: Even though the sensitivity of FS was better than imprint cytology in detection of micrometastasis, TIC is a rapid inexpensive technique which can be utilized in remote areas in absence of cryostat machine. The sensitivity of the two techniques with respect to detection of macrometastasis was comparable. This meta-analysis highlights the accuracy of the touch imprint cytology and frozen section examination in the intra-operative detection of malignancy in breast cancer.

Discrepancies Between Intraoperative and Postoperative Ankle Motion Measured for Anterior-Approach Total Ankle Arthroplasty.

BACKGROUND: Although intraoperative ankle motion serves as a foundational reference for anticipated motion after surgery and guides the addition of procedures to enhance ankle motion in total ankle arthroplasty (TAA), the relationship between intraoperative and postoperative ankle motion remains unclear. This study aimed to investigate the discrepancy between intraoperative and postoperative ankle range of motion (ROM) following TAAs using the anterior-approach, fixed-bearing systems. METHODS: This study retrospectively reviewed 67 patients (67 ankles) who underwent primary TAA at a single institution. Three different types of anterior-approach, fixed-bearing TAA systems were included. Intraoperative fluoroscopy was used to document the maximal dorsiflexion and plantar flexion at the end of the case. Standardized weightbearing maximum dorsiflexion and plantar flexion sagittal radiographs were obtained pre- and postoperatively, following a previously described method. The motion between 3 different time points (preoperative, intraoperative, and postoperative [mean 11.4 months]) was compared using pairwise t tests, and their differences were quantified. RESULTS: The mean total tibiotalar ROM was 38.1 degrees (SD 7.8) intraoperatively, and the postoperative total tibiotalar ROM was 24.2 degrees (SD 9.7) (P < .001), indicating that a mean of 65.3% (SD 26.7) of the intraoperative motion was maintained postoperatively. Intraoperative dorsiflexion (mean 11.6 [SD 4.5] degrees) showed no evidence of difference from postoperative dorsiflexion (mean 11.4 [SD 5.8] degrees, P > .99), indicating that a median of 95.6% (interquartile range: 66.2-112) of the intraoperative maximum dorsiflexion was maintained postoperatively. However, there was a significant difference between intraoperative plantarflexion (mean 26.4 [SD 6.3]) and postoperative plantarflexion (12.8 [SD 6.9] degrees, P < .001), indicating a mean 50.6% (SD 29.6) of intraoperative motion maintained in the postoperative assessment. There was an improvement of 2.5 degrees in the total tibiotalar ROM following TAA with statistical significance (P < .043). CONCLUSION: This study revealed a significant difference between intraoperative ankle ROM and ankle ROM approximately 1 year after anterior-approach, fixed-bearing TAA, mainly due to plantarflexion motion restriction. Minimal difference in dorsiflexion suggests the importance of achieving the desired postoperative dorsiflexion motion during the surgery using the best possible adjunct procedures. LEVEL OF EVIDENCE: Level IV, case series.

Intraoperative Regional Cerebral Oxygenation During Pediatric Thoracoscopic Surgery: A Systematic Review.

Background: Ventilating a pediatric patient during thoracoscopy is challenging. Few studies have highlighted the impact of capnothorax in children by measuring regional cerebral oxygen saturation (rcSO2) with near infrared spectroscopy. In this systematic review, we aimed to summarize the data from relevant studies and assess whether thoracoscopy in children is associated with intraoperative pathological cerebral desaturation. Methods: The authors systematically searched four databases for relevant studies on the measurement of rcSO2 during pediatric thoracoscopic procedures. The primary outcome was the proportion of patients with pathological desaturation, that is, >20% decline in the intraoperative rcSO2. Risk of bias among the included studies was estimated using the Newcastle-Ottawa scale. Results: The systematic search resulted in 776 articles, of which 7 studies were included in the analysis. In total, 88 patients (99 procedures) with an age ranging from 0 days to 8.1 years were included. Of these, 43 (49%) patients were neonates. The included cohort had esophageal atresia and tracheoesophageal fistula (n = 26), long-gap esophageal atresia (n = 5), congenital diaphragmatic hernia (n = 14), and congenital pulmonary airway malformations and other conditions needing lung resection (n = 43). Of the total 99 procedures, pathological desaturation was noticed in 13 (13.1%, 95% confidence interval 7.2-21.4) of them. Upon quality assessment, most of the studies were weaker in the selection and comparability domains. Conclusion: In this review, pathological cerebral desaturation was noticed in 13.1% of the pediatric thoracoscopic procedures. However, due to limited methodological quality of the included studies, further randomized multicentric studies comparing rcSO2 in open versus thoracoscopic surgeries are needed to derive definitive conclusions.

