Artificial Intelligence in CT and MR Imaging for Oncological Applications.

Cancer care increasingly relies on imaging for patient management. The two most common cross-sectional imaging modalities in oncology are computed tomography (CT) and magnetic resonance imaging (MRI), which provide high-resolution anatomic and physiological imaging. Herewith is a summary of recent applications of rapidly advancing artificial intelligence (AI) in CT and MRI oncological imaging that addresses the benefits and challenges of the resultant opportunities with examples. Major challenges remain, such as how best to integrate AI developments into clinical radiology practice, the vigorous assessment of quantitative CT and MR imaging data accuracy, and reliability for clinical utility and research integrity in oncology. Such challenges necessitate an evaluation of the robustness of imaging biomarkers to be included in AI developments, a culture of data sharing, and the cooperation of knowledgeable academics with vendor scientists and companies operating in radiology and oncology fields. Herein, we will illustrate a few challenges and solutions of these efforts using novel methods for synthesizing different contrast modality images, auto-segmentation, and image reconstruction with examples from lung CT as well as abdome, pelvis, and head and neck MRI. The imaging community must embrace the need for quantitative CT and MRI metrics beyond lesion size measurement. AI methods for the extraction and longitudinal tracking of imaging metrics from registered lesions and understanding the tumor environment will be invaluable for interpreting disease status and treatment efficacy. This is an exciting time to work together to move the imaging field forward with narrow AI-specific tasks. New AI developments using CT and MRI datasets will be used to improve the personalized management of cancer patients.

Extraskeletal osteosarcoma of the orbit: A clinicopathologic case report and review of literature.

Primary extraskeletal osteosarcoma (EOS) is an extremely rare malignancy. In this report, the clinical course of a 32-year-old man presenting with proptoses is described. Medical history included Hirschsprung disease (HD), horseshoe kidney, azoospermia, and vertebral anomalies. Imaging of the orbit showed an oval, well-defined heterogeneous mass adjacent to the lateral wall of the orbit. The patient underwent a lateral orbitotomy and complete excision of the mass. The mass was not attached to the bone. Histopathologic and immunohistochemical examination confirmed the diagnosis of an EOS. The patient received chemotherapy and radiotherapy and is free of the disease 3 years after the diagnosis. Genetic screening showed no mutations for both the RET proto-oncogene for HD and the p53 tumor suppressor gene for osteosarcoma.

Nontraumatic orbital floor fracture after nose blowing.

A 40-year-old woman with no history of trauma or prior surgery presented to the emergency department with headache and left eye pain after nose blowing. Noncontrast maxillofacial computed tomography examination revealed an orbital floor fracture that ultimately required surgical repair. There are nontraumatic causes of orbital blowout fractures, and imaging should be obtained irrespective of trauma history.

Impact of image quality, radiologists, lung segments, and Gunnar eyewear on detectability of lung nodules in chest CT.

BACKGROUND: Despite the increasingly higher spatial and contrast resolution of CT, nodular lesions are prone to be missed on chest CT. Tinted lenses increase visual acuity and contrast sensitivity by filtering short wavelength light of solar and artificial origin. PURPOSE: To test the impact of Gunnar eyewear, image quality (standard versus low dose CT) and nodule location on detectability of lung nodules in CT and to compare their individual influence. MATERIAL AND METHODS: A pre-existing database of CT images of patients with lung nodules >5 mm, scanned with standard does image quality (150 ref mAs/120 kVp) and lower dose/quality (40 ref mAs/120 kVp), was used. Five radiologists read 60 chest CTs twice: once with Gunnar glasses and once without glasses with a 1 month break between. At both read-outs the cases were shown at lower dose or standard dose level to quantify the influence of both variables (eyewear vs. image quality) on nodule sensitivity. RESULTS: The sensitivity of CT for lung nodules increased significantly using Gunnar eyewear for two readers and insignificantly for two other readers. Over all, the mean sensitivity of all radiologist raised significantly from 50% to 53%, using the glasses (P value = 0.034). In contrast, sensitivity for lung nodules was not significantly affected by lowering the image quality from 150 to 40 ref mAs. The average sensitivity was 52% at low dose level, that was even 0.7% higher than at standard dose level (P value = 0.40). The strongest impact on sensitivity had the factors readers and nodule location (lung segments). CONCLUSION: Sensitivity for lung nodules was significantly enhanced by Gunnar eyewear (+3%), while lower image quality (40 ref mAs) had no impact on nodule sensitivity. Not using the glasses had a bigger impact on sensitivity than lowering the image quality.

