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Purpose: A prospective, randomised, masked study comparing three different intraocular infusion solutions used during vitrectomy on postoperative electroretinography (ERG) and retinal histology of rabbit eyes., Methods Materials and Animals: Twelve rabbit eyes were used with each group of three intraocular infusion solutions: Lactated Ringers (LR), balanced salt solution (BSS) and balanced salt solution-plus (BSS-Plus)., Results: At 24 hours postoperatively, the ERG values were 36%, 68% and 75% of the normal values for LR, BSS and BSS-Plus, respectively. At 72 hours postoperatively, the ERG values were 50%, 84% and 100% of the normal values for LR, BSS and BSS-Plus, respectively. At 72 hours postoperatively, 3/12, 10/12 and 12/12 of the vitrectomised eyes had regained normal-value ERGs for LR, BSS, and BSS-Plus eyes, respectively. At 1 week postoperatively, 4/12 and 12/12 of LR and BSS eyes, respectively, had normal ERGs. The number of LR eyes regaining normal ERG values was 4/12, 6/12 and 9/12, measured at 1, 4 and 15 weeks postoperatively, respectively., Retina Histology: At 15 weeks follow-up, histopathology was performed on several rabbit eyes. Histological examination of LR-irrigated eyes showed 2/7 normal retinas, whereas 5/7 showed changes that ranged from vacuoles in the inner retina to numerous vacuoles in both the outer and inner retina with disruption of the inner nuclear layer. The histology of BSS-infused and BSS-Plus-infused rabbit eyes was normal., Conclusion: LR solution, when used during vitrectomy, has a more prolonged negative effect on ERG than BSS and BSS-Plus. Histological changes seen in LR eyes may explain the ERG results., Competing Interests: Competing interests: None declared.

Distant extrapelvic metastases appear in approximately in 10% of the patients with squamous cell anal cancer (SCAC) and survival depends on the treatment strategy. Exact staging leads to optimal planning of multimodality therapy and the adequate evaluation of treatment response can improve the prognosis of the disease. Diagnosis and staging of SCAC are commonly performed using contrast-enhanced computerized tomography(CT) and interpretation of the findings for tumor biological behavior. F18-fluoro-2 deoxy-D glucose positron emission tomography((18)F-FDG PET) reveals aspects of tumor function and allows metabolic measurements. Combined PET/CT scans permit exact localization with anatomical criteria of the hypermetabolic (18)F-FDG avid malignant lesions. We present a patient with SCAC in whom, according to PET/CT findings, the initial stage was changed from II (T2N0M0) to III A (T2N2M0). Radiation therapy (RT) and chemotherapy achieved a good therapeutic response but early follow up revealed new paraaortic lymph node (LN) metastases, as well as an uncommon left supraclavicular LN metastasis from the same primary carcinoma. The disease was restaged as stage IV (T2N2M1) and radiation therapy was substituted by chemotherapy.

Background: The purpose of this manuscript is to present the findings in the largest series of SPECT brain perfusion imaging reported to date for mild or moderate traumatic brain injury., Patients and Methods: This is a retrospective evaluation of 228 SPECT brain perfusion-imaging studies of patients who suffered mild or moderate traumatic brain injury with or without loss of consciousness (LOC). All patients had no past medical history of previous brain trauma, neurological, or psychiatric diseases, HIV, alcohol or drug abuse. The patient population included 135 males and 93 females. The ages ranged from 11-88 years (mean 40.8). The most common complaints were characteristic of the postconcussion syndrome: headaches 139/228 (61%); dizziness 61/228 (27%); and memory problems 63/228 (28%). LOC status was reported to be positive in 121/228 (53%), negative in 41/228 (18%), and unknown for 63/228 (28%)., Results: Normal studies accounted for 52/228 (23%). For abnormal studies (176/228 or 77%) the findings were as follows: basal ganglia hypoperfusion 338 lesions (55.2%); frontal lobe hypoperfusion 146 (23.8%); temporal lobes hypoperfusion 80 (13%); parietal lobes hypoperfusion 20 (3.7%); insular and or occipital lobes hypoperfusion 28 (4.6%). Patients' symptoms correlated with the SPECT brain perfusion findings. The SPECT BPI studies in 122/228 (54%) were done early within 3 months of the date of the accident, and for the remainder, 106/228 (46%) over 3 months and less than 3 years from the date of the injury. In early imaging, 382 lesions were detected; in 92 patients (average 4.2 lesions per study) imaging after 3 months detected 230 lesions: in 84 patients (average 2.7 lesions per study)., Conclusions: Basal ganglia hypoperfusion is the most common abnormality following mild or moderate traumatic brain injury (p = 0.006), and is more common in patients complaining of memory problem (p = 0.0005) and dizziness (p = 0.003). Early imaging can detect more lesions than delayed imaging (p = 0.0011). SPECT brain perfusion abnormalities can occur in the absence of LOC.