A prospective comparison of a modified miniaturised hand-held epifluorescence microscope and touch imprint cytology for evaluation of axillary sentinel lymph nodes intraoperatively in breast cancer patients.

BACKGROUND: The management of axillary lymph nodes in early-stage breast cancer patients has changed considerably, with the primary focus shifting from the examination of sentinel lymph nodes (SLNs) to toward the detection of all macro-metastases. However, current methods, such as touch imprint cytology (TIC) and frozen sections, are inadequate for clinical needs. To address this issue, we proposed a novel miniaturised epifluorescence widefield microscope (MEW-M) to assess SLN status intraoperatively for improved diagnostic efficiency. METHODS: A prospective, side-by-side comparison of intraoperative SLN evaluation between MEW-M and TIC was performed. RESULTS: A total of 73 patients with 319 SLNs consecutive enrolled in this study. MEW-M showed significantly superior image quality compared to TIC (median score 3.1 vs 2.1, p < 0.0001) and had a shorter time to issue results (10.3 vs 19.4 min, p < 0.0001). Likelihood ratio analysis illustrated that the positive likelihood ratio value of MEW-M compared with TIC was infinitely great vs 52.37 (95% CI, 21.96-124.90) in model 1 (classifying results into negative/positive), infinitely great vs 52.37 (95% CI, 21.96-124.90) in model 2 (classifying results into macro-metastasis/others, and TIC results followed the same classification as model 1), respectively. Similarly, the negative likelihood ratio values of MEW-M compared with TIC were 0.055 (95% CI, 0.018-0.160) and 0.074 (95% CI, 0.029-0.190) in model 1; and 0.019 (95% CI, 0.003-0.130) vs 0.020 (95% CI, 0.003-0.140) in model 2, respectively. CONCLUSIONS: MEW-M is a promising technique that can be utilised to provide a rapid and accurate intraoperative assessment of SLN in a clinical setting to help improve decision-making in axillary surgery.

Assessment of the need for routine intraoperative cell salvage in liver transplantation.

PURPOSE: This study aimed to assess the necessity of routine intraoperative cell salvage in liver transplantations. METHODS: A total of 327 liver transplants performed between 2014 and 2016 was included in the analysis. Patient data, including pre-transplant examinations, intraoperative red blood cell transfusions, and procedural information, were collected. RESULTS: The median age of the patients was 54 years old, with 67% (219) being male. The most prevalent ABO blood type was O, accounting for 48% (155) of cases. The leading causes of liver disease were hepatitis C (113 cases, 34.6%) and alcohol-related liver disease (97 cases, 29.7%). Out of the 327 liver transplants, allogeneic red blood cell transfusions were administered in 110 cases (34%) with a median of two units of red blood cells per case. Cell salvage was employed in 237 transplants (73%), and successful blood recovery was achieved in 221 cases (93%). Among the group that recovered more than 200 mL of blood, the median volume of recovered blood was 417 mL, with no transfusion of allogeneic blood required. A total of 90 transplants was performed without utilizing cell salvage, and, among these cases, 19 required blood transfusions, with a median of zero units transfused. CONCLUSIONS: This study suggests that routine cell salvage is unnecessary for all liver transplantations. The most suitable indication for its use is in patients presenting with portal vein thrombosis and abnormal creatinine levels.

First clinical application of image-guided intraoperative electron radiation therapy with real time intraoperative dose calculation in recurrent rectal cancer: technical procedure.