Variability in the position of the retropharyngeal internal carotid artery.

The retropharyngeal internal carotid artery (ICA) is a well-described arterial anomaly with important implications for patients undergoing pharyngeal approach surgical procedures. Existing clinical and imaging classification schemes for a retropharyngeal ICA take into account arterial distance to the pharyngeal mucosal wall. We describe a case of mobility of a retropharyngeal ICA between short-interval imaging studies. The possibility of respiratory variability or other etiologies causing such changes in retropharyngeal carotid position have not been described previously. Our findings suggest that imaging findings from a single study alone may not be sufficient to confidently exclude this clinically significant arterial anomaly.

MRI perfusion in determining pseudoprogression in patients with glioblastoma.

We examine the role of dynamic susceptibility contrast (DSC) magnetic resonance imaging (MRI) perfusion in differentiating pseudoprogression from progression in 20 consecutive patients with treated glioblastoma. MRI perfusion was performed, and relative cerebral blood volume (rCBV), relative peak height (rPH), and percent signal recovery (PSR) were measured. Pseudoprogression demonstrated lower median rCBV (P=.009) and rPH (P<.001), and higher PSR (P=.039) than progression. DSC MRI perfusion successfully identified pseudoprogression in patients who did not require a change in treatment despite radiographic worsening following chemoradiotherapy.

Bilateral Marcus Gunn jaw winking synkinesis with monocular elevation deficiency: a case report and literature review.

Marcus Gunn jaw winking synkinesis (MGJWS) occurs due to an aberrant innervation of the levator palpebrae superioris muscle by a branch of the motor division of the trigeminal nerve that supplies the muscles of mastication. MGJWS is mostly unilateral occurring in isolation and is less frequently associated with ocular or systemic abnormalities. Although MGJWS is mostly unilateral, few bilateral cases have been reported. Here we describe a rare case of bilateral MGJWS in an 18 year-old male patient with asymmetric bilateral ptosis and monocular elevation deficiency in the right eye.

Insights into levator muscle dysfunction in a cohort of patients with molecularly confirmed blepharophimosis-ptosis-epicanthus inversus syndrome using high-resolution imaging, anatomic examination, and histopathologic examination.

OBJECTIVE: To study the basis of defective levator palpebrae superioris (LPS) function in blepharophimosis-ptosis-epicanthus inversus syndrome (BPES), an autosomal dominant eyelid malformation sometimes associated with ovarian dysfunction. METHODS: Eight patients with molecularly proved BPES underwent high-resolution surface-coil 3-T magnetic resonance imaging before surgical intervention. The features of LPS muscle and adjoining connective tissue were compared with an age-matched control subject. During LPS resection for ptosis repair, detailed anatomic examination of the LPS was performed. Histopathologic characteristics were compared with normal control samples from a cadaver and a patient with simple severe congenital ptosis. RESULTS: The most striking feature shown on magnetic resonance imaging was the thin, long anterior part of the LPS. During the operation, this consisted of a disorganized, thin, long aponeurosis. However, in the posterior part of the LPS, there was an organized thick structure suggestive of a muscle belly. Histopathologic examination revealed posteriorly well-formed striated muscle fibers in all patients with BPES but not in the control sample from the patient with simple severe congenital ptosis. These striated muscle fibers were comparable to those of the normal control tissue but were more intermixed with collagenous tissue and little fatty degeneration. CONCLUSIONS: The presence of striated muscle fibers in LPS of patients with BPES contrasts with the fatty degeneration in patients with simple severe congenital ptosis. To our knowledge, this is the first study providing novel insights into the pathogenesis of the eyelid malformation in BPES through extensive imaging, anatomic study, and histopathologic testing in a unique cohort of patients with molecularly proved BPES.