Unlabelled: Accurate assessment of lung carcinoma remains a significant clinical problem, often leading to surgical procedures without curative potential. PET with 18F-fluorodeoxyglucose (FDG) has shown promise in differentiating benign from malignant lesions and in staging the extent of disease, resulting in improved treatment at a significant cost savings. This multicenter prospective study used dual-detector coincidence imaging with FDG to categorize pulmonary lesions as benign or malignant. The goal of this study was to determine the sensitivity and specificity of dual-detector coincidence imaging of FDG in patients with pulmonary lesions who were scheduled to have a diagnostic procedure for histopathologic confirmation., Methods: A total of 96 patients with pulmonary lesions with a lesion size ranging from 1 to 7 cm with a mean of 3.44 cm based on their chest radiograph or CT scan were studied using FDG scans with a dual-detector coincidence detection system. An additional 24 patients were entered as control subjects. The studies of 120 subjects were interpreted in random order by three physicians experienced in the use of FDG in patients with lung cancer. Surgical pathology was used as the standard for identifying malignant lesions., Results: There was 94% agreement between the readers in the independent interpretation of the FDG studies. In the 96 patients with pulmonary lesions, FDG studies were 97% sensitive and 80% specific in identifying proven malignant lesions., Conclusion: The results of this prospective study provide evidence that dual-detector coincidence imaging with FDG provides an accurate, sensitive and specific means of diagnosing malignancy in patients with pulmonary lesions.

We report our experience with coincidence detection imaging of 18F-fluorodeoxyglucose (FDG) using a dual-head gamma camera. Scanning of the pelvis and abdomen of a patient with recurrent colorectal carcinoma showed recurrent disease in the pelvic floor and the base of the urinary bladder and metastatic disease in the retroperitoneal space of the pelvis. Although the tumor involving the bladder and pelvic floor was detected by CT and magnetic resonance imaging (MRI), metastatic spread to the retroperitoneal nodes on the left side was detected only by 18F-FDG imaging. Based on the ultrasound, CT, MRI and cystoscopy, a local recurrence of cancer was presumed in our patient. An exploratory laparotomy was performed to resect the tumor in its entirety. At the time of surgery, the retroperitoneal metastasis in the pelvis was confirmed. Had the findings of the coincidence detection imaging study been considered, the patient would have been spared the surgical procedure.

Intraperitoneal installation of chemotherapy through a Mediport implanted subcutaneously in the abdominal wall is used currently for treatment of peritoneal metastases from ovarian, gastric and colonic carcinoma. There is a variable incidence of complications due to the procedure reported in the literature. The main predisposing factor for these complications is the inhomogeneous distribution of the chemotherapeutic drugs within the peritoneal cavity. We report an unusual case of a rectosigmoid fistula that developed 6 wk following the insertion of a Bardport subcutaneously in the abdominal wall for intraperitoneal therapy. The fistula was clearly demonstrated by dynamic scintigraphic peritoneography. This is a new modification of scintigraphic peritoneography as practiced routinely. We endorse the previous recommendation that scintigraphic peritoneography be performed before every intraperitoneal installation of a chemotherapeutic drug or radiopharmaceutical to ensure the homogeneous distribution of the drugs and to prevent complications.

We report an unusual finding in an AIDS patient who presented with a large mediastinal mass and multiple lymphadenopathy. A sequential thallium and gallium scan to specify the nature of the mediastinal mass was requested. The early thallium images, acquired 15 min after the intravenous injection, showed no uptake in the mass. The delayed images 2 hr later showed intense thallium uptake. A gallium scan performed 48 hr later also showed intense gallium uptake in the mediastinal mass. Biopsy from the inguinal lymph node confirmed the presence of large-cell diffuse noncleaved malignant lymphoma. This case raises questions about the optimum time of imaging for thallium in high-grade lymphoma, whether delayed imaging is essential, about previous reports of low sensitivity of thallium in undifferentiated lymphoma and about the mechanism of thallium uptake in this type of tumor.

A 79-yr-old woman with asymptomatic subclavian vein thrombosis associated with transvenous pacemaker electrode and congestive heart failure is reported. The subclavian thrombosis was discovered accidentally from the first-pass radionuclide angiogram that is routinely performed with the intravenous bolus injection of the radiopharmaceutical for a gated blood-pool study. It demonstrated venous obstruction at the level of the subclavian vein and abnormal collateral circulation over the chest wall consistent with subclavian thrombosis. This case report and literature review demonstrates the importance of performing first-pass radionuclide cardioangiography routinely before multigated blood-pool studies in patients with pacemakers.