Intraoperative radiation therapy (IORT) is a radiation technique applying a single fraction with a high dose during surgery. We report the first abdomino-pelvic application of an image-guided intraoperative electron radiation therapy with intraoperative real time dose calculation based on the individual intraoperative patient anatomy. A patient suffering from locoregionally recurrent rectal cancer after treatment with neoadjuvant re-chemoradiation was chosen for this approach. After surgical removal of the recurrence, an adequate IORT applicator was placed as usual. A novel mobile imaging device (ImagingRing, MedPhoton) was positioned around the patient covering the region to be treated with the IORT-applicator in place. It allowed the acquisition of three-dimensional intraoperative cone-beam computed tomography images suitable for dose calculation using an automated scaling (heuristic object and head scatter as well as hardening corrections) of Hounsfield units. After image acquisition confirmed the correct applicator position, the images were transferred to our treatment planning system for intraoperative dose calculation. Treatment could be accomplished using the calculated dose distribution. We herein describe the details of the procedure including necessary adjustments in the typically used IORT equipment and work flow. We further discuss the pros and cons of this new approach generally overcoming a decade long limitation of IORT procedures as well as future perspectives regarding IORT treatments.

Role of intraoperative touch imprint cytology and immunohistochemistry in the diagnosis of metastatic malignancies in the central nervous system: Cyto-histomorphological findings and differential diagnosis.

BACKGROUND: Brain metastases (BMs) are intracranial neoplasms that are more common in adults than primary brain tumors, causing significant mortality and morbidity in cancer patients. This study aimed to evaluate the definitive histopathological diagnosis using touch imprint cytology and the importance and use of immunohistochemistry in the diagnosis of primary origin. METHOD: Cytological, paraffin section, and immunohistochemical study slides of all metastatic brain tumors consecutively consulted at the pathology department between 2018 and 2023 were evaluated. The sensitivity, specificity, and accuracy of patients' diagnostic results who underwent imprint cytology were compared based on the final diagnosis histopathological report. RESULTS: A total of 45 patients with and without intraoperative consultation were included in the study. The definitive histopathologic diagnosis and the diagnostic accuracy rate of imprint cytology for distinguishing glial and metastatic tumors on paraffin sections was 100%. Immunohistochemistry was performed in all patients (except one patient; immediate exitus) and histological classification of the primary tumor was performed by analysis of clinical findings and biomarkers. The primary origins of metastatic tumors were often lung and breast, with adenocarcinoma subtype histomorphology, cerebral hemispheres, and discrete foci of metastasis. CONCLUSION: TPs is a simple and rapid technique that supports diagnosis in intraoperative neuropathology and is a very cost-effective procedure. The pathologist's experience is the key factor in the diagnosis and reduces the need for a frozen section. In our series, the final histopathologic correlation of imprint cytology in the diagnosis of primary and metastatic tumors is 100%.

Intraoperative assessment of resection margins by Raman spectroscopy to guide oral cancer surgery.

Patients with oral cavity cancer are almost always treated with surgery. The goal is to remove the tumor with a margin of more than 5 mm of surrounding healthy tissue. Unfortunately, this is only achieved in about 15% to 26% of cases. Intraoperative assessment of tumor resection margins (IOARM) can dramatically improve surgical results. However, current methods are laborious, subjective, and logistically demanding. This hinders broad adoption of IOARM, to the detriment of patients. Here we present the development and validation of a high-wavenumber Raman spectroscopic technology, for quick and objective intraoperative measurement of resection margins on fresh specimens. It employs a thin fiber-optic needle probe, which is inserted into the tissue, to measure the distance between a resection surface and the tumor. A tissue classification model was developed to discriminate oral cavity squamous cell carcinoma (OCSCC) from healthy oral tissue, with a sensitivity of 0.85 and a specificity of 0.92. The tissue classification model was then used to develop a margin length prediction model, showing a mean difference between margin length predicted by Raman spectroscopy and histopathology of -0.17 mm.