Occult orbito-cranial penetrating injury by pencil: role of beta tracer protein as a marker for cerebrospinal fluid leakage.

Orbito-cranial foreign bodies present a treacherous situation that can escape detection. The only evidence of these foreign bodies may be the entry wound in the form of a small lid laceration. A two-year-old boy presented with right upper lid laceration following a fall two hours back. Analysis of the fluid around the wound revealed a beta-tracer protein (beta-TP) value of 33.5 mg/l suggestive of cerebrospinal fluid (CSF). Three-dimensional computed tomography (CT) scan revealed a foreign body measuring 4.2 cm x 0.8 cm passing from the orbital roof to the frontal lobe. The foreign body tract was explored through the eyelid laceration and a broken pencil was removed followed by dural patch graft. The patient developed no ocular or intracranial complications. Beta-TP, a highly specific marker of CSF is routinely used in screening patients of neurosurgery and otolaryngology with CSF leaks, however, its use has never been reported in ophthalmic literature based on an online PubMed search.

Increased levator muscle function by supramaximal resection in patients with blepharophimosis-ptosis-epicanthus inversus syndrome.

OBJECTIVE: To study the efficacy and clinical and anatomical results of supramaximal levator resection in patients with blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) with severe congenital ptosis with poor levator function (LF). METHODS: Eleven patients with molecularly proven BPES underwent supramaximal levator resection. Palpebral fissure height and LF were measured preoperatively and postoperatively. RESULTS: All patients showed an excellent reduction in ptosis with a single intervention resulting in a clear visual axis. Palpebral fissure height improved from mean (SD) 3.3 (0.7) mm preoperatively to 7.1 (0.9) mm postoperatively (P value <.001). Four patients underwent additional surgery because of cosmetic issues with eyelid height asymmetry. All patients showed a marked, consistent, and lasting improvement in LF, going from mean (SD) 1.9 (0.9) mm preoperatively to 7.4 (1.1) mm postoperatively (P value <.001). This improvement could be attributed to the presence of a very long and thin tendon, as well as a striated muscle belly. This elongated aponeurosis inhibits the levator muscle from having sufficient impact on the vertical eyelid excursion. CONCLUSIONS: We demonstrated that supramaximal levator resection performed in patients with BPES not only results in good cosmetic appearance in terms of ptosis reduction in the majority of cases but also in a significant increase of the levator palpebrae superioris function. An anatomical substrate was found to explain these findings. To our knowledge, this is the first study to provide evidence of a marked increase in LF in BPES due to resection of the elongated tendon with reinsertion of the muscle belly.

Correction of the lower eyelid malpositioning in the blepharophimosis-ptosis-epicanthus inversus syndrome.

PURPOSE: Blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) is an autosomal dominant complex eyelid malformation. The authors aim to offer an explanation for the lower eyelid malformation and propose a novel surgical approach to correct it. METHODS: An observational and interventional case series of 10 consecutive, molecularly proven BPES patients who underwent surgical repair of the lower eyelid malformation. During surgery detailed anatomical examination and surgical repositioning of the medial canthal tendon was performed. All the patients were followed up regularly after the surgery and assessed for epiphora. RESULTS: All patients exhibited a marked asymmetry in the attachment of the lower and upper eyelid to the medial canthal tendon, with the lower eyelid being much less attached. This resulted in an abnormal downward concavity with a temporal ectropion and a temporally displaced lower eyelid. Consequently, the inferior punctum was displaced temporally. All patients underwent a novel surgical technique to remediate this, namely, inserting a 4.0 nylon suture between the tarsal plate of the lower eyelid and the medial canthal tendon during telecanthus surgery. This simple additional surgical step corrected not only the position of the lower eyelid but also its abnormal downward concavity, the temporal ectropion and the lateral displacement of the inferior punctum. None of the authors' patients had lasting epiphora. CONCLUSION: Lateral displacement of the inferior punctum is an important hallmark in the diagnosis of BPES. The authors demonstrate an anatomical explanation for the complex lower eyelid malformation and also propose a novel surgical technique to correct this. During surgical repair of the telecanthus and blepharophimosis, specific attention should be paid to reattachment of the lower eyelid to the medial canthal tendon. This understanding improves clinical diagnosis and surgical treatment of BPES patients.