Unlabelled: With decreasing incidence of pneumocystis carinii pneumonia (PCP) in AIDS as a result of prophylactic regimens, there is a higher incidence of tuberculosis (TB), mycobacterium avii complex (MAC), kaposi sarcoma and malignant lymphoma. There is a need for differentiating these various pathological entities. The purpose of this study was for a retrospective evaluation of sequential thallium and gallium scans in AIDS patients for differentiating intrathoracic kaposi sarcoma from malignant lymphoma and opportunistic infections., Methods: A total of 181 patients had both studies completed between March 1992 and May 1994. The final diagnosis was verified only in 83 patients. Results were correlated with the CD4 counts, bronchoscopic and chest radiograph findings., Results: In patients with pulmonary kaposi sarcoma and no opportunistic infections (19 patients), a thallium-positive, gallium-negative pattern was detected in 17 patients with a sensitivity of 89%. In the presence of kaposi sarcoma plus opportunistic infections, this pattern was only detected in 7 of 19 patients (sensitivity dropped to 37%). In 45 patients with opportunistic infections and no kaposi sarcoma, only two false-positive findings were found in patients with cytomegalic virus pneumonia for a specificity of 96%. For the whole group of 83 patients, sensitivity was 63%; specificity 95%; positive predictive value 92%; accuracy 81%; and negative predictive value 75%., Conclusion: A thallium-positive, gallium-negative pattern in AIDS patients has a high specificity for the diagnosis of kaposi sarcoma, however, the sensitivity dropped from 89% to 37% in the presence of opportunistic infections.

Unlabelled: For many years, 32P-chromic phosphate (32P-CP) intraperitoneal instillations and platinum analogue chemotherapy have been used to treat disseminated ovarian cancer. To investigate possible enhancement of 32P-CP irradiation due to the concomitant administration of chemotherapy, in vitro studies were undertaken. Based on those laboratory investigations, a clinical regimen of combined 32P-CP and platinum analogue chemotherapy was developed., Methods: In vitro enhancement of 32P-CP cytotoxicity by cisplatin was studied in cultured human ovarian adenocarcinoma (CHOA) cell lines and in a fibroblast cell strain. In addition, ovarian cancer cells obtained from the malignant abdominal ascites and pleural effusions of 10 individual patients were also studied ex vivo. As part of routine clinical care, 30 patients with disseminated ovarian adenocarcinoma underwent up to eight monthly cycles of platinum analogue chemotherapy with concomitant intraperitoneal instillation of 5 mCi of 32P-CP at each monthly chemotherapy cycle., Results: There was an enhanced and possibly supra-additive effect of cisplatin on the cytotoxicity from 32P-CP irradiation. For the 30 patients, the survival rate at 3 yr was 63%., Conclusion: Phosphorus-32 CP low-dose intraperitoneal treatments in conjunction with platinum analogue chemotherapy is a promising approach for the treatment of disseminated intraperitoneal ovarian cancer.

Diffuse abnormal uptake of 201Tl-chloride in the bone marrow is described in an AIDS patient with Kaposi's sarcoma who received chemotherapy. The patient developed severe leukopenia that was treated by granulocyte stimulating factor (GCSF). The white blood cells increased from 1500 to 6200 over a period of 4 days. After chemotherapy, the tumor was negative for thallium uptake.

A case of primary thyroid lymphoma demonstrating uptake of 99mTc-hexakis-2-methoxy isobutyl isonitrile (MIBI) is presented. The 99mTc-MIBI image more clearly delineated the extent of tumor as demonstrated on CT compared to 201Tl-chloride and [99mTc]pertechnetate images. Following two courses of chemotherapy, repeat radionuclide studies and CT scan showed complete resolution of the thyroid tumor. Technetium-99m-MIBI may be useful in the assessment of disease activity and monitoring response to treatment in patients with lymphoma.

Imaging of the spleen of 10 patients who had been hematologically diagnosed with sickle-cell anemia (SCA) was studied with [99mTc]tin colloid and heat denatured [99mTc]RBCs. In all ten patients, there was faint or nonvisualization of the spleen with [99mTc]tin colloid. However, with heat denatured [99mTc]RBCs, nine spleens were well visualized, and the uptake was homogenous. One spleen had two patchy areas of uptake. The results indicate that when splenic phagocytic function is impaired as reflected by nonvisualization of the spleen with [99mTc]tin colloid, it is still possible to image such a spleen with heat denatured [99mTc]RBCs.