Assessment of gastric pouch blood supply with indocyanine green fluorescence in conversional and revisional bariatric surgery: a prospective comparative study.

Our study aimed to evaluate the usefulness of indocyanine green (ICG) angiography during conversional or revisional bariatric surgery. We prospectively enrolled all patients scheduled for reoperative bariatric surgery with gastric pouch resizing and ICG assessment and we compared them with a retrospective series of similar patients who did not receive ICG. The primary outcome was the rate of intraoperative change in the surgical strategy due to the ICG test. We included 32 prospective patients receiving intraoperatively an ICG perfusion test and 48 propensity score-matched controls. The mean age was 50.7 ± 9.7 years, 67 (83.7%) patients were female, and the mean BMI was 36.8 ± 5.3 kg/m2. The patient characteristics were similar in both groups. The ICG angiography was successfully conducted in all patients, and no change of the surgical strategy was necessary. Postoperative complications were similar in both groups (6.2% vs. 8.3%, p = 0.846), as well as operative time (125 ± 43 vs. 133 ± 47 min, p = 0.454) and length of hospital stay (2.8 ± 1.0 vs. 3.3 ± 2.2 days, p = 0.213). Our study suggested that ICG fluorescence angiography might not have been useful for assessing the blood supply of the gastric pouch in patients who underwent reoperative bariatric surgery. Therefore, it remains uncertain whether the application of this technique is indicated.

Intraoperative Transpyloric Tube Insertion for Congenital Diaphragmatic Hernia: Analysis of Japanese Study Group Data.

BACKGROUND: Congenital diaphragmatic hernia (CDH) is a severe congenital disease. Some CDH infants suffer from gastro-esophageal reflux disease (GERD), even after surgical correction of gastric position. A transpyloric tube (TPT) is inserted into CDH patients under direct observation intraoperatively in some hospitals in Japan to establish early enteral feeding. This strategy avoids gastric expansion to maintain a better respiratory condition. However, it is unclear whether the strategy has a secure effect for patient prognosis. This study aimed to evaluate the effectiveness of intraoperative TPT insertion on enteral feeding and postoperative weight gain. METHODS: The Japanese CDH Study Group database was used to identify infants with CDH born between 2011 and 2016, who were then divided into two groups: the TPT group and gastric tube (GT) group. In the TPT group, infants underwent intraoperative TPT insertion; postoperative insertion/extraction of TPT was irrelevant to the analysis. Weight growth velocity (WGV) was calculated using the exponential model. Subgroup analysis was performed using Kitano's gastric position classification. RESULTS: We analyzed 204 infants, of which 99 and 105 were in the TPT and GT groups, respectively. Enteral nutrition (EN) in the TPT and GT groups was 52 ± 39 and 44 ± 41 kcal/kg/day (p = 0.17) at age 14 days (EN14), respectively, and 83 ± 40 and 78 ± 45 kcal/kg/day (p = 0.46) at age 21 days (EN21), respectively. WGV30 (WGV from day 0 to day 30) in the TPT and GT groups was 2.3 ± 3.0 and 2.8 ± 3.8 g/kg/day (p = 0.30), respectively, and WGV60 (WGV from day 0 to day 60) was 5.1 ± 2.3 and 6.0 ± 2.5 g/kg/day (p = 0.03), respectively. In infants with Kitano's Grade 2 + 3, EN14 in the TPT and GT groups was 38 ± 35 and 29 ± 35 kcal/kg/day (p = 0.24), respectively, EN21 was 73 ± 40 and 58 ± 45 kcal/kg/day (p = 0.13), respectively, WGV30 was 2.3 ± 3.2 and 2.0 ± 4.3 g/kg/day (p = 0.76), respectively, and WGV60 was 4.6 ± 2.3 and 5.2 ± 2.3 g/kg/day (p = 0.30), respectively. CONCLUSION: Intraoperative TPT insertion did not improve nutritional intake and WGV30. WGV60 in TPT was less than that in GT. In Grade 2 + 3 subgroup analysis, TPT also had no advantage. We could not recommend routine TPT insertion at surgery. LEVEL OF EVIDENCE: III.