Primary T cell/histiocyte-rich large B-cell lymphoma of the orbit.

T cell/histiocyte-rich large B-cell lymphoma (THRBCL) is an uncommon morphologic variant of diffuse large B-cell lymphoma characterized by a minor population of neoplastic B cells existing in a background of predominant reactive T lymphocytes. Diagnosis of this entity is occasionally difficult and would require careful immunohistochemical analysis of the tumor cells, as it may appear similar to other lymphoid diseases, such as nodular lymphocyte-predominant Hodgkin lymphoma, classical Hodgkin lymphoma, and peripheral T-cell lymphoma. The authors report a case of 37-year-old man who presented with a slowly growing, painless proptosis of the right eye with a well-defined mass in the posterosuperior aspect of globe. An incisional biopsy of the mass was performed. Histopathologic examination and immunohistochemical analysis revealed the diagnosis of THRBCL. To the best of the authors' knowledge, this is the first case of primary THRBCL occurring in the orbit.

Clinical features and management of posttraumatic subperiosteal hematoma of the orbit.

Traumatic subperiosteal hematoma (SpH) usually presents late, after the initial trauma. It is generally seen in young males. Computed tomography is the best mode of imaging and helps to rule out orbital fracture or associated subdural hematoma. We present the clinical features and management of four patients seen at the orbit clinic with SpH. Management is based on time of presentation, visual acuity and any communicating bleed. The prognosis of traumatic SpH is excellent if treated with an individualized patient approach.

Spectrum of orbital disease in South India: an aravind study of 6328 consecutive patients.

AIM: To review the incidence of orbital diseases in South India and to compare with other case series published. METHODS: Retrospective review of 6328 consecutive patients with orbital disease evaluated at Aravind Eye Hospital between January 1997 and December 2008. The main outcome measure was incidence of orbital disease in South Indian population, as determined by clinical and histopathologic criteria. A literature review was conducted to compare the results of this study with those of previously published reports. RESULTS: Of the 6328 patients, 2161 (34.1%) had inflammatory orbital disease, 1965 (31.0%) had systemic conditions involving the orbit, 1277 (20.1%) had neoplasm, 600 (9.4%) had congenital lesions, 308 (4.8%) had trauma, and 17 (0.2%) had vascular disease. Of the 2161 patients presenting with inflammatory disease, 1473 (68.1%) had idiopathic orbital inflammation, 270 (12.5%) had infection, 126 (5.8%) had dacryoadenitis, and 292 (13.5%) had other etiologies. Among the 1965 patients presenting with systemic disease involving the orbit, 1938 (98.6%) were diagnosed with thyroid orbitopathy, 22 (1.1%) with amyloidosis, and 5 (0.2%) with sarcoidosis. Of the 1277 patients with neoplasm, the tumor was vascular in 369 (28.8%), neural in 336 (26.3%), lymphoid or leukemic in 131 (10.2%), secondary neoplasm in 82 (6.4%), epithelial in 68 (5.3%), adipose in 53 (4.1%), metastatic in 39 (3.0%), and fibrous, fibro-osseous, striated muscle, histiocytic, and other cellular origin in 40 (3.1%), 37 (2.8%), 23 (1.8%), 21 (1.6%), and 78 (6.1%), respectively. Of the 600 patients with congenital lesions, 427 (71.1%) had dermoid and 170 (28.3%) had dermolipoma, followed by meningoencephalocele. CONCLUSIONS: The most common causes of orbital disease in South India are inflammatory (34.1%) and systemic conditions (31.0%). With the exception of higher incidence of inflammatory etiologies, these data are largely consistent with prior published reports.