A clinical Raman spectroscopy imaging system and safety requirements for in situ intraoperative tissue characterization.

Raman spectroscopy imaging is a technique that can be adapted for intraoperative tissue characterization to be used for surgical guidance. Here we present a macroscopic line scanning Raman imaging system that has been modified to ensure suitability for intraoperative use. The imaging system has a field of view of 1 × 1 cm2 and acquires Raman fingerprint images of 40 × 42 pixels, typically in less than 5 minutes. The system is mounted on a mobile cart, it is equiped with a passive support arm and possesses a removable and sterilizable probe muzzle. The results of a proof of concept study are presented in porcine adipose and muscle tissue. Supervised machine learning models (support vector machines and random forests) were trained and they were tested on a holdout dataset consisting of 7 Raman images (10 080 spectra) acquired in different animal tissues. This led to a detection accuracy >96% and prediction confidence maps providing a quantitative detection assessment for tissue border visualization. Further testing was accomplished on a dataset acquired with the imaging probe's contact muzzle and tailored classification models showed robust classifications capabilities with specificity, sensitivity and accuracy all surpassing 95% with a support vector machine classifier. Finally, laser safety, biosafety and sterilization of the system was assest. The safety assessment showed that the system's laser can be operated safetly according to the American National Standards Institute's standard for maximum permissible exposures for eyes and skin. It was further shown that during tissue interrogation, the temperature-history in cumulative equivalent minutes at 43 °C (CEM43 °C) never exceeded a safe threshold of 5 min.

Outcomes of perioperative vasopressor use for hemodynamic management of patients undergoing free flap surgery: A systematic review and meta-analysis.

This systematic review and meta-analysis investigates the objective evidence regarding outcomes in head and neck free flap surgeries using vasoactive agents in the perioperative period. A search was performed in PubMed, Cochrane, Web of Science, and Scopus databases. Inclusion criteria were clinical studies in which vasopressors were used in head and neck free flap surgery during the intraoperative and perioperative period. Eighteen studies (n = 5397) were included in the qualitative analysis and nine (n = 4381) in the meta-analysis. There was no difference in flap failure outcomes with perioperative vasopressor use in head and neck free flap surgery (n = 4015, OR = 0.93, 95% CI [0.60, 1.44]). When patients received vasopressors perioperatively, there was an associated decrease in flap-specific complications (n = 3881, OR = 0.69, 95% CI [0.55, 0.87]). Intraoperative vasopressor use does not negatively impact free tissue transfer outcomes in head and neck surgery and may reduce overall free flap complications.

Intraoperative cytology when cryostat is not available. A 7-year experience in a Peruvian cancer center.

BACKGROUND: Intraoperative cytology (IC) is an alternative to frozen-section (FS) diagnosis. We present our experience with and the diagnostic value of IC during a 7-year period when FS was not available in a Peruvian Cancer Center. MATERIAL AND METHODS: This 7-year retrospective single-arm review study includes IC procedures performed by three pathologists between 2012 and 2018. These IC reports were reviewed independently by one pathologist and were correlated with the histologic diagnoses, which were used as the gold standard. All IC preparations (imprint, scrape, and crush smears) were stained with hematoxylin and eosin. IC interpretations were categorized as: malignant, benign, atypical, and "deferred to permanent sections." Sensitivity, specificity, and positive and negative predictive values were calculated by use of standard methods. RESULTS: A total of 1814 IC cases prepared from various organs obtained from 887 patients were reviewed. Malignant, benign, atypical, and "deferred to permanent sections" IC diagnoses were 26.3%, 68.9%, 3.7%, and 1.9%, respectively. Atypical and deferred cases were excluded from the statistical analysis; thus 1712 cases were found to be eligible. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall diagnostic accuracy were 91.6%, 97.7%, 94.1%, 96.7%, and 96%, respectively. CONCLUSION: In experienced hands, IC is a rapid, cost-effective, and accurate alternative diagnostic modality for intraoperative diagnosis when FS is not available.