Atypical presentation of an unusual foreign body.

A 14-year-old boy presented with intractable diplopia for 10 days following an assault. A thorough history revealed that he was unaware of any penetrating injury. However, imaging demonstrated a radiolucent foreign body between the globe and the orbital floor. On surgical exploration, it was found to be the proximal part of a ball point pen. Its removal resulted in complete resolution of diplopia. Thorough clinical and radiological examination is recommended when a foreign body is suspected in pediatric patients. Prompt diagnosis will aid in early intervention and prevention of long-term complications.

Isolated optic nerve infiltration in systemic lymphoma--a case report and review of literature.

Ocular involvement in non-Hodgkin lymphoma occurs either as primary ocular, central nervous system lymphoma or isolated intraocular lymphoma. Recurrence of systemic non-Hodgkin lymphoma in the form of CNS lymphoma has been reported. However, recurrence as an isolated optic nerve lesion without involving CNS has never been reported in the pediatric age group. We report a case of systemic diffuse large B-cell lymphoma in a 2-year-old female, which primarily occurred as suprapubic mass and later recurred in the form of isolated optic nerve infiltration, after remission of the primary disease. Early detection and prompt treatment resulted in complete reversal of the disease.

Primary adenoid cystic carcinoma of the eyelid.

Adenoid cystic carcinoma is a rare epithelial malignancy, which tends to grow slowly. It is an intractable neoplasm due to its ability to invade perineural spaces. A 59-year-old female presented with a gradually increasing mass in the right lower eyelid. An excisional biopsy with wide margins revealed a diagnosis of primary adenoid cystic carcinoma of eyelid skin with perineural invasion. Although a rare neoplasm, primary adenoid cystic carcinoma of eyelid skin should be included in the differential diagnosis of eyelid tumors.

Orbital hyalinizing spindle cell tumor with giant rosettes.

PURPOSE: To evaluate the clinical and histopathologic characteristics of orbital hyalinizing spindle cell tumor with giant rosettes (HSCTGR). METHODS: Interventional case series of 2 patients, aged 4 and 9 years referred to the Ocular Oncology Unit. Both patients presented with slowly progressive proptosis with dimness of vision in the second patient. CT was performed for both patients followed by excision of the masses. Histology was performed on tissue sections. RESULTS: CT revealed a localized tumor in the first case and extensive mass extending to the optic canal in the second patient. Histologic analysis revealed features of HSCTGR with characteristic spindle-shaped cells with giant rosettes with hyalinized foci. Tumor cells were positive for vimentin in both cases and focal S100 positivity in first case. However, the second case showed a higher Ki-67 index compared to the first case, suggestive of moderately high proliferative activity. After excision, neither of the tumors demonstrated local recurrence, and both patients were without regional or distant metastases. Mean clinical follow-up was 12 months. CONCLUSIONS: HSCTGR involving the orbit has not been previously reported in the literature. We report 2 cases of orbital presentation at a much younger age than has been shown in patients with this type of tumor in other areas of the body. Complete excision of this tumor with close follow-up is the preferred treatment. HSCTGR should be considered in the differential diagnosis of orbital fibrous tumor presenting as painless progressive proptosis.

Neglected giant atypical fibroxanthoma of the eyelid.

Atypical fibroxanthoma is an uncommon neoplasm of the superficial soft tissue that occurs in actinically damaged skin of elderly patients. It is characterized by a pleomorphic histologic appearance but has a generally favorable clinical course. These lesions are usually small in size and rarely occur on the eyelid. The authors present an unusual case of neglected giant atypical fibroxanthoma of the eyelid in an elderly patient.